linux-kernel - Re: [PATCH] perf annotate: Remove hist__account

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Date:   Thu, 14 Mar 2019 19:34:51 +0800
From:   "Jin, Yao" <yao.jin@...ux.intel.com>
To:     acme@...nel.org, jolsa@...nel.org, peterz@...radead.org,
        mingo@...hat.com, alexander.shishkin@...ux.intel.com
Cc:     Linux-kernel@...r.kernel.org, ak@...ux.intel.com,
        kan.liang@...el.com, yao.jin@...el.com
Subject: Re: [PATCH] perf annotate: Remove hist__account_cycles from callback

Any comments for this patch or any issue is found? In testing, I just 
feel it accelerates the perf annotate data processing.

Thanks
Jin Yao

On 3/13/2019 4:22 AM, Jin Yao wrote:
> The hist__account_cycles is executed when the hist_iter__branch_callback
> is called. But it looks it's not necessary. In hist__account_cycles, it
> already walks on all branch entries.
> 
> This patch moves the hist__account_cycles out of callback, now the data
> processing is much faster than before.
> 
> For example,
> perf record -b ...
> perf annotate
> 
> The before/after output should be no change.
> 
> Signed-off-by: Jin Yao <yao.jin@...ux.intel.com>
> ---
>   tools/perf/builtin-annotate.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/perf/builtin-annotate.c b/tools/perf/builtin-annotate.c
> index 67f9d9f..77deb3a 100644
> --- a/tools/perf/builtin-annotate.c
> +++ b/tools/perf/builtin-annotate.c
> @@ -159,8 +159,6 @@ static int hist_iter__branch_callback(struct hist_entry_iter *iter,
>   	struct perf_evsel *evsel = iter->evsel;
>   	int err;
>   
> -	hist__account_cycles(sample->branch_stack, al, sample, false);
> -
>   	bi = he->branch_info;
>   	err = addr_map_symbol__inc_samples(&bi->from, sample, evsel);
>   
> @@ -199,6 +197,8 @@ static int process_branch_callback(struct perf_evsel *evsel,
>   	if (a.map != NULL)
>   		a.map->dso->hit = 1;
>   
> +	hist__account_cycles(sample->branch_stack, al, sample, false);
> +
>   	ret = hist_entry_iter__add(&iter, &a, PERF_MAX_STACK_DEPTH, ann);
>   	return ret;
>   }
>