Commit Graph

3685 Commits

Author SHA1 Message Date
Linus Torvalds
6671de344c Merge branch 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (26 commits)
  posix timers: fix RLIMIT_CPU && fork()
  time: ntp: fix bug in ntp_update_offset() & do_adjtimex(), fix
  time: ntp: clean up second_overflow()
  time: ntp: simplify ntp_tick_adj calculations
  time: ntp: make 64-bit constants more robust
  time: ntp: refactor do_adjtimex() some more
  time: ntp: refactor do_adjtimex()
  time: ntp: fix bug in ntp_update_offset() & do_adjtimex()
  time: ntp: micro-optimize ntp_update_offset()
  time: ntp: simplify ntp_update_offset_fll()
  time: ntp: refactor and clean up ntp_update_offset()
  time: ntp: refactor up ntp_update_frequency()
  time: ntp: clean up ntp_update_frequency()
  time: ntp: simplify the MAX_TICKADJ_SCALED definition
  time: ntp: simplify the second_overflow() code flow
  time: ntp: clean up kernel/time/ntp.c
  x86: hpet: stop HPET_COUNTER when programming periodic mode
  x86: hpet: provide separate functions to stop and start the counter
  x86: hpet: print HPET registers during setup (if hpet=verbose is used)
  time: apply NTP frequency/tick changes immediately
  ...
2009-03-26 16:05:42 -07:00
Linus Torvalds
831576fe40 Merge branch 'sched-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (46 commits)
  sched: Add comments to find_busiest_group() function
  sched: Refactor the power savings balance code
  sched: Optimize the !power_savings_balance during fbg()
  sched: Create a helper function to calculate imbalance
  sched: Create helper to calculate small_imbalance in fbg()
  sched: Create a helper function to calculate sched_domain stats for fbg()
  sched: Define structure to store the sched_domain statistics for fbg()
  sched: Create a helper function to calculate sched_group stats for fbg()
  sched: Define structure to store the sched_group statistics for fbg()
  sched: Fix indentations in find_busiest_group() using gotos
  sched: Simple helper functions for find_busiest_group()
  sched: remove unused fields from struct rq
  sched: jiffies not printed per CPU
  sched: small optimisation of can_migrate_task()
  sched: fix typos in documentation
  sched: add avg_overlap decay
  x86, sched_clock(): mark variables read-mostly
  sched: optimize ttwu vs group scheduling
  sched: TIF_NEED_RESCHED -> need_reshed() cleanup
  sched: don't rebalance if attached on NULL domain
  ...
2009-03-26 16:05:01 -07:00
Linus Torvalds
ada19a31a9 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq: (35 commits)
  [CPUFREQ] Prevent p4-clockmod from auto-binding to the ondemand governor.
  [CPUFREQ] Make cpufreq-nforce2 less obnoxious
  [CPUFREQ] p4-clockmod reports wrong frequency.
  [CPUFREQ] powernow-k8: Use a common exit path.
  [CPUFREQ] Change link order of x86 cpufreq modules
  [CPUFREQ] conservative: remove 10x from def_sampling_rate
  [CPUFREQ] conservative: fixup governor to function more like ondemand logic
  [CPUFREQ] conservative: fix dbs_cpufreq_notifier so freq is not locked
  [CPUFREQ] conservative: amend author's email address
  [CPUFREQ] Use swap() in longhaul.c
  [CPUFREQ] checkpatch cleanups for acpi-cpufreq
  [CPUFREQ] powernow-k8: Only print error message once, not per core.
  [CPUFREQ] ondemand/conservative: sanitize sampling_rate restrictions
  [CPUFREQ] ondemand/conservative: deprecate sampling_rate{min,max}
  [CPUFREQ] powernow-k8: Always compile powernow-k8 driver with ACPI support
  [CPUFREQ] Introduce /sys/devices/system/cpu/cpu*/cpufreq/cpuinfo_transition_latency
  [CPUFREQ] checkpatch cleanups for powernow-k8
  [CPUFREQ] checkpatch cleanups for ondemand governor.
  [CPUFREQ] checkpatch cleanups for powernow-k7
  [CPUFREQ] checkpatch cleanups for speedstep related drivers.
  ...
2009-03-26 11:04:08 -07:00
Ingo Molnar
e8684605ad Merge branch 'timers/hpet' into timers/core 2009-03-26 15:45:45 +01:00
Ingo Molnar
a5ebc0b1a7 Merge commit 'v2.6.29' into timers/core 2009-03-26 15:45:22 +01:00
Ingo Molnar
37ba317c9e Merge branches 'sched/cleanups' and 'linus' into sched/core 2009-03-18 09:57:02 +01:00
Masami Hiramatsu
30390880de prevent boosting kprobes on exception address
Don't boost at the addresses which are listed on exception tables,
because major page fault will occur on those addresses.  In that case,
kprobes can not ensure that when instruction buffer can be freed since
some processes will sleep on the buffer.

kprobes-ia64 already has same check.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-17 09:11:48 -07:00
Linus Torvalds
9e8912e04e Fast TSC calibration: calculate proper frequency error bounds
In order for ntpd to correctly synchronize the clocks, the frequency of
the system clock must not be off by more than 500 ppm (or, put another
way, 1:2000), or ntpd will end up giving up on trying to synchronize
properly, and ends up reseting the clock in jumps instead.

The fast TSC PIT calibration sometimes failed this test - it was
assuming that the PIT reads always took about one microsecond each (2us
for the two reads to get a 16-bit timer), and that calibrating TSC to
the PIT over 15ms should thus be sufficient to get much closer than
500ppm (max 2us error on both sides giving 4us over 15ms: a 270 ppm
error value).

However, that assumption does not always hold: apparently some hardware
is either very much slower at reading the PIT registers, or there was
other noise causing at least one machine to get 700+ ppm errors.

So instead of using a fixed 15ms timing loop, this changes the fast PIT
calibration to read the TSC delta over the individual PIT timer reads,
and use the result to calculate the error bars on the PIT read timing
properly.  We then successfully calibrate the TSC only if the maximum
error bars fall below 500ppm.

In the process, we also relax the timing to allow up to 25ms for the
calibration, although it can happen much faster depending on hardware.

Reported-and-tested-by: Jesper Krogh <jesper@krogh.cc>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-17 08:13:17 -07:00
Linus Torvalds
a6a80e1d8c Fix potential fast PIT TSC calibration startup glitch
During bootup, when we reprogram the PIT (programmable interval timer)
to start counting down from 0xffff in order to use it for the fast TSC
calibration, we should also make sure to delay a bit afterwards to allow
the PIT hardware to actually start counting with the new value.

That will happens at the next CLK pulse (1.193182 MHz), so the easiest
way to do that is to just wait at least one microsecond after
programming the new PIT counter value.  We do that by just reading the
counter value back once - which will take about 2us on PC hardware.

Reported-and-tested-by: john stultz <johnstul@us.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-17 07:58:26 -07:00
Ingo Molnar
f6411fe7e0 Merge branches 'sched/clock', 'sched/urgent' and 'linus' into sched/core 2009-03-13 04:50:44 +01:00
Ingo Molnar
f24ade3a33 x86, sched_clock(): mark variables read-mostly
Impact: micro-optimization

There's a number of variables in the sched_clock() path that are
in .data/.bss - but not marked __read_mostly. This creates the
danger of accidental false cacheline sharing with some other,
write-often variable.

So mark them __read_mostly.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-10 19:02:30 +01:00
Ingo Molnar
8c54436ae9 Merge branches 'sched/cleanups' and 'linus' into sched/core 2009-03-10 16:34:43 +01:00
Linus Torvalds
99adcd9d67 Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq:
  [CPUFREQ] Add p4-clockmod sysfs-ui removal to feature-removal schedule.
  Revert "[CPUFREQ] Disable sysfs ui for p4-clockmod."
2009-03-09 13:23:59 -07:00
Dave Jones
129f8ae9b1 Revert "[CPUFREQ] Disable sysfs ui for p4-clockmod."
This reverts commit e088e4c9cd.

Removing the sysfs interface for p4-clockmod was flagged as a
regression in bug 12826.

Course of action:
 - Find out the remaining causes of overheating, and fix them
   if possible. ACPI should be doing the right thing automatically.
   If it isn't, we need to fix that.
 - mark p4-clockmod ui as deprecated
 - try again with the removal in six months.

It's not really feasible to printk about the deprecation, because
it needs to happen at all the sysfs entry points, which means adding
a lot of strcmp("p4-clockmod".. calls to the core, which.. bleuch.

Signed-off-by: Dave Jones <davej@redhat.com>
2009-03-09 15:07:33 -04:00
Markus Metzger
73bf1b62f5 x86, pebs: correct qualifier passed to ds_write_config() from ds_request_pebs()
ds_write_config() can write the BTS as well as the PEBS part of
the DS config. ds_request_pebs() passes the wrong qualifier, which
results in the wrong configuration to be written.

Reported-by: Stephane Eranian <eranian@googlemail.com>
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
LKML-Reference: <20090305085721.A22550@sedona.ch.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-06 16:13:15 +01:00
Markus Metzger
9ca0791dca x86, bts: remove bad warning
In case a ptraced task is reaped (while the tracer is still attached),
ds_exit_thread() is called before ptrace_exit(). The latter will
release the bts_tracer and remove the thread's ds_ctx.
The former will WARN() if the context is not NULL.

Oleg Nesterov submitted patches that move ptrace_exit() before
exit_thread() and thus reverse the order of the above calls.

Remove the bad warning. I will add it again when Oleg's changes are in.

Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
LKML-Reference: <20090305084954.A22000@sedona.ch.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-06 16:13:15 +01:00
Ingo Molnar
49d2d266ad Merge commit 'v2.6.29-rc7' into sched/core 2009-03-05 11:59:10 +01:00
Dave Jones
36e8abf3ed [CPUFREQ] Prevent p4-clockmod from auto-binding to the ondemand governor.
The latency of p4-clockmod sucks so hard that scaling on a regular
basis with ondemand is a really bad idea.

Signed-off-by: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Dave Jones <davej@redhat.com>
2009-03-05 00:16:26 -05:00
Leann Ogasawara
dd4124a8a0 x86: add Dell XPS710 reboot quirk
Dell XPS710 will hang on reboot.  This is resolved by adding a quirk to
set bios reboot.

Signed-off-by: Leann Ogasawara <leann.ogasawara@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Cc: "manoj.iyer" <manoj.iyer@canonical.com>
Cc: <stable@kernel.org>
LKML-Reference: <1236196380.3231.89.camel@emiko>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-04 20:56:15 +01:00
Daniel Glöckner
ab9e18587f x86, math-emu: fix init_fpu for task != current
Impact: fix math-emu related crash while using GDB/ptrace

init_fpu() calls finit to initialize a task's xstate, while finit always
works on the current task. If we use PTRACE_GETFPREGS on another
process and both processes did not already use floating point, we get
a null pointer exception in finit.

This patch creates a new function finit_task that takes a task_struct
parameter. finit becomes a wrapper that simply calls finit_task with
current. On the plus side this avoids many calls to get_current which
would each resolve to an inline assembler mov instruction.

An empty finit_task has been added to i387.h to avoid linker errors in
case the compiler still emits the call in init_fpu when
CONFIG_MATH_EMULATION is not defined.

The declaration of finit in i387.h has been removed as the remaining
code using this function gets its prototype from fpu_proto.h.

Signed-off-by: Daniel Glöckner <dg@emlix.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: "Pallipadi Venkatesh" <venkatesh.pallipadi@intel.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Bill Metzenthen <billm@melbpc.org.au>
LKML-Reference: <E1Lew31-0004il-Fg@mailer.emlix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-04 20:33:16 +01:00
Huang Ying
dd39ecf522 x86: EFI: Back efi_ioremap with init_memory_mapping instead of FIX_MAP
Impact: Fix boot failure on EFI system with large runtime memory range

Brian Maly reported that some EFI system with large runtime memory
range can not boot. Because the FIX_MAP used to map runtime memory
range is smaller than run time memory range.

This patch fixes this issue by re-implement efi_ioremap() with
init_memory_mapping().

Reported-and-tested-by: Brian Maly <bmaly@redhat.com>
Signed-off-by: Huang Ying <ying.huang@intel.com>
Cc: Brian Maly <bmaly@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1236135513.6204.306.camel@yhuang-dev.sh.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-04 19:20:16 +01:00
Brian Maly
ff0c087490 x86: fix DMI on EFI
Impact: reactivate DMI quirks on EFI hardware

DMI tables are loaded by EFI, so the dmi calls must happen after
efi_init() and not before.

Currently Apple hardware uses DMI to determine the framebuffer mappings
for efifb. Without DMI working you also have no video on MacBook Pro.

This patch resolves the DMI issue for EFI hardware (DMI is now properly
detected at boot), and additionally efifb now loads on Apple hardware
(i.e. video works).

Signed-off-by: Brian Maly <bmaly@redhat>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Cc: ying.huang@intel.com
LKML-Reference: <49ADEDA3.1030406@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

 arch/x86/kernel/setup.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)
2009-03-04 18:55:56 +01:00
Roland McGrath
ccbe495caa x86-64: syscall-audit: fix 32/64 syscall hole
On x86-64, a 32-bit process (TIF_IA32) can switch to 64-bit mode with
ljmp, and then use the "syscall" instruction to make a 64-bit system
call.  A 64-bit process make a 32-bit system call with int $0x80.

In both these cases, audit_syscall_entry() will use the wrong system
call number table and the wrong system call argument registers.  This
could be used to circumvent a syscall audit configuration that filters
based on the syscall numbers or argument details.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-02 15:41:30 -08:00
Ingo Molnar
83ce400928 x86: set X86_FEATURE_TSC_RELIABLE
If the TSC is constant and non-stop, also set it reliable.

(We will turn this off in DMI quirks for multi-chassis systems)

The performance number on a 16-way Nehalem system running
32 tasks that context-switch between each other is significant:

   sched_clock_stable=0		sched_clock_stable=1
   ....................         ....................
   22.456925 million/sec        24.306972 million/sec   [+8.2%]

lmbench's "lat_ctx -s 0 2" goes from 0.63 microseconds to
0.59 microseconds - a 6.7% increase in context-switching
performance.

Perfstat of 1 million pipe context switches between two tasks:

 Performance counter stats for './pipe-test-1m':

       [before]           [after]
   ............      ............
   37621.421089      36436.848378    task clock ticks     (msecs)

              0                 0    CPU migrations       (events)
        2000274           2000189    context switches     (events)
            194               193    pagefaults           (events)
     8433799643        8171016416    CPU cycles           (events) -3.21%
     8370133368        8180999694    instructions         (events) -2.31%
        4158565           3895941    cache references     (events) -6.74%
          44312             46264    cache misses         (events)

    2349.287976       2279.362465    wall-time            (msecs)  -3.06%

The speedup comes straight from the reduction in the instruction
count. sched_clock_cpu() got simpler and the whole workload thus
executes faster.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-26 21:20:25 +01:00
Matthew Garrett
eb3092cee7 [CPUFREQ] Make cpufreq-nforce2 less obnoxious
Not owning an nforce2 is a sign of good taste, not an error.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:32 -05:00
Matthias-Christian Ott
199785eac8 [CPUFREQ] p4-clockmod reports wrong frequency.
http://bugzilla.kernel.org/show_bug.cgi?id=10968

[ Updated for current tree, and fixed compile failure
  when p4-clockmod was built modular -- davej]

From: Matthias-Christian Ott <ott@mirix.org>
Signed-off-by: Dominik Brodowski <linux@brodo.de>
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:32 -05:00
Dave Jones
0cb8bc2560 [CPUFREQ] powernow-k8: Use a common exit path.
a0abd520fd introduced a slew of
extra kfree/return -ENODEV pairs. This replaces them all
with gotos.

Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:32 -05:00
Matthew Garrett
de3ed81d74 [CPUFREQ] Change link order of x86 cpufreq modules
Change the link order of the cpufreq modules to ensure that they're
probed in the preferred order when statically linked in.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:32 -05:00
Dave Jones
91420220d2 [CPUFREQ] Use swap() in longhaul.c
Remove hand-coded implementation of swap()

Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:31 -05:00
Dave Jones
3a58df35a6 [CPUFREQ] checkpatch cleanups for acpi-cpufreq
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:31 -05:00
Thomas Renninger
79cc56af9f [CPUFREQ] powernow-k8: Only print error message once, not per core.
This is the typical message you get if you plug in a CPU
which is newer than your BIOS. It's annoying seeing this
message for each core.

Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:31 -05:00
Thomas Renninger
57f4fa6991 [CPUFREQ] powernow-k8: Always compile powernow-k8 driver with ACPI support
powernow-k8 driver should always try to get cpufreq info from ACPI.
Otherwise it will not be able to detect the transition latency correctly
which results in ondemand governor taking a wrong sampling rate which will
then result in sever performance loss.

Let the user not shoot himself in the foot and always compile in ACPI
support for powernow-k8.

This also fixes a wrong message if ACPI_PROCESSOR is compiled as a module and
#ifndef CONFIG_ACPI_PROCESSOR
path is chosen.

Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:31 -05:00
Dave Jones
0e64a0c982 [CPUFREQ] checkpatch cleanups for powernow-k8
This driver has so many long function names, and deep nested if's
The remaining warnings will need some code restructuring to clean up.

Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:30 -05:00
Dave Jones
b9e7638a30 [CPUFREQ] checkpatch cleanups for powernow-k7
The asm/timer.h warning can be ignored, it's needed for
recalibrate_cpu_khz()

Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:30 -05:00
Dave Jones
bbfebd6655 [CPUFREQ] checkpatch cleanups for speedstep related drivers.
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:30 -05:00
Dave Jones
6072ace436 [CPUFREQ] checkpatch cleanups for sc520
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:29 -05:00
Dave Jones
14a6650f13 [CPUFREQ] checkpatch cleanups for powernow-k6
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:29 -05:00
Dave Jones
48ee923a66 [CPUFREQ] checkpatch cleanups for longrun
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:29 -05:00
Dave Jones
ac617bd0f7 [CPUFREQ] checkpatch cleanups for longhaul
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:29 -05:00
Dave Jones
00f6a235bf [CPUFREQ] checkpatch cleanups for gx-suspmod
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:29 -05:00
Dave Jones
c9b8c87152 [CPUFREQ] checkpatch cleanups for e_powersaver
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:28 -05:00
Dave Jones
04cd1a99dc [CPUFREQ] checkpatch cleanups for elanfreq
The remaining warning about the simple_strtoul conversion
to strict_strtoul seems kind of pointless to me.

Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:28 -05:00
Dave Jones
20174b65d9 [CPUFREQ] nforce2: Use driver prefix, not cpufreq prefix.
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:28 -05:00
Dave Jones
b5c9166662 [CPUFREQ] checkpatch cleanups for cpufreq-nforce2
Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:28 -05:00
Dave Jones
fff78ad5ce [CPUFREQ] Stupidly trivial CodingStyle fix
GNU indent complains about this being ambiguous, because it's dumb.
One of my automated tests relies on the output of indent, so this shuts
it up.

Signed-off-by: Dave Jones <davej@redhat.com>
2009-02-24 22:47:28 -05:00
Rafael J. Wysocki
770824bdc4 PM: Split up sysdev_[suspend|resume] from device_power_[down|up]
Move the sysdev_suspend/resume from the callee to the callers, with
no real change in semantics, so that we can rework the disabling of
interrupts during suspend/hibernation.

This is based on an earlier patch from Linus.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-22 10:33:44 -08:00
Linus Torvalds
936577c61d x86: Add IRQF_TIMER to legacy x86 timer interrupt descriptors
Right now nobody cares, but the suspend/resume code will eventually want
to suspend device interrupts without suspending the timer, and will
depend on this flag to know.

The modern x86 timer infrastructure uses the local APIC timers and never
shows up as a device interrupt at all, so it isn't affected and doesn't
need any of this.

Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-22 10:27:49 -08:00
Andreas Herrmann
c23e253e67 x86: hpet: stop HPET_COUNTER when programming periodic mode
Impact: fix system hang on some systems operating with HZ_1000

On a system that stalled with HZ_1000, the first value written to
T0_CMP (when the main counter was not stopped) did not trigger an
interrupt. Instead after the main counter wrapped around (after
several minutes) an interrupt was triggered and afterwards the
periodic interrupt took effect.

This can be fixed by implementing HPET spec recommendation for
programming the periodic mode (i.e. stopping the main counter).

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Mark Hounschell <markh@compro.net>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-22 18:01:18 +01:00
Andreas Herrmann
8d6f0c8214 x86: hpet: provide separate functions to stop and start the counter
By splitting up existing hpet_start_counter function.

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Mark Hounschell <markh@compro.net>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-22 18:01:17 +01:00
Andreas Herrmann
b98103a559 x86: hpet: print HPET registers during setup (if hpet=verbose is used)
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Mark Hounschell <markh@compro.net>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-22 18:01:14 +01:00