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| author | Anton Blanchard <[email protected]> | 2012-02-15 18:48:22 +0000 |
|---|---|---|
| committer | Benjamin Herrenschmidt <[email protected]> | 2012-02-16 05:24:35 +0000 |
| commit | 9a45a9407c69d068500923480884661e2b9cc421 (patch) | |
| tree | 8ff43b5fd98ab68352dc4dd0823401a5736afab2 /lib/flex_array.c | |
| parent | powerpc/adb: Use set_current_state() (diff) | |
| download | kernel-9a45a9407c69d068500923480884661e2b9cc421.tar.gz kernel-9a45a9407c69d068500923480884661e2b9cc421.zip | |
powerpc/perf: power_pmu_start restores incorrect values, breaking frequency events
perf on POWER stopped working after commit e050e3f0a71b (perf: Fix
broken interrupt rate throttling). That patch exposed a bug in
the POWER perf_events code.
Since the PMCs count upwards and take an exception when the top bit
is set, we want to write 0x80000000 - left in power_pmu_start. We were
instead programming in left which effectively disables the counter
until we eventually hit 0x80000000. This could take seconds or longer.
With the patch applied I get the expected number of samples:
SAMPLE events: 9948
Signed-off-by: Anton Blanchard <[email protected]>
Acked-by: Paul Mackerras <[email protected]>
Signed-off-by: Benjamin Herrenschmidt <[email protected]>
Cc: <[email protected]>
Diffstat (limited to 'lib/flex_array.c')
0 files changed, 0 insertions, 0 deletions