On Jul 26, 2015 9:31 AM, "Jiri Olsa" <[email protected]> wrote: > > On Mon, Jul 20, 2015 at 11:49:06AM -0400, Kan Liang wrote: > > From: Andy Lutomirski <[email protected]> > > > > This patch adds freq PMU to support time and freq related counters > > includes TSC, IA32_APERF, IA32_MPERF and IA32_PPERF. > > > > The events are exposed in sysfs for use by perf stat and other tools. > > The files are under /sys/devices/freq/events/ > > > > These events only support system-wide mode counting. > > > > The PMU type (attr->type) is PERF_TYPE_FREQ. > > > > Example: > > > > To caculate the CPU% > > CPU_Utilization = CPU_CLK_UNHALTED.REF_TSC / TSC > > > > $ perf stat -e '{ref-cycles,freq/tsc/}' -C0 -- taskset -c 0 sleep 1 > > 3164023,,ref-cycles,1048387386,100.00 > > 2410812089,,freq/tsc/,1050022373,100.00 > > The CPU% for sleep is 0.13%. > > > > $ perf stat -e '{ref-cycles,freq/tsc/}' -C0 -- taskset -c 0 busyloop > > 15662183572,,ref-cycles,6822637855,100.00 > > 15667608992,,freq/tsc/,6823978523,100.00 > > The CPU% for busy loop is 99.9%. > > > > Signed-off-by: Andy Lutomirski <[email protected]> > > Signed-off-by: Kan Liang <[email protected]> > > SNIP > > > diff --git a/arch/x86/kernel/cpu/perf_event_freq.c > > b/arch/x86/kernel/cpu/perf_event_freq.c > > new file mode 100644 > > index 0000000..9389b3b > > --- /dev/null > > +++ b/arch/x86/kernel/cpu/perf_event_freq.c > > @@ -0,0 +1,207 @@ > > +#include <linux/perf_event.h> > > + > > +enum perf_freq_id { > > + /* > > + * freq events, generalized by the kernel: > > + */ > > + PERF_FREQ_TSC = 0, > > + PERF_FREQ_APERF = 1, > > + PERF_FREQ_MPERF = 2, > > + PERF_FREQ_PPERF = 3, > > + > > + PERF_FREQ_EVENT_MAX, /* non-ABI */ > > should this be in uapi header?
Possibly not, since user code can fish them out of sysfs. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
