diff options
| author | Michael Ellerman <mpe@ellerman.id.au> | 2014-03-14 09:00:34 +0400 |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2014-03-24 02:48:27 +0400 |
| commit | 76cb8a783a4b7403a6731ffdeec0831cd4b19936 (patch) | |
| tree | 03418d8204460f19b74ed88b453c3c5827dc32fa /arch/powerpc/perf | |
| parent | ba969237cfba17fcf0de8596b128f68259293137 (diff) | |
| download | linux-76cb8a783a4b7403a6731ffdeec0831cd4b19936.tar.xz | |
powerpc/perf: Enable BHRB access for EBB events
The previous commit added constraint and register handling to allow
processes using EBB (Event Based Branches) to request access to the BHRB
(Branch History Rolling Buffer).
With that in place we can allow processes using EBB to access the BHRB.
This is achieved by setting BHRBA in MMCR0 when we enable EBB access. We
must also clear BHRBA when we are disabling.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/perf')
| -rw-r--r-- | arch/powerpc/perf/core-book3s.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c index 1e095fd68b6c..4520c9356b54 100644 --- a/arch/powerpc/perf/core-book3s.c +++ b/arch/powerpc/perf/core-book3s.c @@ -78,6 +78,7 @@ static unsigned int freeze_events_kernel = MMCR0_FCS; #define MMCR0_FC56 0 #define MMCR0_PMAO 0 #define MMCR0_EBE 0 +#define MMCR0_BHRBA 0 #define MMCR0_PMCC 0 #define MMCR0_PMCC_U6 0 @@ -546,8 +547,8 @@ static unsigned long ebb_switch_in(bool ebb, unsigned long mmcr0) if (!ebb) goto out; - /* Enable EBB and read/write to all 6 PMCs for userspace */ - mmcr0 |= MMCR0_EBE | MMCR0_PMCC_U6; + /* Enable EBB and read/write to all 6 PMCs and BHRB for userspace */ + mmcr0 |= MMCR0_EBE | MMCR0_BHRBA | MMCR0_PMCC_U6; /* * Add any bits from the user MMCR0, FC or PMAO. This is compatible @@ -1117,11 +1118,12 @@ static void power_pmu_disable(struct pmu *pmu) } /* - * Set the 'freeze counters' bit, clear EBE/PMCC/PMAO/FC56. + * Set the 'freeze counters' bit, clear EBE/BHRBA/PMCC/PMAO/FC56 */ val = mmcr0 = mfspr(SPRN_MMCR0); val |= MMCR0_FC; - val &= ~(MMCR0_EBE | MMCR0_PMCC | MMCR0_PMAO | MMCR0_FC56); + val &= ~(MMCR0_EBE | MMCR0_BHRBA | MMCR0_PMCC | MMCR0_PMAO | + MMCR0_FC56); /* * The barrier is to make sure the mtspr has been |