From: Kim Phillips kim.phillips@amd.com
Commit d7cbbe49a930 ("perf/x86/amd/uncore: Set ThreadMask and SliceMask for L3 Cache perf events") enables L3 PMC events for all threads and slices by writing 1s in ChL3PmcCfg (L3 PMC PERF_CTL) register fields.
Those bitfields overlap with high order event select bits in the Data Fabric PMC control register, however.
So when a user requests raw Data Fabric events (-e amd_df/event=0xYYY/), the two highest order bits get inadvertently set, changing the counter select to events that don't exist, and for which no counts are read.
This patch changes the logic to write the L3 masks only when dealing with L3 PMC counters.
AMD Family 16h and below Northbridge (NB) counters were not affected.
Signed-off-by: Kim Phillips kim.phillips@amd.com Cc: stable@vger.kernel.org # v4.19+ Cc: Peter Zijlstra peterz@infradead.org Cc: Ingo Molnar mingo@redhat.com Cc: Arnaldo Carvalho de Melo acme@kernel.org Cc: Alexander Shishkin alexander.shishkin@linux.intel.com Cc: Jiri Olsa jolsa@redhat.com Cc: Namhyung Kim namhyung@kernel.org Cc: Thomas Gleixner tglx@linutronix.de Cc: Borislav Petkov bp@alien8.de Cc: "H. Peter Anvin" hpa@zytor.com Cc: Martin Liška mliska@suse.cz Cc: Suravee Suthikulpanit Suravee.Suthikulpanit@amd.com Cc: Janakarajan Natarajan Janakarajan.Natarajan@amd.com Cc: Gary Hook Gary.Hook@amd.com Cc: Pu Wen puwen@hygon.cn Cc: Stephane Eranian eranian@google.com Cc: Vince Weaver vincent.weaver@maine.edu Cc: x86@kernel.org Fixes: d7cbbe49a930 ("perf/x86/amd/uncore: Set ThreadMask and SliceMask for L3 Cache perf events") --- arch/x86/events/amd/uncore.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/events/amd/uncore.c b/arch/x86/events/amd/uncore.c index 79cfd3b30ceb..a8dc2635a719 100644 --- a/arch/x86/events/amd/uncore.c +++ b/arch/x86/events/amd/uncore.c @@ -209,7 +209,7 @@ static int amd_uncore_event_init(struct perf_event *event) * SliceMask and ThreadMask need to be set for certain L3 events in * Family 17h. For other events, the two fields do not affect the count. */ - if (l3_mask) + if (l3_mask && is_llc_event(event)) hwc->config |= (AMD64_L3_SLICE_MASK | AMD64_L3_THREAD_MASK);
if (event->cpu < 0)