Commit ec3d07cb authored Dec 27, 2014 by Namhyung Kim Committed by Arnaldo Carvalho de Melo Jan 21, 2015

perf diff: Print diff result more precisely



Current perf diff result is somewhat confusing since it sometimes hide
small result and sometimes there's no result.  So do not hide small
result (less than 0.01%) and print "N/A" if baseline is not
recorded (for ratio and wdiff only).  Blank means the baseline is
available but its pairs are not.

Before:

  # Baseline    Delta  Shared Object      Symbol
  # ........  .......  .................  .........................
  #
       ...
       0.01%   -0.01%  [kernel.kallsyms]  [k] native_write_msr_safe
       0.01%           [kernel.kallsyms]  [k] scheduler_tick
       0.01%           [kernel.kallsyms]  [k] native_read_msr_safe
       0.00%           [kernel.kallsyms]  [k] __rcu_read_unlock
                       [kernel.kallsyms]  [k] _raw_spin_lock
               +0.01%  [kernel.kallsyms]  [k] apic_timer_interrupt
                       [kernel.kallsyms]  [k] read_tsc

After:

  # Baseline    Delta  Shared Object      Symbol
  # ........  .......  .................  .........................
  #
       ...
       0.01%   -0.01%  [kernel.kallsyms]  [k] native_write_msr_safe
       0.01%           [kernel.kallsyms]  [k] scheduler_tick
       0.01%           [kernel.kallsyms]  [k] native_read_msr_safe
       0.00%           [kernel.kallsyms]  [k] __rcu_read_unlock
               +0.01%  [kernel.kallsyms]  [k] _raw_spin_lock
               +0.01%  [kernel.kallsyms]  [k] apic_timer_interrupt
               +0.01%  [kernel.kallsyms]  [k] read_tsc

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1419656793-32756-3-git-send-email-namhyung@kernel.org


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

parent 38259a17

tools/perf/builtin-diff.c

+11 −7

Original line number	Diff line number	Diff line
		@@ -788,7 +788,7 @@ static int __hpp__color_compare(struct perf_hpp_fmt *fmt,
		char pfmt[20] = " ";

		if (!pair)
		goto dummy_print;
		goto no_print;

		switch (comparison_method) {
		case COMPUTE_DELTA:
		@@ -797,8 +797,6 @@ static int __hpp__color_compare(struct perf_hpp_fmt *fmt,
		else
		diff = compute_delta(he, pair);

		if (fabs(diff) < 0.01)
		goto dummy_print;
		scnprintf(pfmt, 20, "%%%+d.2f%%%%", dfmt->header_width - 1);
		return percent_color_snprintf(hpp->buf, hpp->size,
		pfmt, diff);
		@@ -829,6 +827,9 @@ static int __hpp__color_compare(struct perf_hpp_fmt *fmt,
		BUG_ON(1);
		}
		dummy_print:
		return scnprintf(hpp->buf, hpp->size, "%*s",
		dfmt->header_width, "N/A");
		no_print:
		return scnprintf(hpp->buf, hpp->size, "%*s",
		dfmt->header_width, pfmt);
		}
		@@ -879,14 +880,15 @@ hpp__entry_pair(struct hist_entry he, struct hist_entry pair,
		else
		diff = compute_delta(he, pair);

		if (fabs(diff) >= 0.01)
		scnprintf(buf, size, "%+4.2F%%", diff);
		break;

		case PERF_HPP_DIFF__RATIO:
		/* No point for ratio number if we are dummy.. */
		if (he->dummy)
		if (he->dummy) {
		scnprintf(buf, size, "N/A");
		break;
		}

		if (pair->diff.computed)
		ratio = pair->diff.period_ratio;
		@@ -899,8 +901,10 @@ hpp__entry_pair(struct hist_entry he, struct hist_entry pair,

		case PERF_HPP_DIFF__WEIGHTED_DIFF:
		/* No point for wdiff number if we are dummy.. */
		if (he->dummy)
		if (he->dummy) {
		scnprintf(buf, size, "N/A");
		break;
		}

		if (pair->diff.computed)
		wdiff = pair->diff.wdiff;

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