linux-kernel - Re: [PATCH 1/3] perf sched timehist: Mark schedule function in callchains

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Date:   Fri, 25 Nov 2016 10:43:24 -0300
From:   Arnaldo Carvalho de Melo <acme@...nel.org>
To:     Namhyung Kim <namhyung@...nel.org>
Cc:     Ingo Molnar <mingo@...nel.org>,
        Peter Zijlstra <a.p.zijlstra@...llo.nl>,
        Jiri Olsa <jolsa@...nel.org>,
        LKML <linux-kernel@...r.kernel.org>,
        David Ahern <dsahern@...il.com>,
        Stephane Eranian <eranian@...gle.com>,
        Andi Kleen <andi@...stfloor.org>
Subject: Re: [PATCH 1/3] perf sched timehist: Mark schedule function in
 callchains

Em Thu, Nov 24, 2016 at 10:11:12AM +0900, Namhyung Kim escreveu:
> The sched_switch event always captured from the scheduler function.  So
> it'd be great omit them from the callchain.  This patch marks the
> functions to be omitted by later patch.

I just reorderded this so that after applying 1 I could right away test
it, i.e. 2/3 was applied first.

- Arnaldo
 
> Cc: David Ahern <dsahern@...il.com>
> Signed-off-by: Namhyung Kim <namhyung@...nel.org>
> ---
>  tools/perf/builtin-sched.c | 21 +++++++++++++++++++++
>  tools/perf/util/symbol.h   |  1 +
>  2 files changed, 22 insertions(+)
> 
> diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
> index 829468defa07..cd14189d3943 100644
> --- a/tools/perf/builtin-sched.c
> +++ b/tools/perf/builtin-sched.c
> @@ -1965,7 +1965,28 @@ static bool is_idle_sample(struct perf_sched *sched,
>  
>  		return false;
>  	}
> +
>  	callchain_cursor_commit(cursor);
> +
> +	while (true) {
> +		struct callchain_cursor_node *node;
> +		struct symbol *sym;
> +
> +		node = callchain_cursor_current(cursor);
> +		if (node == NULL)
> +			break;
> +
> +		sym = node->sym;
> +		if (sym && sym->name) {
> +			if (!strcmp(sym->name, "schedule") ||
> +			    !strcmp(sym->name, "__schedule") ||
> +			    !strcmp(sym->name, "preempt_schedule"))
> +				sym->ignore = 1;
> +		}
> +
> +		callchain_cursor_advance(cursor);
> +	}
> +
>  	return false;
>  }
>  
> diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
> index dec7e2d44885..1bcbefc0c325 100644
> --- a/tools/perf/util/symbol.h
> +++ b/tools/perf/util/symbol.h
> @@ -58,6 +58,7 @@ struct symbol {
>  	u16		namelen;
>  	u8		binding;
>  	u8		idle:1;
> +	u8		ignore:1;
>  	u8		arch_sym;
>  	char		name[0];
>  };
> -- 
> 2.10.0