redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

powerpc, perf: Fix frequency calculation for overflowing counters (FSL version) 

When fixing the frequency calculations for perf on powerpc I
forgot to fix the FSL version.

If we dont set event->hw.last_period the frequency to period
calculations in perf go haywire and we continually
throttle/unthrottle the PMU.

Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Scott Wood <scottwood@freescale.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20110118214404.2f42e634@kryten>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
hifive-unleashed-5.1
Anton Blanchard 2011-01-18 21:44:04 +11:00 committed by Ingo Molnar
parent 8550d7cb6e
commit 8c8a9b25b5
1 changed files with 1 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
arch/powerpc/kernel/perf_event_fsl_emb.c
View File

@ -596,6 +596,7 @@ static void record_and_restart(struct perf_event *event, unsigned long val,
if (left <= 0)
left = period;
record = 1;
event->hw.last_period = event->hw.sample_period;
}
if (left < 0x80000000LL)
val = 0x80000000LL - left;