Commit-ID: 53b25335dd60981ad608da7890420898a34469a6 Gitweb: http://git.kernel.org/tip/53b25335dd60981ad608da7890420898a34469a6 Author: Vince Weaver <vincent.wea...@maine.edu> AuthorDate: Fri, 16 May 2014 17:12:12 -0400 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Thu, 5 Jun 2014 12:29:55 +0200
perf: Disable sampled events if no PMU interrupt Add common code to generate -ENOTSUPP at event creation time if an architecture attempts to create a sampled event and PERF_PMU_NO_INTERRUPT is set. This adds a new pmu->capabilities flag. Initially we only support PERF_PMU_NO_INTERRUPT (to indicate a PMU has no support for generating hardware interrupts) but there are other capabilities that can be added later. Signed-off-by: Vince Weaver <vincent.wea...@maine.edu> Acked-by: Will Deacon <will.dea...@arm.com> [peterz: rename to PERF_PMU_CAP_* and moved the pmu::capabilities word into a hole] Signed-off-by: Peter Zijlstra <pet...@infradead.org> Cc: Arnaldo Carvalho de Melo <a...@kernel.org> Cc: Linus Torvalds <torva...@linux-foundation.org> Link: http://lkml.kernel.org/r/alpine.deb.2.10.1405161708060.11...@vincent-weaver-1.umelst.maine.edu Signed-off-by: Ingo Molnar <mi...@kernel.org> Signed-off-by: Ingo Molnar <mi...@kernel.org> --- include/linux/perf_event.h | 10 ++++++++++ kernel/events/core.c | 7 +++++++ 2 files changed, 17 insertions(+) diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index af6dcf1..267c8f3 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -167,6 +167,11 @@ struct perf_event; #define PERF_EVENT_TXN 0x1 /** + * pmu::capabilities flags + */ +#define PERF_PMU_CAP_NO_INTERRUPT 0x01 + +/** * struct pmu - generic performance monitoring unit */ struct pmu { @@ -178,6 +183,11 @@ struct pmu { const char *name; int type; + /* + * various common per-pmu feature flags + */ + int capabilities; + int * __percpu pmu_disable_count; struct perf_cpu_context * __percpu pmu_cpu_context; int task_ctx_nr; diff --git a/kernel/events/core.c b/kernel/events/core.c index a62d142..e9ef0c6 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -7120,6 +7120,13 @@ SYSCALL_DEFINE5(perf_event_open, } } + if (is_sampling_event(event)) { + if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { + err = -ENOTSUPP; + goto err_alloc; + } + } + account_event(event); /* -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
