| Message ID | 20220415161206.817702355@linutronix.de (mailing list archive) |
|---|---|
| State | Handled Elsewhere, archived |
| Headers | show |
| Series | x86/cpu: Consolidate APERF/MPERF code | expand |
On Fri, Apr 15, 2022 at 9:20 PM Thomas Gleixner <tglx@linutronix.de> wrote: > > 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@linutronix.de> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > --- > arch/x86/kernel/cpu/aperfmperf.c | 14 +++++++++++++- > 1 file changed, 13 insertions(+), 1 deletion(-) > > --- 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); > } > >
--- 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); }
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@linutronix.de> --- arch/x86/kernel/cpu/aperfmperf.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-)