The following commit has been merged into the x86/cleanups branch of tip: Commit-ID: cd8c0e142daf9de9ce594e61b75509b0af7bfb26 Gitweb: https://git.kernel.org/tip/cd8c0e142daf9de9ce594e61b75509b0af7bfb26 Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx> AuthorDate: Fri, 15 Apr 2022 21:20:01 +02:00 Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx> CommitterDate: Wed, 27 Apr 2022 20:22:19 +02:00 x86/aperfmperf: Store aperf/mperf data for cpu frequency reads Now that the MSR readout is unconditional, store the results in the per CPU data structure along with a jiffies timestamp for the CPU frequency readout code. Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Acked-by: Paul E. McKenney <paulmck@xxxxxxxxxx> Link: https://lore.kernel.org/r/20220415161206.817702355@xxxxxxxxxxxxx --- arch/x86/kernel/cpu/aperfmperf.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/cpu/aperfmperf.c b/arch/x86/kernel/cpu/aperfmperf.c index df528a4..963c069 100644 --- a/arch/x86/kernel/cpu/aperfmperf.c +++ b/arch/x86/kernel/cpu/aperfmperf.c @@ -24,11 +24,17 @@ #include "cpu.h" struct aperfmperf { + seqcount_t seq; + unsigned long last_update; + u64 acnt; + u64 mcnt; u64 aperf; u64 mperf; }; -static DEFINE_PER_CPU_SHARED_ALIGNED(struct aperfmperf, cpu_samples); +static DEFINE_PER_CPU_SHARED_ALIGNED(struct aperfmperf, cpu_samples) = { + .seq = SEQCNT_ZERO(cpu_samples.seq) +}; struct aperfmperf_sample { unsigned int khz; @@ -515,6 +521,12 @@ void arch_scale_freq_tick(void) s->aperf = aperf; s->mperf = mperf; + raw_write_seqcount_begin(&s->seq); + s->last_update = jiffies; + s->acnt = acnt; + s->mcnt = mcnt; + raw_write_seqcount_end(&s->seq); + scale_freq_tick(acnt, mcnt); }
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