From: Will Deacon Date: Tue, 5 Apr 2011 13:01:24 +0000 (+0100) Subject: ARM: 6865/1: perf: ensure pass through zero is counted on overflow X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=6759788b944139793bffa889761cc3d8d703fdc0;p=linux-beck.git 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 --- diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c index 69cfee0fe00f..979da3947f42 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;