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perf/x86/intel: Fix bug for "cycles:p" and "cycles:pp" on SLM
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cycles:p and cycles:pp do not work on SLM since commit:

   86a0446 ("perf/x86: Revamp PEBS event selection")

UOPS_RETIRED.ALL is not a PEBS capable event, so it should not be used
to count cycle number.

Actually SLM calls intel_pebs_aliases_core2() which uses INST_RETIRED.ANY_P
to count the number of cycles. It's a PEBS capable event. But inv and
cmask must be set to count cycles.

Considering SLM allows all events as PEBS with no flags, only
INST_RETIRED.ANY_P, inv=1, cmask=16 needs to handled specially.

Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1421084541-31639-1-git-send-email-kan.liang@intel.com
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Kan Liang authored and Ingo Molnar committed Jan 16, 2015
1 parent 433678b commit 3363673
Showing 1 changed file with 2 additions and 2 deletions.
4 changes: 2 additions & 2 deletions arch/x86/kernel/cpu/perf_event_intel_ds.c
Original file line number Diff line number Diff line change
Expand Up @@ -568,8 +568,8 @@ struct event_constraint intel_atom_pebs_event_constraints[] = {
};

struct event_constraint intel_slm_pebs_event_constraints[] = {
/* UOPS_RETIRED.ALL, inv=1, cmask=16 (cycles:p). */
INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c2, 0xf),
/* INST_RETIRED.ANY_P, inv=1, cmask=16 (cycles:p). */
INTEL_FLAGS_EVENT_CONSTRAINT(0x108000c0, 0x1),
/* Allow all events as PEBS with no flags */
INTEL_ALL_EVENT_CONSTRAINT(0, 0x1),
EVENT_CONSTRAINT_END
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