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| author | Michael Ellerman <michael@ellerman.id.au> | 2013-06-28 12:15:12 +0400 |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2013-07-01 05:49:57 +0400 |
| commit | 7a7a41f9d5b28ac3a916b057a7d3cd3f435ee9a6 (patch) | |
| tree | 10a75b68f94e6b947632d568fc4552325d35e62d /arch/powerpc/perf/power8-pmu.c | |
| parent | 378a6ee99e4a431ec84e4e61893445c041c93007 (diff) | |
| download | linux-7a7a41f9d5b28ac3a916b057a7d3cd3f435ee9a6.tar.xz | |
powerpc/perf: Freeze PMC5/6 if we're not using them
On Power8 we can freeze PMC5 and 6 if we're not using them. Normally they
run all the time.
As noticed by Anshuman, we should unfreeze them when we disable the PMU
as there are legacy tools which expect them to run all the time.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
CC: <stable@vger.kernel.org> [v3.10]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/perf/power8-pmu.c')
| -rw-r--r-- | arch/powerpc/perf/power8-pmu.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/powerpc/perf/power8-pmu.c b/arch/powerpc/perf/power8-pmu.c index 84cdc6d892e3..d59f5b2d4c2f 100644 --- a/arch/powerpc/perf/power8-pmu.c +++ b/arch/powerpc/perf/power8-pmu.c @@ -391,6 +391,10 @@ static int power8_compute_mmcr(u64 event[], int n_ev, if (pmc_inuse & 0x7c) mmcr[0] |= MMCR0_PMCjCE; + /* If we're not using PMC 5 or 6, freeze them */ + if (!(pmc_inuse & 0x60)) + mmcr[0] |= MMCR0_FC56; + mmcr[1] = mmcr1; mmcr[2] = mmcra; |