From: Xiao Guangrong <xiaoguangrong@xxxxxxxxxxxxxxxxxx> Then, the code can be shared between kvm events and perf stat. Signed-off-by: Xiao Guangrong <xiaoguangrong@xxxxxxxxxxxxxxxxxx> [ Dong Hao <haodong@xxxxxxxxxxxxxxxxxx>: rebase it on acme's git tree ] Signed-off-by: Dong Hao <haodong@xxxxxxxxxxxxxxxxxx> Cc: Avi Kivity <avi@xxxxxxxxxx> Cc: David Ahern <dsahern@xxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: kvm@xxxxxxxxxxxxxxx Cc: Marcelo Tosatti <mtosatti@xxxxxxxxxx> Cc: Runzhen Wang <runzhen@xxxxxxxxxxxxxxxxxx> Cc: Xiao Guangrong <xiaoguangrong@xxxxxxxxxxxxxxxxxx Link: http://lkml.kernel.org/r/1347870675-31495-3-git-send-email-haodong@xxxxxxxxxxxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> --- tools/perf/Makefile | 1 + tools/perf/builtin-stat.c | 56 +------------------------------------------ tools/perf/util/stat.c | 57 +++++++++++++++++++++++++++++++++++++++++++++ tools/perf/util/stat.h | 16 ++++++++++++ 4 files changed, 76 insertions(+), 54 deletions(-) create mode 100644 tools/perf/util/stat.c create mode 100644 tools/perf/util/stat.h diff --git a/tools/perf/Makefile b/tools/perf/Makefile index 209774b..5077f8e 100644 --- a/tools/perf/Makefile +++ b/tools/perf/Makefile @@ -406,6 +406,7 @@ LIB_OBJS += $(OUTPUT)util/target.o LIB_OBJS += $(OUTPUT)util/rblist.o LIB_OBJS += $(OUTPUT)util/intlist.o LIB_OBJS += $(OUTPUT)util/vdso.o +LIB_OBJS += $(OUTPUT)util/stat.o LIB_OBJS += $(OUTPUT)ui/helpline.o LIB_OBJS += $(OUTPUT)ui/hist.o diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c index dab347d..3c43a35 100644 --- a/tools/perf/builtin-stat.c +++ b/tools/perf/builtin-stat.c @@ -51,13 +51,13 @@ #include "util/evsel.h" #include "util/debug.h" #include "util/color.h" +#include "util/stat.h" #include "util/header.h" #include "util/cpumap.h" #include "util/thread.h" #include "util/thread_map.h" #include <sys/prctl.h> -#include <math.h> #include <locale.h> #define DEFAULT_SEPARATOR " " @@ -199,11 +199,6 @@ static int output_fd; static volatile int done = 0; -struct stats -{ - double n, mean, M2; -}; - struct perf_stat { struct stats res_stats[3]; }; @@ -220,50 +215,6 @@ static void perf_evsel__free_stat_priv(struct perf_evsel *evsel) evsel->priv = NULL; } -static void update_stats(struct stats *stats, u64 val) -{ - double delta; - - stats->n++; - delta = val - stats->mean; - stats->mean += delta / stats->n; - stats->M2 += delta*(val - stats->mean); -} - -static double avg_stats(struct stats *stats) -{ - return stats->mean; -} - -/* - * http://en.wikipedia.org/wiki/Algorithms_for_calculating_variance - * - * (\Sum n_i^2) - ((\Sum n_i)^2)/n - * s^2 = ------------------------------- - * n - 1 - * - * http://en.wikipedia.org/wiki/Stddev - * - * The std dev of the mean is related to the std dev by: - * - * s - * s_mean = ------- - * sqrt(n) - * - */ -static double stddev_stats(struct stats *stats) -{ - double variance, variance_mean; - - if (!stats->n) - return 0.0; - - variance = stats->M2 / (stats->n - 1); - variance_mean = variance / stats->n; - - return sqrt(variance_mean); -} - static struct stats runtime_nsecs_stats[MAX_NR_CPUS]; static struct stats runtime_cycles_stats[MAX_NR_CPUS]; static struct stats runtime_stalled_cycles_front_stats[MAX_NR_CPUS]; @@ -559,10 +510,7 @@ static int run_perf_stat(int argc __maybe_unused, const char **argv) static void print_noise_pct(double total, double avg) { - double pct = 0.0; - - if (avg) - pct = 100.0*total/avg; + double pct = rel_stddev_stats(total, avg); if (csv_output) fprintf(output, "%s%.2f%%", csv_sep, pct); diff --git a/tools/perf/util/stat.c b/tools/perf/util/stat.c new file mode 100644 index 0000000..2374212 --- /dev/null +++ b/tools/perf/util/stat.c @@ -0,0 +1,57 @@ +#include <math.h> + +#include "stat.h" + +void update_stats(struct stats *stats, u64 val) +{ + double delta; + + stats->n++; + delta = val - stats->mean; + stats->mean += delta / stats->n; + stats->M2 += delta*(val - stats->mean); +} + +double avg_stats(struct stats *stats) +{ + return stats->mean; +} + +/* + * http://en.wikipedia.org/wiki/Algorithms_for_calculating_variance + * + * (\Sum n_i^2) - ((\Sum n_i)^2)/n + * s^2 = ------------------------------- + * n - 1 + * + * http://en.wikipedia.org/wiki/Stddev + * + * The std dev of the mean is related to the std dev by: + * + * s + * s_mean = ------- + * sqrt(n) + * + */ +double stddev_stats(struct stats *stats) +{ + double variance, variance_mean; + + if (!stats->n) + return 0.0; + + variance = stats->M2 / (stats->n - 1); + variance_mean = variance / stats->n; + + return sqrt(variance_mean); +} + +double rel_stddev_stats(double stddev, double avg) +{ + double pct = 0.0; + + if (avg) + pct = 100.0 * stddev/avg; + + return pct; +} diff --git a/tools/perf/util/stat.h b/tools/perf/util/stat.h new file mode 100644 index 0000000..588367c --- /dev/null +++ b/tools/perf/util/stat.h @@ -0,0 +1,16 @@ +#ifndef __PERF_STATS_H +#define __PERF_STATS_H + +#include "types.h" + +struct stats +{ + double n, mean, M2; +}; + +void update_stats(struct stats *stats, u64 val); +double avg_stats(struct stats *stats); +double stddev_stats(struct stats *stats); +double rel_stddev_stats(double stddev, double avg); + +#endif -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
