Commit e7fcc545 authored by Dapeng Mi's avatar Dapeng Mi Committed by Peter Zijlstra
Browse files

perf/x86/intel: Fix OMR snoop information parsing issues 

When omr_source is 0x2, the omr_snoop (bit[6]) and omr_promoted (bit[7])
fields are combined to represent the snoop information. However, the
omr_promoted field was not left-shifted by 1 bit, resulting in incorrect
snoop information.

Besides, the snoop information parsing is not accurate for some OMR
sources, like the snoop information should be SNOOP_NONE for these memory
access (omr_source >= 7) instead of SNOOP_HIT.

Fix these issues.

Closes: https://lore.kernel.org/all/CAP-5=fW4zLWFw1v38zCzB9-cseNSTTCtup=p2SDxZq7dPayVww@mail.gmail.com/


Fixes: d2bdcde9 ("perf/x86/intel: Add support for PEBS memory auxiliary info field in DMR")
Reported-by: default avatarIan Rogers <irogers@google.com>
Signed-off-by: default avatarDapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: default avatarIan Rogers <irogers@google.com>
Link: https://patch.msgid.link/20260311075201.2951073-1-dapeng1.mi@linux.intel.com
parent 1d07bbd7

arch/x86/events/intel/ds.c

+7 −4
Original line number Diff line number Diff line
@@ -345,12 +345,12 @@ static u64 parse_omr_data_source(u8 dse) 
	if (omr.omr_remote)

		val |= REM;



	val |= omr.omr_hitm ? P(SNOOP, HITM) : P(SNOOP, HIT);



	if (omr.omr_source == 0x2) {

		u8 snoop = omr.omr_snoop | omr.omr_promoted;

		u8 snoop = omr.omr_snoop | (omr.omr_promoted << 1);



		if (snoop == 0x0)

		if (omr.omr_hitm)

			val |= P(SNOOP, HITM);

		else if (snoop == 0x0)

			val |= P(SNOOP, NA);

		else if (snoop == 0x1)

			val |= P(SNOOP, MISS);
@@ -359,7 +359,10 @@ static u64 parse_omr_data_source(u8 dse) 
		else if (snoop == 0x3)

			val |= P(SNOOP, NONE);

	} else if (omr.omr_source > 0x2 && omr.omr_source < 0x7) {

		val |= omr.omr_hitm ? P(SNOOP, HITM) : P(SNOOP, HIT);

		val |= omr.omr_snoop ? P(SNOOPX, FWD) : 0;

	} else {

		val |= P(SNOOP, NONE);

	}



	return val;