From: Will Deacon Date: Tue, 19 Jul 2011 21:43:28 +0000 (+0100) Subject: ARM: perf: index PMU registers from zero X-Git-Url: https://openfabrics.org/gitweb/?a=commitdiff_plain;h=ecf5a893211c26e02b9d4cfd6ba2183473ac0203;p=~shefty%2Frdma-dev.git ARM: perf: index PMU registers from zero ARM PMU code used to use 1-based indices for PMU registers. This caused several data structures (pmu_hw_events::{active_events, used_mask, events}) to have an unused element at index zero. ARMPMU_MAX_HWEVENTS still takes this indexing into account, and currently equates to 33. This patch updates the core ARM perf code to use the 0th index again. Acked-by: Jamie Iles Reviewed-by: Jean Pihet Signed-off-by: Mark Rutland Signed-off-by: Will Deacon --- diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c index d507fe148e0..c668c91d0c0 100644 --- a/arch/arm/kernel/perf_event.c +++ b/arch/arm/kernel/perf_event.c @@ -35,7 +35,7 @@ static struct platform_device *pmu_device; static DEFINE_RAW_SPINLOCK(pmu_lock); /* - * ARMv6 supports a maximum of 3 events, starting from index 1. If we add + * ARMv6 supports a maximum of 3 events, starting from index 0. If we add * another platform that supports more, we need to increase this to be the * largest of all platforms. * @@ -43,13 +43,12 @@ static DEFINE_RAW_SPINLOCK(pmu_lock); * cycle counter CCNT + 31 events counters CNT0..30. * Cortex-A8 has 1+4 counters, Cortex-A9 has 1+6 counters. */ -#define ARMPMU_MAX_HWEVENTS 33 +#define ARMPMU_MAX_HWEVENTS 32 /* The events for a given CPU. */ struct cpu_hw_events { /* - * The events that are active on the CPU for the given index. Index 0 - * is reserved. + * The events that are active on the CPU for the given index. */ struct perf_event *events[ARMPMU_MAX_HWEVENTS]; @@ -597,7 +596,7 @@ static void armpmu_enable(struct pmu *pmu) if (!armpmu) return; - for (idx = 0; idx <= armpmu->num_events; ++idx) { + for (idx = 0; idx < armpmu->num_events; ++idx) { struct perf_event *event = cpuc->events[idx]; if (!event)