From: Kim Phillips <[email protected]>
commit 16f4641166b10e199f0d7b68c2c5f004fef0bda3 upstream.
The following 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 1's 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 <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Gary Hook <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Janakarajan Natarajan <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Martin Liska <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Pu Wen <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Suravee Suthikulpanit <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Vince Weaver <[email protected]>
Fixes: d7cbbe49a930 ("perf/x86/amd/uncore: Set ThreadMask and SliceMask for L3
Cache perf events")
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
arch/x86/events/amd/uncore.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/x86/events/amd/uncore.c
+++ b/arch/x86/events/amd/uncore.c
@@ -214,7 +214,7 @@ static int amd_uncore_event_init(struct
* 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)
