From: Mark Rutland Date: Tue, 17 May 2011 08:15:38 +0000 (+0100) Subject: ARM: 6902/1: perf: Remove erroneous check on active_events X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=57ce9bb39b476accf8fba6e16aea67ed76ea523d;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git ARM: 6902/1: perf: Remove erroneous check on active_events When initialising a PMU, there is a check to protect against races with other CPUs filling all of the available event slots. Since armpmu_add checks that an event can be scheduled, we do not need to do this at initialisation time. Furthermore the current code is broken because it assumes that atomic_inc_not_zero will unconditionally increment active_counts and then tries to decrement it again on failure. This patch removes the broken, redundant code. Signed-off-by: Mark Rutland Acked-by: Will Deacon Cc: Jamie Iles Signed-off-by: Russell King --- diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c index 139e3c827369..d53c0abc4dd3 100644 --- a/arch/arm/kernel/perf_event.c +++ b/arch/arm/kernel/perf_event.c @@ -560,11 +560,6 @@ static int armpmu_event_init(struct perf_event *event) event->destroy = hw_perf_event_destroy; if (!atomic_inc_not_zero(&active_events)) { - if (atomic_read(&active_events) > armpmu->num_events) { - atomic_dec(&active_events); - return -ENOSPC; - } - mutex_lock(&pmu_reserve_mutex); if (atomic_read(&active_events) == 0) { err = armpmu_reserve_hardware();