Keep a count of the machine check polls (or CMCI events) in
/proc/interrupts.

Andi needs this for debugging, but it's also useful in general
to see what's going in by the kernel.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NHidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Useful for debugging, but it's also good general policy
to have a counter for all special interrupts there. This makes it easier
to diagnose where a CPU is spending its time.

[ Impact: feature, debugging tool ]
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NHidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

The 64bit machine check code is in many ways much better than
the 32bit machine check code: it is more specification compliant,
is cleaner, only has a single code base versus one per CPU,
has better infrastructure for recovery, has a cleaner way to communicate
with user space etc. etc.

Use the 64bit code for 32bit too.

This is the second attempt to do this. There was one a couple of years
ago to unify this code for 32bit and 64bit.  Back then this ran into some
trouble with K7s and was reverted.

I believe this time the K7 problems (and some others) are addressed.
I went over the old handlers and was very careful to retain
all quirks.

But of course this needs a lot of testing on old systems. On newer
64bit capable systems I don't expect much problems because they have been
already tested with the 64bit kernel.

I made this a CONFIG for now that still allows to select the old
machine check code. This is mostly to make testing easier,
if someone runs into a problem we can ask them to try
with the CONFIG switched.

The new code is default y for more coverage.

Once there is confidence the 64bit code works well on older hardware
too the CONFIG_X86_OLD_MCE and the associated code can be easily
removed.

This causes a behaviour change for 32bit installations. They now
have to install the mcelog package to be able to log
corrected machine checks.

The 64bit machine check code only handles CPUs which support the
standard Intel machine check architecture described in the IA32 SDM.
The 32bit code has special support for some older CPUs which
have non standard machine check architectures, in particular
WinChip C3 and Intel P5.  I made those a separate CONFIG option
and kept them for now. The WinChip variant could be probably
removed without too much pain, it doesn't really do anything
interesting. P5 is also disabled by default (like it
was before) because many motherboards have it miswired, but
according to Alan Cox a few embedded setups use that one.

Forward ported/heavily changed version of old patch, original patch
included review/fixes from Thomas Gleixner, Bert Wesarg.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NHidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Impact: refactor, speed up and robustize code

In case if apic was disabled by kernel option
or by hardware limits we can use dummy operations
in apic->write to simplify the ack_APIC_irq() code.

At the lame time the patch fixes the missed EOI in
do_IRQ function (which has place if kernel is compiled
as X86-32 and interrupt without handler happens where
apic was not asked to be disabled via kernel option).

Note that native_apic_write_dummy() consists of
WARN_ON_ONCE to catch any buggy writes on enabled
APICs. Could be removed after some time of testing.
Signed-off-by: NCyrill Gorcunov <gorcunov@openvz.org>
LKML-Reference: <20090412165058.724788431@openvz.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup, robustization

 1) guard ack_bad_irq with printk_ratelimit since there is no
    guarantee we will not be flooded one day

 2) use pr_emerg() helper
Signed-off-by: NCyrill Gorcunov <gorcunov@openvz.org>
LKML-Reference: <20090412165058.277579847@openvz.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Now /proc/interrupts of tip tree has new counters:

  PLT: Platform interrupts

Format change of output, as like that by commit:

  commit 7a81d9a7
  x86: smarten /proc/interrupts output

should be applied to these new counters too.
Signed-off-by: NHidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Jan Beulich <jbeulich@novell.com>
LKML-Reference: <49C98DEA.8060208@jp.fujitsu.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

keep CONFIG_X86_LOCAL_APIC interrupts together to avoid extra ifdef
Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>

Impact: cleanup

SMP and !SMP will use same path for show_interrupts
Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>

Impact: change /proc/interrupts output ABI

With the number of interrupts on large systems growing, assumptions on
the width an interrupt number requires when converted to a decimal
string turn invalid. Therefore, calculate the maximum number of digits
dynamically.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
LKML-Reference: <49B911EB.76E4.0078.0@novell.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch allocates a system interrupt vector for various platform
specific uses.
Signed-off-by: NDimitri Sivanich <sivanich@sgi.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: john stultz <johnstul@us.ibm.com>
LKML-Reference: <20090304185605.GA24419@sgi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

Remove genapic.h and remove all references to it.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

make it simpler, don't need have one extra struct.

v2: fix the sgi_uv build
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

With the differences in interrupt handling hoisted into handle_irq(),
do_IRQ is more or less identical between 32 and 64 bit, so unify it.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NBrian Gerst <brgerst@gmail.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

Impact: cleanup

Fix:

 WARNING: Use #include <linux/smp.h> instead of <asm/smp.h>

 total: 0 errors, 1 warnings
Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: build fix

lguest can be built as a module and makes use of this new symbol:

ERROR: "vector_used_by_percpu_irq" [drivers/lguest/lg.ko] undefined!

export it.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: new feature

Problem on distro kernels: irq_desc[NR_IRQS] takes megabytes of RAM with
NR_CPUS set to large values. The goal is to be able to scale up to much
larger NR_IRQS value without impacting the (important) common case.

To solve this, we generalize irq_desc[NR_IRQS] to an (optional) array of
irq_desc pointers.

When CONFIG_SPARSE_IRQ=y is used, we use kzalloc_node to get irq_desc,
this also makes the IRQ descriptors NUMA-local (to the site that calls
request_irq()).

This gets rid of the irq_cfg[] static array on x86 as well: irq_cfg now
uses desc->chip_data for x86 to store irq_cfg.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Fix off-by-one in for_each_irq_desc_reverse().

Impact is near zero in practice, because nothing substantial wants to
iterate down to IRQ#0 - but fix it nevertheless.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Share more duplicated code.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

show_interrupts() and proc helpers are basically the same for
32 and 64 bit. Move them to a shared source file.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>