perf bench uprobe: Show diff to previous

Will be useful to show the incremental overhead as we do more stuff in
the BPF program attached to the uprobes.

Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andre Fredette <anfredet@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Dave Tucker <datucker@redhat.com>
Cc: Derek Barbosa <debarbos@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/20230719204910.539044-4-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/bench/uprobe.c b/tools/perf/bench/uprobe.c
index 60e7c43298d8cf56ce19cb77720b596613fc59db..a90e09f791c540a92e339de07351bb3bd31e3f32 100644 (file)
--- a/tools/perf/bench/uprobe.c
+++ b/tools/perf/bench/uprobe.c
@@ -36,24 +36,35 @@ static const char * const bench_uprobe_usage[] = {
 
 static int bench_uprobe_format__default_fprintf(const char *name, const char *unit, u64 diff, FILE *fp)
 {
-       static u64 baseline;
-       s64 diff_to_baseline = diff - baseline;
+       static u64 baseline, previous;
+       s64 diff_to_baseline = diff - baseline,
+           diff_to_previous = diff - previous;
        int printed = fprintf(fp, "# Executed %'d %s calls\n", loops, name);
 
        printed += fprintf(fp, " %14s: %'" PRIu64 " %ss", "Total time", diff, unit);
 
-       if (baseline)
+       if (baseline) {
                printed += fprintf(fp, " %s%'" PRId64 " to baseline", diff_to_baseline > 0 ? "+" : "", diff_to_baseline);
 
+               if (previous != baseline)
+                       fprintf(stdout, " %s%'" PRId64 " to previous", diff_to_previous > 0 ? "+" : "", diff_to_previous);
+       }
+
        printed += fprintf(fp, "\n\n %'.3f %ss/op", (double)diff / (double)loops, unit);
 
-       if (baseline)
+       if (baseline) {
                printed += fprintf(fp, " %'.3f %ss/op to baseline", (double)diff_to_baseline / (double)loops, unit);
-       else
+
+               if (previous != baseline)
+                       printed += fprintf(fp, " %'.3f %ss/op to previous", (double)diff_to_previous / (double)loops, unit);
+       } else {
                baseline = diff;
+       }
 
        fputc('\n', fp);
 
+       previous = diff;
+
        return printed + 1;
 }