This false positive is due to field padding in struct sigqueue. When
this dynamically allocated structure is copied to the stack (in arch-
specific delivery code), kmemcheck sees a read from the padding, which
is, naturally, uninitialized.
Hide the false positive using the __GFP_NOTRACK_FALSE_POSITIVE flag.
Also made the rlimit override code a bit clearer by introducing a new
variable.
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
This gets rid of a heap of false-positive warnings from the tracer
code due to the use of bitfields.
[rebased for mainline inclusion]
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
With kmemcheck enabled, the slab allocator needs to do this:
1. Tell kmemcheck to allocate the shadow memory which stores the status of
each byte in the allocation proper, e.g. whether it is initialized or
uninitialized.
2. Tell kmemcheck which parts of memory that should be marked uninitialized.
There are actually a few more states, such as "not yet allocated" and
"recently freed".
If a slab cache is set up using the SLAB_NOTRACK flag, it will never return
memory that can take page faults because of kmemcheck.
If a slab cache is NOT set up using the SLAB_NOTRACK flag, callers can still
request memory with the __GFP_NOTRACK flag. This does not prevent the page
faults from occuring, however, but marks the object in question as being
initialized so that no warnings will ever be produced for this object.
In addition to (and in contrast to) __GFP_NOTRACK, the
__GFP_NOTRACK_FALSE_POSITIVE flag indicates that the allocation should
not be tracked _because_ it would produce a false positive. Their values
are identical, but need not be so in the future (for example, we could now
enable/disable false positives with a config option).
Parts of this patch were contributed by Pekka Enberg but merged for
atomicity.
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
[rebased for mainline inclusion]
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
General description: kmemcheck is a patch to the linux kernel that
detects use of uninitialized memory. It does this by trapping every
read and write to memory that was allocated dynamically (e.g. using
kmalloc()). If a memory address is read that has not previously been
written to, a message is printed to the kernel log.
Thanks to Andi Kleen for the set_memory_4k() solution.
Andrew Morton suggested documenting the shadow member of struct page.
Signed-off-by: Vegard Nossum <vegardno@ifi.uio.no>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
[export kmemcheck_mark_initialized]
[build fix for setup_max_cpus]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
[rebased for mainline inclusion]
Signed-off-by: Vegard Nossum <vegardno@ifi.uio.no>
Rationale: kmemcheck needs to be able to schedule a tasklet without
touching any dynamically allocated memory _at_ _all_ (since that would
lead to a recursive page fault). This tasklet is used for writing the
error reports to the kernel log.
The new scheduling function avoids touching any other tasklets by
inserting the new tasklist as the head of the "tasklet_hi" list instead
of on the tail.
Also don't wake up the softirq thread lest the scheduler access some
tracked memory and we go down with a recursive page fault.
In this case, we'd better just wait for the maximum time of 1/HZ for the
message to appear.
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
* 'for-linus' of git://linux-arm.org/linux-2.6:
kmemleak: Add the corresponding MAINTAINERS entry
kmemleak: Simple testing module for kmemleak
kmemleak: Enable the building of the memory leak detector
kmemleak: Remove some of the kmemleak false positives
kmemleak: Add modules support
kmemleak: Add kmemleak_alloc callback from alloc_large_system_hash
kmemleak: Add the vmalloc memory allocation/freeing hooks
kmemleak: Add the slub memory allocation/freeing hooks
kmemleak: Add the slob memory allocation/freeing hooks
kmemleak: Add the slab memory allocation/freeing hooks
kmemleak: Add documentation on the memory leak detector
kmemleak: Add the base support
Manual conflict resolution (with the slab/earlyboot changes) in:
drivers/char/vt.c
init/main.c
mm/slab.c
* 'perfcounters-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (574 commits)
perf_counter: Turn off by default
perf_counter: Add counter->id to the throttle event
perf_counter: Better align code
perf_counter: Rename L2 to LL cache
perf_counter: Standardize event names
perf_counter: Rename enums
perf_counter tools: Clean up u64 usage
perf_counter: Rename perf_counter_limit sysctl
perf_counter: More paranoia settings
perf_counter: powerpc: Implement generalized cache events for POWER processors
perf_counters: powerpc: Add support for POWER7 processors
perf_counter: Accurate period data
perf_counter: Introduce struct for sample data
perf_counter tools: Normalize data using per sample period data
perf_counter: Annotate exit ctx recursion
perf_counter tools: Propagate signals properly
perf_counter tools: Small frequency related fixes
perf_counter: More aggressive frequency adjustment
perf_counter/x86: Fix the model number of Intel Core2 processors
perf_counter, x86: Correct some event and umask values for Intel processors
...
* 'topic/slab/earlyboot' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6:
vgacon: use slab allocator instead of the bootmem allocator
irq: use kcalloc() instead of the bootmem allocator
sched: use slab in cpupri_init()
sched: use alloc_cpumask_var() instead of alloc_bootmem_cpumask_var()
memcg: don't use bootmem allocator in setup code
irq/cpumask: make memoryless node zero happy
x86: remove some alloc_bootmem_cpumask_var calling
vt: use kzalloc() instead of the bootmem allocator
sched: use kzalloc() instead of the bootmem allocator
init: introduce mm_init()
vmalloc: use kzalloc() instead of alloc_bootmem()
slab: setup allocators earlier in the boot sequence
bootmem: fix slab fallback on numa
bootmem: use slab if bootmem is no longer available
slow_work_thread() sleeps on slow_work_thread_wq without WQ_FLAG_EXCLUSIVE,
this means that slow_work_enqueue()->__wake_up(nr_exclusive => 1) wakes up all
kslowd threads. This is not what we want, so we change slow_work_thread() to
use prepare_to_wait_exclusive() instead.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-2.6.31' of git://git.kernel.dk/linux-2.6-block: (153 commits)
block: add request clone interface (v2)
floppy: fix hibernation
ramdisk: remove long-deprecated "ramdisk=" boot-time parameter
fs/bio.c: add missing __user annotation
block: prevent possible io_context->refcount overflow
Add serial number support for virtio_blk, V4a
block: Add missing bounce_pfn stacking and fix comments
Revert "block: Fix bounce limit setting in DM"
cciss: decode unit attention in SCSI error handling code
cciss: Remove no longer needed sendcmd reject processing code
cciss: change SCSI error handling routines to work with interrupts enabled.
cciss: separate error processing and command retrying code in sendcmd_withirq_core()
cciss: factor out fix target status processing code from sendcmd functions
cciss: simplify interface of sendcmd() and sendcmd_withirq()
cciss: factor out core of sendcmd_withirq() for use by SCSI error handling code
cciss: Use schedule_timeout_uninterruptible in SCSI error handling code
block: needs to set the residual length of a bidi request
Revert "block: implement blkdev_readpages"
block: Fix bounce limit setting in DM
Removed reference to non-existing file Documentation/PCI/PCI-DMA-mapping.txt
...
Manually fix conflicts with tracing updates in:
block/blk-sysfs.c
drivers/ide/ide-atapi.c
drivers/ide/ide-cd.c
drivers/ide/ide-floppy.c
drivers/ide/ide-tape.c
include/trace/events/block.h
kernel/trace/blktrace.c
Lets not use the bootmem allocator in cpupri_init() as slab is already up when
it is run.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Slab is initialized when sched_init() runs now so lets use alloc_cpumask_var().
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Don't hardcode to node zero for early boot IRQ setup memory allocations.
[ penberg@cs.helsinki.fi: minor cleanups ]
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Now that we set up the slab allocator earlier, we can get rid of some
alloc_bootmem_cpumask_var() calls in boot code.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Now that kmem_cache_init() happens before sched_init(), we should use kzalloc()
and not the bootmem allocator.
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
This patch handles the kmemleak operations needed for modules loading so
that memory allocations from inside a module are properly tracked.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
So as to be able to distuinguish between multiple counters.
Signed-off-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>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Pure renames only, to PERF_COUNT_HW_* and PERF_COUNT_SW_*.
Signed-off-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>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Rename the perf enums to be in the 'perf_' namespace and strictly
enumerate the ABI bits.
Signed-off-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>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Rename perf_counter_limit to perf_counter_max_sample_rate and
prohibit creation of counters with a known higher sample
frequency.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
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>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Rename the perf_counter_priv knob to perf_counter_paranoia (because
priv can be read as private, as opposed to privileged) and provide
one more level:
0 - permissive
1 - restrict cpu counters to privilidged contexts
2 - restrict kernel-mode code counting and profiling
Signed-off-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>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'tracing-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
function-graph: always initialize task ret_stack
function-graph: move initialization of new tasks up in fork
function-graph: add memory barriers for accessing task's ret_stack
function-graph: enable the stack after initialization of other variables
function-graph: only allocate init tasks if it was not already done
Manually fix trivial conflict in kernel/trace/ftrace.c
* 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (244 commits)
Revert "x86, bts: reenable ptrace branch trace support"
tracing: do not translate event helper macros in print format
ftrace/documentation: fix typo in function grapher name
tracing/events: convert block trace points to TRACE_EVENT(), fix !CONFIG_BLOCK
tracing: add protection around module events unload
tracing: add trace_seq_vprint interface
tracing: fix the block trace points print size
tracing/events: convert block trace points to TRACE_EVENT()
ring-buffer: fix ret in rb_add_time_stamp
ring-buffer: pass in lockdep class key for reader_lock
tracing: add annotation to what type of stack trace is recorded
tracing: fix multiple use of __print_flags and __print_symbolic
tracing/events: fix output format of user stack
tracing/events: fix output format of kernel stack
tracing/trace_stack: fix the number of entries in the header
ring-buffer: discard timestamps that are at the start of the buffer
ring-buffer: try to discard unneeded timestamps
ring-buffer: fix bug in ring_buffer_discard_commit
ftrace: do not profile functions when disabled
tracing: make trace pipe recognize latency format flag
...
* 'rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
rcu: rcu_sched_grace_period(): kill the bogus flush_signals()
rculist: use list_entry_rcu in places where it's appropriate
rculist.h: introduce list_entry_rcu() and list_first_entry_rcu()
rcu: Update RCU tracing documentation for __rcu_pending
rcu: Add __rcu_pending tracing to hierarchical RCU
RCU: make treercu be default
We currently log hw.sample_period for PERF_SAMPLE_PERIOD, however this is
incorrect. When we adjust the period, it will only take effect the next
cycle but report it for the current cycle. So when we adjust the period
for every cycle, we're always wrong.
Solve this by keeping track of the last_period.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
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>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
For easy extension of the sample data, put it in a structure.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
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>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ever since Paul fixed it to unclone the context before taking the
ctx->lock this became a false positive, annotate it away.
Signed-off-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>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'futexes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
futex: fix restart in wait_requeue_pi
futex: fix restart for early wakeup in futex_wait_requeue_pi()
futex: cleanup error exit
futex: remove the wait queue
futex: add requeue-pi documentation
futex: remove FUTEX_REQUEUE_PI (non CMP)
futex: fix futex_wait_setup key handling
sparc64: extend TI_RESTART_BLOCK space by 8 bytes
futex: fixup unlocked requeue pi case
futex: add requeue_pi functionality
futex: split out futex value validation code
futex: distangle futex_requeue()
futex: add FUTEX_HAS_TIMEOUT flag to restart.futex.flags
rt_mutex: add proxy lock routines
futex: split out fixup owner logic from futex_lock_pi()
futex: split out atomic logic from futex_lock_pi()
futex: add helper to find the top prio waiter of a futex
futex: separate futex_wait_queue_me() logic from futex_wait()
* 'x86-xen-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (42 commits)
xen: cache cr0 value to avoid trap'n'emulate for read_cr0
xen/x86-64: clean up warnings about IST-using traps
xen/x86-64: fix breakpoints and hardware watchpoints
xen: reserve Xen start_info rather than e820 reserving
xen: add FIX_TEXT_POKE to fixmap
lguest: update lazy mmu changes to match lguest's use of kvm hypercalls
xen: honour VCPU availability on boot
xen: add "capabilities" file
xen: drop kexec bits from /sys/hypervisor since kexec isn't implemented yet
xen/sys/hypervisor: change writable_pt to features
xen: add /sys/hypervisor support
xen/xenbus: export xenbus_dev_changed
xen: use device model for suspending xenbus devices
xen: remove suspend_cancel hook
xen/dev-evtchn: clean up locking in evtchn
xen: export ioctl headers to userspace
xen: add /dev/xen/evtchn driver
xen: add irq_from_evtchn
xen: clean up gate trap/interrupt constants
xen: set _PAGE_NX in __supported_pte_mask before pagetable construction
...
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
sched: fix typo in sched-rt-group.txt file
ftrace: fix typo about map of kernel priority in ftrace.txt file.
sched: properly define the sched_group::cpumask and sched_domain::span fields
sched, timers: cleanup avenrun users
sched, timers: move calc_load() to scheduler
sched: Don't export sched_mc_power_savings on multi-socket single core system
sched: emit thread info flags with stack trace
sched: rt: document the risk of small values in the bandwidth settings
sched: Replace first_cpu() with cpumask_first() in ILB nomination code
sched: remove extra call overhead for schedule()
sched: use group_first_cpu() instead of cpumask_first(sched_group_cpus())
wait: don't use __wake_up_common()
sched: Nominate a power-efficient ilb in select_nohz_balancer()
sched: Nominate idle load balancer from a semi-idle package.
sched: remove redundant hierarchy walk in check_preempt_wakeup
* 'x86-kbuild-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (46 commits)
x86, boot: add new generated files to the appropriate .gitignore files
x86, boot: correct the calculation of ZO_INIT_SIZE
x86-64: align __PHYSICAL_START, remove __KERNEL_ALIGN
x86, boot: correct sanity checks in boot/compressed/misc.c
x86: add extension fields for bootloader type and version
x86, defconfig: update kernel position parameters
x86, defconfig: update to current, no material changes
x86: make CONFIG_RELOCATABLE the default
x86: default CONFIG_PHYSICAL_START and CONFIG_PHYSICAL_ALIGN to 16 MB
x86: document new bzImage fields
x86, boot: make kernel_alignment adjustable; new bzImage fields
x86, boot: remove dead code from boot/compressed/head_*.S
x86, boot: use LOAD_PHYSICAL_ADDR on 64 bits
x86, boot: make symbols from the main vmlinux available
x86, boot: determine compressed code offset at compile time
x86, boot: use appropriate rep string for move and clear
x86, boot: zero EFLAGS on 32 bits
x86, boot: set up the decompression stack as early as possible
x86, boot: straighten out ranges to copy/zero in compressed/head*.S
x86, boot: stylistic cleanups for boot/compressed/head_64.S
...
Fixed trivial conflict in arch/x86/configs/x86_64_defconfig manually
* 'irq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (76 commits)
x86, apic: Fix dummy apic read operation together with broken MP handling
x86, apic: Restore irqs on fail paths
x86: Print real IOAPIC version for x86-64
x86: enable_update_mptable should be a macro
sparseirq: Allow early irq_desc allocation
x86, io-apic: Don't mark pin_programmed early
x86, irq: don't call mp_config_acpi_gsi() if update_mptable is not enabled
x86, irq: update_mptable needs pci_routeirq
x86: don't call read_apic_id if !cpu_has_apic
x86, apic: introduce io_apic_irq_attr
x86/pci: add 4 more return parameters to IO_APIC_get_PCI_irq_vector(), fix
x86: read apic ID in the !acpi_lapic case
x86: apic: Fixmap apic address even if apic disabled
x86: display extended apic registers with print_local_APIC and cpu_debug code
x86: read apic ID in the !acpi_lapic case
x86: clean up and fix setup_clear/force_cpu_cap handling
x86: apic: Check rev 3 fadt correctly for physical_apic bit
x86/pci: update pirq_enable_irq() to setup io apic routing
x86/acpi: move setup io apic routing out of CONFIG_ACPI scope
x86/pci: add 4 more return parameters to IO_APIC_get_PCI_irq_vector()
...
Also employ the overflow handler to adjust the frequency, this results
in a stable frequency in about 40~50 samples, instead of that many ticks.
This also means we can start sampling at a sample period of 1 without
running head-first into the throttle.
It relies on sched_clock() to accurately measure the time difference
between the overflow NMIs.
Signed-off-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>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
When reading the trace buffer, there is a race that when a module
is unloaded it removes events that is stilled referenced in the buffers.
This patch adds the protection around the unloading of the events
from modules and the reading of the trace buffers.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The code to update the print formats for events requires a vprintf
format in the trace_seq. This patch adds that interface.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
TRACE_EVENT is a more generic way to define tracepoints. Doing so adds
these new capabilities to this tracepoint:
- zero-copy and per-cpu splice() tracing
- binary tracing without printf overhead
- structured logging records exposed under /debug/tracing/events
- trace events embedded in function tracer output and other plugins
- user-defined, per tracepoint filter expressions
...
Cons:
- no dev_t info for the output of plug, unplug_timer and unplug_io events.
no dev_t info for getrq and sleeprq events if bio == NULL.
no dev_t info for rq_abort,...,rq_requeue events if rq->rq_disk == NULL.
This is mainly because we can't get the deivce from a request queue.
But this may change in the future.
- A packet command is converted to a string in TP_assign, not TP_print.
While blktrace do the convertion just before output.
Since pc requests should be rather rare, this is not a big issue.
- In blktrace, an event can have 2 different print formats, but a TRACE_EVENT
has a unique format, which means we have some unused data in a trace entry.
The overhead is minimized by using __dynamic_array() instead of __array().
I've benchmarked the ioctl blktrace vs the splice based TRACE_EVENT tracing:
dd dd + ioctl blktrace dd + TRACE_EVENT (splice)
1 7.36s, 42.7 MB/s 7.50s, 42.0 MB/s 7.41s, 42.5 MB/s
2 7.43s, 42.3 MB/s 7.48s, 42.1 MB/s 7.43s, 42.4 MB/s
3 7.38s, 42.6 MB/s 7.45s, 42.2 MB/s 7.41s, 42.5 MB/s
So the overhead of tracing is very small, and no regression when using
those trace events vs blktrace.
And the binary output of TRACE_EVENT is much smaller than blktrace:
# ls -l -h
-rw-r--r-- 1 root root 8.8M 06-09 13:24 sda.blktrace.0
-rw-r--r-- 1 root root 195K 06-09 13:24 sda.blktrace.1
-rw-r--r-- 1 root root 2.7M 06-09 13:25 trace_splice.out
Following are some comparisons between TRACE_EVENT and blktrace:
plug:
kjournald-480 [000] 303.084981: block_plug: [kjournald]
kjournald-480 [000] 303.084981: 8,0 P N [kjournald]
unplug_io:
kblockd/0-118 [000] 300.052973: block_unplug_io: [kblockd/0] 1
kblockd/0-118 [000] 300.052974: 8,0 U N [kblockd/0] 1
remap:
kjournald-480 [000] 303.085042: block_remap: 8,0 W 102736992 + 8 <- (8,8) 33384
kjournald-480 [000] 303.085043: 8,0 A W 102736992 + 8 <- (8,8) 33384
bio_backmerge:
kjournald-480 [000] 303.085086: block_bio_backmerge: 8,0 W 102737032 + 8 [kjournald]
kjournald-480 [000] 303.085086: 8,0 M W 102737032 + 8 [kjournald]
getrq:
kjournald-480 [000] 303.084974: block_getrq: 8,0 W 102736984 + 8 [kjournald]
kjournald-480 [000] 303.084975: 8,0 G W 102736984 + 8 [kjournald]
bash-2066 [001] 1072.953770: 8,0 G N [bash]
bash-2066 [001] 1072.953773: block_getrq: 0,0 N 0 + 0 [bash]
rq_complete:
konsole-2065 [001] 300.053184: block_rq_complete: 8,0 W () 103669040 + 16 [0]
konsole-2065 [001] 300.053191: 8,0 C W 103669040 + 16 [0]
ksoftirqd/1-7 [001] 1072.953811: 8,0 C N (5a 00 08 00 00 00 00 00 24 00) [0]
ksoftirqd/1-7 [001] 1072.953813: block_rq_complete: 0,0 N (5a 00 08 00 00 00 00 00 24 00) 0 + 0 [0]
rq_insert:
kjournald-480 [000] 303.084985: block_rq_insert: 8,0 W 0 () 102736984 + 8 [kjournald]
kjournald-480 [000] 303.084986: 8,0 I W 102736984 + 8 [kjournald]
Changelog from v2 -> v3:
- use the newly introduced __dynamic_array().
Changelog from v1 -> v2:
- use __string() instead of __array() to minimize the memory required
to store hex dump of rq->cmd().
- support large pc requests.
- add missing blk_fill_rwbs_rq() in block_rq_requeue TRACE_EVENT.
- some cleanups.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4A2DF669.5070905@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The update of ret got mistakenly added to the if statement of
rb_try_to_discard. The variable ret should be 1 on commit and zero
otherwise.
[ Impact: fix compiler warning and real bug ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
These are defined as static cpumask_var_t so if MAXSMP is not used,
they are cleared already. Avoid surprises when MAXSMP is enabled.
Signed-off-by: Yinghai Lu <yinghai.lu@kernel.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>