Re: [PATCH] Perf stat: Fix the ratio comments of miss-events

From: Arnaldo Carvalho de Melo
Date: Tue Nov 19 2019 - 10:59:44 EST


Em Sat, Nov 16, 2019 at 03:48:41PM +0800, lqqq341 escreveu:
> From: Qi Liu <liuqi115@xxxxxxxxxxxxx>
>
> Perf stat displays miss ratio of L1-dcache, L1-icache, dTLB cache,
> iTLB cache and LL-cache. Take L1-dcache for example, its miss ratio
> is caculated as "L1-dcache-load-misses/L1-dcache-loads". So "of all
> L1-dcache hits" is unsuitable to describe it, and "of all L1-dcache
> accesses" seems better. The comments of L1-icache, dTLB cache, iTLB
> cache and LL-cache are fixed in the same way.
>
> Signed-off-by: Qi Liu <liuqi115@xxxxxxxxxxxxx>
> ---
> tools/perf/util/stat-shadow.c | 30 ++++++++++++++++++++----------
> 1 file changed, 20 insertions(+), 10 deletions(-)
>
> diff --git a/tools/perf/util/stat-shadow.c b/tools/perf/util/stat-shadow.c
> index 2c41d47..a3bdf2b 100644
> --- a/tools/perf/util/stat-shadow.c
> +++ b/tools/perf/util/stat-shadow.c
> @@ -506,7 +506,8 @@ static void print_l1_dcache_misses(struct perf_stat_config *config,
>
> color = get_ratio_color(GRC_CACHE_MISSES, ratio);
>
> - out->print_metric(config, out->ctx, color, "%7.2f%%", "of all L1-dcache hits", ratio);
> + out->print_metric(config, out->ctx, color, "%7.2f%%",
> + "of all L1-dcache accesses", ratio);


Why have you reflowed all those lines? This patch should have been like:

- out->print_metric(config, out->ctx, color, "%7.2f%%", "of all L1-dcache hits", ratio);
+ out->print_metric(config, out->ctx, color, "%7.2f%%", "of all L1-dcache accesses", ratio);

Notice how it is easier to compare the changes, and also to keep the
flowing like it was before your change,

Thanks,

- Arnaldo

> }
>
> static void print_l1_icache_misses(struct perf_stat_config *config,
> @@ -527,7 +528,8 @@ static void print_l1_icache_misses(struct perf_stat_config *config,
> ratio = avg / total * 100.0;
>
> color = get_ratio_color(GRC_CACHE_MISSES, ratio);
> - out->print_metric(config, out->ctx, color, "%7.2f%%", "of all L1-icache hits", ratio);
> + out->print_metric(config, out->ctx, color, "%7.2f%%",
> + "of all L1-icache accesses", ratio);
> }
>
> static void print_dtlb_cache_misses(struct perf_stat_config *config,
> @@ -547,7 +549,8 @@ static void print_dtlb_cache_misses(struct perf_stat_config *config,
> ratio = avg / total * 100.0;
>
> color = get_ratio_color(GRC_CACHE_MISSES, ratio);
> - out->print_metric(config, out->ctx, color, "%7.2f%%", "of all dTLB cache hits", ratio);
> + out->print_metric(config, out->ctx, color, "%7.2f%%",
> + "of all dTLB cache accesses", ratio);
> }
>
> static void print_itlb_cache_misses(struct perf_stat_config *config,
> @@ -567,7 +570,8 @@ static void print_itlb_cache_misses(struct perf_stat_config *config,
> ratio = avg / total * 100.0;
>
> color = get_ratio_color(GRC_CACHE_MISSES, ratio);
> - out->print_metric(config, out->ctx, color, "%7.2f%%", "of all iTLB cache hits", ratio);
> + out->print_metric(config, out->ctx, color, "%7.2f%%",
> + "of all iTLB cache accesses", ratio);
> }
>
> static void print_ll_cache_misses(struct perf_stat_config *config,
> @@ -587,7 +591,8 @@ static void print_ll_cache_misses(struct perf_stat_config *config,
> ratio = avg / total * 100.0;
>
> color = get_ratio_color(GRC_CACHE_MISSES, ratio);
> - out->print_metric(config, out->ctx, color, "%7.2f%%", "of all LL-cache hits", ratio);
> + out->print_metric(config, out->ctx, color, "%7.2f%%",
> + "of all LL-cache accesses", ratio);
> }
>
> /*
> @@ -872,7 +877,8 @@ void perf_stat__print_shadow_stats(struct perf_stat_config *config,
> if (runtime_stat_n(st, STAT_L1_DCACHE, ctx, cpu) != 0)
> print_l1_dcache_misses(config, cpu, evsel, avg, out, st);
> else
> - print_metric(config, ctxp, NULL, NULL, "of all L1-dcache hits", 0);
> + print_metric(config, ctxp, NULL, NULL,
> + "of all L1-dcache accesses", 0);
> } else if (
> evsel->core.attr.type == PERF_TYPE_HW_CACHE &&
> evsel->core.attr.config == ( PERF_COUNT_HW_CACHE_L1I |
> @@ -882,7 +888,8 @@ void perf_stat__print_shadow_stats(struct perf_stat_config *config,
> if (runtime_stat_n(st, STAT_L1_ICACHE, ctx, cpu) != 0)
> print_l1_icache_misses(config, cpu, evsel, avg, out, st);
> else
> - print_metric(config, ctxp, NULL, NULL, "of all L1-icache hits", 0);
> + print_metric(config, ctxp, NULL, NULL,
> + "of all L1-icache accesses", 0);
> } else if (
> evsel->core.attr.type == PERF_TYPE_HW_CACHE &&
> evsel->core.attr.config == ( PERF_COUNT_HW_CACHE_DTLB |
> @@ -892,7 +899,8 @@ void perf_stat__print_shadow_stats(struct perf_stat_config *config,
> if (runtime_stat_n(st, STAT_DTLB_CACHE, ctx, cpu) != 0)
> print_dtlb_cache_misses(config, cpu, evsel, avg, out, st);
> else
> - print_metric(config, ctxp, NULL, NULL, "of all dTLB cache hits", 0);
> + print_metric(config, ctxp, NULL, NULL,
> + "of all dTLB cache accesses", 0);
> } else if (
> evsel->core.attr.type == PERF_TYPE_HW_CACHE &&
> evsel->core.attr.config == ( PERF_COUNT_HW_CACHE_ITLB |
> @@ -902,7 +910,8 @@ void perf_stat__print_shadow_stats(struct perf_stat_config *config,
> if (runtime_stat_n(st, STAT_ITLB_CACHE, ctx, cpu) != 0)
> print_itlb_cache_misses(config, cpu, evsel, avg, out, st);
> else
> - print_metric(config, ctxp, NULL, NULL, "of all iTLB cache hits", 0);
> + print_metric(config, ctxp, NULL, NULL,
> + "of all iTLB cache accesses", 0);
> } else if (
> evsel->core.attr.type == PERF_TYPE_HW_CACHE &&
> evsel->core.attr.config == ( PERF_COUNT_HW_CACHE_LL |
> @@ -912,7 +921,8 @@ void perf_stat__print_shadow_stats(struct perf_stat_config *config,
> if (runtime_stat_n(st, STAT_LL_CACHE, ctx, cpu) != 0)
> print_ll_cache_misses(config, cpu, evsel, avg, out, st);
> else
> - print_metric(config, ctxp, NULL, NULL, "of all LL-cache hits", 0);
> + print_metric(config, ctxp, NULL, NULL,
> + "of all LL-cache accesses", 0);
> } else if (perf_evsel__match(evsel, HARDWARE, HW_CACHE_MISSES)) {
> total = runtime_stat_avg(st, STAT_CACHEREFS, ctx, cpu);
>
> --
> 2.8.1

--

- Arnaldo