linux-kernel - [PATCH RFC 01/11] perf script: Move filter

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Date:   Mon, 21 Jun 2021 18:05:04 +0300
From:   Adrian Hunter <adrian.hunter@...el.com>
To:     Arnaldo Carvalho de Melo <acme@...nel.org>
Cc:     Jiri Olsa <jolsa@...hat.com>, Andi Kleen <ak@...ux.intel.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Ingo Molnar <mingo@...hat.com>,
        Mark Rutland <mark.rutland@....com>,
        Namhyung Kim <namhyung@...nel.org>,
        Leo Yan <leo.yan@...aro.org>,
        Kan Liang <kan.liang@...ux.intel.com>,
        linux-perf-users@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [PATCH RFC 01/11] perf script: Move filter_cpu() earlier

Generally, it should be more efficient if filter_cpu() comes before
machine__resolve() because filter_cpu() is much less code than
machine__resolve().

Example:

 $ perf record --sample-cpu -- make -C tools/perf >/dev/null

Before:

 $ perf stat -- perf script -C 0 >/dev/null

  Performance counter stats for 'perf script -C 0':

            116.94 msec task-clock                #    0.992 CPUs utilized
                 2      context-switches          #   17.103 /sec
                 0      cpu-migrations            #    0.000 /sec
             8,187      page-faults               #   70.011 K/sec
       478,351,812      cycles                    #    4.091 GHz
       564,785,464      instructions              #    1.18  insn per cycle
       114,341,105      branches                  #  977.789 M/sec
         2,615,495      branch-misses             #    2.29% of all branches

       0.117840576 seconds time elapsed

       0.085040000 seconds user
       0.032396000 seconds sys

After:

 $ perf stat -- perf script -C 0 >/dev/null

  Performance counter stats for 'perf script -C 0':

            107.45 msec task-clock                #    0.992 CPUs utilized
                 3      context-switches          #   27.919 /sec
                 0      cpu-migrations            #    0.000 /sec
             7,964      page-faults               #   74.117 K/sec
       438,417,260      cycles                    #    4.080 GHz
       522,571,855      instructions              #    1.19  insn per cycle
       105,187,488      branches                  #  978.921 M/sec
         2,356,261      branch-misses             #    2.24% of all branches

       0.108282546 seconds time elapsed

       0.095935000 seconds user
       0.011991000 seconds sys

Signed-off-by: Adrian Hunter <adrian.hunter@...el.com>
---
 tools/perf/builtin-script.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index 57488d60b64a..08a2b5d51018 100644
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -2191,6 +2191,9 @@ static int process_sample_event(struct perf_tool *tool,
 		return 0;
 	}
 
+	if (filter_cpu(sample))
+		return 0;
+
 	if (machine__resolve(machine, &al, sample) < 0) {
 		pr_err("problem processing %d event, skipping it.\n",
 		       event->header.type);
@@ -2200,9 +2203,6 @@ static int process_sample_event(struct perf_tool *tool,
 	if (al.filtered)
 		goto out_put;
 
-	if (filter_cpu(sample))
-		goto out_put;
-
 	if (scripting_ops) {
 		struct addr_location *addr_al_ptr = NULL;
 		struct addr_location addr_al;
-- 
2.17.1