Commit Graph

8420 Commits

Author SHA1 Message Date
Josh Triplett
b8d57a76d9 rcutorture: Occasionally delay readers enough to make RCU force_quiescent_state
rcutorture already delays readers, but never for long enough to
make RCU force a quiescent state.  Add an occasional delay of
50ms.

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
LKML-Reference: <12524504772607-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-18 00:05:34 +02:00
Paul E. McKenney
b835db1f9c rcu: Initialize multi-level RCU grace periods holding locks
Prior implementations initialized the root and any internal
nodes without holding locks, then initialized the leaves
holding locks.

This is a false economy, as the leaf nodes will usually greatly
outnumber the root and internal nodes.  Acquiring locks on all
nodes is conceptually much simpler as well.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
LKML-Reference: <12524504773190-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-18 00:05:14 +02:00
Paul E. McKenney
de078d875c rcu: Need to update rnp->gpnum if preemptable RCU is to be reliable
Without this patch, tasks preempted in RCU read-side critical
sections can fail to block the grace period, given that
rnp->gpnum is used to determine which rnp->blocked_tasks[]
element the preempted task is enqueued on.

Before the patch, rnp->gpnum is always zero, so preempted tasks
are always enqueued on rnp->blocked_tasks[0], which is correct
only when the current CPU has not checked into the current
grace period and the grace-period number is even, or,
similarly, if the current CPU -has- checked into the current
grace period and the grace-period number is odd.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
LKML-Reference: <12524504771622-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-18 00:04:54 +02:00
Peter Zijlstra
2667de81f3 perf_counter: Allow for a wakeup watermark
Currently we wake the mmap() consumer once every PAGE_SIZE of data
and/or once event wakeup_events when specified.

For high speed sampling this results in too many wakeups wrt. the
buffer size, hence change this.

We move the default wakeup limit to 1/4-th the buffer size, and
provide for means to manually specify this limit.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-17 22:08:26 +02:00
Peter Zijlstra
850bc73ffc perf_counter: Do not throttle single swcounter events
We can have swcounter events that contribute more than a single
count per event, when used with a non-zero period, those can
generate multiple events, which is when we need throttling.

However, swcounter that contribute only a single count per event
can only come as fast as we can run code, hence don't throttle
them.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-17 22:08:25 +02:00
Li Zefan
5dd4de587f softirq: add BLOCK_IOPOLL to softirq_to_name
With BLOCK_IOPOLL_SOFTIRQ added, softirq_to_name[] and
show_softirq_name() needs to be updated.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4AB20398.8070209@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-17 15:53:44 -04:00
Steven Rostedt
b375a11a23 tracing: switch function prints from %pf to %ps
For direct function pointers (like what mcount provides) PowerPC64
requires the use of %ps, otherwise nothing is printed.

This patch converts all prints of functions retrieved through mcount
to use the %ps format from the %pf.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-17 15:53:40 -04:00
Ingo Molnar
45bd00d31d Merge branch 'linus' into tracing/core
Merge reason: Pick up kernel/softirq.c update for dependent fix.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-17 20:53:10 +02:00
Peter Zijlstra
29cd8bae39 sched: Fix SD_POWERSAVING_BALANCE|SD_PREFER_LOCAL vs SD_WAKE_AFFINE
The SD_POWERSAVING_BALANCE|SD_PREFER_LOCAL code can break out of
the domain iteration early, making us miss the SD_WAKE_AFFINE bits.

Fix this by continuing iteration until there is no need for a
larger domain.

This also cleans up the cgroup stuff a bit, but not having two
update_shares() invocations.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-17 10:40:31 +02:00
Peter Zijlstra
de69a80be3 sched: Stop buddies from hogging the system
Clear buddies more agressively.

The (theoretical, haven't actually observed any of this) problem is
that when we do not select either buddy in pick_next_entity()
because they are too far ahead of the left-most task, we do not
clear the buddies.

This means that as soon as we service the left-most task, these
same buddies will be tried again on the next schedule. Now if the
left-most task was a pure hog, it wouldn't have done any wakeups
and it wouldn't have set buddies of its own. That leads to the old
buddies dominating, which would lead to bad latencies.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-17 10:40:30 +02:00
Peter Zijlstra
ad4b78bbcb sched: Add new wakeup preemption mode: WAKEUP_RUNNING
Create a new wakeup preemption mode, preempt towards tasks that run
shorter on avg. It sets next buddy to be sure we actually run the task
we preempted for.

Test results:

 root@twins:~# while :; do :; done &
 [1] 6537
 root@twins:~# while :; do :; done &
 [2] 6538
 root@twins:~# while :; do :; done &
 [3] 6539
 root@twins:~# while :; do :; done &
 [4] 6540

 root@twins:/home/peter# ./latt -c4 sleep 4
 Entries: 48 (clients=4)

 Averages:
 ------------------------------
        Max          4750 usec
        Avg           497 usec
        Stdev         737 usec

 root@twins:/home/peter# echo WAKEUP_RUNNING > /debug/sched_features

 root@twins:/home/peter# ./latt -c4 sleep 4
 Entries: 48 (clients=4)

 Averages:
 ------------------------------
        Max            14 usec
        Avg             5 usec
        Stdev           3 usec

Disabled by default - needs more testing.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <new-submission>
2009-09-17 10:17:25 +02:00
Ingo Molnar
eb24073bc1 sched: Fix TASK_WAKING & loadaverage breakage
Fix this:

top - 21:54:00 up  2:59,  1 user,  load average: 432512.33, 426421.74, 417432.74

Which happens because we now set TASK_WAKING before activate_task().

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-17 09:51:20 +02:00
Ananth N Mavinakayanahalli
1f0ab40976 kprobes: Prevent re-registration of the same kprobe
Prevent re-registration of the same kprobe. This situation, though
unlikely, needs to be flagged since it can lead to a system crash if
it's not handled.

The core change itself is small, but the helper routine needed to be
moved around a bit; hence the diffstat.

Signed-off-by: Ananth N Mavinakayanahalli<ananth@in.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <20090915051307.GB26458@in.ibm.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-09-17 04:24:57 +02:00
Masami Hiramatsu
5a0d9050db tracing/kprobes: Disable kprobe events by default after creation
Disable newly created kprobe events by default, not to disturb
another user using ftrace. "Disturb" means when someone is using
ftrace and another user tries to use perf-tools, (in near
future) if he defines new kprobe event via perf-tools, then new
events will mess up the frace buffer. Fix this to allow proper
and transparent kprobes events concurrent usage between ftrace
users and perf users.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <20090914204937.18779.59422.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-09-17 04:04:01 +02:00
Masami Hiramatsu
74ebb63e7c tracing/kprobes: Fix profiling alignment for perf_counter buffer
Fix *probe_profile_func() to align buffer size, since perf_counter
requires its buffer entries to be 8 bytes aligned.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <20090914204928.18779.60029.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-09-17 04:03:57 +02:00
Masami Hiramatsu
50d7805607 tracing/kprobes: Add probe handler dispatcher to support perf and ftrace concurrent use
Add kprobe_dispatcher and kretprobe_dispatcher to dispatch event
in both profile and tracing handlers.

This allows simultaneous kprobe uses by ftrace and perf.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <20090914204920.18779.57555.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-09-17 04:03:54 +02:00
Masami Hiramatsu
4fead8e46f ftrace: Fix trace_remove_event_call() to lock trace_event_mutex
Lock not only event_mutex but also trace_event_mutex in
trace_remove_event_call() to protect __unregister_ftrace_event().

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <20090914204912.18779.68734.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-09-17 04:03:50 +02:00
Masami Hiramatsu
588bebb74f ftrace: Fix trace_add_event_call() to initialize list
Handle failure path in trace_add_event_call() to fix the below bug
which occurred when I tried to add invalid event twice.

Could not create debugfs 'kmalloc' directory
Failed to register kprobe event: kmalloc
Faild to register probe event(-1)
------------[ cut here ]------------
WARNING: at /home/mhiramat/ksrc/random-tracing/lib/list_debug.c:26
__list_add+0x27/0x5c()
Hardware name:
list_add corruption. next->prev should be prev (c07d78cc), but was
00001000. (next=d854236c).
Modules linked in: sunrpc uinput virtio_net virtio_balloon i2c_piix4 pcspkr
i2c_core virtio_blk virtio_pci virtio_ring virtio [last unloaded:
scsi_wait_scan]
Pid: 1394, comm: tee Not tainted 2.6.31-rc9 #51
Call Trace:
 [<c0438424>] warn_slowpath_common+0x65/0x7c
 [<c05371b3>] ? __list_add+0x27/0x5c
 [<c043846f>] warn_slowpath_fmt+0x24/0x27
 [<c05371b3>] __list_add+0x27/0x5c
 [<c047f050>] list_add+0xa/0xc
 [<c047f8f5>] trace_add_event_call+0x60/0x97
 [<c0483133>] command_trace_probe+0x42c/0x51b
 [<c044a1b3>] ? remove_wait_queue+0x22/0x27
 [<c042a9c0>] ? __wake_up+0x32/0x3b
 [<c04832f6>] probes_write+0xd4/0x10a
 [<c0483222>] ? probes_write+0x0/0x10a
 [<c04b27a9>] vfs_write+0x80/0xdf
 [<c04b289c>] sys_write+0x3b/0x5d
 [<c0670d41>] syscall_call+0x7/0xb
---[ end trace 2b962b5dc1fdc07d ]---

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <4AB1077F.6020107@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-09-17 04:03:46 +02:00
Masami Hiramatsu
2d5e067edc tracing/kprobes: Fix trace_probe registration order
Fix trace_probe registration order. ftrace_event_call and ftrace_event
must be registered before kprobe/kretprobe, because tracing/profiling
handlers dereference the event-id.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <20090914204856.18779.52961.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-09-17 04:03:40 +02:00
Masami Hiramatsu
f52487e9c0 tracing/kprobes: Support custom subsystem for each kprobe event
Support specifying a custom subsystem(group) for each kprobe event.
This allows users to create new group to control several probes
at once, or add events to existing groups as additional tracepoints.

New synopsis:
 p[:[subsys/]event-name] KADDR|KSYM[+offs] [ARGS]

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <20090910235353.22412.15149.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-09-17 04:03:24 +02:00
Linus Torvalds
ab86e5765d Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6:
  Driver Core: devtmpfs - kernel-maintained tmpfs-based /dev
  debugfs: Modify default debugfs directory for debugging pktcdvd.
  debugfs: Modified default dir of debugfs for debugging UHCI.
  debugfs: Change debugfs directory of IWMC3200
  debugfs: Change debuhgfs directory of trace-events-sample.h
  debugfs: Fix mount directory of debugfs by default in events.txt
  hpilo: add poll f_op
  hpilo: add interrupt handler
  hpilo: staging for interrupt handling
  driver core: platform_device_add_data(): use kmemdup()
  Driver core: Add support for compatibility classes
  uio: add generic driver for PCI 2.3 devices
  driver-core: move dma-coherent.c from kernel to driver/base
  mem_class: fix bug
  mem_class: use minor as index instead of searching the array
  driver model: constify attribute groups
  UIO: remove 'default n' from Kconfig
  Driver core: Add accessor for device platform data
  Driver core: move dev_get/set_drvdata to drivers/base/dd.c
  Driver core: add new device to bus's list before probing
2009-09-16 08:27:10 -07:00
Linus Torvalds
6b7b352f21 Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  block: fix linkage problem with blk_iopoll and !CONFIG_BLOCK
2009-09-16 07:46:34 -07:00
Peter Zijlstra
5a9b86f647 sched: Rename flags to wake_flags
For consistencies sake, rename the argument (again).

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-16 16:44:33 +02:00
Peter Zijlstra
5158f4e442 sched: Clean up the load_idx selection in select_task_rq_fair
Clean up the code a little.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-16 16:44:32 +02:00
Peter Zijlstra
3b64089422 sched: Optimize cgroup vs wakeup a bit
We don't need to call update_shares() for each domain we iterate,
just got the largets one.

However, we should call it before wake_affine() as well, so that
that can use up-to-date values too.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-16 16:44:32 +02:00
Atsushi Tsuji
b36461da2a tracing: Fix minor bugs for __unregister_ftrace_function_probe
Fix the condition of strcmp for "*".
Also fix NULL pointer dereference when glob is NULL.

Signed-off-by: Atsushi Tsuji <a-tsuji@bk.jp.nec.com>
LKML-Reference: <4AAF6726.5090905@bk.jp.nec.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-16 09:08:54 -04:00
Andi Kleen
6a46079cf5 HWPOISON: The high level memory error handler in the VM v7
Add the high level memory handler that poisons pages
that got corrupted by hardware (typically by a two bit flip in a DIMM
or a cache) on the Linux level. The goal is to prevent everyone
from accessing these pages in the future.

This done at the VM level by marking a page hwpoisoned
and doing the appropriate action based on the type of page
it is.

The code that does this is portable and lives in mm/memory-failure.c

To quote the overview comment:

High level machine check handler. Handles pages reported by the
hardware as being corrupted usually due to a 2bit ECC memory or cache
failure.

This focuses on pages detected as corrupted in the background.
When the current CPU tries to consume corruption the currently
running process can just be killed directly instead. This implies
that if the error cannot be handled for some reason it's safe to
just ignore it because no corruption has been consumed yet. Instead
when that happens another machine check will happen.

Handles page cache pages in various states. The tricky part
here is that we can access any page asynchronous to other VM
users, because memory failures could happen anytime and anywhere,
possibly violating some of their assumptions. This is why this code
has to be extremely careful. Generally it tries to use normal locking
rules, as in get the standard locks, even if that means the
error handling takes potentially a long time.

Some of the operations here are somewhat inefficient and have non
linear algorithmic complexity, because the data structures have not
been optimized for this case. This is in particular the case
for the mapping from a vma to a process. Since this case is expected
to be rare we hope we can get away with this.

There are in principle two strategies to kill processes on poison:
- just unmap the data and wait for an actual reference before
killing
- kill as soon as corruption is detected.
Both have advantages and disadvantages and should be used
in different situations. Right now both are implemented and can
be switched with a new sysctl vm.memory_failure_early_kill
The default is early kill.

The patch does some rmap data structure walking on its own to collect
processes to kill. This is unusual because normally all rmap data structure
knowledge is in rmap.c only. I put it here for now to keep
everything together and rmap knowledge has been seeping out anyways

Includes contributions from Johannes Weiner, Chris Mason, Fengguang Wu,
Nick Piggin (who did a lot of great work) and others.

Cc: npiggin@suse.de
Cc: riel@redhat.com
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
2009-09-16 11:50:15 +02:00
Andi Kleen
4db96cf077 HWPOISON: Add PR_MCE_KILL prctl to control early kill behaviour per process
This allows processes to override their early/late kill
behaviour on hardware memory errors.

Typically applications which are memory error aware is
better of with early kill (see the error as soon
as possible), all others with late kill (only
see the error when the error is really impacting execution)

There's a global sysctl, but this way an application
can set its specific policy.

We're using two bits, one to signify that the process
stated its intention and that

I also made the prctl future proof by enforcing
the unused arguments are 0.

The state is inherited to children.

Note this makes us officially run out of process flags
on 32bit, but the next patch can easily add another field.

Manpage patch will be supplied separately.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
2009-09-16 11:50:14 +02:00
Ingo Molnar
51e0304ce6 sched: Implement a gentler fair-sleepers feature
Add back FAIR_SLEEPERS and GENTLE_FAIR_SLEEPERS.

FAIR_SLEEPERS is the old logic: credit sleepers with their sleep time.

GENTLE_FAIR_SLEEPERS dampens this a bit: 50% of their sleep time gets
credited.

The hope here is to still give the benefits of fair-sleepers logic
(quick wakeups, etc.) while not allow them to have 100% of their
sleep time as if they were running.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-16 09:05:20 +02:00
Peter Zijlstra
59abf02644 sched: Add SD_PREFER_LOCAL
And turn it on for NUMA and MC domains. This improves
locality in balancing decisions by keeping up to
capacity amount of tasks local before looking for idle
CPUs. (and twice the capacity if SD_POWERSAVINGS_BALANCE
is set.)

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-16 08:42:40 +02:00
Jens Axboe
cb684b5bcd block: fix linkage problem with blk_iopoll and !CONFIG_BLOCK
kernel/built-in.o:(.data+0x17b0): undefined reference to `blk_iopoll_enabled'

Since the extern declaration makes the compile work, but the actual
symbol is missing when block/blk-iopoll.o isn't linked in.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-15 21:53:11 +02:00
Peter Zijlstra
e69b0f1b41 sched: Add a few SYNC hint knobs to play with
Currently we use overlap to weaken the SYNC hint, but allow it to
set the hint as well.

 echo NO_SYNC_WAKEUP > /debug/sched_features
 echo SYNC_MORE > /debug/sched_features

preserves pipe-test behaviour without using the WF_SYNC hint.

Worth playing with on more workloads...

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 19:47:23 +02:00
Peter Zijlstra
63859d4fe4 sched: Fix sync wakeups again
The sync argument rename to introduce WF_* broke stuff by missing a
local alias for an argument in __wake_up_common, fix it by using
the more descriptive wake_flags name.

This restores WF_SYNC propagation, which fixes wake_affine()
behaviour, which fixes pipe-test.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 19:47:22 +02:00
Linus Torvalds
723e9db7a4 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (134 commits)
  powerpc/nvram: Enable use Generic NVRAM driver for different size chips
  powerpc/iseries: Fix oops reading from /proc/iSeries/mf/*/cmdline
  powerpc/ps3: Workaround for flash memory I/O error
  powerpc/booke: Don't set DABR on 64-bit BookE, use DAC1 instead
  powerpc/perf_counters: Reduce stack usage of power_check_constraints
  powerpc: Fix bug where perf_counters breaks oprofile
  powerpc/85xx: Fix SMP compile error and allow NULL for smp_ops
  powerpc/irq: Improve nanodoc
  powerpc: Fix some late PowerMac G5 with PCIe ATI graphics
  powerpc/fsl-booke: Use HW PTE format if CONFIG_PTE_64BIT
  powerpc/book3e: Add missing page sizes
  powerpc/pseries: Fix to handle slb resize across migration
  powerpc/powermac: Thermal control turns system off too eagerly
  powerpc/pci: Merge ppc32 and ppc64 versions of phb_scan()
  powerpc/405ex: support cuImage via included dtb
  powerpc/405ex: provide necessary fixup function to support cuImage
  powerpc/40x: Add support for the ESTeem 195E (PPC405EP) SBC
  powerpc/44x: Add Eiger AMCC (AppliedMicro) PPC460SX evaluation board support.
  powerpc/44x: Update Arches defconfig
  powerpc/44x: Update Arches dts
  ...

Fix up conflicts in drivers/char/agp/uninorth-agp.c
2009-09-15 09:51:09 -07:00
Ming Lei
a56af87648 driver-core: move dma-coherent.c from kernel to driver/base
Placing dma-coherent.c in driver/base is better than in kernel,
since it contains code to do per-device coherent dma memory
handling.

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-15 09:50:47 -07:00
Linus Torvalds
ada3fa1505 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (46 commits)
  powerpc64: convert to dynamic percpu allocator
  sparc64: use embedding percpu first chunk allocator
  percpu: kill lpage first chunk allocator
  x86,percpu: use embedding for 64bit NUMA and page for 32bit NUMA
  percpu: update embedding first chunk allocator to handle sparse units
  percpu: use group information to allocate vmap areas sparsely
  vmalloc: implement pcpu_get_vm_areas()
  vmalloc: separate out insert_vmalloc_vm()
  percpu: add chunk->base_addr
  percpu: add pcpu_unit_offsets[]
  percpu: introduce pcpu_alloc_info and pcpu_group_info
  percpu: move pcpu_lpage_build_unit_map() and pcpul_lpage_dump_cfg() upward
  percpu: add @align to pcpu_fc_alloc_fn_t
  percpu: make @dyn_size mandatory for pcpu_setup_first_chunk()
  percpu: drop @static_size from first chunk allocators
  percpu: generalize first chunk allocator selection
  percpu: build first chunk allocators selectively
  percpu: rename 4k first chunk allocator to page
  percpu: improve boot messages
  percpu: fix pcpu_reclaim() locking
  ...

Fix trivial conflict as by Tejun Heo in kernel/sched.c
2009-09-15 09:39:44 -07:00
Linus Torvalds
f199fd9906 Merge branch 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf_counter: Fix buffer overflow in perf_copy_attr()
2009-09-15 09:34:27 -07:00
Steven Rostedt
6ca6cca31d tracing: optimize global_trace_clock cachelines
The prev_trace_clock_time is only read or written to when the
trace_clock_lock is taken. For better perfomance, they
should share the same cache line.

Reported-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-15 12:24:22 -04:00
Linus Torvalds
227423904c Merge branch 'x86-pat-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-pat-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, pat: Fix cacheflush address in change_page_attr_set_clr()
  mm: remove !NUMA condition from PAGEFLAGS_EXTENDED condition set
  x86: Fix earlyprintk=dbgp for machines without NX
  x86, pat: Sanity check remap_pfn_range for RAM region
  x86, pat: Lookup the protection from memtype list on vm_insert_pfn()
  x86, pat: Add lookup_memtype to get the current memtype of a paddr
  x86, pat: Use page flags to track memtypes of RAM pages
  x86, pat: Generalize the use of page flag PG_uncached
  x86, pat: Add rbtree to do quick lookup in memtype tracking
  x86, pat: Add PAT reserve free to io_mapping* APIs
  x86, pat: New i/f for driver to request memtype for IO regions
  x86, pat: ioremap to follow same PAT restrictions as other PAT users
  x86, pat: Keep identity maps consistent with mmaps even when pat_disabled
  x86, mtrr: make mtrr_aps_delayed_init static bool
  x86, pat/mtrr: Rendezvous all the cpus for MTRR/PAT init
  generic-ipi: Allow cpus not yet online to call smp_call_function with irqs disabled
  x86: Fix an incorrect argument of reserve_bootmem()
  x86: Fix system crash when loading with "reservetop" parameter
2009-09-15 09:19:38 -07:00
Linus Torvalds
1aaf2e5913 Merge branch 'x86-txt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-txt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, intel_txt: clean up the impact on generic code, unbreak non-x86
  x86, intel_txt: Handle ACPI_SLEEP without X86_TRAMPOLINE
  x86, intel_txt: Fix typos in Kconfig help
  x86, intel_txt: Factor out the code for S3 setup
  x86, intel_txt: tboot.c needs <asm/fixmap.h>
  intel_txt: Force IOMMU on for Intel TXT launch
  x86, intel_txt: Intel TXT Sx shutdown support
  x86, intel_txt: Intel TXT reboot/halt shutdown support
  x86, intel_txt: Intel TXT boot support
2009-09-15 09:19:20 -07:00
Ashwin Chaugule
7403f41f19 hrtimer: Eliminate needless reprogramming of clock events device
On NOHZ systems the following timers,

-  tick_nohz_restart_sched_tick (tick_sched_timer)
-  hrtimer_start (tick_sched_timer)

are reprogramming the clock events device far more often than needed.
No specific test case was required to observe this effect. This
occurres because there was no check to see if the currently removed or
restarted hrtimer was:

1) the one which previously armed the clock events device.
2) going to be replaced by another timer which has the same expiry time.

Avoid the reprogramming in hrtimer_force_reprogram when the new expiry
value which is evaluated from the clock bases is equal to
cpu_base->expires_next. This results in faster application startup
time by ~4%.

[ tglx: simplified initial solution ]

Signed-off-by: Ashwin Chaugule <ashwinc@quicinc.com>
LKML-Reference: <4AA00165.90609@codeaurora.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-09-15 17:09:44 +02:00
Peter Zijlstra
a7558e0105 sched: Add WF_FORK
Avoid the cache buddies from biasing the time distribution away
from fork()ers. Normally the next buddy will be the preferred
scheduling target, but this makes fork()s prefer to run the new
child, whereas we prefer to run the parent, since that will
generate more work.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 16:51:31 +02:00
Peter Zijlstra
7d47872146 sched: Rename sync arguments
In order to extend the functions to have more than 1 flag (sync),
rename the argument to flags, and explicitly define a WF_ space for
individual flags.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 16:51:30 +02:00
Peter Zijlstra
0763a660a8 sched: Rename select_task_rq() argument
In order to be able to rename the sync argument, we need to rename
the current flag argument.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 16:51:29 +02:00
Peter Zijlstra
8e6598af3f sched: Feature to disable APERF/MPERF cpu_power
I suspect a feed-back loop between cpuidle and the aperf/mperf
cpu_power bits, where when we have idle C-states lower the ratio,
which leads to lower cpu_power and then less load, which generates
more idle time, etc..

Put in a knob to disable it.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 16:51:28 +02:00
Peter Zijlstra
d6a59aa3a2 sched: Provide arch_scale_freq_power
Provide an ach specific hook for cpufreq based scaling of
cpu_power.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
[ego@in.ibm.com: spotting bugs]
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 16:51:24 +02:00
Mike Galbraith
0ec9fab3d1 sched: Improve latencies and throughput
Make the idle balancer more agressive, to improve a
x264 encoding workload provided by Jason Garrett-Glaser:

 NEXT_BUDDY NO_LB_BIAS
 encoded 600 frames, 252.82 fps, 22096.60 kb/s
 encoded 600 frames, 250.69 fps, 22096.60 kb/s
 encoded 600 frames, 245.76 fps, 22096.60 kb/s

 NO_NEXT_BUDDY LB_BIAS
 encoded 600 frames, 344.44 fps, 22096.60 kb/s
 encoded 600 frames, 346.66 fps, 22096.60 kb/s
 encoded 600 frames, 352.59 fps, 22096.60 kb/s

 NO_NEXT_BUDDY NO_LB_BIAS
 encoded 600 frames, 425.75 fps, 22096.60 kb/s
 encoded 600 frames, 425.45 fps, 22096.60 kb/s
 encoded 600 frames, 422.49 fps, 22096.60 kb/s

Peter pointed out that this is better done via newidle_idx,
not via LB_BIAS, newidle balancing should look for where
there is load _now_, not where there was load 2 ticks ago.

Worst-case latencies are improved as well as no buddies
means less vruntime spread. (as per prior lkml discussions)

This change improves kbuild-peak parallelism as well.

Reported-by: Jason Garrett-Glaser <darkshikari@gmail.com>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1253011667.9128.16.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 16:51:16 +02:00
Peter Zijlstra
78e7ed53c9 sched: Tweak wake_idx
When merging select_task_rq_fair() and sched_balance_self() we lost
the use of wake_idx, restore that and set them to 0 to make wake
balancing more aggressive.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 16:01:07 +02:00
Peter Zijlstra
d7c33c4930 sched: Fix task affinity for select_task_rq_fair
While merging select_task_rq_fair() and sched_balance_self() I made
a mistake that leads to testing the wrong task affinty.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 16:01:07 +02:00
Peter Zijlstra
83f54960c1 sched: for_each_domain() vs RCU
for_each_domain() uses RCU to serialize the sched_domains, except
it doesn't actually use rcu_read_lock() and instead relies on
disabling preemption -> FAIL.

XXX: audit other sched_domain code.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 16:01:06 +02:00
Peter Zijlstra
ae154be1f3 sched: Weaken SD_POWERSAVINGS_BALANCE
One of the problems of power-saving balancing is that under certain
scenarios it is too slow and allows tons of real work to pile up.

Avoid this by ignoring the powersave stuff when there's real work
to be done.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 16:01:06 +02:00
Peter Zijlstra
c88d591089 sched: Merge select_task_rq_fair() and sched_balance_self()
The problem with wake_idle() is that is doesn't respect things like
cpu_power, which means it doesn't deal well with SMT nor the recent
RT interaction.

To cure this, it needs to do what sched_balance_self() does, which
leads to the possibility of merging select_task_rq_fair() and
sched_balance_self().

Modify sched_balance_self() to:

  - update_shares() when walking up the domain tree,
    (it only called it for the top domain, but it should
     have done this anyway), which allows us to remove
    this ugly bit from try_to_wake_up().

  - do wake_affine() on the smallest domain that contains
    both this (the waking) and the prev (the wakee) cpu for
    WAKE invocations.

Then use the top-down balance steps it had to replace wake_idle().

This leads to the dissapearance of SD_WAKE_BALANCE and
SD_WAKE_IDLE_FAR, with SD_WAKE_IDLE replaced with SD_BALANCE_WAKE.

SD_WAKE_AFFINE needs SD_BALANCE_WAKE to be effective.

Touch all topology bits to replace the old with new SD flags --
platforms might need re-tuning, enabling SD_BALANCE_WAKE
conditionally on a NUMA distance seems like a good additional
feature, magny-core and small nehalem systems would want this
enabled, systems with slow interconnects would not.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 16:01:05 +02:00
Peter Zijlstra
e9c8431185 sched: Add TASK_WAKING
We're going to want to drop rq->lock in try_to_wake_up() for a
longer period of time, however we also want to deal with concurrent
waking of the same task, which is currently handled by holding
rq->lock.

So introduce a new TASK state, namely TASK_WAKING, which indicates
someone is already waking the task (other wakers will fail p->state
& state).

We also keep preemption disabled over the whole ttwu().

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 16:01:05 +02:00
Peter Zijlstra
5f3edc1b1e sched: Hook sched_balance_self() into sched_class::select_task_rq()
Rather ugly patch to fully place the sched_balance_self() code
inside the fair class.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 16:01:04 +02:00
Peter Zijlstra
aaee1203ca sched: Move sched_balance_self() into sched_fair.c
Move the sched_balance_self() code into sched_fair.c

This facilitates the merger of sched_balance_self() and
sched_fair::select_task_rq().

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 16:01:04 +02:00
Peter Zijlstra
f5f08f39ee sched: Move code around
In preparation to other code movement, move weighted_cpuload(),
source_load() and target_load() before the class includes.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 16:01:03 +02:00
Peter Zijlstra
e26af0e8b2 sched: Add come comments to the sched features
Add text...

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 16:01:03 +02:00
Mike Galbraith
3cb63d527f sched: Complete buddy switches
Add a NEXT_BUDDY feature flag to aid in debugging.

Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 16:01:02 +02:00
Peter Zijlstra
e6b1b2c9c0 sched: Split WAKEUP_OVERLAP
It consists of two conditions, split them out in separate toggles
so we can test them independently.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 16:01:02 +02:00
Peter Zijlstra
b78bb868c5 sched: Fix double_rq_lock() compile warning
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 16:01:01 +02:00
Thomas Gleixner
12e09337fe time: Prevent 32 bit overflow with set_normalized_timespec()
set_normalized_timespec() nsec argument is of type long. The recent
timekeeping changes of ktime_get_ts() feed 

	ts->tv_nsec + tomono.tv_nsec + nsecs

to set_normalized_timespec(). On 32 bit machines that sum can be
larger than (1 << 31) and therefor result in a negative value which
screws up the result completely.

Make the nsec argument of set_normalized_timespec() s64 to fix the
problem at hand. This also prevents similar problems for future users
of set_normalized_timespec().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Carsten Emde <carsten.emde@osadl.org>
LKML-Reference: <new-submission>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: John Stultz <johnstul@us.ibm.com>
2009-09-15 10:17:30 +02:00
Xiao Guangrong
b3e62e3505 perf_counter: Fix buffer overflow in perf_copy_attr()
If we pass a big size data over perf_counter_open() syscall,
the kernel will copy this data to a small buffer, it will
cause kernel crash.

This bug makes the kernel unsafe and non-root local user can
trigger it.

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Paul Mackerras <paulus@samba.org>
Cc: <stable@kernel.org>
LKML-Reference: <4AAF37D4.5010706@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-15 09:53:31 +02:00
Linus Torvalds
1824090496 Merge branch 'for-linus3' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6
* 'for-linus3' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
  SELinux: inline selinux_is_enabled in !CONFIG_SECURITY_SELINUX
  KEYS: Fix garbage collector
  KEYS: Unlock tasklist when exiting early from keyctl_session_to_parent
  CRED: Allow put_cred() to cope with a NULL groups list
  SELinux: flush the avc before disabling SELinux
  SELinux: seperate avc_cache flushing
  Creds: creds->security can be NULL is selinux is disabled
2009-09-14 20:07:31 -07:00
Linus Torvalds
f86054c245 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6: (23 commits)
  at_hdmac: Rework suspend_late()/resume_early()
  PM: Reset transition_started at dpm_resume_noirq
  PM: Update kerneldoc comments in drivers/base/power/main.c
  PM: Add convenience macro to make switching to dev_pm_ops less error-prone
  hp-wmi: Switch driver to dev_pm_ops
  floppy: Switch driver to dev_pm_ops
  PM: Trivial fixes
  PM / Hibernate / Memory hotplug: Always use for_each_populated_zone()
  PM/Hibernate: Do not try to allocate too much memory too hard (rev. 2)
  PM/Hibernate: Do not release preallocated memory unnecessarily (rev. 2)
  PM/Hibernate: Rework shrinking of memory
  PM: Fix typo in label name s/Platofrm_finish/Platform_finish/
  PM: Run-time PM platform device bus support
  PM: Introduce core framework for run-time PM of I/O devices (rev. 17)
  Driver Core: Make PM operations a const pointer
  PM: Remove platform device suspend_late()/resume_early() V2
  USB: Rework musb suspend()/resume_early()
  I2C: Rework i2c-s3c2410 suspend_late()/resume() V2
  I2C: Rework i2c-pxa suspend_late()/resume_early()
  DMA: Rework txx9dmac suspend_late()/resume_early()
  ...

Fix trivial conflict in drivers/base/platform.c (due to same
constification patch being merged in both sides, along with some other
PM work in the PM branch)
2009-09-14 20:03:54 -07:00
Linus Torvalds
c91d7d54ea Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-kconfig
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-kconfig:
  kconfig: add missing dependency of conf to localyesconfig
  kconfig: test if a .config already exists
  kconfig: make local .config default for streamline_config
  kconfig: test for /boot/config-uname after /proc/config.gz in localconfig
  kconfig: unset IKCONFIG_PROC and clean up nesting
  kconfig: search for a config to base the local(mod|yes)config on
  kconfig: keep config.gz around even if CONFIG_IKCONFIG_PROC is not set
  kconfig: have extract-ikconfig read ELF files
  kconfig: add check if end exists in extract-ikconfig
  kconfig: enable CONFIG_IKCONFIG from streamline_config.pl
  kconfig: do not warn about modules built in
  kconfig: streamline_config.pl do not stop with no depends
  kconfig: add make localyesconfig option
  kconfig: make localmodconfig to run streamline_config.pl
  kconfig: add streamline_config.pl to scripts
2009-09-14 19:59:37 -07:00
Mike Frysinger
555f386c98 ftrace: document function and function graph implementation
While implementing function tracer and function tracer graph support,
I found the exact arch implementation details to be a bit lacking
(and my x86 foo ain't great).  So after pounding out support for
the Blackfin arch, start documenting the requirements/details.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
LKML-Reference: <1252973415-21264-1-git-send-email-vapier@gentoo.org>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-14 21:43:15 -04:00
Linus Torvalds
355bbd8cb8 Merge branch 'for-2.6.32' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.32' of git://git.kernel.dk/linux-2.6-block: (29 commits)
  block: use blkdev_issue_discard in blk_ioctl_discard
  Make DISCARD_BARRIER and DISCARD_NOBARRIER writes instead of reads
  block: don't assume device has a request list backing in nr_requests store
  block: Optimal I/O limit wrapper
  cfq: choose a new next_req when a request is dispatched
  Seperate read and write statistics of in_flight requests
  aoe: end barrier bios with EOPNOTSUPP
  block: trace bio queueing trial only when it occurs
  block: enable rq CPU completion affinity by default
  cfq: fix the log message after dispatched a request
  block: use printk_once
  cciss: memory leak in cciss_init_one()
  splice: update mtime and atime on files
  block: make blk_iopoll_prep_sched() follow normal 0/1 return convention
  cfq-iosched: get rid of must_alloc flag
  block: use interrupts disabled version of raise_softirq_irqoff()
  block: fix comment in blk-iopoll.c
  block: adjust default budget for blk-iopoll
  block: fix long lines in block/blk-iopoll.c
  block: add blk-iopoll, a NAPI like approach for block devices
  ...
2009-09-14 17:55:15 -07:00
Anirban Sinha
353f6dd2de cleanup console_print()
console_print() is an old legacy interface mostly unused in the entire
kernel tree. It's best to clean up its existing use and let developers
use their own implementation of it as they feel fit.

Signed-off-by: Anirban Sinha <asinha@zeugmasystems.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-14 17:41:42 -07:00
David Howells
4a5d6ba191 CRED: Allow put_cred() to cope with a NULL groups list
put_cred() will oops if given a NULL groups list, but that is now possible with
the existence of cred_alloc_blank(), as used in keyctl_session_to_parent().

Added in commit:

	commit ee18d64c1f
	Author: David Howells <dhowells@redhat.com>
	Date:   Wed Sep 2 09:14:21 2009 +0100
	KEYS: Add a keyctl to install a process's session keyring on its parent [try #6]

Reported-by: Marc Dionne <marc.c.dionne@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-09-15 09:10:57 +10:00
Thomas Gleixner
54a6bc0b07 clocksource: Delay clocksource down rating to late boot
The down rating of clock sources in the early boot process via the
clock source watchdog mechanism can happen way before the per cpu
event queues are initialized. This leads to a boot crash on x86 when
the TSC is marked unstable in the SMP bring up.

The selection of a clock source for time keeping happens in the late
boot process so we can safely delay the list manipulation until
clocksource_done_booting() is called.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <new-submission>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-14 21:59:32 +02:00
Thomas Gleixner
e6c733050f clocksource: clocksource_select must be called with mutex locked
The callers of clocksource_select must hold clocksource_mutex to
protect the clocksource_list.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <new-submission>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-14 21:59:32 +02:00
Wu Fengguang
8de0307326 PM: Trivial fixes
Fix the definition of BM_BITS_PER_BLOCK and kerneldoc
description of create_bm_block_list().

[rjw: Added changelog.]

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-09-14 20:26:59 +02:00
Gerald Schaefer
98e73dc5d2 PM / Hibernate / Memory hotplug: Always use for_each_populated_zone()
Use for_each_populated_zone() instead of for_each_zone() in hibernation
code. This fixes a bug on s390, where we allow both config options
HIBERNATION and MEMORY_HOTPLUG, so that we also have a ZONE_MOVABLE
here. We only allow hibernation if no memory hotplug operation was
performed, so in fact both features can only be used exclusively, but
this way we don't need 2 differently configured (distribution) kernels.

If we have an unpopulated ZONE_MOVABLE, we allow hibernation but run
into a BUG_ON() in memory_bm_test/set/clear_bit() because hibernation
code iterates through all zones, not only the populated zones, in
several places. For example, swsusp_free() does for_each_zone() and
then checks for pfn_valid(), which is true even if the zone is not
populated, resulting in a BUG_ON() later because the pfn cannot be
found in the memory bitmap.

Replacing all occurences of for_each_zone() in hibernation code with
for_each_populated_zone() would fix this issue.

[rjw: Rebased on top of linux-next hibernation patches.]

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-09-14 20:26:59 +02:00
Rafael J. Wysocki
ef4aede3f1 PM/Hibernate: Do not try to allocate too much memory too hard (rev. 2)
We want to avoid attempting to free too much memory too hard during
hibernation, so estimate the minimum size of the image to use as the
lower limit for preallocating memory.

The approach here is based on the (experimental) observation that we
can't free more page frames than the sum of:

* global_page_state(NR_SLAB_RECLAIMABLE)
* global_page_state(NR_ACTIVE_ANON)
* global_page_state(NR_INACTIVE_ANON)
* global_page_state(NR_ACTIVE_FILE)
* global_page_state(NR_INACTIVE_FILE)

minus

* global_page_state(NR_FILE_MAPPED)

Namely, if this number is subtracted from the number of saveable
pages in the system, we get a good estimate of the minimum reasonable
size of a hibernation image.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Wu Fengguang <fengguang.wu@intel.com>
2009-09-14 20:26:59 +02:00
Rafael J. Wysocki
64a473cb74 PM/Hibernate: Do not release preallocated memory unnecessarily (rev. 2)
Since the hibernation code is now going to use allocations of memory
to make enough room for the image, it can also use the page frames
allocated at this stage as image page frames.  The low-level
hibernation code needs to be rearranged for this purpose, but it
allows us to avoid freeing a great number of pages and allocating
these same pages once again later, so it generally is worth doing.

[rev. 2: Take highmem into account correctly.]

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-09-14 20:26:58 +02:00
Rafael J. Wysocki
4bb334353e PM/Hibernate: Rework shrinking of memory
Rework swsusp_shrink_memory() so that it calls shrink_all_memory()
just once to make some room for the image and then allocates memory
to apply more pressure to the memory management subsystem, if
necessary.

Unfortunately, we don't seem to be able to drop shrink_all_memory()
entirely just yet, because that would lead to huge performance
regressions in some test cases.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
2009-09-14 20:26:58 +02:00
Thadeu Lima de Souza Cascardo
e681c9dd62 PM: Fix typo in label name s/Platofrm_finish/Platform_finish/
Although the same label name is used somewhere else in the file, this
particular label was consistently typoed in all of its uses.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2009-09-14 20:26:58 +02:00
Rafael J. Wysocki
ac8d513a68 Merge branch 'master' into for-linus 2009-09-14 20:26:05 +02:00
Linus Torvalds
d7e9660ad9 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1623 commits)
  netxen: update copyright
  netxen: fix tx timeout recovery
  netxen: fix file firmware leak
  netxen: improve pci memory access
  netxen: change firmware write size
  tg3: Fix return ring size breakage
  netxen: build fix for INET=n
  cdc-phonet: autoconfigure Phonet address
  Phonet: back-end for autoconfigured addresses
  Phonet: fix netlink address dump error handling
  ipv6: Add IFA_F_DADFAILED flag
  net: Add DEVTYPE support for Ethernet based devices
  mv643xx_eth.c: remove unused txq_set_wrr()
  ucc_geth: Fix hangs after switching from full to half duplex
  ucc_geth: Rearrange some code to avoid forward declarations
  phy/marvell: Make non-aneg speed/duplex forcing work for 88E1111 PHYs
  drivers/net/phy: introduce missing kfree
  drivers/net/wan: introduce missing kfree
  net: force bridge module(s) to be GPL
  Subject: [PATCH] appletalk: Fix skb leak when ipddp interface is not loaded
  ...

Fixed up trivial conflicts:

 - arch/x86/include/asm/socket.h

   converted to <asm-generic/socket.h> in the x86 tree.  The generic
   header has the same new #define's, so that works out fine.

 - drivers/net/tun.c

   fix conflict between 89f56d1e9 ("tun: reuse struct sock fields") that
   switched over to using 'tun->socket.sk' instead of the redundantly
   available (and thus removed) 'tun->sk', and 2b980dbd ("lsm: Add hooks
   to the TUN driver") which added a new 'tun->sk' use.

   Noted in 'next' by Stephen Rothwell.
2009-09-14 10:37:28 -07:00
Steven Rostedt
1f5a6b4541 tracing: make testing syscall events a separate configuration
Parag noticed that the number of event tests has increased tremendously:

grep "Testing event" dmesg.31rc9 |wc -l
100

grep "Testing event" dmesg.31git |wc -l
1172

This is due to the testing of every syscall event when ftrace self
test is enabled. This adds a bit more time to kernel boot up and can
affect development by slowing down the time it takes between reboots.

This option makes the testing of the syscall events into a separate
config, to still be able to test most of ftrace internals at boot up
but not have to wait for all the syscall events to be tested.

The syscall event testing only tests the enabling and disabling of
the trace point, since the syscalls are not executed. What really needs
to be done is to somehow have a userspace tool test the syscall tracepoints
as well.

Reported-by: Parag Warudkar <parag.lkml@gmail.com>
LKML-Reference: <f7848160909130815l3e768a30n3b28808bbe5c254b@mail.gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-14 11:58:24 -04:00
Li Zefan
20a58a7723 tracing: remove some unused macros
- remove FTRACE_ENTRY_STRUCT_ONLY()
- remove TRACE_XXX() macros

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4AADF6E6.3080606@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-14 11:43:24 -04:00
Li Zefan
05ffa2d020 ftrace: add compile-time check on F_printk()
Make sure F_printk() has corrent format and args, and make sure
changes in F_STRUCT() won't break F_printk().

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4AADF6CC.1060809@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-14 11:42:10 -04:00
Li Zefan
c16de8fd7a tracing: fix F_printk() typos
I found some typos in F_printk(), so I wrote compile-time check
for it, and triggered some compile errors and warnings.

I've fixed them on x86_32, but I have no x86_64 in my hand, so there
may still be some compile warnings on 64bits.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4AADF60B.5070407@cn.fujitsu.com>

[ tested on x86_64, and works fine ]

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-14 11:40:59 -04:00
Steven Rostedt
ec827c7ece tracing: add static to generated TRACE_EVENT functions
Some of the generated functions used in the TRACE_EVENT macros are
not declared static, but they are not global.

Discovered by sparse.

Reported-by: Jaswinder Singh Rajput <jaswinder@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-14 10:50:23 -04:00
Steven Rostedt
08a4081617 ring-buffer: typecast cmpxchg to fix PowerPC warning
The cmpxchg used by PowerPC does the following:

  ({									 \
     __typeof__(*(ptr)) _o_ = (o);					 \
     __typeof__(*(ptr)) _n_ = (n);					 \
     (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_,		 \
				    (unsigned long)_n_, sizeof(*(ptr))); \
  })

This does a type check of *ptr to both o and n.

Unfortunately, the code in ring-buffer.c assigns longs to pointers
and pointers to longs and causes a warning on PowerPC:

ring_buffer.c: In function 'rb_head_page_set':
ring_buffer.c:704: warning: initialization makes pointer from integer without a cast
ring_buffer.c:704: warning: initialization makes pointer from integer without a cast
ring_buffer.c: In function 'rb_head_page_replace':
ring_buffer.c:797: warning: initialization makes integer from pointer without a cast

This patch adds the typecasts inside cmpxchg to annotate that a long is
being cast to a pointer and a pointer is being casted to a long and this
removes the PowerPC warnings.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-14 09:41:57 -04:00
Ingo Molnar
f977bb4937 perf_counter, sched: Add sched_stat_runtime tracepoint
This allows more precise tracking of how the scheduler accounts
(and acts upon) a task having spent N nanoseconds of CPU time.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-13 18:17:28 +02:00
Ingo Molnar
459ec28ab4 perf_counter: Allow mmap if paranoid checks are turned off
Before:

  $ perf sched record -f sleep 1
  Error: failed to mmap with 1 (Operation not permitted)

After:

  $ perf sched record -f sleep 1
  [ perf record: Captured and wrote 0.095 MB perf.data (~4161 samples) ]

Note, this is only allowed if perfcounter_paranoid is set to
the most permissive (non-default) value of -1.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-13 17:33:44 +02:00
Steven Rostedt
60ba770227 tracing: add filter event logic to special, mmiotrace and boot tracers
Now that the pluging tracers use macros to create the structures and
automate the exporting of their formats to the format files, they also
automatically get a filter file.

This patch adds the code to implement the filter logic in the trace
recordings.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-12 23:34:04 -04:00
Steven Rostedt
51df5fcbc1 tracing: remove trace_event_types.h
The macros in trace_entries.h have made the code in trace_event_types.h
obsolete. The file is no longer used, so this patch removes it.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-12 23:08:11 -04:00
Steven Rostedt
4e5292ea1a tracing: use the new trace_entries.h to create format files
This patch changes the way the format files in

  debugfs/tracing/events/ftrace/*/format

are created. It uses the new trace_entries.h file to automate the
creation of the format files to ensure that they are always in sync
with the actual structures. This is the same methodology used to
create the format files for the TRACE_EVENT macro.

This also updates the filter creation that was built on the creation
of the format files.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-12 23:08:10 -04:00
Steven Rostedt
d73150943c tracing: show details of structures within the ftrace structures
Some of the internal ftrace structures use structures within. The
output of a field saying it is just a structure is useless for a format
file. A binary reader of the ring buffer needs to know more about
how the fields are broken up.

This patch adds to the ftrace structure macros new fields to
describe the structures inside a structure.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-12 23:08:07 -04:00
Steven Rostedt
0a1c49db8d tracing: use macros to create internal ftrace entry ring buffer structures
The entries used by ftrace internal code (plugins) currently have their
formats manually exported to userspace. That is, the format files in
debugfs/tracing/events/ftrace/*/format are currently created by hand.
This is a maintenance nightmare, and can easily become out of sync
with what is actually shown.

This patch uses the methodology of the TRACE_EVENT macros to build
the structures so that their formats can be automated and this
will keep the structures in sync with what users can see.

This patch only changes the way the structures are created. Further
patches will build off of this to automate the format files.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-12 23:08:06 -04:00
Li Zefan
558e6547e4 tracing/profile: fix profile_disable vs module_unload
If the correspoding module is unloaded before ftrace_profile_disable()
is called, event->profile_disable() won't be called, which can
cause oops:

  # insmod trace-events-sample.ko
  # perf record -f -a -e sample:foo_bar sleep 3 &
  # sleep 1
  # rmmod trace_events_sample
  # insmod trace-events-sample.ko
  OOPS!

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4A9214E3.2070807@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-12 22:28:38 -04:00
Carsten Emde
b5130b1e7d tracing: do not update tracing_max_latency when tracer is stopped
The state of the function pair tracing_stop()/tracing_start() is
correctly considered when tracer data are updated. However, the global
and externally accessible variable tracing_max_latency is always updated
- even when tracing is stopped.

The update should only occur, if tracing was not stopped.

Signed-off-by: Carsten Emde <C.Emde@osadl.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-12 21:45:17 -04:00
Carsten Emde
41dfba4367 tracing: remove unused local variables in tracer probe functions
When the nsecs_to_usecs() conversion in probe_wakeup_sched_switch() and
check_critical_timing() was moved to a later stage in order to avoid
unnecessary computing, it was overlooked to remove the original
variables, assignments and comments..

Signed-off-by: Carsten Emde <C.Emde@osadl.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-12 21:44:13 -04:00
Linus Torvalds
483e3cd6a3 Merge branch 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (105 commits)
  ring-buffer: only enable ring_buffer_swap_cpu when needed
  ring-buffer: check for swapped buffers in start of committing
  tracing: report error in trace if we fail to swap latency buffer
  tracing: add trace_array_printk for internal tracers to use
  tracing: pass around ring buffer instead of tracer
  tracing: make tracing_reset safe for external use
  tracing: use timestamp to determine start of latency traces
  tracing: Remove mentioning of legacy latency_trace file from documentation
  tracing/filters: Defer pred allocation, fix memory leak
  tracing: remove users of tracing_reset
  tracing: disable buffers and synchronize_sched before resetting
  tracing: disable update max tracer while reading trace
  tracing: print out start and stop in latency traces
  ring-buffer: disable all cpu buffers when one finds a problem
  ring-buffer: do not count discarded events
  ring-buffer: remove ring_buffer_event_discard
  ring-buffer: fix ring_buffer_read crossing pages
  ring-buffer: remove unnecessary cpu_relax
  ring-buffer: do not swap buffers during a commit
  ring-buffer: do not reset while in a commit
  ...
2009-09-11 13:24:03 -07:00
Linus Torvalds
774a694f8c Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (64 commits)
  sched: Fix sched::sched_stat_wait tracepoint field
  sched: Disable NEW_FAIR_SLEEPERS for now
  sched: Keep kthreads at default priority
  sched: Re-tune the scheduler latency defaults to decrease worst-case latencies
  sched: Turn off child_runs_first
  sched: Ensure that a child can't gain time over it's parent after fork()
  sched: enable SD_WAKE_IDLE
  sched: Deal with low-load in wake_affine()
  sched: Remove short cut from select_task_rq_fair()
  sched: Turn on SD_BALANCE_NEWIDLE
  sched: Clean up topology.h
  sched: Fix dynamic power-balancing crash
  sched: Remove reciprocal for cpu_power
  sched: Try to deal with low capacity, fix update_sd_power_savings_stats()
  sched: Try to deal with low capacity
  sched: Scale down cpu_power due to RT tasks
  sched: Implement dynamic cpu_power
  sched: Add smt_gain
  sched: Update the cpu_power sum during load-balance
  sched: Add SD_PREFER_SIBLING
  ...
2009-09-11 13:23:18 -07:00
Linus Torvalds
4f0ac85416 Merge branch 'perfcounters-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perfcounters-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (60 commits)
  perf tools: Avoid unnecessary work in directory lookups
  perf stat: Clean up statistics calculations a bit more
  perf stat: More advanced variance computation
  perf stat: Use stddev_mean in stead of stddev
  perf stat: Remove the limit on repeat
  perf stat: Change noise calculation to use stddev
  x86, perf_counter, bts: Do not allow kernel BTS tracing for now
  x86, perf_counter, bts: Correct pointer-to-u64 casts
  x86, perf_counter, bts: Fail if BTS is not available
  perf_counter: Fix output-sharing error path
  perf trace: Fix read_string()
  perf trace: Print out in nanoseconds
  perf tools: Seek to the end of the header area
  perf trace: Fix parsing of perf.data
  perf trace: Sample timestamps as well
  perf_counter: Introduce new (non-)paranoia level to allow raw tracepoint access
  perf trace: Sample the CPU too
  perf tools: Work around strict aliasing related warnings
  perf tools: Clean up warnings list in the Makefile
  perf tools: Complete support for dynamic strings
  ...
2009-09-11 13:22:43 -07:00
Linus Torvalds
d90a7e8640 Merge branch 'irq-threaded-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'irq-threaded-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  genirq: Do not mask oneshot edge type interrupts
  genirq: Support nested threaded irq handling
  genirq: Add buslock support
  genirq: Add oneshot support
2009-09-11 13:21:31 -07:00
Linus Torvalds
12a499612e Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  pci/intr_remapping: Allocate irq_iommu on node
  irq: Add irq_node() primitive
  irq: Make sure irq_desc for legacy irq get correct node setting
  genirq: Add prototype for handle_nested_irq()
  irq: Remove superfluous NULL pointer check in check_irq_resend()
  irq: Clean up by removing irqfixup MODULE_PARM_DESC()
  genirq: Fix comment describing suspend_device_irqs()
  genirq: Remove obsolete defines and typedefs
2009-09-11 13:20:42 -07:00
Linus Torvalds
eee2775d99 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (28 commits)
  rcu: Move end of special early-boot RCU operation earlier
  rcu: Changes from reviews: avoid casts, fix/add warnings, improve comments
  rcu: Create rcutree plugins to handle hotplug CPU for multi-level trees
  rcu: Remove lockdep annotations from RCU's _notrace() API members
  rcu: Add #ifdef to suppress __rcu_offline_cpu() warning in !HOTPLUG_CPU builds
  rcu: Add CPU-offline processing for single-node configurations
  rcu: Add "notrace" to RCU function headers used by ftrace
  rcu: Remove CONFIG_PREEMPT_RCU
  rcu: Merge preemptable-RCU functionality into hierarchical RCU
  rcu: Simplify rcu_pending()/rcu_check_callbacks() API
  rcu: Use debugfs_remove_recursive() simplify code.
  rcu: Merge per-RCU-flavor initialization into pre-existing macro
  rcu: Fix online/offline indication for rcudata.csv trace file
  rcu: Consolidate sparse and lockdep declarations in include/linux/rcupdate.h
  rcu: Renamings to increase RCU clarity
  rcu: Move private definitions from include/linux/rcutree.h to kernel/rcutree.h
  rcu: Expunge lingering references to CONFIG_CLASSIC_RCU, optimize on !SMP
  rcu: Delay rcu_barrier() wait until beginning of next CPU-hotunplug operation.
  rcu: Fix typo in rcu_irq_exit() comment header
  rcu: Make rcupreempt_trace.c look at offline CPUs
  ...
2009-09-11 13:20:18 -07:00
Linus Torvalds
53e16fbd30 Merge branch 'core-printk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-printk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  printk: Fix "printk: Enable the use of more than one CON_BOOT (early console)"
  printk: Restore previous console_loglevel when re-enabling logging
  printk: Ensure that "console enabled" messages are printed on the console
  printk: Enable the use of more than one CON_BOOT (early console)
2009-09-11 13:19:40 -07:00
Linus Torvalds
4e3408d9f7 Merge branch 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (32 commits)
  locking, m68k/asm-offsets: Rename signal defines
  locking: Inline spinlock code for all locking variants on s390
  locking: Simplify spinlock inlining
  locking: Allow arch-inlined spinlocks
  locking: Move spinlock function bodies to header file
  locking, m68k: Calculate thread_info offset with asm offset
  locking, m68k/asm-offsets: Rename pt_regs offset defines
  locking, sparc: Rename __spin_try_lock() and friends
  locking, powerpc: Rename __spin_try_lock() and friends
  lockdep: Remove recursion stattistics
  lockdep: Simplify lock_stat seqfile code
  lockdep: Simplify lockdep_chains seqfile code
  lockdep: Simplify lockdep seqfile code
  lockdep: Fix missing entries in /proc/lock_chains
  lockdep: Fix missing entry in /proc/lock_stat
  lockdep: Fix memory usage info of BFS
  lockdep: Reintroduce generation count to make BFS faster
  lockdep: Deal with many similar locks
  lockdep: Introduce lockdep_assert_held()
  lockdep: Fix style nits
  ...
2009-09-11 13:17:24 -07:00
Linus Torvalds
7193bea53f Merge branch 'core-futexes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-futexes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  futex: Detect mismatched requeue targets
  futex: Correct futex_wait_requeue_pi() commentary
2009-09-11 13:16:22 -07:00
Linus Torvalds
989aa44a5f Merge branch 'core-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  debug lockups: Improve lockup detection, fix generic arch fallback
  debug lockups: Improve lockup detection
2009-09-11 13:15:55 -07:00
Linus Torvalds
4004f02d7a Merge branch 'core-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  workqueues: Improve schedule_work() documentation
2009-09-11 13:13:32 -07:00
jolsa@redhat.com
689fd8b65d tracing: trace parser support for function and graph
Convert the writing to 'set_graph_function', 'set_ftrace_filter'
and 'set_ftrace_notrace' to use the generic trace_parser
'trace_get_user' function.

Removed FTRACE_ITER_CONT flag, since it's not needed after this change.

Minor fix in set_graph_function display - g_show function.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
LKML-Reference: <1252682969-3366-4-git-send-email-jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-11 15:20:18 -04:00
jolsa@redhat.com
489663644c tracing: trace parser support for set_event
Convert the parsing of the file 'set_event' to use the generic
trace_praser 'trace_get_user' function.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
LKML-Reference: <1252682969-3366-3-git-send-email-jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-11 14:47:11 -04:00
jolsa@redhat.com
b63f39ea50 tracing: create generic trace parser
Create a "trace_parser" that can parse the user space input for
separate words.

struct trace_parser is the descriptor.

Generic "trace_get_user" function that can be a helper to read multiple
words passed in by user space.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
LKML-Reference: <1252682969-3366-2-git-send-email-jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-11 14:46:55 -04:00
Steven Rostedt
f81c972d27 tracing: consolidate code between trace_output.c and trace_function_graph.c
Both trace_output.c and trace_function_graph.c do basically the same
thing to handle the printing of the latency-format. This patch moves
the code into one function that both can use.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-11 14:24:13 -04:00
Martin Schwidefsky
f79e0258ea clocksource: Resolve cpu hotplug dead lock with TSC unstable, fix crash
The watchdog timer is started after the watchdog clocksource
and at least one watched clocksource have been registered. The
clocksource work element watchdog_work is initialized just
before the clocksource timer is started. This is too late for
the clocksource_mark_unstable call from native_cpu_up. To fix
this use a static initializer for watchdog_work.

This resolves a boot crash reported by multiple people.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: John Stultz <johnstul@us.ibm.com>
LKML-Reference: <20090911153305.3fe9a361@skybase>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-11 20:17:18 +02:00
Steven Rostedt
637e7e8641 tracing: add lock depth to entries
This patch adds the lock depth of the big kernel lock to the generic
entry header. This way we can see the depth of the lock and help
in removing the BKL.

Example:

 #                  _------=> CPU#
 #                 / _-----=> irqs-off
 #                | / _----=> need-resched
 #                || / _---=> hardirq/softirq
 #                ||| / _--=> preempt-depth
 #                |||| /_--=> lock-depth
 #                |||||/     delay
 #  cmd     pid   |||||| time  |   caller
 #     \   /      ||||||   \   |   /
   <idle>-0       2.N..3 5902255250us+: lock_acquire: read rcu_read_lock
   <idle>-0       2.N..3 5902255253us+: lock_release: rcu_read_lock
   <idle>-0       2dN..3 5902255257us+: lock_acquire: xtime_lock
   <idle>-0       2dN..4 5902255259us : lock_acquire: clocksource_lock
   <idle>-0       2dN..4 5902255261us+: lock_release: clocksource_lock

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-11 13:55:35 -04:00
Linus Torvalds
a12e4d304c Merge branch 'writeback' of git://git.kernel.dk/linux-2.6-block
* 'writeback' of git://git.kernel.dk/linux-2.6-block:
  writeback: check for registered bdi in flusher add and inode dirty
  writeback: add name to backing_dev_info
  writeback: add some debug inode list counters to bdi stats
  writeback: get rid of pdflush completely
  writeback: switch to per-bdi threads for flushing data
  writeback: move dirty inodes from super_block to backing_dev_info
  writeback: get rid of generic_sync_sb_inodes() export
2009-09-11 09:17:05 -07:00
Steven Rostedt
48659d3119 tracing: move tgid out of generic entry and into userstack
The userstack trace required the recording of the tgid entry.
Unfortunately, it was added to the generic entry where it wasted
4 bytes of every entry and was only used by one entry.

This patch moves it out of the generic field and moves it into the
only user (userstack_entry).

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-11 11:36:23 -04:00
Steven Rostedt
49ff590390 tracing: add latency format to function_graph tracer
While debugging something with the function_graph tracer, I found the
need to see the preempt count of the traces. Unfortunately, since
the function graph tracer has its own output formatting, it does not
honor the latency-format option.

This patch makes the function_graph tracer honor the latency-format
option, but still keeps control of the output. But now we have the
same details that the latency-format supplies.

 # tracer: function_graph
 #
 #      _-----=> irqs-off
 #     / _----=> need-resched
 #    | / _---=> hardirq/softirq
 #    || / _--=> preempt-depth
 #    ||| /
 #    ||||
 # CPU||||  DURATION                  FUNCTION CALLS
 # |  ||||   |   |                     |   |   |   |
  3)  d..1  1.333 us    |        idle_cpu();
  3)  d.h1              |        tick_check_idle() {
  3)  d.h1  0.550 us    |          tick_check_oneshot_broadcast();
  3)  d.h1              |          tick_nohz_stop_idle() {
  3)  d.h1              |            ktime_get() {
  3)  d.h1              |              ktime_get_ts() {

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-11 10:59:49 -04:00
Jens Axboe
5e605b64a1 block: add blk-iopoll, a NAPI like approach for block devices
This borrows some code from NAPI and implements a polled completion
mode for block devices. The idea is the same as NAPI - instead of
doing the command completion when the irq occurs, schedule a dedicated
softirq in the hopes that we will complete more IO when the iopoll
handler is invoked. Devices have a budget of commands assigned, and will
stay in polled mode as long as they continue to consume their budget
from the iopoll softirq handler. If they do not, the device is set back
to interrupt completion mode.

This patch holds the core bits for blk-iopoll, device driver support
sold separately.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-11 14:33:31 +02:00
Jens Axboe
d993831fa7 writeback: add name to backing_dev_info
This enables us to track who does what and print info. Its main use
is catching dirty inodes on the default_backing_dev_info, so we can
fix that up.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-11 09:20:26 +02:00
Masami Hiramatsu
6e9f23d161 tracing/kprobes: Show event name in trace output
Show event name in tracing/trace output. This also fixes kprobes events
format to comply with other tracepoint events formats.

Before patching:
<...>-1447  [001] 1038282.286875: do_sys_open+0x0/0xd6: ...
<...>-1447  [001] 1038282.286878: sys_openat+0xc/0xe <- do_sys_open: ...

After patching:
<...>-1447  [001] 1038282.286875: myprobe: (do_sys_open+0x0/0xd6) ...
<...>-1447  [001] 1038282.286878: myretprobe: (sys_openat+0xc/0xe <- do_sys_open) ...

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <20090910235345.22412.76527.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-09-11 06:09:47 +02:00
Masami Hiramatsu
eca0d916f6 tracing/kprobes: Add argument name support
Add argument name assignment support and remove "alias" lines from format.
This allows user to assign unique name to each argument. For example,

$ echo p do_sys_open dfd=a0 filename=a1 flags=a2 mode=a3 > kprobe_events

This assigns dfd, filename, flags, and mode to 1st - 4th arguments
respectively. Trace buffer shows those names too.

	<...>-1439  [000] 1200885.933147: do_sys_open+0x0/0xdf: dfd=ffffff9c filename=bfa898ac flags=8000 mode=0

This helps users to know what each value means.

Users can filter each events by these names too. Note that you can not
filter by argN anymore.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <20090910235337.22412.77383.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-09-11 06:08:00 +02:00
Masami Hiramatsu
e08d1c657f tracing/kprobes: Add event profiling support
Add *probe_profile_enable/disable to support kprobes raw events
sampling from perf counters, like other ftrace events, when
CONFIG_PROFILE_EVENT=y.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <20090910235329.22412.94731.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-09-11 05:33:03 +02:00
Masami Hiramatsu
4a846b443b tracing/kprobes: Cleanup kprobe tracer code.
Simplify trace_probe to remove a union, and remove some redundant
wrappers.
And also, cleanup create_trace_probe() function.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <20090910235322.22412.52525.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-09-11 05:31:21 +02:00
Masami Hiramatsu
2fba0c8867 tracing/kprobes: Fix probe offset to be unsigned
Prohibit user to specify negative offset from symbols.
Since kprobe.offset is unsigned int, the offset must be always positive
value.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <20090910235314.22412.64631.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-09-11 04:18:58 +02:00
Masami Hiramatsu
a00e817f42 kprobes/x86-32: Move irq-exit functions to kprobes section
Move irq-exit functions to .kprobes.text section to protect against
kprobes recursion.

When I ran kprobe stress test on x86-32, I found below symbols
cause unrecoverable recursive probing:

	ret_from_exception
	ret_from_intr
	check_userspace
	restore_all
	restore_all_notrace
	restore_nocheck
	irq_return

And also, I found some interrupt/exception entry points that
cause similar problems.

This patch moves those symbols (including their container functions)
to .kprobes.text section to prevent any kprobes probing.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <20090908164755.24050.81182.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-09-11 03:59:35 +02:00
Frederic Weisbecker
8f8ffe2485 Merge commit 'tracing/core' into tracing/kprobes
Conflicts:
	kernel/trace/trace_export.c
	kernel/trace/trace_kprobe.c

Merge reason: This topic branch lacks an important
build fix in tracing/core:

	0dd7b74787:
	tracing: Fix double CPP substitution in TRACE_EVENT_FN

that prevents from multiple tracepoint headers inclusion crashes.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-09-11 01:09:23 +02:00
James Morris
a3c8b97396 Merge branch 'next' into for-linus 2009-09-11 08:04:49 +10:00
Ingo Molnar
e1f8450854 sched: Fix sched::sched_stat_wait tracepoint field
This weird perf trace output:

  cc1-9943  [001]  2802.059479616: sched_stat_wait: task: as:9944 wait: 2801938766276 [ns]

Is caused by setting one component field of the delta to zero
a bit too early. Move it to later.

( Note, this does not affect the NEW_FAIR_SLEEPERS interactivity bug,
  it's just a reporting bug in essence. )

Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Nikos Chantziaras <realnc@arcor.de>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <4AA93D34.8040500@arcor.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-10 20:52:54 +02:00
Ingo Molnar
3f2aa307c4 sched: Disable NEW_FAIR_SLEEPERS for now
Nikos Chantziaras and Jens Axboe reported that turning off
NEW_FAIR_SLEEPERS improves desktop interactivity visibly.

Nikos described his experiences the following way:

  " With this setting, I can do "nice -n 19 make -j20" and
    still have a very smooth desktop and watch a movie at
    the same time.  Various other annoyances (like the
    "logout/shutdown/restart" dialog of KDE not appearing
    at all until the background fade-out effect has finished)
    are also gone.  So this seems to be the single most
    important setting that vastly improves desktop behavior,
    at least here. "

Jens described it the following way, referring to a 10-seconds
xmodmap scheduling delay he was trying to debug:

  " Then I tried switching NO_NEW_FAIR_SLEEPERS on, and then
    I get:

    Performance counter stats for 'xmodmap .xmodmap-carl':

         9.009137  task-clock-msecs         #      0.447 CPUs
               18  context-switches         #      0.002 M/sec
                1  CPU-migrations           #      0.000 M/sec
              315  page-faults              #      0.035 M/sec

    0.020167093  seconds time elapsed

    Woot! "

So disable it for now. In perf trace output i can see weird
delta timestamps:

  cc1-9943  [001]  2802.059479616: sched_stat_wait: task: as:9944 wait: 2801938766276 [ns]

That nsec field is not supposed to be that large. More digging
is needed - but lets turn it off while the real bug is found.

Reported-by: Nikos Chantziaras <realnc@arcor.de>
Tested-by: Nikos Chantziaras <realnc@arcor.de>
Reported-by: Jens Axboe <jens.axboe@oracle.com>
Tested-by: Jens Axboe <jens.axboe@oracle.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <4AA93D34.8040500@arcor.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-10 20:34:48 +02:00
Li Zefan
197e2eabc9 tracing: move PRED macros to trace_events_filter.c
Move DEFINE_COMPARISON_PRED() and DEFINE_EQUALITY_PRED()
  to kernel/trace/trace_events_filter.c

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4AA8579B.4020706@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-09 23:54:11 -04:00
Li Zefan
a5921c6c37 tracing: remove stats from struct tracer
Remove unused field @stats from struct tracer.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4AA8579B.4020706@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-09 23:54:09 -04:00
Li Zefan
bd9cfca9cb tracing: format clean ups
Fix white-space formatting.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4AA8579B.4020706@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-09 23:54:07 -04:00
Li Zefan
e0ab5f2dae tracing: remove dead code
Removes unreachable code.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4AA8579B.4020706@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-09 23:54:06 -04:00
Steven Rostedt
478142c39c tracing: do not grab lock in wakeup latency function tracing
The wakeup tracer, when enabled, has its own function tracer.
It only traces the functions on the CPU where the task it is following
is on. If a task is woken on one CPU but then migrates to another CPU
before it wakes up, the latency tracer will then start tracing functions
on the other CPU.

To find which CPU the task is on, the wakeup function tracer performs
a task_cpu(wakeup_task). But to make sure the task does not disappear
it grabs the wakeup_lock, which is also taken when the task wakes up.
By taking this lock, the function tracer does not need to worry about
the task being freed as it checks its cpu.

Jan Blunck found a problem with this approach on his 32 CPU box. When
a task is being traced by the wakeup tracer, all functions take this
lock. That means that on all 32 CPUs, each function call is taking
this one lock to see if the task is on that CPU. This lock has just
serialized all functions on all 32 CPUs. Needless to say, this caused
major issues on that box. It would even lockup.

This patch changes the wakeup latency to insert a probe on the migrate task
tracepoint. When a task changes its CPU that it will run on, the
probe will take note. Now the wakeup function tracer no longer needs
to take the lock. It only compares the current CPU with a variable that
holds the current CPU the task is on. We don't worry about races since
it is OK to add or miss a function trace.

Reported-by: Jan Blunck <jblunck@suse.de>
Tested-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-09 23:54:04 -04:00
Robert Richter
d8eeb2d3b2 ring-buffer: consolidate interface of rb_buffer_peek()
rb_buffer_peek() operates with struct ring_buffer_per_cpu *cpu_buffer
only. Thus, instead of passing variables buffer and cpu it is better
to use cpu_buffer directly. This also reduces the risk of races since
cpu_buffer is not calculated twice.

Signed-off-by: Robert Richter <robert.richter@amd.com>
LKML-Reference: <1249045084-3028-1-git-send-email-robert.richter@amd.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-09 23:54:02 -04:00
Rafael J. Wysocki
bf992fa2bc Merge branch 'master' into for-linus 2009-09-10 00:02:02 +02:00
Mike Galbraith
61cbe54d94 sched: Keep kthreads at default priority
Removes kthread/workqueue priority boost, they increase worst-case
desktop latencies.

Signed-off-by: Mike Galbraith <efault@gmx.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1252486344.28645.18.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-09 17:30:06 +02:00
Mike Galbraith
172e082a91 sched: Re-tune the scheduler latency defaults to decrease worst-case latencies
Reduce the latency target from 20 msecs to 5 msecs.

Why? Larger latencies increase spread, which is good for scaling,
but bad for worst case latency.

We still have the ilog(nr_cpus) rule to scale up on bigger
server boxes.

Signed-off-by: Mike Galbraith <efault@gmx.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1252486344.28645.18.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-09 17:30:06 +02:00
Mike Galbraith
2bba22c50b sched: Turn off child_runs_first
Set child_runs_first default to off.

It hurts 'optimal' make -j<NR_CPUS> workloads as make jobs
get preempted by child tasks, reducing parallelism.

Note, this patch might make existing races in user
applications more prominent than before - so breakages
might be bisected to this commit.

Child-runs-first is broken on SMP to begin with, and we
already had it off briefly in v2.6.23 so most of the
offenders ought to be fixed. Would be nice not to revert
this commit but fix those apps finally ...

Signed-off-by: Mike Galbraith <efault@gmx.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1252486344.28645.18.camel@marge.simson.net>
[ made the sysctl independent of CONFIG_SCHED_DEBUG, in case
  people want to work around broken apps. ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-09 17:30:05 +02:00
Mike Galbraith
b5d9d734a5 sched: Ensure that a child can't gain time over it's parent after fork()
A fork/exec load is usually "pass the baton", so the child
should never be placed behind the parent.  With START_DEBIT we
make room for the new task, but with child_runs_first, that
room comes out of the _parent's_ hide. There's nothing to say
that the parent wasn't ahead of min_vruntime at fork() time,
which means that the "baton carrier", who is essentially the
parent in drag, can gain time and increase scheduling latencies
for waiters.

With NEW_FAIR_SLEEPERS + START_DEBIT + child_runs_first
enabled, we essentially pass the sleeper fairness off to the
child, which is fine, but if we don't base placement on the
parent's updated vruntime, we can end up compounding latency
woes if the child itself then does fork/exec.  The debit
incurred at fork doesn't hurt the parent who is then going to
sleep and maybe exit, but the child who acquires the error
harms all comers.

This improves latencies of make -j<n> kernel build workloads.

Reported-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-08 13:15:34 +02:00
Peter Zijlstra
71a29aa7b6 sched: Deal with low-load in wake_affine()
wake_affine() would always fail under low-load situations where
both prev and this were idle, because adding a single task will
always be a significant imbalance, even if there's nothing
around that could balance it.

Deal with this by allowing imbalance when there's nothing you
can do about it.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-07 20:39:06 +02:00
Peter Zijlstra
cdd2ab3de4 sched: Remove short cut from select_task_rq_fair()
select_task_rq_fair() incorrectly skips the wake_affine()
logic, remove this.

When prev_cpu == this_cpu, the code jumps straight to the
wake_idle() logic, this doesn't give the wake_affine() logic
the chance to pin the task to this cpu.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-07 20:39:05 +02:00
Jaswinder Singh Rajput
b6d9c25631 Security/SELinux: includecheck fix kernel/sysctl.c
fix the following 'make includecheck' warning:

  kernel/sysctl.c: linux/security.h is included more than once.

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-09-07 11:41:03 +10:00
Ingo Molnar
d28daf923a Merge branch 'tracing/core' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into tracing/core 2009-09-06 06:27:40 +02:00
Ingo Molnar
ed011b22ce Merge commit 'v2.6.31-rc9' into tracing/core
Merge reason: move from -rc5 to -rc9.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-06 06:11:42 +02:00
Linus Torvalds
93697a3cab Merge branch 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf_counter/powerpc: Fix cache event codes for POWER7
  perf_counter: Fix /0 bug in swcounters
  perf_counters: Increase paranoia level
2009-09-05 13:48:37 -07:00
Steven Rostedt
85bac32c4a ring-buffer: only enable ring_buffer_swap_cpu when needed
Since the ability to swap the cpu buffers adds a small overhead to
the recording of a trace, we only want to add it when needed.

Only the irqsoff and preemptoff tracers use this feature, and both are
not recommended for production kernels. This patch disables its use
when neither irqsoff nor preemptoff is configured.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 19:42:22 -04:00
Steven Rostedt
62f0b3eb5c ring-buffer: check for swapped buffers in start of committing
Because the irqsoff tracer can swap an internal CPU buffer, it is possible
that a swap happens between the start of the write and before the committing
bit is set (the committing bit will disable swapping).

This patch adds a check for this and will fail the write if it detects it.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 19:38:42 -04:00
Steven Rostedt
e8165dbb03 tracing: report error in trace if we fail to swap latency buffer
The irqsoff tracer will fail to swap the cpu buffer with the max
buffer if it preempts a commit. Instead of ignoring this, this patch
makes the tracer report it if the last max latency failed due to preempting
a current commit.

The output of the latency tracer will look like this:

 # tracer: irqsoff
 #
 # irqsoff latency trace v1.1.5 on 2.6.31-rc5
 # --------------------------------------------------------------------
 # latency: 112 us, #1/1, CPU#1 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:4)
 #    -----------------
 #    | task: -4281 (uid:0 nice:0 policy:0 rt_prio:0)
 #    -----------------
 #  => started at: save_args
 #  => ended at:   __do_softirq
 #
 #
 #                  _------=> CPU#
 #                 / _-----=> irqs-off
 #                | / _----=> need-resched
 #                || / _---=> hardirq/softirq
 #                ||| / _--=> preempt-depth
 #                |||| /
 #                |||||     delay
 #  cmd     pid   ||||| time  |   caller
 #     \   /      |||||   \   |   /
    bash-4281    1d.s6  265us : update_max_tr_single: Failed to swap buffers due to commit in progress

Note the latency time and the functions that disabled the irqs or preemption
will still be listed.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 19:22:41 -04:00
Steven Rostedt
659372d3e4 tracing: add trace_array_printk for internal tracers to use
This patch adds a trace_array_printk to allow a tracer to use the
trace_printk on its own trace array.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 19:13:53 -04:00
Steven Rostedt
e77405ad80 tracing: pass around ring buffer instead of tracer
The latency tracers (irqsoff and wakeup) can swap trace buffers
on the fly. If an event is happening and has reserved data on one of
the buffers, and the latency tracer swaps the global buffer with the
max buffer, the result is that the event may commit the data to the
wrong buffer.

This patch changes the API to the trace recording to be recieve the
buffer that was used to reserve a commit. Then this buffer can be passed
in to the commit.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 18:59:39 -04:00
Steven Rostedt
f633903af2 tracing: make tracing_reset safe for external use
Reseting the trace buffer without first disabling the buffer and
waiting for any writers to complete, can corrupt the ring buffer.

This patch makes the external version of tracing_reset safe from
corruption by disabling the ring buffer and calling synchronize_sched.

This version can no longer be called from interrupt context. But all those
callers have been removed.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 18:46:51 -04:00
Steven Rostedt
2f26ebd549 tracing: use timestamp to determine start of latency traces
Currently the latency tracers reset the ring buffer. Unfortunately
if a commit is in process (due to a trace event), this can corrupt
the ring buffer. When this happens, the ring buffer will detect
the corruption and then permanently disable the ring buffer.

The bug does not crash the system, but it does prevent further tracing
after the bug is hit.

Instead of reseting the trace buffers, the timestamp of the start of
the trace is used instead. The buffers will still contain the previous
data, but the output will not count any data that is before the
timestamp of the trace.

Note, this only affects the static trace output (trace) and not the
runtime trace output (trace_pipe). The runtime trace output does not
make sense for the latency tracers anyway.

Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 18:44:22 -04:00
Li Zefan
c58b43218c tracing/filters: Defer pred allocation, fix memory leak
The predicates of an event and their filter structure are allocated
when we create an event filter for the first time.

These objects must be created once but each time we come with a new
filter, we overwrite such pre-existing allocation, if any.

Thus, this patch checks if the filter has already been allocated
before going ahead.

Spotted-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
LKML-Reference: <4A9CB1BA.3060402@cn.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-09-04 23:22:33 +02:00
Steven Rostedt
76f0d07376 tracing: remove users of tracing_reset
The function tracing_reset is deprecated for outside use of trace.c.

The new function to reset the the buffers is tracing_reset_online_cpus.

The reason for this is that resetting the buffers while the event
trace points are active can corrupt the buffers, because they may
be writing at the time of reset. The tracing_reset_online_cpus disables
writes and waits for current writers to finish.

This patch replaces all users of tracing_reset except for the latency
tracers. Those changes require more work and will be removed in the
following patches.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 12:12:39 -04:00
Steven Rostedt
621968cdb2 tracing: disable buffers and synchronize_sched before resetting
Resetting the ring buffers while traces are happening can corrupt
the ring buffer and disable it (no kernel crash to worry about).

The safest thing to do is disable the ring buffers, call synchronize_sched()
to wait for all current writers to finish and then reset the buffer.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 12:02:35 -04:00
Steven Rostedt
b8de7bd168 tracing: disable update max tracer while reading trace
When reading the tracer from the trace file, updating the max latency
may corrupt the output. This patch disables the tracing of the max
latency while reading the trace file.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 11:52:24 -04:00
Steven Rostedt
8248ac052d tracing: print out start and stop in latency traces
During development of the tracer, we would copy information from
the live tracer to the max tracer with one memcpy. Since then we
added a generic ring buffer and we handle the copies differently now.
Unfortunately, we never copied the critical section information, and
we lost the output:

 #  => started at: kmem_cache_alloc
 #  => ended at:   kmem_cache_alloc

This patch adds back the critical start and end copying as well as
removes the unused "trace_idx" and "overrun" fields of the
trace_array_cpu structure.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 11:48:12 -04:00
Steven Rostedt
077c5407cd ring-buffer: disable all cpu buffers when one finds a problem
Currently the way RB_WARN_ON works, is to disable either the current
CPU buffer or all CPU buffers, depending on whether a ring_buffer or
ring_buffer_per_cpu struct was passed into the macro.

Most users of the RB_WARN_ON pass in the CPU buffer, so only the one
CPU buffer gets disabled but the rest are still active. This may
confuse users even though a warning is sent to the console.

This patch changes the macro to disable the entire buffer even if
the CPU buffer is passed in.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 11:46:25 -04:00
Steven Rostedt
a1863c212b ring-buffer: do not count discarded events
The latency tracers report the number of items in the trace buffer.
This uses the ring buffer data to calculate this. Because discarded
events are also counted, the numbers do not match the number of items
that are printed. The ring buffer also adds a "padding" item to the
end of each buffer page which also gets counted as a discarded item.

This patch decrements the counter to the page entries on a discard.
This allows us to ignore discarded entries while reading the buffer.

Decrementing the counter is still safe since it can only happen while
the committing flag is still set.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 11:43:36 -04:00
Steven Rostedt
dc892f7339 ring-buffer: remove ring_buffer_event_discard
The function ring_buffer_event_discard can be used on any item in the
ring buffer, even after the item was committed. This function provides
no safety nets and is very race prone.

An item may be safely removed from the ring buffer before it is committed
with the ring_buffer_discard_commit.

Since there are currently no users of this function, and because this
function is racey and error prone, this patch removes it altogether.

Note, removing this function also allows the counters to ignore
all discarded events (patches will follow).

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 11:36:19 -04:00
Steven Rostedt
7e9391cfed ring-buffer: fix ring_buffer_read crossing pages
When the ring buffer uses an iterator (static read mode, not on the
fly reading), when it crosses a page boundery, it will skip the first
entry on the next page. The reason is that the last entry of a page
is usually padding if the page is not full. The padding will not be
returned to the user.

The problem arises on ring_buffer_read because it also increments the
iterator. Because both the read and peek use the same rb_iter_peek,
the rb_iter_peak will return the padding but also increment to the next
item. This is because the ring_buffer_peek will not incerment it
itself.

The ring_buffer_read will increment it again and then call rb_iter_peek
again to get the next item. But that will be the second item, not the
first one on the page.

The reason this never showed up before, is because the ftrace utility
always calls ring_buffer_peek first and only uses ring_buffer_read
to increment to the next item. The ring_buffer_peek will always keep
the pointer to a valid item and not padding. This just hid the bug.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 11:28:39 -04:00
Steven Rostedt
1b959e18c4 ring-buffer: remove unnecessary cpu_relax
The loops in the ring buffer that use cpu_relax are not dependent on
other CPUs. They simply came across some padding in the ring buffer and
are skipping over them. It is a normal loop and does not require a
cpu_relax.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 11:25:27 -04:00
Steven Rostedt
98277991a9 ring-buffer: do not swap buffers during a commit
If a commit is taking place on a CPU ring buffer, do not allow it to
be swapped. Return -EBUSY when this is detected instead.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 11:22:47 -04:00
Steven Rostedt
41b6a95d69 ring-buffer: do not reset while in a commit
The callers of reset must ensure that no commit can be taking place
at the time of the reset. If it does then we may corrupt the ring buffer.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 11:15:08 -04:00
Ingo Molnar
d7ea17a769 sched: Fix dynamic power-balancing crash
This crash:

[ 1774.088275] divide error: 0000 [#1] SMP
[ 1774.100355] CPU 13
[ 1774.102498] Modules linked in:
[ 1774.105631] Pid: 30881, comm: hackbench Not tainted 2.6.31-rc8-tip-01308-g484d664-dirty #1629 X8DTN
[ 1774.114807] RIP: 0010:[<ffffffff81041c38>]  [<ffffffff81041c38>]
sched_balance_self+0x19b/0x2d4

Triggers because update_group_power() modifies the sd tree and does
temporary calculations there - not considering that other CPUs
could observe intermediate values, such as the zero initial value.

Calculate it in a temporary variable instead. (we need no memory
barrier as these are all statistical values anyway)

Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20090904092742.GA11014@elte.hu>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-04 11:52:52 +02:00
Peter Zijlstra
18a3885fc1 sched: Remove reciprocal for cpu_power
Its a source of fail, also, now that cpu_power is dynamical,
its a waste of time.

before:
<idle>-0   [000]   132.877936: find_busiest_group: avg_load: 0 group_load: 8241 power: 1

after:
bash-1689  [001]   137.862151: find_busiest_group: avg_load: 10636288 group_load: 10387 power: 1

[ v2: build fix from From: Andreas Herrmann ]

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Gautham R Shenoy <ego@in.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
LKML-Reference: <20090901083826.425896304@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-04 10:09:56 +02:00
Gautham R Shenoy
d899a789c2 sched: Try to deal with low capacity, fix update_sd_power_savings_stats()
sgs.group_capacity can now be 0, if for some reason
group->__cpu_power happens to be less than SCHED_LOAD_SCALE/2.

In that case, we need the following fix to make it work for
update_sd_power_savings_stats(). That's because both
sum_nr_running and group_capacity are unsigned longs.

Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-04 10:09:56 +02:00
Peter Zijlstra
bdb94aa5db sched: Try to deal with low capacity
When the capacity drops low, we want to migrate load away.
Allow the load-balancer to remove all tasks when we hit rock
bottom.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Gautham R Shenoy <ego@in.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
LKML-Reference: <20090901083826.342231003@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-04 10:09:55 +02:00
Peter Zijlstra
e9e9250bc7 sched: Scale down cpu_power due to RT tasks
Keep an average on the amount of time spend on RT tasks and use
that fraction to scale down the cpu_power for regular tasks.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Gautham R Shenoy <ego@in.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
LKML-Reference: <20090901083826.287778431@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-04 10:09:55 +02:00
Peter Zijlstra
ab29230e67 sched: Implement dynamic cpu_power
Recompute the cpu_power for each cpu during load-balance.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Gautham R Shenoy <ego@in.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
LKML-Reference: <20090901083826.162033479@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-04 10:09:54 +02:00
Peter Zijlstra
a52bfd7358 sched: Add smt_gain
The idea is that multi-threading a core yields more work
capacity than a single thread, provide a way to express a
static gain for threads.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Gautham R Shenoy <ego@in.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
LKML-Reference: <20090901083826.073345955@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-04 10:09:54 +02:00
Peter Zijlstra
cc9fba7d76 sched: Update the cpu_power sum during load-balance
In order to prepare for a more dynamic cpu_power, update the
group sum while walking the sched domains during load-balance.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Gautham R Shenoy <ego@in.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
LKML-Reference: <20090901083825.985050292@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-04 10:09:53 +02:00
Peter Zijlstra
b5d978e0c7 sched: Add SD_PREFER_SIBLING
Do the placement thing using SD flags.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Gautham R Shenoy <ego@in.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
LKML-Reference: <20090901083825.897028974@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-04 10:09:53 +02:00
Peter Zijlstra
f93e65c186 sched: Restore __cpu_power to a straight sum of power
cpu_power is supposed to be a representation of the process
capacity of the cpu, not a value to randomly tweak in order to
affect placement.

Remove the placement hacks.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Gautham R Shenoy <ego@in.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
LKML-Reference: <20090901083825.810860576@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-04 10:09:53 +02:00
Ingo Molnar
9aa55fbd01 Merge branches 'sched/domains' and 'sched/clock' into sched/core
Merge reason: both topics are ready now, and we want to merge dependent
              changes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-04 10:08:47 +02:00
Ingo Molnar
29e2035bdd Merge branch 'linus' into core/rcu
Merge reason: Avoid fuzz in init/main.c and update from rc6 to rc8.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-04 09:29:05 +02:00
Ingo Molnar
dc86cabe4b perf_counter: Fix output-sharing error path
We forget to release the fd in the PERF_FLAG_FD_OUTPUT
error path.

Reorganize the error flow here to be a clean fall-through
logic.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-03 18:46:23 +02:00
Ingo Molnar
0fbdea19e9 perf_counter: Introduce new (non-)paranoia level to allow raw tracepoint access
I want to sample inherited tracepoint workloads as a normal
user and the CAP_SYS_ADMIN check prevents me from doing that
right now.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-02 21:53:02 +02:00
Ingo Molnar
f76bd108e5 Merge branch 'perfcounters/urgent' into perfcounters/core
Merge reason: We are going to modify a place modified by
              perfcounters/urgent.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-02 21:42:59 +02:00
David Howells
ee18d64c1f KEYS: Add a keyctl to install a process's session keyring on its parent [try #6]
Add a keyctl to install a process's session keyring onto its parent.  This
replaces the parent's session keyring.  Because the COW credential code does
not permit one process to change another process's credentials directly, the
change is deferred until userspace next starts executing again.  Normally this
will be after a wait*() syscall.

To support this, three new security hooks have been provided:
cred_alloc_blank() to allocate unset security creds, cred_transfer() to fill in
the blank security creds and key_session_to_parent() - which asks the LSM if
the process may replace its parent's session keyring.

The replacement may only happen if the process has the same ownership details
as its parent, and the process has LINK permission on the session keyring, and
the session keyring is owned by the process, and the LSM permits it.

Note that this requires alteration to each architecture's notify_resume path.
This has been done for all arches barring blackfin, m68k* and xtensa, all of
which need assembly alteration to support TIF_NOTIFY_RESUME.  This allows the
replacement to be performed at the point the parent process resumes userspace
execution.

This allows the userspace AFS pioctl emulation to fully emulate newpag() and
the VIOCSETTOK and VIOCSETTOK2 pioctls, all of which require the ability to
alter the parent process's PAG membership.  However, since kAFS doesn't use
PAGs per se, but rather dumps the keys into the session keyring, the session
keyring of the parent must be replaced if, for example, VIOCSETTOK is passed
the newpag flag.

This can be tested with the following program:

	#include <stdio.h>
	#include <stdlib.h>
	#include <keyutils.h>

	#define KEYCTL_SESSION_TO_PARENT	18

	#define OSERROR(X, S) do { if ((long)(X) == -1) { perror(S); exit(1); } } while(0)

	int main(int argc, char **argv)
	{
		key_serial_t keyring, key;
		long ret;

		keyring = keyctl_join_session_keyring(argv[1]);
		OSERROR(keyring, "keyctl_join_session_keyring");

		key = add_key("user", "a", "b", 1, keyring);
		OSERROR(key, "add_key");

		ret = keyctl(KEYCTL_SESSION_TO_PARENT);
		OSERROR(ret, "KEYCTL_SESSION_TO_PARENT");

		return 0;
	}

Compiled and linked with -lkeyutils, you should see something like:

	[dhowells@andromeda ~]$ keyctl show
	Session Keyring
	       -3 --alswrv   4043  4043  keyring: _ses
	355907932 --alswrv   4043    -1   \_ keyring: _uid.4043
	[dhowells@andromeda ~]$ /tmp/newpag
	[dhowells@andromeda ~]$ keyctl show
	Session Keyring
	       -3 --alswrv   4043  4043  keyring: _ses
	1055658746 --alswrv   4043  4043   \_ user: a
	[dhowells@andromeda ~]$ /tmp/newpag hello
	[dhowells@andromeda ~]$ keyctl show
	Session Keyring
	       -3 --alswrv   4043  4043  keyring: hello
	340417692 --alswrv   4043  4043   \_ user: a

Where the test program creates a new session keyring, sticks a user key named
'a' into it and then installs it on its parent.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-09-02 21:29:22 +10:00
David Howells
e0e817392b CRED: Add some configurable debugging [try #6]
Add a config option (CONFIG_DEBUG_CREDENTIALS) to turn on some debug checking
for credential management.  The additional code keeps track of the number of
pointers from task_structs to any given cred struct, and checks to see that
this number never exceeds the usage count of the cred struct (which includes
all references, not just those from task_structs).

Furthermore, if SELinux is enabled, the code also checks that the security
pointer in the cred struct is never seen to be invalid.

This attempts to catch the bug whereby inode_has_perm() faults in an nfsd
kernel thread on seeing cred->security be a NULL pointer (it appears that the
credential struct has been previously released):

	http://www.kerneloops.org/oops.php?number=252883

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-09-02 21:29:01 +10:00
Peter Zijlstra
768d0c2722 sched: Add wait, sleep and iowait accounting tracepoints
Add 3 schedstat tracepoints to help account for wait-time,
sleep-time and iowait-time.

They can also be used as a perf-counter source to profile tasks
on these clocks.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
LKML-Reference: <new-submission>
[ build fix for the !CONFIG_SCHEDSTATS case ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-02 09:12:18 +02:00
Arjan van de Ven
8f0dfc34e9 sched: Provide iowait counters
For counting how long an application has been waiting for
(disk) IO, there currently is only the HZ sample driven
information available, while for all other counters in this
class, a high resolution version is available via
CONFIG_SCHEDSTATS.

In order to make an improved bootchart tool possible, we also
need a higher resolution version of the iowait time.

This patch below adds this scheduler statistic to the kernel.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <4A64B813.1080506@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-02 08:44:08 +02:00
Ingo Molnar
f14eff1cc2 Merge commit 'v2.6.31-rc8' into sched/core
Merge reason: bump from rc5 to rc8, but also pick up TP_perf_assign()
              API, a patch will be queued that depends on it.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-02 08:20:35 +02:00
Ingo Molnar
936e894a97 Merge commit 'v2.6.31-rc8' into x86/txt
Conflicts:
	arch/x86/kernel/reboot.c
	security/Kconfig

Merge reason: resolve the conflicts, bump up from rc3 to rc8.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-02 08:17:56 +02:00
Shane Wang
69575d3886 x86, intel_txt: clean up the impact on generic code, unbreak non-x86
Move tboot.h from asm to linux to fix the build errors of intel_txt
patch on non-X86 platforms. Remove the tboot code from generic code
init/main.c and kernel/cpu.c.

Signed-off-by: Shane Wang <shane.wang@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-09-01 18:25:07 -07:00
Heiko Carstens
892a7c67c1 locking: Allow arch-inlined spinlocks
This allows an architecture to specify per lock variant if the
locking code should be kept out-of-line or inlined.

If an architecure wants out-of-line locking code no change is
needed. To force inlining of e.g. spin_lock() the line:

  #define __always_inline__spin_lock

needs to be added to arch/<...>/include/asm/spinlock.h

If CONFIG_DEBUG_SPINLOCK or CONFIG_GENERIC_LOCKBREAK are
defined the per architecture defines are (partly) ignored and
still out-of-line spinlock code will be generated.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Horst Hartmann <horsth@linux.vnet.ibm.com>
Cc: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: David Miller <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: <linux-arch@vger.kernel.org>
LKML-Reference: <20090831124418.375299024@de.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-31 18:08:50 +02:00
Heiko Carstens
69d0ee7377 locking: Move spinlock function bodies to header file
Move spinlock function bodies to header file by creating a
static inline version of each variant. Use the inline version
on the out-of-line code.

This shouldn't make any difference besides that the spinlock
code can now be used to generate inlined spinlock code.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Horst Hartmann <horsth@linux.vnet.ibm.com>
Cc: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: David Miller <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: <linux-arch@vger.kernel.org>
LKML-Reference: <20090831124417.859022429@de.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-31 18:08:50 +02:00
Ingo Molnar
bbe69aa57a Merge commit 'v2.6.31-rc8' into core/locking
Merge reason: we were on -rc4, move to -rc8 before applying
              a new batch of locking infrastructure changes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-31 18:05:25 +02:00
Li Zefan
8e254c1d18 tracing/filters: Defer pred allocation
init_preds() allocates about 5392 bytes of memory (on x86_32) for
a TRACE_EVENT. With my config, at system boot total memory occupied
is:

	5392 * (642 + 15) == 3459KB

642 == cat available_events | wc -l
15 == number of dirs in events/ftrace

That's quite a lot, so we'd better defer memory allocation util
it's needed, that's when filter is used.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
LKML-Reference: <4A9B8EA5.6020700@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-31 10:58:08 +02:00
Masami Hiramatsu
65e234ec2c kprobes: Prohibit to probe native_get_debugreg
Since do_debug() calls get_debugreg(), native_get_debugreg() will be
called from singlestepping. This can cause an int3 infinite loop.

We can't put it in the .text.kprobes section because it is inlined,
then we blacklist its name.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <20090827172332.8246.34194.stgit@localhost.localdomain>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-30 03:15:55 +02:00
Masami Hiramatsu
8f27008358 kprobes: Fix to add __kprobes to notify_die
Add __kprobes to notify_die() because do_int3() calls notify_die()
instead of atomic_notify_call_chain() which is already marked as
__kprobes.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <20090827172318.8246.53702.stgit@localhost.localdomain>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-30 03:08:26 +02:00
Yinghai Lu
372e24b0cb irq: Make sure irq_desc for legacy irq get correct node setting
when there is no ram on node 0.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
LKML-Reference: <4A95C32D.5040605@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-29 15:53:00 +02:00
Anirban Sinha
84e9dabf6e sched: Rename init_cfs_rq => init_tg_cfs_rq
... so that it does not share a common name with a function
within the same scope.

Signed-off-by: Anirban Sinha <asinha@zeugmasystems.com>
LKML-Reference: <DDFD17CC94A9BD49A82147DDF7D545C501EA98A6@exchange.ZeugmaSystems.local>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-29 15:51:16 +02:00
Paul E. McKenney
868489660d rcu: Changes from reviews: avoid casts, fix/add warnings, improve comments
Changes suggested by review comments from Josh Triplett and
Mathieu Desnoyers.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <20090827220012.GA30525@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-29 15:34:40 +02:00
Paul E. McKenney
dd5d19bafd rcu: Create rcutree plugins to handle hotplug CPU for multi-level trees
When offlining CPUs from a multi-level tree, there is the
possibility of offlining the last CPU from a given node when
there are preempted RCU read-side critical sections that
started life on one of the CPUs on that node.

In this case, the corresponding tasks will be enqueued via the
task_struct's rcu_node_entry list_head onto one of the
rcu_node's blocked_tasks[] lists.  These tasks need to be moved
somewhere else so that they will prevent the current grace
period from ending. That somewhere is the root rcu_node.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <20090827215816.GA30472@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-29 15:34:39 +02:00
Xiao Guangrong
3f0a525ebf itimers: Add tracepoints for itimer
Add tracepoints for all itimer variants: ITIMER_REAL, ITIMER_VIRTUAL
and ITIMER_PROF.

[ tglx: Fixed comments and made the output more readable, parseable
  	and consistent. Replaced pid_vnr by pid_nr because the hrtimer
  	callback can happen in any namespace ]

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Anton Blanchard <anton@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Zhaolei <zhaolei@cn.fujitsu.com>
LKML-Reference: <4A7F8B6E.2010109@cn.fujitsu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-29 14:10:07 +02:00
Xiao Guangrong
c6a2a17702 hrtimer: Add tracepoint for hrtimers
Add tracepoints which cover the life cycle of a hrtimer. The
tracepoints are integrated with the already existing debug_object
debug points as far as possible.

[ tglx: Fixed comments, made output conistent, easier to read and
  	parse. Fixed output for 32bit archs which do not use the
  	scalar representation of ktime_t. Hand current time to
  	trace_hrtimer_expiry_entry instead of calling get_time()
  	inside of the trace assignment. ]

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Anton Blanchard <anton@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Zhaolei <zhaolei@cn.fujitsu.com>
LKML-Reference: <4A7F8B2B.5020908@cn.fujitsu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-29 14:10:06 +02:00
Xiao Guangrong
2b022e3d4b timers: Add tracepoints for timer_list timers
Add tracepoints which cover the timer life cycle. The tracepoints are
integrated with the already existing debug_object debug points as far
as possible.

Based on patches from 
Mathieu: http://marc.info/?l=linux-kernel&m=123791201816247&w=2
and 
Anton: http://marc.info/?l=linux-kernel&m=124331396919301&w=2

[ tglx: Fixed timeout value in timer_start tracepoint, massaged
  comments and made the printk's more readable ]

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Zhaolei <zhaolei@cn.fujitsu.com>
LKML-Reference: <4A7F8A9B.3040201@cn.fujitsu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-29 14:10:06 +02:00
Ming Lei
a417887637 lockdep: Remove recursion stattistics
Since lockdep has introduced BFS to avoid recursion, statistics
for recursion does not make any sense now. So remove them.

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Cc: a.p.zijlstra@chello.nl
LKML-Reference: <1251542879-5211-1-git-send-email-tom.leiming@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-29 13:22:36 +02:00
Peter Zijlstra
eced1dfcfc perf_counter: Fix /0 bug in swcounters
We have a race in the swcounter stuff where we can start
counting a counter that has never been enabled, this leads to a
/0 situation.

The below avoids the /0 but doesn't close the race, this would
need a new counter state.

The race is due to perf_swcounter_is_counting() which cannot
discern between disabled due to scheduled out, and disabled for
any other reason.

Such a crash has been seen by Ingo:

[  967.092372] divide error: 0000 [#1] SMP
[  967.096499] last sysfs file: /sys/devices/system/cpu/cpu15/cache/index2/shared_cpu_map
[  967.104846] CPU 5
[  967.106965] Modules linked in:
[  967.110169] Pid: 3351, comm: hackbench Not tainted 2.6.31-rc8-tip-01158-gd940a54-dirty #1568 X8DTN
[  967.119456] RIP: 0010:[<ffffffff810c0aba>]  [<ffffffff810c0aba>] perf_swcounter_ctx_event+0x127/0x1af
[  967.129137] RSP: 0018:ffff8801a95abd70  EFLAGS: 00010046
[  967.134699] RAX: 0000000000000002 RBX: ffff8801bd645c00 RCX: 0000000000000002
[  967.142162] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8801bd645d40
[  967.149584] RBP: ffff8801a95abdb0 R08: 0000000000000001 R09: ffff8801a95abe00
[  967.157042] R10: 0000000000000037 R11: ffff8801aa1245f8 R12: ffff8801a95abe00
[  967.164481] R13: ffff8801a95abe00 R14: ffff8801aa1c0e78 R15: 0000000000000001
[  967.171953] FS:  0000000000000000(0000) GS:ffffc90000a00000(0063) knlGS:00000000f7f486c0
[  967.180406] CS:  0010 DS: 002b ES: 002b CR0: 000000008005003b
[  967.186374] CR2: 000000004822c0ac CR3: 00000001b19a2000 CR4: 00000000000006e0
[  967.193770] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  967.201224] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[  967.208692] Process hackbench (pid: 3351, threadinfo ffff8801a95aa000, task ffff8801a96b0000)
[  967.217607] Stack:
[  967.219711]  0000000000000000 0000000000000037 0000000200000001 ffffc90000a1107c
[  967.227296] <0> ffff8801a95abe00 0000000000000001 0000000000000001 0000000000000037
[  967.235333] <0> ffff8801a95abdf0 ffffffff810c0c20 0000000200a14f30 ffff8801a95abe40
[  967.243532] Call Trace:
[  967.246103]  [<ffffffff810c0c20>] do_perf_swcounter_event+0xde/0xec
[  967.252635]  [<ffffffff810c0ca7>] perf_tpcounter_event+0x79/0x7b
[  967.258957]  [<ffffffff81037f73>] ftrace_profile_sched_switch+0xc0/0xcb
[  967.265791]  [<ffffffff8155f22d>] schedule+0x429/0x4c4
[  967.271156]  [<ffffffff8100c01e>] int_careful+0xd/0x14

Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1251472247.17617.74.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-29 13:20:11 +02:00
Ingo Molnar
73222acf96 Merge branch 'tip/tracing/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into tracing/core 2009-08-29 13:06:05 +02:00
Thomas Gleixner
f71bb0ac5e Merge branch 'timers/posixtimers' into timers/tracing
Merge reason: timer tracepoint patches depend on both branches

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-29 10:34:29 +02:00
Stephen Hemminger
2bc481cf43 pktgen: spin using hrtimer
This changes how the pktgen thread spins/waits between
packets if delay is configured. It uses a high res timer to
wait for time to arrive.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-28 23:41:29 -07:00
Ingo Molnar
ea6bff3685 modules: Fix build error in the !CONFIG_KALLSYMS case
> James Bottomley (1):
>       module: workaround duplicate section names

-tip testing found that this patch breaks the build on x86 if
CONFIG_KALLSYMS is disabled:

 kernel/module.c: In function ‘load_module’:
 kernel/module.c:2367: error: ‘struct module’ has no member named ‘sect_attrs’
 distcc[8269] ERROR: compile kernel/module.c on ph/32 failed
 make[1]: *** [kernel/module.o] Error 1
 make: *** [kernel] Error 2
 make: *** Waiting for unfinished jobs....

Commit 1b364bf misses the fact that section attributes are only
built and dealt with if kallsyms is enabled. The patch below fixes
this.

( note, technically speaking this should depend on CONFIG_SYSFS as
  well but this patch is correct too and keeps the #ifdef less
  intrusive - in the KALLSYMS && !SYSFS case the code is a NOP. )

Signed-off-by: Ingo Molnar <mingo@elte.hu>
[ Replaced patch with a slightly cleaner variation by James Bottomley ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-28 19:35:00 -10:00
Thomas Gleixner
7285dd7fd3 clocksource: Resolve cpu hotplug dead lock with TSC unstable
Martin Schwidefsky analyzed it:
To register a clocksource the clocksource_mutex is acquired and if
necessary timekeeping_notify is called to install the clocksource as
the timekeeper clock. timekeeping_notify uses stop_machine which needs
to take cpu_add_remove_lock mutex.
Starting a new cpu is done with the cpu_add_remove_lock mutex held.
native_cpu_up checks the tsc of the new cpu and if the tsc is no good
clocksource_change_rating is called. Which needs the clocksource_mutex
and the deadlock is complete.

The solution is to replace the TSC via the clocksource watchdog
mechanism. Mark the TSC as unstable and schedule the watchdog work so
it gets removed in the watchdog thread context.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <new-submission>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: John Stultz <johnstul@us.ibm.com>
2009-08-28 20:25:24 +02:00
Ingo Molnar
6bb56347f5 perf_counters: Increase paranoia level
Per-cpu counters are an ASLR information leak as they show
the execution other tasks do. Increase the paranoia level
to 1, which disallows per-cpu counters. (they still allow
counting/profiling of own tasks - and admin can profile
everything.)

Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-28 13:44:53 +02:00
Peter Zijlstra
34d76c4155 sched: Fix division by zero - really
When re-computing the shares for each task group's cpu
representation we need the ratio of weight on each cpu vs the
total weight of the sched domain.

Since load-balancing is loosely (read not) synchronized, the
weight of individual cpus can change between doing the sum and
calculating the ratio.

The previous patch dealt with only one of the race scenarios,
this patch side steps them all by saving a snapshot of all the
individual cpu weights, thereby always working on a consistent
set.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: torvalds@linux-foundation.org
Cc: jes@sgi.com
Cc: jens.axboe@oracle.com
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1251371336.18584.77.camel@twins>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-28 08:26:49 +02:00
Steven Rostedt
5d4a9dba2d tracing: only show tracing_max_latency when latency tracer configured
The tracing_max_latency file should only be present when one of the
latency tracers ({preempt|irqs}off, wakeup*) are enabled.

This patch also removes tracing_thresh when latency tracers are not
enabled, as well as compiles out code that is only used for latency
tracers.

Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-08-27 16:58:05 -04:00
Steven Rostedt
c0729be99c tracing: remove legacy select of MARKERS by context switch tracing
The context switch tracer was made before tracepoints were mature, and
the original version used markers. This is no longer true and this
patch removes the select.

Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-08-27 16:58:03 -04:00
James Bottomley
1b364bf438 module: workaround duplicate section names
The root cause is a duplicate section name (.text); is this legal?
[ Amerigo Wang: "AFAIK, yes." ]

However, there's a problem with commit
6d76013381 in that if you fail to allocate
a mod->sect_attrs (in this case it's null because of the duplication),
it still gets used without checking in add_notes_attrs()

This should fix it

[ This patch leaves other problems, particularly the sections directory,
  but recent parisc toolchains seem to produce these modules and this
  prevents a crash and is a minimal change -- RR ]

Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Tested-by: Helge Deller <deller@gmx.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-27 12:33:19 -07:00
Rusty Russell
7d1d16e416 module: fix BUG_ON() for powerpc (and other function descriptor archs)
The rarely-used symbol_put_addr() needs to use dereference_function_descriptor
on powerpc.

Reported-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-27 12:33:19 -07:00
Thomas Gleixner
4dbc9ca219 genirq: Do not mask oneshot edge type interrupts
Masking oneshot edge type interrupts is wrong as we might lose an
interrupt which is issued when the threaded handler is handling the
device. We can keep the irq unmasked safely as with edge type
interrupts there is no danger of interrupt floods. If the threaded
handler has not yet finished then IRQTF_RUNTHREAD is set which will
keep the handler thread active.

Debugged and verified in preempt-rt.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-27 09:38:49 +02:00
Frederic Weisbecker
f8468f3695 tracing: Remove unneeded pointer casts
Cleaup uneeded casts from void * to char * in syscalls tracing file.

Reported-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com
Cc: Steven Rostedt <rostedt@goodmis.org>
2009-08-27 05:23:29 +02:00
Benjamin Herrenschmidt
f480fe3916 Merge commit 'origin/master' into next 2009-08-27 13:12:40 +10:00
Frederic Weisbecker
aeaeae1187 tracing: Restore the const qualifier for field names and types definition
Restore the const qualifier in field's name and type parameters of
trace_define_field that was lost while solving a conflict.

Fields names and types are defined as builtin constant strings in
static TRACE_EVENTs. But kprobes allocates these dynamically.

That said, we still want to always pass these strings as const char *
in trace_define_fields() to avoid any further accidental writes on
the pointed strings.

Reported-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
2009-08-27 05:09:51 +02:00
Oleg Nesterov
4ab6c08336 clone(): fix race between copy_process() and de_thread()
Spotted by Hiroshi Shimamoto who also provided the test-case below.

copy_process() uses signal->count as a reference counter, but it is not.
This test case

	#include <sys/types.h>
	#include <sys/wait.h>
	#include <unistd.h>
	#include <stdio.h>
	#include <errno.h>
	#include <pthread.h>

	void *null_thread(void *p)
	{
		for (;;)
			sleep(1);

		return NULL;
	}

	void *exec_thread(void *p)
	{
		execl("/bin/true", "/bin/true", NULL);

		return null_thread(p);
	}

	int main(int argc, char **argv)
	{
		for (;;) {
			pid_t pid;
			int ret, status;

			pid = fork();
			if (pid < 0)
				break;

			if (!pid) {
				pthread_t tid;

				pthread_create(&tid, NULL, exec_thread, NULL);
				for (;;)
					pthread_create(&tid, NULL, null_thread, NULL);
			}

			do {
				ret = waitpid(pid, &status, 0);
			} while (ret == -1 && errno == EINTR);
		}

		return 0;
	}

quickly creates an unkillable task.

If copy_process(CLONE_THREAD) races with de_thread()
copy_signal()->atomic(signal->count) breaks the signal->notify_count
logic, and the execing thread can hang forever in kernel space.

Change copy_process() to increment count/live only when we know for sure
we can't fail.  In this case the forked thread will take care of its
reference to signal correctly.

If copy_process() fails, check CLONE_THREAD flag.  If it it set - do
nothing, the counters were not changed and current belongs to the same
thread group.  If it is not set, ->signal must be released in any case
(and ->count must be == 1), the forked child is the only thread in the
thread group.

We need more cleanups here, in particular signal->count should not be used
by de_thread/__exit_signal at all.  This patch only fixes the bug.

Reported-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Tested-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-26 20:06:52 -07:00
Frederic Weisbecker
24851d2447 tracing/kprobes: Dump the culprit kprobe in case of kprobe recursion
Kprobes can enter into a probing recursion, ie: a kprobe that does an
endless loop because one of its core mechanism function used during
probing is also probed itself.

This patch helps pinpointing the kprobe that raised such recursion
by dumping it and raising a BUG instead of a warning (we also disarm
the kprobe to try avoiding recursion in BUG itself). Having a BUG
instead of a warning stops the stacktrace in the right place and
doesn't pollute the logs with hundreds of traces that eventually end
up in a stack overflow.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
2009-08-27 02:33:03 +02:00
Masami Hiramatsu
30a7e073b5 tracing/kprobes: Change trace_arg to probe_arg
Change trace_arg_string() and parse_trace_arg() to probe_arg_string()
and parse_probe_arg(), since those are kprobe-tracer local functions.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it>
Cc: Roland McGrath <roland@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
LKML-Reference: <20090821194351.12478.15247.stgit@localhost.localdomain>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-27 02:32:59 +02:00
Masami Hiramatsu
38a47497d9 tracing/kprobes: Fix format typo in trace_kprobes
Fix a format typo in kprobe-tracer.

Currently, it shows 'tsize' in format;

$ cat /debug/tracing/events/kprobes/event/format
...
        field: unsigned long ip;        offset:16;tsize:8;
        field: int nargs;       offset:24;tsize:4;
...

This should be '\tsize';

$ cat /debug/tracing/events/kprobes/event/format
...
        field: unsigned long ip;        offset:16;	size:8;
        field: int nargs;       offset:24;	size:4;
...

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it>
Cc: Roland McGrath <roland@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
LKML-Reference: <20090821194343.12478.37618.stgit@localhost.localdomain>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-27 02:32:54 +02:00
Masami Hiramatsu
cd7e7bd5e4 tracing: Add kprobes event profiling interface
Add profiling interfaces for each kprobes event. This interface provides
how many times each probe hit or missed.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it>
Cc: Roland McGrath <roland@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
LKML-Reference: <20090813203541.31965.8452.stgit@localhost.localdomain>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-27 02:32:39 +02:00
Masami Hiramatsu
ff50d99136 tracing: Kprobe tracer assigns new event ids for each event
Assign new event ids for each kprobes event. This doesn't clear
ring_buffer when unregistering each kprobe event. Thus, if you mind
'Unknown event' messages, clear the buffer manually after changing
kprobe events.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it>
Cc: Roland McGrath <roland@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
LKML-Reference: <20090813203534.31965.49105.stgit@localhost.localdomain>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-27 02:32:33 +02:00
Masami Hiramatsu
4263565d49 tracing: Generate names for each kprobe event automatically
Generate names for each kprobe event based on the probe point.
(SYMBOL+offs or MEMADDR).

Also remove generic k*probe event types because there is no user
of those types.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it>
Cc: Roland McGrath <roland@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
LKML-Reference: <20090813203526.31965.56672.stgit@localhost.localdomain>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-27 02:32:28 +02:00
Masami Hiramatsu
a82378d880 tracing: Kprobe-tracer supports more than 6 arguments
Support up to 128 arguments to fetch for each kprobes event.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it>
Cc: Roland McGrath <roland@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
LKML-Reference: <20090813203518.31965.96979.stgit@localhost.localdomain>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-27 02:32:23 +02:00
Masami Hiramatsu
413d37d1eb tracing: Add kprobe-based event tracer
Add kprobes-based event tracer on ftrace.

This tracer is similar to the events tracer which is based on Tracepoint
infrastructure. Instead of Tracepoint, this tracer is based on kprobes
(kprobe and kretprobe). It probes anywhere where kprobes can probe(this
 means, all functions body except for __kprobes functions).

Similar to the events tracer, this tracer doesn't need to be activated
via current_tracer, instead of that, just set probe points via
/sys/kernel/debug/tracing/kprobe_events. And you can set filters on each
probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter.

This tracer supports following probe arguments for each probe.

  %REG  : Fetch register REG
  sN    : Fetch Nth entry of stack (N >= 0)
  sa    : Fetch stack address.
  @ADDR : Fetch memory at ADDR (ADDR should be in kernel)
  @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol)
  aN    : Fetch function argument. (N >= 0)
  rv    : Fetch return value.
  ra    : Fetch return address.
  +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address.

See Documentation/trace/kprobetrace.txt in the next patch for details.

Changes from v13:
 - Support 'sa' for stack address.
 - Use call->data instead of container_of() macro.

[fweisbec@gmail.com: Fixed conflict against latest tracing/core]

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it>
Cc: Roland McGrath <roland@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-27 02:31:54 +02:00
H. Peter Anvin
b855192c08 Merge branch 'x86/urgent' into x86/pat
Reason: Change to is_new_memtype_allowed() in x86/urgent

Resolved semantic conflicts in:

	 arch/x86/mm/pat.c
	 arch/x86/mm/ioremap.c

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-26 17:24:28 -07:00
David S. Miller
31ffe249e5 net: Temporarily backout SKB sources tracer.
Steven Rostedt has suggested that Neil work with the tracing
folks, trying to use TRACE_EVENT as the mechanism for
implementation.  And if that doesn't workout we can investigate
other solutions such as that one which was tried here.

This reverts the following 2 commits:

5a165657be
("net: skb ftracer - Add config option to enable new ftracer (v3)")

9ec04da748
("net: skb ftracer - Add actual ftrace code to kernel (v3)")

Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-26 16:32:37 -07:00
Masami Hiramatsu
d93f12f3f4 tracing: Introduce TRACE_FIELD_ZERO() macro
Use TRACE_FIELD_ZERO(type, item) instead of TRACE_FIELD_ZERO_CHAR(item).
This also includes a typo fix of TRACE_ZERO_CHAR() macro.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it>
Cc: Roland McGrath <roland@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
LKML-Reference: <20090813203501.31965.30172.stgit@localhost.localdomain>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-27 00:46:40 +02:00
Masami Hiramatsu
bd1a5c849b tracing: Ftrace dynamic ftrace_event_call support
Add dynamic ftrace_event_call support to ftrace. Trace engines can add
new ftrace_event_call to ftrace on the fly. Each operator function of
the call takes an ftrace_event_call data structure as an argument,
because these functions may be shared among several ftrace_event_calls.

Changes from v13:
 - Define remove_subsystem_dir() always (revirt a2ca5e03), because
   trace_remove_event_call() uses it.
 - Modify syscall tracer because of ftrace_event_call change.

[fweisbec@gmail.com: Fixed conflict against latest tracing/core]

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it>
Cc: Roland McGrath <roland@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
LKML-Reference: <20090813203453.31965.71901.stgit@localhost.localdomain>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-27 00:46:40 +02:00
Jason Baron
57421dbbdc tracing: Convert event tracing code to use NR_syscalls
Convert the syscalls event tracing code to use NR_syscalls, instead of
FTRACE_SYSCALL_MAX. NR_syscalls is standard accross most arches, and
reduces code confusion/complexity.

Signed-off-by: Jason Baron <jbaron@redhat.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Jiaying Zhang <jiayingz@google.com>
Cc: Martin Bligh <mbligh@google.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Josh Stone <jistone@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anwin <hpa@zytor.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
LKML-Reference: <9b4f1a84ecae57cc6599412772efa36f0d2b815b.1251146513.git.jbaron@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-26 21:30:02 +02:00
Hendrik Brueckner
cc3b13c11c tracing: Don't trace kernel thread syscalls
Kernel threads don't call syscalls using the sysenter/sysexit
path. Instead they directly call the sys_* or do_* functions
that implement the syscalls inside the kernel.

The current syscall tracepoints only bind the sysenter/sysexit
path, then it has no effect to trace the kernel thread calls
to syscalls in that path.
Setting the TIF_SYSCALL_TRACEPOINT flag is then useless for these.

Actually there is only one case when a kernel thread can reach the
usual syscall exit tracing path: when we create a kernel thread, the
child comes to ret_from_fork and is the fork() return is then traced.
But this information alone is useless, then we don't want to set the
TIF flags for these threads.

Kernel threads have task_struct->mm set to NULL.
(Thanks to Heiko for that hint ;-)
The idea is then to check the mm field in syscall_regfunc() and
set the flag accordingly.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Jiaying Zhang <jiayingz@google.com>
Cc: Martin Bligh <mbligh@google.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
LKML-Reference: <20090825160237.GG4639@cetus.boeblingen.de.ibm.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-26 21:29:52 +02:00
Hendrik Brueckner
cd0980fc8a tracing: Check invalid syscall nr while tracing syscalls
Most arch syscall_get_nr() implementations returns -1 if the syscall
number is not valid.  Accessing the bit field without a check might
result in a kernel oops (at least I saw it on s390 for ftrace selftest).

Before this change, this problem did not occur, because the invalid
syscall number (-1) caused syscall_nr_to_meta() to return NULL.

There are at least two scenarios where syscall_get_nr() can return -1:

1. For example, ptrace stores an invalid syscall number, and thus,
   tracing code resets it.
   (see do_syscall_trace_enter in arch/s390/kernel/ptrace.c)

2. The syscall_regfunc() (kernel/tracepoint.c) sets the
   TIF_SYSCALL_FTRACE (now: TIF_SYSCALL_TRACEPOINT) flag for all threads
   which include kernel threads.
   However, the ftrace selftest triggers a kernel oops when testing
   syscall trace points:
      - The kernel thread is started as ususal (do_fork()),
      - tracing code sets TIF_SYSCALL_FTRACE,
      - the ret_from_fork() function is triggered and starts
	ftrace_syscall_exit() with an invalid syscall number.

To avoid these scenarios, I suggest to check the syscall_nr.

For instance, the ftrace selftest fails for s390 (with config option
CONFIG_FTRACE_SYSCALLS set) and produces the following kernel oops.

Unable to handle kernel pointer dereference at virtual kernel address 2000000000

Oops: 0038 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 Not tainted 2.6.31-rc6-next-20090819-dirty #18
Process kthreadd (pid: 818, task: 000000003ea207e8, ksp: 000000003e813eb8)
Krnl PSW : 0704100180000000 00000000000ea54c (ftrace_syscall_exit+0x58/0xdc)
           R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:1 PM:0 EA:3
Krnl GPRS: 0000000000000000 00000000000e0000 ffffffffffffffff 20000000008c2650
           0000000000000007 0000000000000000 0000000000000000 0000000000000000
           0000000000000000 0000000000000000 ffffffffffffffff 000000003e813d78
           000000003e813f58 0000000000505ba8 000000003e813e18 000000003e813d78
Krnl Code: 00000000000ea540: e330d0000008       ag      %r3,0(%r13)
           00000000000ea546: a7480007           lhi     %r4,7
           00000000000ea54a: 1442               nr      %r4,%r2
          >00000000000ea54c: e31030000090       llgc    %r1,0(%r3)
           00000000000ea552: 5410d008           n       %r1,8(%r13)
           00000000000ea556: 8a104000           sra     %r1,0(%r4)
           00000000000ea55a: 5410d00c           n       %r1,12(%r13)
           00000000000ea55e: 1211               ltr     %r1,%r1
Call Trace:
([<0000000000000000>] 0x0)
 [<000000000001fa22>] do_syscall_trace_exit+0x132/0x18c
 [<000000000002d0c4>] sysc_return+0x0/0x8
 [<000000000001c738>] kernel_thread_starter+0x0/0xc
Last Breaking-Event-Address:
 [<00000000000ea51e>] ftrace_syscall_exit+0x2a/0xdc

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Jiaying Zhang <jiayingz@google.com>
Cc: Martin Bligh <mbligh@google.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
LKML-Reference: <20090825125027.GE4639@cetus.boeblingen.de.ibm.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-26 21:29:48 +02:00
Ingo Molnar
35dce1a99d Merge branch 'tracing/core' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into tracing/core
Conflicts:
	include/linux/tracepoint.h

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-26 08:29:02 +02:00
Randy Dunlap
90cba64a5f timer.c: Fix S/390 comments
Fix typos and add omitted words.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: akpm <akpm@linux-foundation.org>
Cc: linux390@de.ibm.com
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
LKML-Reference: <20090825143541.43fc2ed8.randy.dunlap@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-26 08:07:31 +02:00
Zhaolei
5079f3261f ftrace: Move setting of clock-source out of options
There are many clock sources for the tracing system but we can only
enable/disable one at a time with the trace/options file.
We can move the setting of clock-source out of options and add a separate
file for it:
 # cat trace_clock
 [local] global
 # echo global > trace_clock
 # cat trace_clock
 local [global]

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
LKML-Reference: <4A939D08.6050604@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-08-26 00:32:08 -04:00
Li Zefan
87a342f5db tracing/filters: Support filtering for char * strings
Usually, char * entries are dangerous in traces because the string
can be released whereas a pointer to it can still wait to be read from
the ring buffer.

But sometimes we can assume it's safe, like in case of RO data
(eg: __file__ or __line__, used in bkl trace event). If these RO data
are in a module and so is the call to the trace event, then it's safe,
because the ring buffer will be flushed once this module get unloaded.

To allow char * to be treated as a string:

	TRACE_EVENT(...,

		TP_STRUCT__entry(
			__field_ext(const char *, name, FILTER_PTR_STRING)
			...
		)

		...
	);

The filtering will not dereference "char *" unless the developer
explicitly sets FILTER_PTR_STR in __field_ext.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4A7B9287.90205@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-08-26 00:32:07 -04:00
Li Zefan
43b51ead3f tracing/filters: Add __field_ext() to TRACE_EVENT
Add __field_ext(), so a field can be assigned to a specific
filter_type, which matches a corresponding filter function.

For example, a later patch will allow this:
	__field_ext(const char *, str, FILTER_PTR_STR);

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4A7B9272.6050709@cn.fujitsu.com>

[
  Fixed a -1 to FILTER_OTHER
  Forward ported to latest kernel.
]

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-08-26 00:32:06 -04:00
Li Zefan
aa38e9fc3e tracing/filters: Add filter_type to struct ftrace_event_field
The type of a field is stored as a string in @type, and here
we add @filter_type which is an enum value.

This prepares for later patches, so we can specifically assign
different @filter_type for the same @type.

For example normally a "char *" field is treated as a ptr,
but we may want it to be treated as a string when doing filting.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4A7B925E.9030605@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-08-26 00:32:06 -04:00
Josh Stone
1c569f0264 tracing: Create generic syscall TRACE_EVENTs
This converts the syscall_enter/exit tracepoints into TRACE_EVENTs, so
you can have generic ftrace events that capture all system calls with
arguments and return values.  These generic events are also renamed to
sys_enter/exit, so they're more closely aligned to the specific
sys_enter_foo events.

Signed-off-by: Josh Stone <jistone@redhat.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Jiaying Zhang <jiayingz@google.com>
Cc: Martin Bligh <mbligh@google.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
LKML-Reference: <1251150194-1713-5-git-send-email-jistone@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-26 00:41:48 +02:00
Josh Stone
9741987586 tracing: Move tracepoint callbacks from declaration to definition
It's not strictly correct for the tracepoint reg/unreg callbacks to
occur when a client is hooking up, because the actual tracepoint may not
be present yet.  This happens to be fine for syscall, since that's in
the core kernel, but it would cause problems for tracepoints defined in
a module that hasn't been loaded yet.  It also means the reg/unreg has
to be EXPORTed for any modules to use the tracepoint (as in SystemTap).

This patch removes DECLARE_TRACE_WITH_CALLBACK, and instead introduces
DEFINE_TRACE_FN which stores the callbacks in struct tracepoint.  The
callbacks are used now when the active state of the tracepoint changes
in set_tracepoint & disable_tracepoint.

This also introduces TRACE_EVENT_FN, so ftrace events can also provide
registration callbacks if needed.

Signed-off-by: Josh Stone <jistone@redhat.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Jiaying Zhang <jiayingz@google.com>
Cc: Martin Bligh <mbligh@google.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
LKML-Reference: <1251150194-1713-4-git-send-email-jistone@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-26 00:36:41 +02:00
Josh Stone
3d27d8cb34 tracing: Make syscall tracepoints conditional
The syscall enter/exit tracepoints are only supported on archs that
HAVE_SYSCALL_TRACEPOINTS, so the declarations should be #ifdef'ed.
Also, the definition of syscall_regfunc and syscall_unregfunc should
depend on this same config, rather than the ftrace-specific one.

Signed-off-by: Josh Stone <jistone@redhat.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Jiaying Zhang <jiayingz@google.com>
Cc: Martin Bligh <mbligh@google.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
LKML-Reference: <1251150194-1713-3-git-send-email-jistone@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-26 00:24:19 +02:00
Josh Stone
6670000119 tracing: Rename FTRACE_SYSCALLS for tracepoints
s/HAVE_FTRACE_SYSCALLS/HAVE_SYSCALL_TRACEPOINTS/g
s/TIF_SYSCALL_FTRACE/TIF_SYSCALL_TRACEPOINT/g

The syscall enter/exit tracing is no longer specific to just ftrace, so
they now have names that reflect their tie to tracepoints instead.

Signed-off-by: Josh Stone <jistone@redhat.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Jiaying Zhang <jiayingz@google.com>
Cc: Martin Bligh <mbligh@google.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
LKML-Reference: <1251150194-1713-2-git-send-email-jistone@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-26 00:17:35 +02:00
Linus Torvalds
9c93768866 Merge branch 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf_counter: Fix typo in read() output generation
  perf tools: Check perf.data owner
2009-08-25 11:24:37 -07:00
Linus Torvalds
44afa9a4b8 Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  clockevent: Prevent dead lock on clockevents_lock
  timers: Drop write permission on /proc/timer_list
2009-08-25 11:24:04 -07:00
Linus Torvalds
7d63e6359a Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  tracing: Fix too large stack usage in do_one_initcall()
  tracing: handle broken names in ftrace filter
  ftrace: Unify effect of writing to trace_options and option/*
2009-08-25 11:23:43 -07:00
Paul E. McKenney
c935a331c8 rcu: Add #ifdef to suppress __rcu_offline_cpu() warning in !HOTPLUG_CPU builds
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Paul Mundt <lethal@linux-sh.org>
LKML-Reference: <20090825154025.GD6616@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-25 20:20:03 +02:00
Anirban Sinha
d88cb58232 tracing: Eliminate code duplication in kernel/tracepoint.c
Signed-off-by: Anirban Sinha <asinha@zeugmasystems.com>
Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: "Oleg Nesterov" <oleg@tv-sign.ru>
LKML-Reference: <DDFD17CC94A9BD49A82147DDF7D545C501EA9047@exchange.ZeugmaSystems.local>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-25 16:15:12 +02:00
Ingo Molnar
daedc71836 Merge commit 'v2.6.31-rc7' into irq/core
Merge reason: move from an -rc2 base to -rc7.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-25 10:04:32 +02:00
Peter Zijlstra
a4be7c2778 perf_counter: Allow sharing of output channels
Provide the ability to configure a counter to send its output
to another (already existing) counter's output stream.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: stephane eranian <eranian@googlemail.com>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20090819092023.980284148@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-25 09:36:13 +02:00
Paul Mackerras
fa289beca9 perf_counter: Start counting time enabled when group leader gets enabled
Currently, if a group is created where the group leader is
initially disabled but a non-leader member is initially
enabled, and then the leader is subsequently enabled some time
later, the time_enabled for the non-leader member will reflect
the whole time since it was created, not just the time since
the leader was enabled.

This is incorrect, because all of the members are effectively
disabled while the leader is disabled, since none of the
members can go on the PMU if the leader can't.

Thus we have to update the ->tstamp_enabled for all the enabled
group members when a group leader is enabled, so that the
time_enabled computation only counts the time since the leader
was enabled.

Similarly, when disabling a group leader we have to update the
time_enabled and time_running for all of the group members.

Also, in update_counter_times, we have to treat a counter whose
group leader is disabled as being disabled.

Reported-by: Stephane Eranian <eranian@googlemail.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: <stable@kernel.org>
LKML-Reference: <19091.29664.342227.445006@drongo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-25 09:34:38 +02:00
Hiroshi Shimamoto
36d47481b3 timekeeping: Fix invalid getboottime() value
Don't use timespec_add_safe() with wall_to_monotonic, because
wall_to_monotonic has negative values which will cause overflow
in timespec_add_safe(). That makes btime in /proc/stat invalid.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Daniel Walker <dwalker@fifo99.com>
LKML-Reference: <4A937FDE.4050506@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-25 09:09:02 +02:00
Paul E. McKenney
33f76148ce rcu: Add CPU-offline processing for single-node configurations
Add preemptable-RCU plugin to handle the CPU-offline
processing.

An additional plugin is forthcoming to handle multinode RCU
trees, but this current plugin works for configurations up to
32 CPUs (64 CPUs for 64-bit kernels).

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <12511321213336-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-24 20:37:04 +02:00
Michal Schmidt
d8e180dcd5 bsdacct: switch credentials for writing to the accounting file
When process accounting is enabled, every exiting process writes a log to
the account file.  In addition, every once in a while one of the exiting
processes checks whether there's enough free space for the log.

SELinux policy may or may not allow the exiting process to stat the fs.
So unsuspecting processes start generating AVC denials just because
someone enabled process accounting.

For these filesystem operations, the exiting process's credentials should
be temporarily switched to that of the process which enabled accounting,
because it's really that process which wanted to have the accounting
information logged.

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Morris <jmorris@namei.org>
2009-08-24 11:33:40 +10:00
Paul E. McKenney
6b3ef48adf rcu: Remove CONFIG_PREEMPT_RCU
Now that CONFIG_TREE_PREEMPT_RCU is in place, there is no
further need for CONFIG_PREEMPT_RCU.  Remove it, along with
whatever subtle bugs it may (or may not) contain.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <125097461396-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-23 10:32:40 +02:00
Paul E. McKenney
f41d911f8c rcu: Merge preemptable-RCU functionality into hierarchical RCU
Create a kernel/rcutree_plugin.h file that contains definitions
for preemptable RCU (or, under the #else branch of the #ifdef,
empty definitions for the classic non-preemptable semantics).
These definitions fit into plugins defined in kernel/rcutree.c
for this purpose.

This variant of preemptable RCU uses a new algorithm whose
read-side expense is roughly that of classic hierarchical RCU
under CONFIG_PREEMPT. This new algorithm's update-side expense
is similar to that of classic hierarchical RCU, and, in absence
of read-side preemption or blocking, is exactly that of classic
hierarchical RCU.  Perhaps more important, this new algorithm
has a much simpler implementation, saving well over 1,000 lines
of code compared to mainline's implementation of preemptable
RCU, which will hopefully be retired in favor of this new
algorithm.

The simplifications are obtained by maintaining per-task
nesting state for running tasks, and using a simple
lock-protected algorithm to handle accounting when tasks block
within RCU read-side critical sections, making use of lessons
learned while creating numerous user-level RCU implementations
over the past 18 months.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <12509746134003-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-23 10:32:40 +02:00
Paul E. McKenney
a157229cab rcu: Simplify rcu_pending()/rcu_check_callbacks() API
All calls from outside RCU are of the form:

	if (rcu_pending(cpu))
		rcu_check_callbacks(cpu, user);

This is silly, instead we put a call to rcu_pending() in
rcu_check_callbacks(), and then make the outside calls be to
rcu_check_callbacks().  This cuts down on the code a bit and
also gives the compiler a better chance of optimizing.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <125097461311-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-23 10:32:39 +02:00
Paul E. McKenney
22f00b69f6 rcu: Use debugfs_remove_recursive() simplify code.
Suggested by Josh Triplett.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
LKML-Reference: <12509746132173-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-23 10:32:39 +02:00
Paul E. McKenney
65cf8f866f rcu: Merge per-RCU-flavor initialization into pre-existing macro
Rename the RCU_DATA_PTR_INIT() macro to RCU_INIT_FLAVOR() and
make it do the rcu_init_one() and rcu_boot_init_percpu_data()
calls.  Merge the loop that was in the original macro with the
loops that were in __rcu_init().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <12509746133916-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-23 10:32:38 +02:00
Paul E. McKenney
5699ed8fcb rcu: Fix online/offline indication for rcudata.csv trace file
The heading said "Online?", but the column had "Y" for offline
CPUs and "N" for online CPUs.  Swap the "Y" and "N" to match
the heading.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <12509746132841-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-23 10:32:38 +02:00
Paul E. McKenney
d6714c22b4 rcu: Renamings to increase RCU clarity
Make RCU-sched, RCU-bh, and RCU-preempt be underlying
implementations, with "RCU" defined in terms of one of the
three.  Update the outdated rcu_qsctr_inc() names, as these
functions no longer increment anything.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <12509746132696-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-23 10:32:37 +02:00
Paul E. McKenney
9f77da9f40 rcu: Move private definitions from include/linux/rcutree.h to kernel/rcutree.h
Some information hiding that makes it easier to merge
preemptability into rcutree without descending into #include
hell.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <1250974613373-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-23 10:32:36 +02:00
Rafael J. Wysocki
5e928f77a0 PM: Introduce core framework for run-time PM of I/O devices (rev. 17)
Introduce a core framework for run-time power management of I/O
devices.  Add device run-time PM fields to 'struct dev_pm_info'
and device run-time PM callbacks to 'struct dev_pm_ops'.  Introduce
a run-time PM workqueue and define some device run-time PM helper
functions at the core level.  Document all these things.

Special thanks to Alan Stern for his help with the design and
multiple detailed reviews of the pereceding versions of this patch
and to Magnus Damm for testing feedback.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@igel.co.jp>
2009-08-23 00:04:44 +02:00
Suresh Siddha
d0af9eed5a x86, pat/mtrr: Rendezvous all the cpus for MTRR/PAT init
SDM Vol 3a section titled "MTRR considerations in MP systems" specifies
the need for synchronizing the logical cpu's while initializing/updating
MTRR.

Currently Linux kernel does the synchronization of all cpu's only when
a single MTRR register is programmed/updated. During an AP online
(during boot/cpu-online/resume)  where we initialize all the MTRR/PAT registers,
we don't follow this synchronization algorithm.

This can lead to scenarios where during a dynamic cpu online, that logical cpu
is initializing MTRR/PAT with cache disabled (cr0.cd=1) etc while other logical
HT sibling continue to run (also with cache disabled because of cr0.cd=1
on its sibling).

Starting from Westmere, VMX transitions with cr0.cd=1 don't work properly
(because of some VMX performance optimizations) and the above scenario
(with one logical cpu doing VMX activity and another logical cpu coming online)
can result in system crash.

Fix the MTRR initialization by doing rendezvous of all the cpus. During
boot and resume, we delay the MTRR/PAT init for APs till all the
logical cpu's come online and the rendezvous process at the end of AP's bringup,
will initialize the MTRR/PAT for all AP's.

For dynamic single cpu online, we synchronize all the logical cpus and
do the MTRR/PAT init on the AP that is coming online.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-21 16:25:55 -07:00
Suresh Siddha
269c861baa generic-ipi: Allow cpus not yet online to call smp_call_function with irqs disabled
Because of deadlock possiblities smp_call_function() is not allowed to
be called with interrupts disabled. Add an exception for the cpu not
yet online, as no one else can send smp call function interrupt to this
cpu that is not yet online and as such deadlock condition is not possible.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-21 16:25:43 -07:00
john stultz
da15cfdae0 time: Introduce CLOCK_REALTIME_COARSE
After talking with some application writers who want very fast, but not
fine-grained timestamps, I decided to try to implement new clock_ids
to clock_gettime(): CLOCK_REALTIME_COARSE and CLOCK_MONOTONIC_COARSE
which returns the time at the last tick. This is very fast as we don't
have to access any hardware (which can be very painful if you're using
something like the acpi_pm clocksource), and we can even use the vdso
clock_gettime() method to avoid the syscall. The only trade off is you
only get low-res tick grained time resolution.

This isn't a new idea, I know Ingo has a patch in the -rt tree that made
the vsyscall gettimeofday() return coarse grained time when the
vsyscall64 sysctrl was set to 2. However this affects all applications
on a system.

With this method, applications can choose the proper speed/granularity
trade-off for themselves.

Signed-off-by: John Stultz <johnstul@us.ibm.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: nikolag@ca.ibm.com
Cc: Darren Hart <dvhltc@us.ibm.com>
Cc: arjan@infradead.org
Cc: jonathan@jonmasters.org
LKML-Reference: <1250734414.6897.5.camel@localhost.localdomain>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-21 21:43:46 +02:00
Peter Zijlstra
4464fcaa9c perf_counter: Fix typo in read() output generation
When you iterate a list, using the iterator is useful.

Before:

   ID: 5
   ID: 5
   ID: 5
   ID: 5
   EVNT: 0x40088b scale: nan ID: 5 CNT: 1006252 ID: 6 CNT: 1011090 ID: 7 CNT: 1011196 ID: 8 CNT: 1011095
   EVNT: 0x40088c scale: 1.000000 ID: 5 CNT: 2003065 ID: 6 CNT: 2011671 ID: 7 CNT: 2012620 ID: 8 CNT: 2013479
   EVNT: 0x40088c scale: 1.000000 ID: 5 CNT: 3002390 ID: 6 CNT: 3015996 ID: 7 CNT: 3018019 ID: 8 CNT: 3020006
   EVNT: 0x40088b scale: 1.000000 ID: 5 CNT: 4002406 ID: 6 CNT: 4021120 ID: 7 CNT: 4024241 ID: 8 CNT: 4027059

After:

   ID: 1
   ID: 2
   ID: 3
   ID: 4
   EVNT: 0x400889 scale: nan ID: 1 CNT: 1005270 ID: 2 CNT: 1009833 ID: 3 CNT: 1010065 ID: 4 CNT: 1010088
   EVNT: 0x400898 scale: nan ID: 1 CNT: 2001531 ID: 2 CNT: 2022309 ID: 3 CNT: 2022470 ID: 4 CNT: 2022627
   EVNT: 0x400888 scale: 0.489467 ID: 1 CNT: 3001261 ID: 2 CNT: 3027088 ID: 3 CNT: 3027941 ID: 4 CNT: 3028762

Reported-by: stephane eranian <eranian@googlemail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey J Ashford <cjashfor@us.ibm.com>
Cc: perfmon2-devel <perfmon2-devel@lists.sourceforge.net>
LKML-Reference: <1250867976.7538.73.camel@twins>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-21 18:00:35 +02:00
Peter Zijlstra
a8af7246c1 sched: Avoid division by zero
Patch a5004278f0 (sched: Fix
cgroup smp fairness) introduced the possibility of a
divide-by-zero because load-balancing is not synchronized
between sched_domains.

This can cause the state of cpus to change between the first
and second loop over the sched domain in tg_shares_up().

Reported-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <1250855934.7538.30.camel@twins>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-21 14:15:10 +02:00
Hiroshi Shimamoto
cde7e5ca4e sched: Use for_each_class macro in move_one_task()
Replace for loop with the macro for_each_class to cleanup.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
LKML-Reference: <4A8A277D.4090304@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-20 13:00:30 +02:00
Li Zefan
4539f07701 tracing/syscalls: Fix the output of syscalls with no arguments
Before:

  # echo 1 > events/syscalls/sys_enter_sync/enable
  # cat events/syscalls/sys_enter_sync/format
  ...
        field:int nr;   offset:12;      size:4;

  print fmt: "# sync
  # cat trace
  ...
            sync-8950  [000]  2366.087670: sys_sync(

After:

  # echo 1 > events/syscalls/sys_enter_sync/enable
  # cat events/syscalls/sys_enter_sync/format
  ...
        field:int nr;   offset:12;      size:4;

  print fmt: ""
  # sync
  # cat trace
            sync-2134  [001]   136.780735: sys_sync()

Reported-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
LKML-Reference: <4A8D05AF.20103@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-20 12:12:22 +02:00
Michael Ellerman
a15098c90d powerpc: Enable GCOV
Make it possible to enable GCOV code coverage measurement on powerpc.

Lightly tested on 64-bit, seems to work as expected.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:29:28 +10:00
James Morris
ece13879e7 Merge branch 'master' into next
Conflicts:
	security/Kconfig

Manual fix.

Signed-off-by: James Morris <jmorris@namei.org>
2009-08-20 09:18:42 +10:00
Linus Torvalds
d46c7d9ab8 Merge branch 'perfcounters-fixes-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perfcounters-fixes-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf tools: Make 'make html' work
  perf annotate: Fix segmentation fault
  perf_counter: Fix the PARISC build
  perf_counter: Check task on counter read IPI
  perf: Rename perf-examples.txt to examples.txt
  perf record: Fix typo in pid_synthesize_comm_event
2009-08-19 09:43:19 -07:00
Suresh Siddha
f833bab87f clockevent: Prevent dead lock on clockevents_lock
Currently clockevents_notify() is called with interrupts enabled at
some places and interrupts disabled at some other places.

This results in a deadlock in this scenario.

cpu A holds clockevents_lock in clockevents_notify() with irqs enabled
cpu B waits for clockevents_lock in clockevents_notify() with irqs disabled
cpu C doing set_mtrr() which will try to rendezvous of all the cpus.

This will result in C and A come to the rendezvous point and waiting
for B. B is stuck forever waiting for the spinlock and thus not
reaching the rendezvous point.

Fix the clockevents code so that clockevents_lock is taken with
interrupts disabled and thus avoid the above deadlock.

Also call lapic_timer_propagate_broadcast() on the destination cpu so
that we avoid calling smp_call_function() in the clockevents notifier
chain.

This issue left us wondering if we need to change the MTRR rendezvous
logic to use stop machine logic (instead of smp_call_function) or add
a check in spinlock debug code to see if there are other spinlocks
which gets taken under both interrupts enabled/disabled conditions.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: "Pallipadi Venkatesh" <venkatesh.pallipadi@intel.com>
Cc: "Brown Len" <len.brown@intel.com>
LKML-Reference: <1250544899.2709.210.camel@sbs-t61.sc.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-19 18:15:10 +02:00
Li Zefan
540b7b8d65 tracing/syscalls: Add filtering support
Add filtering support for syscall events:

 # echo 'mode == 0666' > events/syscalls/sys_enter_open
 # echo 'ret == 0' > events/syscalls/sys_exit_open
 # echo 1 > events/syscalls/sys_enter_open
 # echo 1 > events/syscalls/sys_exit_open
 # cat trace
 ...
   modprobe-3084 [001] 117.463140: sys_open(filename: 917d3e8, flags: 0, mode: 1b6)
   modprobe-3084 [001] 117.463176: sys_open -> 0x0
       less-3086 [001] 117.510455: sys_open(filename: 9c6bdb8, flags: 8000, mode: 1b6)
   sendmail-2574 [001] 122.145840: sys_open(filename: b807a365, flags: 0, mode: 1b6)
 ...

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4A8BAFCB.1040006@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-19 15:02:24 +02:00
Li Zefan
e647d6b314 tracing/events: Add trace_define_common_fields()
Extract duplicate code. Also prepare for the later patch.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4A8BAFB8.1010304@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-19 15:02:24 +02:00
Li Zefan
14be96c971 tracing/events: Add ftrace_event_call param to define_fields()
This parameter is needed by syscall events to add define_fields()
handler.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4A8BAF90.6060801@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-19 15:02:23 +02:00
Li Zefan
10a5b66f62 tracing/syscalls: Add fields format for exit events
Add "format" file for syscall exit events:

 # cat events/syscalls/sys_exit_open/format
 name: sys_exit_open
 ID: 344
 format:
         field:unsigned short common_type;       offset:0;       size:2;
         field:unsigned char common_flags;       offset:2;       size:1;
         field:unsigned char common_preempt_count;       offset:3;       size:1;
         field:int common_pid;   offset:4;       size:4;
         field:int common_tgid;  offset:8;       size:4;

         field:int nr;   offset:12;      size:4;
         field:unsigned long ret;        offset:16;      size:4;

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4A8BAF61.3060307@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-19 15:02:23 +02:00
Li Zefan
e6971969c3 tracing/syscalls: Fix fields format for enter events
The "format" file of a trace event is originally for parsers to
parse ftrace binary output.

But the "format" file of a syscall event can only be used by
perfcounter, because it describes the format of struct
syscall_enter_record not struct syscall_trace_enter.

To fix this, we remove struct syscall_enter_record, and then
struct syscall_trace_enter will be used by both perf profile
and ftrace.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4A8BAF39.1030404@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-19 15:02:22 +02:00
Paul E. McKenney
1423cc033d rcu: Delay rcu_barrier() wait until beginning of next CPU-hotunplug operation.
Ingo Molnar reported this lockup:

 [  200.380003] Hangcheck: hangcheck value past margin!
 [  248.192003] INFO: task S99local:2974 blocked for more than 120 seconds.
 [  248.194532] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
 [  248.202330] S99local      D 0000000c  6256  2974   2687 0x00000000
 [  248.208929]  9c7ebe90 00000086 6b67ef8b 0000000c 9f25a610 81a69869 00000001 820b6990
 [  248.216123]  820b6990 820b6990 9c6e4c20 9c6e4eb4 82c78990 00000000 6b993559 0000000c
 [  248.220616]  9c7ebe90 8105f22a 9c6e4eb4 9c6e4c20 00000001 9c7ebe98 9c7ebeb4 81a65cb3
 [  248.229990] Call Trace:
 [  248.234049]  [<81a69869>] ? _spin_unlock_irqrestore+0x22/0x37
 [  248.239769]  [<8105f22a>] ? prepare_to_wait+0x48/0x4e
 [  248.244796]  [<81a65cb3>] rcu_barrier_cpu_hotplug+0xaa/0xc9
 [  248.250343]  [<8105f029>] ? autoremove_wake_function+0x0/0x38
 [  248.256063]  [<81062cf2>] notifier_call_chain+0x49/0x71
 [  248.261263]  [<81062da0>] raw_notifier_call_chain+0x11/0x13
 [  248.266809]  [<81a0b475>] _cpu_down+0x272/0x288
 [  248.271316]  [<81a0b4d5>] cpu_down+0x4a/0xa2
 [  248.275563]  [<81a0c48a>] store_online+0x2a/0x5e
 [  248.280156]  [<81a0c460>] ? store_online+0x0/0x5e
 [  248.284836]  [<814ddc35>] sysdev_store+0x20/0x28
 [  248.289429]  [<8112e403>] sysfs_write_file+0xb8/0xe3
 [  248.294369]  [<8112e34b>] ? sysfs_write_file+0x0/0xe3
 [  248.299396]  [<810e4c8f>] vfs_write+0x91/0x120
 [  248.303817]  [<810e4dc1>] sys_write+0x40/0x65
 [  248.308150]  [<81002d73>] sysenter_do_call+0x12/0x28

This change moves an RCU grace period delay off of the
critical path for CPU-hotunplug operations.

Since RCU callback migration is only performed on
CPU-hotunplug operations, and since the rcu_barrier() race is
provoked only by consecutive CPU-hotunplug operations, it is
not necessary to delay the end of a given CPU-hotunplug
operation.

We can instead choose to delay the beginning of the next
CPU-hotunplug operation.

Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josht@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: hugh.dickins@tiscali.co.uk
Cc: benh@kernel.crashing.org
LKML-Reference: <20090819060614.GA14383@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-19 13:58:54 +02:00
Martin Schwidefsky
01548f4d3e clocksource: Avoid clocksource watchdog circular locking dependency
stop_machine from a multithreaded workqueue is not allowed because
of a circular locking dependency between cpu_down and the workqueue
execution. Use a kernel thread to do the clocksource downgrade.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: john stultz <johnstul@us.ibm.com>
LKML-Reference: <20090818170942.3ab80c91@skybase>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-19 12:00:56 +02:00
Thomas Gleixner
d0981a1b21 clocksource: Protect the watchdog rating changes with clocksource_mutex
Martin pointed out that commit 6ea41d2529 (clocksource: Call
clocksource_change_rating() outside of watchdog_lock) has a
theoretical reference count problem. The calls to
clocksource_change_rating() are now done outside of the clocksource
mutex and outside of the watchdog lock. A concurrent
clocksource_unregister() could remove the clock.

Split out the code which changes the rating from
clocksource_change_rating() into __clocksource_change_rating().

Protect the clocksource_watchdog_work() code sequence with the
clocksource_mutex() and call __clocksource_change_rating().

LKML-Reference: <alpine.LFD.2.00.0908171038420.2782@localhost.localdomain>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-08-19 11:42:48 +02:00
Steven Rostedt
de481560eb kconfig: keep config.gz around even if CONFIG_IKCONFIG_PROC is not set
If CONFIG_IKCONFIG is set but CONFIG_IKCONFIG_PROC is not, then
gcc will optimize the config.gz out, because nobody uses it.

This patch adds "__used" to the config.gz data to keep it around so that
code like extract-ikconfig can still find it.

[ Impact: allow extract-ikconfig to find config.gz ]

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-08-18 22:01:08 -04:00
Jiri Olsa
eda1e32855 tracing: handle broken names in ftrace filter
If one filter item (for set_ftrace_filter and set_ftrace_notrace) is being
setup by more than 1 consecutive writes (FTRACE_ITER_CONT flag), it won't
be handled corretly.

I used following program to test/verify:

[snip]
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string.h>

int main(int argc, char **argv)
{
        int fd, i;
        char *file = argv[1];

        if (-1 == (fd = open(file, O_WRONLY))) {
                perror("open failed");
                return -1;
        }

        for(i = 0; i < (argc - 2); i++) {
                int len = strlen(argv[2+i]);
                int cnt, off = 0;

                while(len) {
                        cnt = write(fd, argv[2+i] + off, len);
                        len -= cnt;
                        off += cnt;
                }
        }

        close(fd);
        return 0;
}
[snip]

before change:
sh-4.0# echo > ./set_ftrace_filter
sh-4.0# /test ./set_ftrace_filter "sys" "_open "
sh-4.0# cat ./set_ftrace_filter
#### all functions enabled ####
sh-4.0#

after change:
sh-4.0# echo > ./set_ftrace_notrace
sh-4.0# test ./set_ftrace_notrace "sys" "_open "
sh-4.0# cat ./set_ftrace_notrace
sys_open
sh-4.0#

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
LKML-Reference: <20090811152904.GA26065@jolsa.lab.eng.brq.redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-08-18 20:39:48 -04:00
KOSAKI Motohiro
0753ba01e1 mm: revert "oom: move oom_adj value"
The commit 2ff05b2b (oom: move oom_adj value) moveed the oom_adj value to
the mm_struct.  It was a very good first step for sanitize OOM.

However Paul Menage reported the commit makes regression to his job
scheduler.  Current OOM logic can kill OOM_DISABLED process.

Why? His program has the code of similar to the following.

	...
	set_oom_adj(OOM_DISABLE); /* The job scheduler never killed by oom */
	...
	if (vfork() == 0) {
		set_oom_adj(0); /* Invoked child can be killed */
		execve("foo-bar-cmd");
	}
	....

vfork() parent and child are shared the same mm_struct.  then above
set_oom_adj(0) doesn't only change oom_adj for vfork() child, it's also
change oom_adj for vfork() parent.  Then, vfork() parent (job scheduler)
lost OOM immune and it was killed.

Actually, fork-setting-exec idiom is very frequently used in userland program.
We must not break this assumption.

Then, this patch revert commit 2ff05b2b and related commit.

Reverted commit list
---------------------
- commit 2ff05b2b4e (oom: move oom_adj value from task_struct to mm_struct)
- commit 4d8b9135c3 (oom: avoid unnecessary mm locking and scanning for OOM_DISABLE)
- commit 8123681022 (oom: only oom kill exiting tasks with attached memory)
- commit 933b787b57 (mm: copy over oom_adj value at fork time)

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-18 16:31:13 -07:00
Huang Weiyi
b08dc3eba0 Security/SELinux: remove duplicated #include
Remove duplicated #include('s) in
  kernel/sysctl.c

Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-08-19 08:09:09 +10:00
Linus Torvalds
dcd94dbdaf Merge branch 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  genirq: Wake up irq thread after action has been installed
2009-08-18 13:57:38 -07:00
Andreas Herrmann
294b0c9619 sched: Consolidate definition of variable sd in __build_sched_domains
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818110229.GM29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:45 +02:00
Andreas Herrmann
0601a88d8f sched: Separate out build of NUMA sched groups from __build_sched_domains
... to further strip down __build_sched_domains().

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818110111.GL29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:44 +02:00
Andreas Herrmann
de616e36c7 sched: Separate out build of ALLNODES sched groups from __build_sched_domains
For the sake of completeness.
Now all calls to init_sched_build_groups() are contained in
build_sched_groups().

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818110013.GK29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:44 +02:00
Andreas Herrmann
86548096f2 sched: Separate out build of CPU sched groups from __build_sched_domains
... to further strip down __build_sched_domains().

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818105928.GJ29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:43 +02:00
Andreas Herrmann
a2af04cdbb sched: Separate out build of MC sched groups from __build_sched_domains
... to further strip down __build_sched_domains().

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818105838.GI29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:43 +02:00
Andreas Herrmann
0e8e85c941 sched: Separate out build of SMT sched groups from __build_sched_domains
... to further strip down __build_sched_domains().

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818105751.GH29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:42 +02:00
Andreas Herrmann
d817353555 sched: Separate out build of SMT sched domain from __build_sched_domains
... to further strip down __build_sched_domains().

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818105703.GG29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:42 +02:00
Andreas Herrmann
410c408108 sched: Separate out build of MC sched domain from __build_sched_domains
... to further strip down __build_sched_domains().

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818105614.GF29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:41 +02:00
Andreas Herrmann
87cce6622c sched: Separate out build of CPU sched domain from __build_sched_domains
... to further strip down __build_sched_domains().

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818105455.GE29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:40 +02:00
Andreas Herrmann
7f4588f3aa sched: Separate out build of NUMA sched domain from __build_sched_domains
... to further strip down __build_sched_domains().

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818105406.GD29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:40 +02:00
Andreas Herrmann
2109b99ee1 sched: Separate out allocation/free/goto-hell from __build_sched_domains
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818105300.GC29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:39 +02:00
Andreas Herrmann
49a02c514d sched: Use structure to store local data in __build_sched_domains
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818105152.GB29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:39 +02:00
Thomas Gleixner
69ab849439 genirq: Wake up irq thread after action has been installed
The wake_up_process() of the new irq thread in __setup_irq() is too
early as the irqaction is not yet fully initialized especially
action->irq is not yet set. The interrupt thread might dereference the
wrong irq descriptor.

Move the wakeup after the action is installed and action->irq has been
set.

Reported-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Michael Buesch <mb@bu3sch.de>
2009-08-18 17:22:43 +02:00
Ingo Molnar
f738eb1b63 perf_counter: Fix the PARISC build
PARISC does not build:

/home/mingo/tip/kernel/perf_counter.c: In function 'perf_counter_index':
/home/mingo/tip/kernel/perf_counter.c:2016: error: 'PERF_COUNTER_INDEX_OFFSET' undeclared (first use in this function)
/home/mingo/tip/kernel/perf_counter.c:2016: error: (Each undeclared identifier is reported only once
/home/mingo/tip/kernel/perf_counter.c:2016: error: for each function it appears in.)

As PERF_COUNTER_INDEX_OFFSET is not defined.

Now, we could define it in the architecture - but lets also provide
a core default of 0 (which happens to be what all but one
architecture uses at the moment).

Architectures that need a different index offset should set this
value in their asm/perf_counter.h files.

Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 11:34:13 +02:00
Zhaolei
f2d84b65b9 ftrace: Unify effect of writing to trace_options and option/*
"echo noglobal-clock > trace_options" can be used to change trace
clock but "echo 0 > options/global-clock" can't. The flag toggling
will be silently accepted without actually changing the clock callback.

We can fix it by using set_tracer_flags() in
trace_options_core_write().

Changelog:
v1->v2: Simplified switch() after Li Zefan <lizf@cn.fujitsu.com>'s
        suggestion

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-18 02:07:04 +02:00