From 6759788b944139793bffa889761cc3d8d703fdc0 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Tue, 5 Apr 2011 14:01:24 +0100 Subject: [PATCH] ARM: 6865/1: perf: ensure pass through zero is counted on overflow Commit a737823d ("ARM: perf: ensure overflows aren't missed due to IRQ latency") changed the way that event deltas are calculated on overflow so that we don't miss events when the new count value overtakes the previous one. Unfortunately, we forget to count the event that passes through zero so we end up being off by 1. This patch adds on the correction. Reported-by: Chris Moore Signed-off-by: Will Deacon Signed-off-by: Russell King --- arch/arm/kernel/perf_event.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c index 69cfee0fe00..979da3947f4 100644 --- a/arch/arm/kernel/perf_event.c +++ b/arch/arm/kernel/perf_event.c @@ -221,7 +221,7 @@ again: prev_raw_count &= armpmu->max_period; if (overflow) - delta = armpmu->max_period - prev_raw_count + new_raw_count; + delta = armpmu->max_period - prev_raw_count + new_raw_count + 1; else delta = new_raw_count - prev_raw_count; -- 2.20.1