linux/arch/x86
Fernando Luis Vázquez Cao 346b46be5f x86: Add per-cpu stat counter for APIC ICR read tries
In the IPI delivery slow path (NMI delivery) we retry the ICR
read to check for delivery completion a limited number of times.

[ The reason for the limited retries is that some of the places
  where it is used (cpu boot, kdump, etc) IPI delivery might not
  succeed (due to a firmware bug or system crash, for example)
  and in such a case it is better to give up and resume
  execution of other code. ]

This patch adds a new entry to /proc/interrupts, RTR, which
tells user space the number of times we retried the ICR read in
the IPI delivery slow path.

This should give some insight into how well the APIC
message delivery hardware is working - if the counts are way
too large then we are hitting a (very-) slow path way too
often.

Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Cc: Jörn Engel <joern@logfs.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/n/tip-vzsp20lo2xdzh5f70g0eis2s@git.kernel.org
[ extended the changelog ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-12-14 09:32:05 +01:00
..
boot doc: fix broken references 2011-09-27 18:08:04 +02:00
configs iommu: Rename the DMAR and INTR_REMAP config options 2011-09-21 10:22:03 +02:00
crypto Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
ia32 Cross Memory Attach 2011-10-31 17:30:44 -07:00
include/asm x86: Add per-cpu stat counter for APIC ICR read tries 2011-12-14 09:32:05 +01:00
kernel x86: Add per-cpu stat counter for APIC ICR read tries 2011-12-14 09:32:05 +01:00
kvm KVM: VMX: Check for automatic switch msr table overflow 2011-11-17 16:28:09 +02:00
lguest lguest: add export.h to lguest files for THIS_MODULE/EXPORT_SYMBOL 2011-10-31 19:32:13 -04:00
lib x86: Fix insn decoder for longer instruction 2011-10-10 09:05:51 +02:00
math-emu
mm thp: share get_huge_page_tail() 2011-11-02 16:06:58 -07:00
net net: filter: Just In Time compiler for x86-64 2011-04-27 23:05:08 -07:00
oprofile Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2011-10-26 17:03:38 +02:00
pci x86: Fix files explicitly requiring export.h for EXPORT_SYMBOL/THIS_MODULE 2011-10-31 19:30:35 -04:00
platform Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2011-11-18 22:16:18 -02:00
power x86: Fix files explicitly requiring export.h for EXPORT_SYMBOL/THIS_MODULE 2011-10-31 19:30:35 -04:00
tools
um fix braino in um patchset (mea culpa) 2011-11-21 12:10:21 -08:00
vdso Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2011-10-28 05:03:12 -07:00
video x86: fix up files really needing to include module.h 2011-10-31 19:30:36 -04:00
xen xen/pm_idle: Make pm_idle be default_idle under Xen. 2011-12-03 10:49:58 -08:00
.gitignore
Kbuild net: filter: Just In Time compiler for x86-64 2011-04-27 23:05:08 -07:00
Kconfig x86: Add NumaChip support 2011-12-05 17:17:24 +01:00
Kconfig.cpu x86: Add support for cmpxchg_double 2011-06-25 12:17:32 -07:00
Kconfig.debug doc: fix broken references 2011-09-27 18:08:04 +02:00
Makefile
Makefile.um um: take arch/um/sys-x86 to arch/x86/um 2011-11-02 14:15:05 +01:00
Makefile_32.cpu