| Message ID | 1483434793-1814-1-git-send-email-maddy@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
Madhavan Srinivasan <maddy@linux.vnet.ibm.com> writes: > "use_siar" variable is primarily used for deciding the sampled address > and the privilege level to be reported for a sample. perf_read_regs() > function updates the "use_siar" and "regs->result" based on the pmu > flags along with other checks. To force the use of MSR to report the > privilege level and to use "regs->nip" to report the instruction pointer, > set "PPMU_NO_CONT_SAMPLING" flag and remove "PPMU_HAS_SIER" from the > ppmu->flags. This still won't work for marked events AFAICS: if (TRAP(regs) != 0xf00) use_siar = 0; else if (marked) use_siar = 1; else if ((ppmu->flags & PPMU_NO_CONT_SAMPLING)) use_siar = 0; else if (!(ppmu->flags & PPMU_NO_SIPR) && regs_sipr(regs)) use_siar = 0; else use_siar = 1; So perhaps we just want a USE_SIAR flag? And I don't see how HAS_SIER is related? Or is SIER broken too? cheers
On Tuesday 17 January 2017 11:16 AM, Michael Ellerman wrote: > Madhavan Srinivasan <maddy@linux.vnet.ibm.com> writes: > >> "use_siar" variable is primarily used for deciding the sampled address >> and the privilege level to be reported for a sample. perf_read_regs() >> function updates the "use_siar" and "regs->result" based on the pmu >> flags along with other checks. To force the use of MSR to report the >> privilege level and to use "regs->nip" to report the instruction pointer, >> set "PPMU_NO_CONT_SAMPLING" flag and remove "PPMU_HAS_SIER" from the >> ppmu->flags. > This still won't work for marked events AFAICS: nice catch. My bad. Did not try with the marked events when testing this patch. > > if (TRAP(regs) != 0xf00) > use_siar = 0; > else if (marked) > use_siar = 1; > else if ((ppmu->flags & PPMU_NO_CONT_SAMPLING)) > use_siar = 0; > else if (!(ppmu->flags & PPMU_NO_SIPR) && regs_sipr(regs)) > use_siar = 0; > else > use_siar = 1; > > So perhaps we just want a USE_SIAR flag? OK, Will add a new flag. How about "PPMU_DISBALE_USE_SIAR"? > And I don't see how HAS_SIER is related? Or is SIER broken too? We dont see proper values in SIER for some samples and we use SIER (regs_sipr) to update the misc_flag. Will fix the commit message. Maddy > cheers >
diff --git a/arch/powerpc/perf/power9-pmu.c b/arch/powerpc/perf/power9-pmu.c index a46ef29e50e7..06b7e8ebd29a 100644 --- a/arch/powerpc/perf/power9-pmu.c +++ b/arch/powerpc/perf/power9-pmu.c @@ -403,7 +403,7 @@ static struct power_pmu power9_isa207_pmu = { .bhrb_filter_map = power9_bhrb_filter_map, .get_constraint = isa207_get_constraint, .disable_pmc = isa207_disable_pmc, - .flags = PPMU_HAS_SIER | PPMU_ARCH_207S, + .flags = PPMU_NO_CONT_SAMPLING | PPMU_ARCH_207S, .n_generic = ARRAY_SIZE(power9_generic_events), .generic_events = power9_generic_events, .cache_events = &power9_cache_events,
"use_siar" variable is primarily used for deciding the sampled address and the privilege level to be reported for a sample. perf_read_regs() function updates the "use_siar" and "regs->result" based on the pmu flags along with other checks. To force the use of MSR to report the privilege level and to use "regs->nip" to report the instruction pointer, set "PPMU_NO_CONT_SAMPLING" flag and remove "PPMU_HAS_SIER" from the ppmu->flags. Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> --- arch/powerpc/perf/power9-pmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)