diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2022-04-15 21:20:04 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2022-04-27 20:22:19 +0200 |
| commit | f3eca381bd49d708073ba1a9af4fa6ea5d5810a6 (patch) | |
| tree | f5ab8f6ff5babeaa6edb0b6f9dd74d41fe21fa33 /arch/x86/kernel/cpu/proc.c | |
| parent | 7d84c1ebf9ddafca27b481e6da7d24a023dacaa2 (diff) | |
x86/aperfmperf: Replace arch_freq_get_on_cpu()
Reading the current CPU frequency from /sys/..../scaling_cur_freq involves
in the worst case two IPIs due to the ad hoc sampling.
The frequency invariance infrastructure provides the APERF/MPERF samples
already. Utilize them and consolidate this with the /proc/cpuinfo readout.
The sample is considered valid for 20ms. So for idle or isolated NOHZ full
CPUs the function returns 0, which is matching the previous behaviour.
The resulting text size vs. the original APERF/MPERF plus the separate
frequency invariance code:
text: 2411 -> 723
init.text: 0 -> 767
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20220415161206.934040006@linutronix.de
Diffstat (limited to 'arch/x86/kernel/cpu/proc.c')
| -rw-r--r-- | arch/x86/kernel/cpu/proc.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kernel/cpu/proc.c b/arch/x86/kernel/cpu/proc.c index 4eec8889b0ff..0a0ee55830c7 100644 --- a/arch/x86/kernel/cpu/proc.c +++ b/arch/x86/kernel/cpu/proc.c @@ -84,7 +84,7 @@ static int show_cpuinfo(struct seq_file *m, void *v) seq_printf(m, "microcode\t: 0x%x\n", c->microcode); if (cpu_has(c, X86_FEATURE_TSC)) { - unsigned int freq = aperfmperf_get_khz(cpu); + unsigned int freq = arch_freq_get_on_cpu(cpu); if (!freq) freq = cpufreq_quick_get(cpu); |