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perf/x86/vlbr: Add c->flags to vlbr event constraints

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Just like what we do in the x86_get_event_constraints(), the
PERF_X86_EVENT_LBR_SELECT flag should also be propagated
to event->hw.flags so that the host lbr driver can save/restore
MSR_LBR_SELECT for the special vlbr event created by KVM or BPF.

Fixes: 097e4311cda9 ("perf/x86: Add constraint to create guest LBR event without hw counter")
Reported-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Like Xu <likexu@tencent.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Wanpeng Li <wanpengli@tencent.com>
Link: https://lore.kernel.org/r/20211103091716.59906-1-likexu@tencent.com
This commit is contained in:
Like Xu 2021-11-03 17:17:16 +08:00 committed by Peter Zijlstra
parent 0fe39a3929
commit 5863702561
1 changed files with 3 additions and 1 deletions
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4
arch/x86/events/intel/core.c
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@ -3048,8 +3048,10 @@ intel_vlbr_constraints(struct perf_event *event)
{
struct event_constraint *c = &vlbr_constraint;
if (unlikely(constraint_match(c, event->hw.config)))
if (unlikely(constraint_match(c, event->hw.config))) {
event->hw.flags |= c->flags;
return c;
}
return NULL;
}