perf/x86/intel: Fix instructions:ppp support in Sapphire Rapids
authorKan Liang <kan.liang@linux.intel.com>
Fri, 18 Jun 2021 15:12:54 +0000 (08:12 -0700)
committerPeter Zijlstra <peterz@infradead.org>
Wed, 23 Jun 2021 16:30:55 +0000 (18:30 +0200)
Perf errors out when sampling instructions:ppp.

$ perf record -e instructions:ppp -- true
Error:
The sys_perf_event_open() syscall returned with 22 (Invalid argument)
for event (instructions:ppp).

The instruction PDIR is only available on the fixed counter 0. The event
constraint has been updated to fixed0_constraint in
icl_get_event_constraints(). The Sapphire Rapids codes unconditionally
error out for the event which is not available on the GP counter 0.

Make the instructions:ppp an exception.

Fixes: 61b985e3e775 ("perf/x86/intel: Add perf core PMU support for Sapphire Rapids")
Reported-by: Yasin, Ahmad <ahmad.yasin@intel.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/1624029174-122219-4-git-send-email-kan.liang@linux.intel.com
arch/x86/events/intel/core.c

index e442b5542edd6bd9f86805c0e4fe4728549af9f3..e355db5da09736aba44c985ba47adf0bf2e08677 100644 (file)
@@ -4032,8 +4032,10 @@ spr_get_event_constraints(struct cpu_hw_events *cpuc, int idx,
         * The :ppp indicates the Precise Distribution (PDist) facility, which
         * is only supported on the GP counter 0. If a :ppp event which is not
         * available on the GP counter 0, error out.
+        * Exception: Instruction PDIR is only available on the fixed counter 0.
         */
-       if (event->attr.precise_ip == 3) {
+       if ((event->attr.precise_ip == 3) &&
+           !constraint_match(&fixed0_constraint, event->hw.config)) {
                if (c->idxmsk64 & BIT_ULL(0))
                        return &counter0_constraint;