From 04a705df47d1ea27ca2b066f24b1951c51792d0d Mon Sep 17 00:00:00 2001 From: Stephane Eranian Date: Tue, 6 Oct 2009 16:42:08 +0200 Subject: [PATCH] perf_events: Check for filters on fixed counter events Intel fixed counters do not support all the filters possible with a generic counter. Thus, if a fixed counter event is passed but with certain filters set, then the fixed_mode_idx() function must fail and the event must be measured in a generic counter instead. Reject filters are: inv, edge, cnt-mask. Signed-off-by: Stephane Eranian Signed-off-by: Peter Zijlstra LKML-Reference: <1254840129-6198-2-git-send-email-eranian@gmail.com> Signed-off-by: Ingo Molnar --- arch/x86/include/asm/perf_event.h | 13 ++++++++++++- arch/x86/kernel/cpu/perf_event.c | 6 ++++++ 2 files changed, 18 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h index ad7ce3fd506..8d9f8548a87 100644 --- a/arch/x86/include/asm/perf_event.h +++ b/arch/x86/include/asm/perf_event.h @@ -28,9 +28,20 @@ */ #define ARCH_PERFMON_EVENT_MASK 0xffff +/* + * filter mask to validate fixed counter events. + * the following filters disqualify for fixed counters: + * - inv + * - edge + * - cnt-mask + * The other filters are supported by fixed counters. + * The any-thread option is supported starting with v3. + */ +#define ARCH_PERFMON_EVENT_FILTER_MASK 0xff840000 + #define ARCH_PERFMON_UNHALTED_CORE_CYCLES_SEL 0x3c #define ARCH_PERFMON_UNHALTED_CORE_CYCLES_UMASK (0x00 << 8) -#define ARCH_PERFMON_UNHALTED_CORE_CYCLES_INDEX 0 +#define ARCH_PERFMON_UNHALTED_CORE_CYCLES_INDEX 0 #define ARCH_PERFMON_UNHALTED_CORE_CYCLES_PRESENT \ (1 << (ARCH_PERFMON_UNHALTED_CORE_CYCLES_INDEX)) diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c index b5801c31184..1d16bd69551 100644 --- a/arch/x86/kernel/cpu/perf_event.c +++ b/arch/x86/kernel/cpu/perf_event.c @@ -1349,6 +1349,12 @@ fixed_mode_idx(struct perf_event *event, struct hw_perf_event *hwc) if (!x86_pmu.num_events_fixed) return -1; + /* + * fixed counters do not take all possible filters + */ + if (hwc->config & ARCH_PERFMON_EVENT_FILTER_MASK) + return -1; + if (unlikely(hw_event == x86_pmu.event_map(PERF_COUNT_HW_INSTRUCTIONS))) return X86_PMC_IDX_FIXED_INSTRUCTIONS; if (unlikely(hw_event == x86_pmu.event_map(PERF_COUNT_HW_CPU_CYCLES))) -- 2.39.3