diff options
Diffstat (limited to 'arch/x86/events/core.c')
| -rw-r--r-- | arch/x86/events/core.c | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index 6e3f0c18908e..9a89d98c55bd 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -49,6 +49,7 @@ DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events) = { .enabled = 1, }; +DEFINE_STATIC_KEY_FALSE(rdpmc_never_available_key); DEFINE_STATIC_KEY_FALSE(rdpmc_always_available_key); u64 __read_mostly hw_cache_event_ids @@ -2181,21 +2182,26 @@ static ssize_t set_attr_rdpmc(struct device *cdev, if (x86_pmu.attr_rdpmc_broken) return -ENOTSUPP; - if ((val == 2) != (x86_pmu.attr_rdpmc == 2)) { + if (val != x86_pmu.attr_rdpmc) { /* - * Changing into or out of always available, aka - * perf-event-bypassing mode. This path is extremely slow, + * Changing into or out of never available or always available, + * aka perf-event-bypassing mode. This path is extremely slow, * but only root can trigger it, so it's okay. */ + if (val == 0) + static_branch_inc(&rdpmc_never_available_key); + else if (x86_pmu.attr_rdpmc == 0) + static_branch_dec(&rdpmc_never_available_key); + if (val == 2) static_branch_inc(&rdpmc_always_available_key); - else + else if (x86_pmu.attr_rdpmc == 2) static_branch_dec(&rdpmc_always_available_key); + on_each_cpu(refresh_pce, NULL, 1); + x86_pmu.attr_rdpmc = val; } - x86_pmu.attr_rdpmc = val; - return count; } |