linux/arch/powerpc/perf
Michael Neuling bc09c219b2 powerpc/perf: Fix finding overflowed PMC in interrupt
If a PMC is about to overflow on a counter that's on an active perf event
(ie. less than 256 from the end) and a _different_ PMC overflows just at this
time (a PMC that's not on an active perf event), we currently mark the event as
found, but in reality it's not as it's likely the other PMC that caused the
IRQ.  Since we mark it as found the second catch all for overflows doesn't run,
and we don't reset the overflowing PMC ever.  Hence we keep hitting that same
PMC IRQ over and over and don't reset the actual overflowing counter.

This is a rewrite of the perf interrupt handler for book3s to get around this.
We now check to see if any of the PMCs have actually overflowed (ie >=
0x80000000).  If yes, record it for active counters and just reset it for
inactive counters.  If it's not overflowed, then we check to see if it's one of
the buggy power7 counters and if it is, record it and continue.  If none of the
PMCs match this, then we make note that we couldn't find the PMC that caused
the IRQ.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Reviewed-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
cc: Paul Mackerras <paulus@samba.org>
cc: Anton Blanchard <anton@samba.org>
cc: Linux PPC dev <linuxppc-dev@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-01-10 17:02:01 +11:00
..
callchain.c powerpc/perf: Use perf_instruction_pointer in callchains 2012-07-10 19:18:46 +10:00
core-book3s.c powerpc/perf: Fix finding overflowed PMC in interrupt 2013-01-10 17:02:01 +11:00
core-fsl-emb.c perf: Pass last sampling period to perf_sample_data_init() 2012-05-09 15:23:12 +02:00
e500-pmu.c powerpc/perf: Add stalled-cycles events 2013-01-10 17:00:56 +11:00
Makefile
mpc7450-pmu.c
power4-pmu.c powerpc/perf: Fix instruction address sampling on 970 and Power4 2012-03-28 11:33:24 +11:00
power5-pmu.c
power5+-pmu.c
power6-pmu.c
power7-pmu.c powerpc/perf: Add missing L2 constraint handling in Power7 PMU 2012-11-15 13:00:36 +11:00
ppc970-pmu.c powerpc/perf: Fix instruction address sampling on 970 and Power4 2012-03-28 11:33:24 +11:00