diff options
| author | Nicholas Piggin <npiggin@gmail.com> | 2017-07-13 00:35:52 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-07-13 02:26:02 +0300 |
| commit | 2104180a53698df5aec35aed5f840a26ade0551d (patch) | |
| tree | 72fcbf52fd53a333282de9103197c04576025c54 /arch/powerpc/Kconfig | |
| parent | a10a842ff81a7e3810817b3b04e4c432b6191e21 (diff) | |
| download | linux-2104180a53698df5aec35aed5f840a26ade0551d.tar.xz | |
powerpc/64s: implement arch-specific hardlockup watchdog
Implement an arch-speicfic watchdog rather than use the perf-based
hardlockup detector.
The new watchdog takes the soft-NMI directly, rather than going through
perf. Perf interrupts are to be made maskable in future, so that would
prevent the perf detector from working in those regions.
Additionally, implement a SMP based detector where all CPUs watch one
another by pinging a shared cpumask. This is because powerpc Book3S
does not have a true periodic local NMI, but some platforms do implement
a true NMI IPI.
If a CPU is stuck with interrupts hard disabled, the soft-NMI watchdog
does not work, but the SMP watchdog will. Even on platforms without a
true NMI IPI to get a good trace from the stuck CPU, other CPUs will
notice the lockup sufficiently to report it and panic.
[npiggin@gmail.com: honor watchdog disable at boot/hotplug]
Link: http://lkml.kernel.org/r/20170621001346.5bb337c9@roar.ozlabs.ibm.com
[npiggin@gmail.com: fix false positive warning at CPU unplug]
Link: http://lkml.kernel.org/r/20170630080740.20766-1-npiggin@gmail.com
[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/20170616065715.18390-6-npiggin@gmail.com
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Don Zickus <dzickus@redhat.com>
Tested-by: Babu Moger <babu.moger@oracle.com> [sparc]
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/powerpc/Kconfig')
| -rw-r--r-- | arch/powerpc/Kconfig | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 63ed758e1d20..fce2f4f20891 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -82,7 +82,7 @@ config NR_IRQS config NMI_IPI bool - depends on SMP && (DEBUGGER || KEXEC_CORE) + depends on SMP && (DEBUGGER || KEXEC_CORE || HARDLOCKUP_DETECTOR) default y config STACKTRACE_SUPPORT @@ -192,12 +192,13 @@ config PPC select HAVE_MEMBLOCK select HAVE_MEMBLOCK_NODE_MAP select HAVE_MOD_ARCH_SPECIFIC - select HAVE_NMI if PERF_EVENTS + select HAVE_NMI if PERF_EVENTS || (PPC64 && PPC_BOOK3S) + select HAVE_HARDLOCKUP_DETECTOR_ARCH if (PPC64 && PPC_BOOK3S) select HAVE_OPROFILE select HAVE_OPTPROBES if PPC64 select HAVE_PERF_EVENTS select HAVE_PERF_EVENTS_NMI if PPC64 - select HAVE_HARDLOCKUP_DETECTOR_PERF if HAVE_PERF_EVENTS_NMI + select HAVE_HARDLOCKUP_DETECTOR_PERF if HAVE_PERF_EVENTS_NMI && !HAVE_HARDLOCKUP_DETECTOR_ARCH select HAVE_PERF_REGS select HAVE_PERF_USER_STACK_DUMP select HAVE_RCU_TABLE_FREE if SMP |