Re: [PATCH v5 03/12] perf util: Extend rbtree to support shadow stats

From: Arnaldo Carvalho de Melo
Date: Fri Dec 01 2017 - 09:10:19 EST


Em Fri, Dec 01, 2017 at 06:57:27PM +0800, Jin Yao escreveu:
> Previously the rbtree was used to link generic metrics.

Try to make the one line subject more descriptive, I'm changing it to:

perf stat: Extend rbtree to support per-thread shadow stats

- Arnaldo

> This patches adds new ctx/type/stat into rbtree keys because we
> will use this rbtree to maintain shadow metrics to replace original
> a couple of static arrays for supporting per-thread shadow stats.
>
> Signed-off-by: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
> ---
> tools/perf/util/stat-shadow.c | 27 +++++++++++++++++++++++++++
> 1 file changed, 27 insertions(+)
>
> diff --git a/tools/perf/util/stat-shadow.c b/tools/perf/util/stat-shadow.c
> index 5853901..c53b80d 100644
> --- a/tools/perf/util/stat-shadow.c
> +++ b/tools/perf/util/stat-shadow.c
> @@ -45,7 +45,10 @@ struct stats walltime_nsecs_stats;
> struct saved_value {
> struct rb_node rb_node;
> struct perf_evsel *evsel;
> + enum stat_type type;
> + int ctx;
> int cpu;
> + struct runtime_stat *stat;
> struct stats stats;
> };
>
> @@ -58,6 +61,30 @@ static int saved_value_cmp(struct rb_node *rb_node, const void *entry)
>
> if (a->cpu != b->cpu)
> return a->cpu - b->cpu;
> +
> + /*
> + * Previously the rbtree was used to link generic metrics.
> + * The keys were evsel/cpu. Now the rbtree is extended to support
> + * per-thread shadow stats. For shadow stats case, the keys
> + * are cpu/type/ctx/stat (evsel is NULL). For generic metrics
> + * case, the keys are still evsel/cpu (type/ctx/stat are 0 or NULL).
> + */
> + if (a->type != b->type)
> + return a->type - b->type;
> +
> + if (a->ctx != b->ctx)
> + return a->ctx - b->ctx;
> +
> + if (a->evsel == NULL && b->evsel == NULL) {
> + if (a->stat == b->stat)
> + return 0;
> +
> + if ((char *)a->stat < (char *)b->stat)
> + return -1;
> +
> + return 1;
> + }
> +
> if (a->evsel == b->evsel)
> return 0;
> if ((char *)a->evsel < (char *)b->evsel)
> --
> 2.7.4