Earlier workaround added by
400816f60c54 ("perf/x86/intel: Implement support for TSX Force Abort")
for perf counter interactions [1] are not required on some client
systems which received a microcode update that deprecates TSX.
Bypass the perf workaround when such microcode is enumerated.
[1] [ bp: Look for document ID 604224, "Performance Monitoring Impact
of Intel Transactional Synchronization Extension Memory". Since
there's no way for us to have stable links to documents... ]
[ bp: Massage comment. ]
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Tested-by: Neelima Krishnan <neelima.krishnan@intel.com>
Link: https://lkml.kernel.org/r/e4d410f786946280ced02dd07c74e0a74f1d10cb.1623704845.git-series.pawan.kumar.gupta@linux.intel.com
tsx_attr = hsw_tsx_events_attrs;
intel_pmu_pebs_data_source_skl(pmem);
- if (boot_cpu_has(X86_FEATURE_TSX_FORCE_ABORT)) {
+ /*
+ * Processors with CPUID.RTM_ALWAYS_ABORT have TSX deprecated by default.
+ * TSX force abort hooks are not required on these systems. Only deploy
+ * workaround when microcode has not enabled X86_FEATURE_RTM_ALWAYS_ABORT.
+ */
+ if (boot_cpu_has(X86_FEATURE_TSX_FORCE_ABORT) &&
+ !boot_cpu_has(X86_FEATURE_RTM_ALWAYS_ABORT)) {
x86_pmu.flags |= PMU_FL_TFA;
x86_pmu.get_event_constraints = tfa_get_event_constraints;
x86_pmu.enable_all = intel_tfa_pmu_enable_all;