Commit graph

329 commits

Author SHA1 Message Date
Ingo Molnar
cb491fca55 x86, mce: Rename sysfs variables
Shorten variable names. This also compacts the code a bit.

	device_mce		=> mce_dev
	mce_device_initialized	=> mce_dev_initialized
	mce_attribute		=> mce_attrs

[ Impact: cleanup ]

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-28 09:24:11 -07:00
Ingo Molnar
dba3725d44 x86, mce: unify
move mce_64.c => mce.c and glue it up in the Makefile.
Remove mce_32.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-28 09:24:11 -07:00
Ingo Molnar
711c2e481c x86, mce: unify, prepare for 32-bit v2
Prepare the 64-bit mce_64.c code side to be built on 32-bit.

[ includes ifdef relocation by Andi Kleen ]

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Andi Kleen <ak@firstfloor.org>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-28 09:24:11 -07:00
Ingo Molnar
a988d334ae x86, mce: unify, prepare codes
Move current 32-bit mce_32.c code into mce_64.c.

[ Remove unused artifact stop/restart_mce pointed by Andi Kleen ]

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Andi Kleen <ak@firstfloor.org>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-28 09:24:11 -07:00
Thomas Gleixner
a65d086235 x86, mce: unify Intel thermal init
Mechanic unification. No change in code.

[ Impact: cleanup, 32-bit / 64-bit unification ]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-28 09:24:10 -07:00
Thomas Gleixner
6cc6f3ebd1 x86, mce: unify Intel thermal init, prepare
Prepare for unification, make two intel_init_thermal equal.

[ Impact: cleanup ]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-28 09:24:10 -07:00
Ingo Molnar
1cb2a8e176 x86, mce: clean up mce_amd_64.c
Make the coding style match that of the rest of the x86 arch code.

[ Impact: cleanup ]

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-28 09:24:10 -07:00
Ingo Molnar
cb6f3c155b x86, mce: clean up therm_throt.c
Make the coding style match that of the rest of the x86 arch code.

[ Impact: cleanup ]

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-28 09:24:10 -07:00
Ingo Molnar
bdbfbdd5e8 x86, mce: clean up non-fatal.c
Make the coding style match that of the rest of the x86 arch code.

[ Impact: cleanup ]

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-28 09:24:10 -07:00
Ingo Molnar
91425084f7 x86, mce: clean up winchip.c
Make the coding style match that of the rest of the x86 arch code.

[ Impact: cleanup ]

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-28 09:24:10 -07:00
Ingo Molnar
efee4ca809 x86, mce: clean up k7.c
Make the coding style match that of the rest of the x86 arch code.

[ Impact: cleanup ]

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-28 09:24:10 -07:00
Ingo Molnar
ea2566ff80 x86, mce: clean up p6.c
Make the coding style match that of the rest of the x86 arch code.

[ Impact: cleanup ]

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-28 09:24:09 -07:00
Ingo Molnar
ed8bc7ed9a x86, mce: clean up p5.c
Make the coding style match that of the rest of the x86 arch code.

[ Impact: cleanup ]

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-28 09:24:09 -07:00
Ingo Molnar
c5aaf0e070 x86, mce: clean up p4.c
Make the coding style match that of the rest of the x86 arch code.

[ Impact: cleanup ]

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-28 09:24:09 -07:00
Ingo Molnar
3b58dfd04b x86, mce: clean up mce_32.c
Make the coding style match that of the rest of the x86 arch code.

[ Impact: cleanup ]

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-28 09:24:09 -07:00
Ingo Molnar
e9eee03e99 x86, mce: clean up mce_64.c
This file has been modified many times along the years, by multiple
authors, so the general style and structure has diverged in a number
of areas making this file hard to read.

So fix the coding style match that of the rest of the x86 arch code.

[ Impact: cleanup ]

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-28 09:24:09 -07:00
Hidetoshi Seto
13503fa913 x86, mce: Cleanup param parser
- Fix the comment formatting.

- The error path does not return 0, and printk lacks level and "\n".

- Move __setup("nomce") next to mcheck_disable().

- Improve readability etc.

[ Impact: cleanup ]

Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
LKML-Reference: <49CB3F38.7090703@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-28 09:24:09 -07:00
Huang Weiyi
778dedae0c x86: mce: remove duplicated #include
Remove duplicated #include in arch/x86/kernel/cpu/mcheck/mce_intel_64.c.

[ Impact: cleanup ]

Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-09 07:06:26 +02:00
Hidetoshi Seto
e5299926d7 x86: MCE: make cmci_discover_lock irq-safe
Lockdep reports the warning below when Li tries to offline one cpu:

[  110.835487] =================================
[  110.835616] [ INFO: inconsistent lock state ]
[  110.835688] 2.6.30-rc4-00336-g8c9ed89 #52
[  110.835757] ---------------------------------
[  110.835828] inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage.
[  110.835908] swapper/0 [HC1[1]:SC0[0]:HE0:SE1] takes:
[  110.835982]  (cmci_discover_lock){?.+...}, at: [<ffffffff80236dc0>] cmci_clear+0x30/0x9b

cmci_clear() can be called via smp_call_function_single().

It is better to disable interrupt while holding cmci_discover_lock,
to turn it into an irq-safe lock - we can deadlock otherwise.

[ Impact: fix possible deadlock in the MCE code ]

Reported-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4A03ED38.8000700@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reported-by: Shaohua Li<shaohua.li@intel.com>
2009-05-08 11:03:26 +02:00
Andi Kleen
5679af4c16 x86, mce: fix boot logging logic
The earlier patch to change the poller to a separate function subtly
broke the boot logging logic. This could lead to machine checks
getting logged at boot even when disabled or defaulting to off
on some systems. Fix that.

[ Impact: bug fix - avoid spurious MCE in log ]

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-04-22 13:56:25 -07:00
Andi Kleen
6298c512bc x86, mce: make polling timer interval per CPU
The polling timer while running per CPU still uses a global next_interval
variable, which lead to some CPUs either polling too fast or too slow.   
This was not a serious problem because all errors get picked up eventually,
but it's still better to avoid it. Turn next_interval into a per cpu variable.

v2: Fix check_interval == 0 case (Hidetoshi Seto)

[ Impact: minor bug fix ]

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-04-22 13:54:37 -07:00
Ingo Molnar
65fb0d23fc Merge branch 'linus' into cpumask-for-linus
Conflicts:
	arch/x86/kernel/cpu/common.c
2009-03-30 23:53:32 +02:00
Andrew Morton
a6b6a14e0c x86: use smp_call_function_single() in arch/x86/kernel/cpu/mcheck/mce_amd_64.c
Attempting to rid us of the problematic work_on_cpu().  Just use
smp_call_function_single() here.

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
LKML-Reference: <20090318042217.EF3F1DDF39@ozlabs.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-18 07:03:12 +01:00
Hidetoshi Seto
514ec49a5f x86, mce: remove incorrect __cpuinit for intel_init_cmci()
Impact: Bug fix on UP

Referring commit cc3ca22063,
Peter removed __cpuinit annotations for mce_cpu_features()
and its successor functions, which caused troubles on UP
configurations.

However the intel_init_cmci() was introduced after that and
it also has __cpuinit annotation even though it is called from
mce_cpu_features(). Remove the annotation from that function
too.

Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-16 09:15:32 +01:00
Rusty Russell
4f0628963c cpumask: use new cpumask functions throughout x86
Impact: cleanup

1) &cpu_online_map -> cpu_online_mask
2) first_cpu/next_cpu_nr -> cpumask_first/cpumask_next
3) cpu_*_map manipulation -> init_cpu_* / set_cpu_*

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-03-13 14:49:54 +10:30
Rusty Russell
996867d096 cpumask: convert arch/x86/kernel/cpu/mcheck/mce_64.c
Impact: reduce kernel memory usage when CONFIG_CPUMASK_OFFSTACK=y

Simple conversion of mce_device_initialized to cpumask_var_t.  We don't
check the alloc_cpumask_var() return since it's boot-time only, and
the misc_register() in that same function isn't checked.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-03-13 14:49:51 +10:30
Rusty Russell
7ad728f981 cpumask: x86: convert cpu_sibling_map/cpu_core_map to cpumask_var_t
Impact: reduce per-cpu size for CONFIG_CPUMASK_OFFSTACK=y

In most places it's cleaner to use the accessors cpu_sibling_mask()
and cpu_core_mask() wrappers which already exist.

I couldn't avoid cleaning up the access in oprofile, either.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-03-13 14:49:50 +10:30
KOSAKI Motohiro
5490fa9673 x86, mce: use round_jiffies() instead round_jiffies_relative()
Impact: saving power _very_ little

round_jiffies() round up absolute jiffies to full second.
round_jiffies_relative() round up relative jiffies to full second.

The "t->expires" is absolute jiffies. Then, round_jiffies() should be
used instead round_jiffies_relative().

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-03-10 22:33:06 -07:00
Ingo Molnar
73af76dfd1 x86, mce: fix build failure in arch/x86/kernel/cpu/mcheck/threshold.c
Impact: build fix

The APIC code rewrite in the x86 tree broke the x86/mce branch:

 arch/x86/kernel/cpu/mcheck/threshold.c: In function ‘mce_threshold_interrupt’:
 arch/x86/kernel/cpu/mcheck/threshold.c:24: error: implicit declaration of function ‘ack_APIC_irq’

Also tidy up the file a bit while at it.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-04 11:48:28 +01:00
H. Peter Anvin
638bee71c8 Merge branch 'x86/core' into x86/mce2 2009-02-24 16:11:51 -08:00
H. Peter Anvin
df20e2eb3e x86, mce, cmci: remove incorrect __cpuinit/__cpuexit annotations
Impact: Bug fix on UP

The MCE code is reinitialized from resume, so we can't use
__cpuinit/__cpuexit for most of the code.  Remove those annotations
for anything downstream of mce_init().

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-02-24 13:41:01 -08:00
Andi Kleen
88ccbedd9c x86, mce, cmci: add CMCI support
Impact: Major new feature

Intel CMCI (Corrected Machine Check Interrupt) is a new
feature on Nehalem CPUs. It allows the CPU to trigger
interrupts on corrected events, which allows faster
reaction to them instead of with the traditional
polling timer.

Also use CMCI to discover shared banks. Machine check banks
can be shared by CPU threads or even cores. Using the CMCI enable
bit it is possible to detect the fact that another CPU already
saw a specific bank. Use this to assign shared banks only
to one CPU to avoid reporting duplicated events.

On CPU hot unplug bank sharing is re discovered. This is done
using a thread that cycles through all the CPUs.

To avoid races between the poller and CMCI we only poll
for banks that are not CMCI capable and only check CMCI
owned banks on a interrupt.

The shared banks ownership information is currently only used for
CMCI interrupts, not polled banks.

The sharing discovery code follows the algorithm recommended in the
IA32 SDM Vol3a 14.5.2.1

The CMCI interrupt handler just calls the machine check poller to
pick up the machine check event that caused the interrupt.

I decided not to implement a separate threshold event like
the AMD version has, because the threshold is always one currently
and adding another event didn't seem to add any value.

Some code inspired by Yunhong Jiang's Xen implementation,
which was in term inspired by a earlier CMCI implementation
by me.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-02-24 13:41:00 -08:00
Andi Kleen
ee031c31d6 x86, mce, cmci: use polled banks bitmap in machine check poller
Define a per cpu bitmap that contains the banks polled by the machine
check poller. This is needed for the CMCI code in the next patches
to be able to disable polling on specific banks.

The bank by default contains all banks, so there is no behaviour
change. Only future code will remove some banks from the polling
set.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-02-24 13:26:05 -08:00
Andi Kleen
8457c84d68 x86, mce: replace machine check events logged interval with ratelimit
Impact: behavior change, use common code

Use a standard leaky bucket ratelimit for the machine check
warning print interval instead of waiting every check_interval.
Also decrease the limit to twice per minute.
This interacts better with threshold interrupts because
they can happen more often than check_interval.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-02-24 13:25:53 -08:00
Andi Kleen
f9695df42c x86, mce, cmci: avoid potential reentry of threshold interrupt
Impact: minor bugfix

The threshold handler on AMD (and soon on Intel) could be theoretically
reentered by the hardware. This could lead to corrupted events
because the machine check poll code assumes it is not reentered.

Move the APIC ACK to the end of the interrupt handler to let
the hardware avoid that.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-02-24 13:24:42 -08:00
Andi Kleen
b276268631 x86, mce, cmci: factor out threshold interrupt handler
Impact: cleanup; preparation for feature

The mce_amd_64 code has an own private MC threshold vector with an own
interrupt handler. Since Intel needs a similar handler
it makes sense to share the vector because both can not
be active at the same time.

I factored the common APIC handler code into a separate file which can
be used by both the Intel or AMD MC code.

This is needed for the next patch which adds an Intel specific
CMCI handler.

This patch should be a nop for AMD, it just moves some code
around.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-02-24 13:24:42 -08:00
Andi Kleen
41fdff322e x86, mce, cmci: export MAX_NR_BANKS
Impact: Cleanup (code movement)

Move MAX_NR_BANKS into mce.h because it's needed there
for followup patches.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-02-24 13:24:42 -08:00
Ingo Molnar
a852cbfaaf Merge branches 'x86/acpi', 'x86/apic', 'x86/asm', 'x86/cleanups', 'x86/mm', 'x86/signal' and 'x86/urgent'; commit 'v2.6.29-rc6' into x86/core 2009-02-24 21:50:43 +01:00
H. Peter Anvin
dc731ca609 Merge branch 'x86/urgent' into x86/mce2 2009-02-23 14:05:56 -08:00
H. Peter Anvin
ec5b3d3243 x86, mce: remove invalid __cpuinit/__cpuexit annotations
Impact: Bug fix when CPU hotplug is disabled

Correct the following broken __cpuinit/__cpuexit annotations:

- mce_cpu_features() is called from mce_resume(), and so cannot be
  __cpuinit.
- mce_disable_cpu() and mce_reenable_cpu() are called from
  mce_cpu_callback(), and so cannot be __cpuexit().

Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-02-23 14:01:04 -08:00
Ingo Molnar
fc6fc7f1b1 Merge branch 'linus' into x86/apic
Conflicts:
	arch/x86/mach-default/setup.c

Semantic conflict resolution:
	arch/x86/kernel/setup.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-22 20:05:19 +01:00
H. Peter Anvin
cc3ca22063 x86, mce: remove incorrect __cpuinit for mce_cpu_features()
Impact: Bug fix on UP

Checkin 6ec68bff3c:
    x86, mce: reinitialize per cpu features on resume

introduced a call to mce_cpu_features() in the resume path, in order
for the MCE machinery to get properly reinitialized after a resume.
However, this function (and its successors) was flagged __cpuinit,
which becomes __init on UP configurations (on SMP suspend/resume
requires CPU hotplug and so this would not be seen.)

Remove the offending __cpuinit annotations for mce_cpu_features() and
its successor functions.

Cc: Andi Kleen <ak@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-02-20 23:40:40 -08:00
Ingo Molnar
609162850d Merge branches 'x86/asm', 'x86/cleanups' and 'x86/headers' into x86/core 2009-02-20 17:40:50 +01:00
Ingo Molnar
3b6f7b9beb Merge branch 'x86/urgent' into x86/core 2009-02-20 17:40:43 +01:00
Vegard Nossum
ecab22aa6d x86: use symbolic constants for MSR_IA32_MISC_ENABLE bits
Impact: Cleanup. No functional changes.

Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-20 12:07:43 +01:00
H. Peter Anvin
f6d1826dfa x86, mce: use %ll instead of %L for 64-bit numbers
Impact: Cleanup

The standard spelling of a printf pattern for long long is "ll", not
"L", which is for long double.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-02-19 15:44:58 -08:00
Andi Kleen
b79109c3bb x86, mce: separate correct machine check poller and fatal exception handler
Impact: cleanup, performance enhancement

The machine check poller is diverging more and more from the fatal
exception handler. Instead of adding more special cases separate the code
paths completely. The corrected poll path is actually quite simple,
and this doesn't result in much code duplication.

This makes both handlers much easier to read and results in
cleaner code flow.  The exception handler now only needs to care
about uncorrected errors, which also simplifies the handling of multiple
errors. The corrected poller also now always runs in standard interrupt
context and does not need to do anything special to handle NMI context.

Minor behaviour changes:
- MCG status is now not cleared on polling.
- Only the banks which had corrected errors get cleared on polling
- The exception handler only clears banks with errors now

v2: Forward port to new patch order. Add "uc" argument.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-02-19 14:52:20 -08:00
Andi Kleen
b5f2fa4ea0 x86, mce: factor out duplicated struct mce setup into one function
Impact: cleanup

This merely factors out duplicated code to set up
the initial struct mce state into a single function.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-02-19 14:51:39 -08:00
Andi Kleen
0d7482e3d7 x86, mce: implement dynamic machine check banks support
Impact: cleanup; making code future proof; memory saving on small systems

This patch replaces the hardcoded max number of machine check banks with 
dynamic allocation depending on what the CPU reports. The sysfs
data structures and the banks array are dynamically allocated.

There is still a hard bank limit (128) because the mcelog protocol uses
banks >= 128 as pseudo banks to escape other events. But we expect
that 128 banks is beyond any reasonable CPU for now.

This supersedes an earlier patch by Venki, but it solves the problem
more completely by making the limit fully dynamic (up to the 128
boundary).

This saves some memory on machines with less than 6 banks because
they won't need sysdevs for unused ones and also allows to 
use sysfs to control these banks on possible future CPUs with
more than 6 banks.

This is an updated patch addressing Venki's comments.  I also added in
another patch from Thomas which fixed the error allocation path (that
patch was previously separated)

Cc: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-02-19 14:50:58 -08:00
Huang Ying
ef41df4344 x86, mce: fix a race condition in mce_read()
Impact: bugfix

Considering the situation as follow:

before: mcelog.next == 1, mcelog.entry[0].finished = 1

+--------------------------------------------------------------------------
R                   W1                  W2                  W3

read mcelog.next (1)
                    mcelog.next++ (2)
                    (working on entry 1,
                    finished == 0)

mcelog.next = 0
                                        mcelog.next++ (1)
                                        (working on entry 0)
                                                           mcelog.next++ (2)
                                                           (working on entry 1)
                        <----------------- race ---------------->
                    (done on entry 1,
                    finished = 1)
                                                           (done on entry 1,
                                                           finished = 1)

To fix the race condition, a cmpxchg loop is added to mce_read() to
ensure no new MCE record can be added between mcelog.next reading and
mcelog.next = 0.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-02-17 15:33:05 -08:00