diff options
| author | Sandipan Das <[email protected]> | 2024-01-29 11:06:26 +0000 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2024-03-13 10:01:30 +0000 |
| commit | ad8c91282c95f801c37812d59d2d9eba6899b384 (patch) | |
| tree | db3ff37ae380c55be2f6d567dcf669ad694775af | |
| parent | perf/x86/amd/lbr: Discard erroneous branch entries (diff) | |
| download | kernel-ad8c91282c95f801c37812d59d2d9eba6899b384.tar.gz kernel-ad8c91282c95f801c37812d59d2d9eba6899b384.zip | |
perf/x86/amd/core: Avoid register reset when CPU is dead
When bringing a CPU online, some of the PMC and LBR related registers
are reset. The same is done when a CPU is taken offline although that
is unnecessary. This currently happens in the "cpu_dead" callback which
is also incorrect as the callback runs on a control CPU instead of the
one that is being taken offline. This also affects hibernation and
suspend to RAM on some platforms as reported in the link below.
Fixes: 21d59e3e2c40 ("perf/x86/amd/core: Detect PerfMonV2 support")
Reported-by: Mario Limonciello <[email protected]>
Signed-off-by: Sandipan Das <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: https://lore.kernel.org/r/550a026764342cf7e5812680e3e2b91fe662b5ac.1706526029.git.sandipan.das@amd.com
| -rw-r--r-- | arch/x86/events/amd/core.c | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/arch/x86/events/amd/core.c b/arch/x86/events/amd/core.c index 69a3b02e50bb..aec16e581f5b 100644 --- a/arch/x86/events/amd/core.c +++ b/arch/x86/events/amd/core.c @@ -604,7 +604,6 @@ static void amd_pmu_cpu_dead(int cpu) kfree(cpuhw->lbr_sel); cpuhw->lbr_sel = NULL; - amd_pmu_cpu_reset(cpu); if (!x86_pmu.amd_nb_constraints) return; |