Message ID | 20190511024217.4013-2-ravi.bangoria@linux.ibm.com (mailing list archive) |
---|---|
State | Accepted |
Commit | 3202e35ec1c8fc19cea24253ff83edf702a60a02 |
Headers | show |
Series | [1/2] perf ioctl: Add check for the sample_period value | expand |
Context | Check | Description |
---|---|---|
snowpatch_ozlabs/apply_patch | success | Successfully applied on branch next (8150a153c013aa2dd1ffae43370b89ac1347a7fb) |
snowpatch_ozlabs/build-ppc64le | success | Build succeeded |
snowpatch_ozlabs/build-ppc64be | success | Build succeeded |
snowpatch_ozlabs/build-ppc64e | success | Build succeeded |
snowpatch_ozlabs/build-pmac32 | success | Build succeeded |
snowpatch_ozlabs/checkpatch | warning | total: 0 errors, 0 warnings, 1 checks, 53 lines checked |
On 5/11/19 8:12 AM, Ravi Bangoria wrote: > Consider a scenario where user creates two events: > > 1st event: > attr.sample_type |= PERF_SAMPLE_BRANCH_STACK; > attr.branch_sample_type = PERF_SAMPLE_BRANCH_ANY; > fd = perf_event_open(attr, 0, 1, -1, 0); > > This sets cpuhw->bhrb_filter to 0 and returns valid fd. > > 2nd event: > attr.sample_type |= PERF_SAMPLE_BRANCH_STACK; > attr.branch_sample_type = PERF_SAMPLE_BRANCH_CALL; > fd = perf_event_open(attr, 0, 1, -1, 0); > > It overrides cpuhw->bhrb_filter to -1 and returns with error. > > Now if power_pmu_enable() gets called by any path other than > power_pmu_add(), ppmu->config_bhrb(-1) will set mmcra to -1. > > Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Fixes: 3925f46bb590 ("powerpc/perf: Enable branch stack sampling framework")
On 11/05/19 8:12 AM, Ravi Bangoria wrote: > Consider a scenario where user creates two events: > > 1st event: > attr.sample_type |= PERF_SAMPLE_BRANCH_STACK; > attr.branch_sample_type = PERF_SAMPLE_BRANCH_ANY; > fd = perf_event_open(attr, 0, 1, -1, 0); > > This sets cpuhw->bhrb_filter to 0 and returns valid fd. > > 2nd event: > attr.sample_type |= PERF_SAMPLE_BRANCH_STACK; > attr.branch_sample_type = PERF_SAMPLE_BRANCH_CALL; > fd = perf_event_open(attr, 0, 1, -1, 0); > > It overrides cpuhw->bhrb_filter to -1 and returns with error. > > Now if power_pmu_enable() gets called by any path other than > power_pmu_add(), ppmu->config_bhrb(-1) will set mmcra to -1. Reviewed-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> > Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> > --- > arch/powerpc/perf/core-book3s.c | 6 ++++-- > arch/powerpc/perf/power8-pmu.c | 3 +++ > arch/powerpc/perf/power9-pmu.c | 3 +++ > 3 files changed, 10 insertions(+), 2 deletions(-) > > diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c > index b0723002a396..8eb5dc5df62b 100644 > --- a/arch/powerpc/perf/core-book3s.c > +++ b/arch/powerpc/perf/core-book3s.c > @@ -1846,6 +1846,7 @@ static int power_pmu_event_init(struct perf_event *event) > int n; > int err; > struct cpu_hw_events *cpuhw; > + u64 bhrb_filter; > > if (!ppmu) > return -ENOENT; > @@ -1951,13 +1952,14 @@ static int power_pmu_event_init(struct perf_event *event) > err = power_check_constraints(cpuhw, events, cflags, n + 1); > > if (has_branch_stack(event)) { > - cpuhw->bhrb_filter = ppmu->bhrb_filter_map( > + bhrb_filter = ppmu->bhrb_filter_map( > event->attr.branch_sample_type); > > - if (cpuhw->bhrb_filter == -1) { > + if (bhrb_filter == -1) { > put_cpu_var(cpu_hw_events); > return -EOPNOTSUPP; > } > + cpuhw->bhrb_filter = bhrb_filter; > } > > put_cpu_var(cpu_hw_events); > diff --git a/arch/powerpc/perf/power8-pmu.c b/arch/powerpc/perf/power8-pmu.c > index d12a2db26353..d10feef93b6b 100644 > --- a/arch/powerpc/perf/power8-pmu.c > +++ b/arch/powerpc/perf/power8-pmu.c > @@ -29,6 +29,7 @@ enum { > #define POWER8_MMCRA_IFM1 0x0000000040000000UL > #define POWER8_MMCRA_IFM2 0x0000000080000000UL > #define POWER8_MMCRA_IFM3 0x00000000C0000000UL > +#define POWER8_MMCRA_BHRB_MASK 0x00000000C0000000UL > > /* > * Raw event encoding for PowerISA v2.07 (Power8): > @@ -243,6 +244,8 @@ static u64 power8_bhrb_filter_map(u64 branch_sample_type) > > static void power8_config_bhrb(u64 pmu_bhrb_filter) > { > + pmu_bhrb_filter &= POWER8_MMCRA_BHRB_MASK; > + > /* Enable BHRB filter in PMU */ > mtspr(SPRN_MMCRA, (mfspr(SPRN_MMCRA) | pmu_bhrb_filter)); > } > diff --git a/arch/powerpc/perf/power9-pmu.c b/arch/powerpc/perf/power9-pmu.c > index 030544e35959..f3987915cadc 100644 > --- a/arch/powerpc/perf/power9-pmu.c > +++ b/arch/powerpc/perf/power9-pmu.c > @@ -92,6 +92,7 @@ enum { > #define POWER9_MMCRA_IFM1 0x0000000040000000UL > #define POWER9_MMCRA_IFM2 0x0000000080000000UL > #define POWER9_MMCRA_IFM3 0x00000000C0000000UL > +#define POWER9_MMCRA_BHRB_MASK 0x00000000C0000000UL > > /* Nasty Power9 specific hack */ > #define PVR_POWER9_CUMULUS 0x00002000 > @@ -300,6 +301,8 @@ static u64 power9_bhrb_filter_map(u64 branch_sample_type) > > static void power9_config_bhrb(u64 pmu_bhrb_filter) > { > + pmu_bhrb_filter &= POWER9_MMCRA_BHRB_MASK; > + > /* Enable BHRB filter in PMU */ > mtspr(SPRN_MMCRA, (mfspr(SPRN_MMCRA) | pmu_bhrb_filter)); > }
diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c index b0723002a396..8eb5dc5df62b 100644 --- a/arch/powerpc/perf/core-book3s.c +++ b/arch/powerpc/perf/core-book3s.c @@ -1846,6 +1846,7 @@ static int power_pmu_event_init(struct perf_event *event) int n; int err; struct cpu_hw_events *cpuhw; + u64 bhrb_filter; if (!ppmu) return -ENOENT; @@ -1951,13 +1952,14 @@ static int power_pmu_event_init(struct perf_event *event) err = power_check_constraints(cpuhw, events, cflags, n + 1); if (has_branch_stack(event)) { - cpuhw->bhrb_filter = ppmu->bhrb_filter_map( + bhrb_filter = ppmu->bhrb_filter_map( event->attr.branch_sample_type); - if (cpuhw->bhrb_filter == -1) { + if (bhrb_filter == -1) { put_cpu_var(cpu_hw_events); return -EOPNOTSUPP; } + cpuhw->bhrb_filter = bhrb_filter; } put_cpu_var(cpu_hw_events); diff --git a/arch/powerpc/perf/power8-pmu.c b/arch/powerpc/perf/power8-pmu.c index d12a2db26353..d10feef93b6b 100644 --- a/arch/powerpc/perf/power8-pmu.c +++ b/arch/powerpc/perf/power8-pmu.c @@ -29,6 +29,7 @@ enum { #define POWER8_MMCRA_IFM1 0x0000000040000000UL #define POWER8_MMCRA_IFM2 0x0000000080000000UL #define POWER8_MMCRA_IFM3 0x00000000C0000000UL +#define POWER8_MMCRA_BHRB_MASK 0x00000000C0000000UL /* * Raw event encoding for PowerISA v2.07 (Power8): @@ -243,6 +244,8 @@ static u64 power8_bhrb_filter_map(u64 branch_sample_type) static void power8_config_bhrb(u64 pmu_bhrb_filter) { + pmu_bhrb_filter &= POWER8_MMCRA_BHRB_MASK; + /* Enable BHRB filter in PMU */ mtspr(SPRN_MMCRA, (mfspr(SPRN_MMCRA) | pmu_bhrb_filter)); } diff --git a/arch/powerpc/perf/power9-pmu.c b/arch/powerpc/perf/power9-pmu.c index 030544e35959..f3987915cadc 100644 --- a/arch/powerpc/perf/power9-pmu.c +++ b/arch/powerpc/perf/power9-pmu.c @@ -92,6 +92,7 @@ enum { #define POWER9_MMCRA_IFM1 0x0000000040000000UL #define POWER9_MMCRA_IFM2 0x0000000080000000UL #define POWER9_MMCRA_IFM3 0x00000000C0000000UL +#define POWER9_MMCRA_BHRB_MASK 0x00000000C0000000UL /* Nasty Power9 specific hack */ #define PVR_POWER9_CUMULUS 0x00002000 @@ -300,6 +301,8 @@ static u64 power9_bhrb_filter_map(u64 branch_sample_type) static void power9_config_bhrb(u64 pmu_bhrb_filter) { + pmu_bhrb_filter &= POWER9_MMCRA_BHRB_MASK; + /* Enable BHRB filter in PMU */ mtspr(SPRN_MMCRA, (mfspr(SPRN_MMCRA) | pmu_bhrb_filter)); }
Consider a scenario where user creates two events: 1st event: attr.sample_type |= PERF_SAMPLE_BRANCH_STACK; attr.branch_sample_type = PERF_SAMPLE_BRANCH_ANY; fd = perf_event_open(attr, 0, 1, -1, 0); This sets cpuhw->bhrb_filter to 0 and returns valid fd. 2nd event: attr.sample_type |= PERF_SAMPLE_BRANCH_STACK; attr.branch_sample_type = PERF_SAMPLE_BRANCH_CALL; fd = perf_event_open(attr, 0, 1, -1, 0); It overrides cpuhw->bhrb_filter to -1 and returns with error. Now if power_pmu_enable() gets called by any path other than power_pmu_add(), ppmu->config_bhrb(-1) will set mmcra to -1. Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> --- arch/powerpc/perf/core-book3s.c | 6 ++++-- arch/powerpc/perf/power8-pmu.c | 3 +++ arch/powerpc/perf/power9-pmu.c | 3 +++ 3 files changed, 10 insertions(+), 2 deletions(-)