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| author | Chris Zankel <chris@zankel.net> | 2015-08-29 23:55:58 (GMT) |
|---|---|---|
| committer | Chris Zankel <chris@zankel.net> | 2015-08-29 23:55:58 (GMT) |
| commit | 650c919798c71fb34b77a6f2ba03a06907f06a76 (patch) | |
| tree | d1c60012d4d86846d25f1d0b783b5122c26a2e31 /arch/x86/kernel/cpu/perf_event_intel_cqm.c | |
| parent | 895fb3159280fe7695b35ec7c87ec19e13ca5b6e (diff) | |
| parent | 64291f7db5bd8150a74ad2036f1037e6a0428df2 (diff) | |
| download | linux-650c919798c71fb34b77a6f2ba03a06907f06a76.tar.xz | |
Merge tag 'v4.2' into for_next
Linux 4.2
Diffstat (limited to 'arch/x86/kernel/cpu/perf_event_intel_cqm.c')
| -rw-r--r-- | arch/x86/kernel/cpu/perf_event_intel_cqm.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/arch/x86/kernel/cpu/perf_event_intel_cqm.c b/arch/x86/kernel/cpu/perf_event_intel_cqm.c index 1880761..377e8f8 100644 --- a/arch/x86/kernel/cpu/perf_event_intel_cqm.c +++ b/arch/x86/kernel/cpu/perf_event_intel_cqm.c @@ -952,6 +952,14 @@ static u64 intel_cqm_event_count(struct perf_event *event) return 0; /* + * Getting up-to-date values requires an SMP IPI which is not + * possible if we're being called in interrupt context. Return + * the cached values instead. + */ + if (unlikely(in_interrupt())) + goto out; + + /* * Notice that we don't perform the reading of an RMID * atomically, because we can't hold a spin lock across the * IPIs. @@ -1247,7 +1255,7 @@ static inline void cqm_pick_event_reader(int cpu) cpumask_set_cpu(cpu, &cqm_cpumask); } -static void intel_cqm_cpu_prepare(unsigned int cpu) +static void intel_cqm_cpu_starting(unsigned int cpu) { struct intel_pqr_state *state = &per_cpu(pqr_state, cpu); struct cpuinfo_x86 *c = &cpu_data(cpu); @@ -1288,13 +1296,11 @@ static int intel_cqm_cpu_notifier(struct notifier_block *nb, unsigned int cpu = (unsigned long)hcpu; switch (action & ~CPU_TASKS_FROZEN) { - case CPU_UP_PREPARE: - intel_cqm_cpu_prepare(cpu); - break; case CPU_DOWN_PREPARE: intel_cqm_cpu_exit(cpu); break; case CPU_STARTING: + intel_cqm_cpu_starting(cpu); cqm_pick_event_reader(cpu); break; } @@ -1365,7 +1371,7 @@ static int __init intel_cqm_init(void) goto out; for_each_online_cpu(i) { - intel_cqm_cpu_prepare(i); + intel_cqm_cpu_starting(i); cqm_pick_event_reader(i); } |