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| author | Max Filippov <jcmvbkbc@gmail.com> | 2015-07-16 10:37:31 +0300 |
|---|---|---|
| committer | Max Filippov <jcmvbkbc@gmail.com> | 2015-08-17 07:33:39 +0300 |
| commit | 38fef73c21d117cf992fb5ec6e30630e54e13f4f (patch) | |
| tree | ca3aae4c2e29ee81c66dcc16eb835e0b8c4e631f /arch/xtensa/kernel/perf_event.c | |
| parent | 98e298329e7b391293da5097817437292c842dc9 (diff) | |
| download | blackbird-op-linux-38fef73c21d117cf992fb5ec6e30630e54e13f4f.tar.gz blackbird-op-linux-38fef73c21d117cf992fb5ec6e30630e54e13f4f.zip | |
xtensa: implement fake NMI
In case perf IRQ is the highest of the medium-level IRQs, and is alone
on its level, it may be treated as NMI:
- LOCKLEVEL is defined to be one level less than EXCM level,
- IRQ masking never lowers current IRQ level,
- new fake exception cause code, EXCCAUSE_MAPPED_NMI is assigned to that
IRQ; new second level exception handler, do_nmi, assigned to it
handles it as NMI,
- atomic operations in configurations without s32c1i still need to mask
all interrupts.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Diffstat (limited to 'arch/xtensa/kernel/perf_event.c')
| -rw-r--r-- | arch/xtensa/kernel/perf_event.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/arch/xtensa/kernel/perf_event.c b/arch/xtensa/kernel/perf_event.c index b44df3c8198f..54f01188c29c 100644 --- a/arch/xtensa/kernel/perf_event.c +++ b/arch/xtensa/kernel/perf_event.c @@ -359,7 +359,7 @@ void perf_event_print_debug(void) local_irq_restore(flags); } -static irqreturn_t xtensa_pmu_irq_handler(int irq, void *dev_id) +irqreturn_t xtensa_pmu_irq_handler(int irq, void *dev_id) { irqreturn_t rc = IRQ_NONE; struct xtensa_pmu_events *ev = this_cpu_ptr(&xtensa_pmu_events); @@ -436,10 +436,14 @@ static int __init xtensa_pmu_init(void) int irq = irq_create_mapping(NULL, XCHAL_PROFILING_INTERRUPT); perf_cpu_notifier(xtensa_pmu_notifier); +#if XTENSA_FAKE_NMI + enable_irq(irq); +#else ret = request_irq(irq, xtensa_pmu_irq_handler, IRQF_PERCPU, "pmu", NULL); if (ret < 0) return ret; +#endif ret = perf_pmu_register(&xtensa_pmu, "cpu", PERF_TYPE_RAW); if (ret) |
