[PATCH 1/3] perf diff: Add 'delta-abs' compute method

From: Namhyung Kim
Date: Mon Feb 06 2017 - 02:20:49 EST


The 'delta-abs' compute method is same as 'delta' but shows entries with
bigger absolute delta first instead of sorting numerically. This is
only useful together with -o option.

Below is default output (-c delta):

$ perf diff -o 1 -c delta | grep -v ^# | head
42.22% +4.97% [kernel.kallsyms] [k] cfb_imageblit
0.62% +1.23% [kernel.kallsyms] [k] mutex_lock
+1.15% [kernel.kallsyms] [k] copy_user_generic_string
2.40% +0.95% [kernel.kallsyms] [k] bit_putcs
0.31% +0.79% [kernel.kallsyms] [k] link_path_walk
+0.64% [kernel.kallsyms] [k] kmem_cache_alloc
0.00% +0.57% [kernel.kallsyms] [k] __rcu_read_unlock
+0.45% [kernel.kallsyms] [k] alloc_set_pte
0.16% +0.45% [kernel.kallsyms] [k] menu_select
+0.41% ld-2.24.so [.] do_lookup_x

Now with 'delta-abs' it shows entries have bigger delta value either
positive or negative.

$ perf diff -o 1 -c delta-abs | grep -v ^# | head
42.22% +4.97% [kernel.kallsyms] [k] cfb_imageblit
12.72% -3.01% [kernel.kallsyms] [k] intel_idle
9.72% -1.31% [unknown] [.] 0x0000000000411343
0.62% +1.23% [kernel.kallsyms] [k] mutex_lock
2.40% +0.95% [kernel.kallsyms] [k] bit_putcs
0.31% +0.79% [kernel.kallsyms] [k] link_path_walk
1.35% -0.71% [kernel.kallsyms] [k] smp_call_function_single
0.00% +0.57% [kernel.kallsyms] [k] __rcu_read_unlock
0.16% +0.45% [kernel.kallsyms] [k] menu_select
0.72% -0.44% [kernel.kallsyms] [k] lookup_fast

Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
tools/perf/Documentation/perf-diff.txt | 6 ++++-
tools/perf/builtin-diff.c | 46 ++++++++++++++++++++++++++++++++--
2 files changed, 49 insertions(+), 3 deletions(-)

diff --git a/tools/perf/Documentation/perf-diff.txt b/tools/perf/Documentation/perf-diff.txt
index 3e9490b9c533..af80284cd2f6 100644
--- a/tools/perf/Documentation/perf-diff.txt
+++ b/tools/perf/Documentation/perf-diff.txt
@@ -86,7 +86,7 @@ OPTIONS

-c::
--compute::
- Differential computation selection - delta,ratio,wdiff (default is delta).
+ Differential computation selection - delta,ratio,wdiff,delta-abs (default is delta).
See COMPARISON METHODS section for more info.

-p::
@@ -181,6 +181,10 @@ delta
relative to how entries are filtered. Use --percentage=absolute to
prevent such fluctuation.

+delta-abs
+~~~~~~~~~
+Same as 'delta` method, but sort the result with the absolute values.
+
ratio
~~~~~
If specified the 'Ratio' column is displayed with value 'r' computed as:
diff --git a/tools/perf/builtin-diff.c b/tools/perf/builtin-diff.c
index 933aeec46f4a..781c9e60bd21 100644
--- a/tools/perf/builtin-diff.c
+++ b/tools/perf/builtin-diff.c
@@ -30,6 +30,7 @@ enum {
PERF_HPP_DIFF__RATIO,
PERF_HPP_DIFF__WEIGHTED_DIFF,
PERF_HPP_DIFF__FORMULA,
+ PERF_HPP_DIFF__DELTA_ABS,

PERF_HPP_DIFF__MAX_INDEX
};
@@ -73,11 +74,13 @@ enum {
COMPUTE_DELTA,
COMPUTE_RATIO,
COMPUTE_WEIGHTED_DIFF,
+ COMPUTE_DELTA_ABS,
COMPUTE_MAX,
};

const char *compute_names[COMPUTE_MAX] = {
[COMPUTE_DELTA] = "delta",
+ [COMPUTE_DELTA_ABS] = "delta-abs",
[COMPUTE_RATIO] = "ratio",
[COMPUTE_WEIGHTED_DIFF] = "wdiff",
};
@@ -86,6 +89,7 @@ static int compute;

static int compute_2_hpp[COMPUTE_MAX] = {
[COMPUTE_DELTA] = PERF_HPP_DIFF__DELTA,
+ [COMPUTE_DELTA_ABS] = PERF_HPP_DIFF__DELTA_ABS,
[COMPUTE_RATIO] = PERF_HPP_DIFF__RATIO,
[COMPUTE_WEIGHTED_DIFF] = PERF_HPP_DIFF__WEIGHTED_DIFF,
};
@@ -111,6 +115,10 @@ static struct header_column {
.name = "Delta",
.width = 7,
},
+ [PERF_HPP_DIFF__DELTA_ABS] = {
+ .name = "Delta Abs",
+ .width = 7,
+ },
[PERF_HPP_DIFF__RATIO] = {
.name = "Ratio",
.width = 14,
@@ -298,6 +306,7 @@ static int formula_fprintf(struct hist_entry *he, struct hist_entry *pair,
{
switch (compute) {
case COMPUTE_DELTA:
+ case COMPUTE_DELTA_ABS:
return formula_delta(he, pair, buf, size);
case COMPUTE_RATIO:
return formula_ratio(he, pair, buf, size);
@@ -461,6 +470,7 @@ static void hists__precompute(struct hists *hists)

switch (compute) {
case COMPUTE_DELTA:
+ case COMPUTE_DELTA_ABS:
compute_delta(he, pair);
break;
case COMPUTE_RATIO:
@@ -498,6 +508,13 @@ __hist_entry__cmp_compute(struct hist_entry *left, struct hist_entry *right,

return cmp_doubles(l, r);
}
+ case COMPUTE_DELTA_ABS:
+ {
+ double l = fabs(left->diff.period_ratio_delta);
+ double r = fabs(right->diff.period_ratio_delta);
+
+ return cmp_doubles(l, r);
+ }
case COMPUTE_RATIO:
{
double l = left->diff.period_ratio;
@@ -564,7 +581,7 @@ hist_entry__cmp_compute_idx(struct hist_entry *left, struct hist_entry *right,
if (!p_left || !p_right)
return p_left ? -1 : 1;

- if (c != COMPUTE_DELTA) {
+ if (c != COMPUTE_DELTA && c != COMPUTE_DELTA_ABS) {
/*
* The delta can be computed without the baseline, but
* others are not. Put those entries which have no
@@ -607,6 +624,15 @@ hist_entry__cmp_delta(struct perf_hpp_fmt *fmt,
}

static int64_t
+hist_entry__cmp_delta_abs(struct perf_hpp_fmt *fmt,
+ struct hist_entry *left, struct hist_entry *right)
+{
+ struct data__file *d = fmt_to_data_file(fmt);
+
+ return hist_entry__cmp_compute(right, left, COMPUTE_DELTA_ABS, d->idx);
+}
+
+static int64_t
hist_entry__cmp_ratio(struct perf_hpp_fmt *fmt,
struct hist_entry *left, struct hist_entry *right)
{
@@ -633,6 +659,14 @@ hist_entry__cmp_delta_idx(struct perf_hpp_fmt *fmt __maybe_unused,
}

static int64_t
+hist_entry__cmp_delta_abs_idx(struct perf_hpp_fmt *fmt __maybe_unused,
+ struct hist_entry *left, struct hist_entry *right)
+{
+ return hist_entry__cmp_compute_idx(right, left, COMPUTE_DELTA_ABS,
+ sort_compute);
+}
+
+static int64_t
hist_entry__cmp_ratio_idx(struct perf_hpp_fmt *fmt __maybe_unused,
struct hist_entry *left, struct hist_entry *right)
{
@@ -775,7 +809,7 @@ static const struct option options[] = {
OPT_BOOLEAN('b', "baseline-only", &show_baseline_only,
"Show only items with match in baseline"),
OPT_CALLBACK('c', "compute", &compute,
- "delta,ratio,wdiff:w1,w2 (default delta)",
+ "delta,delta-abs,ratio,wdiff:w1,w2 (default delta)",
"Entries differential computation selection",
setup_compute),
OPT_BOOLEAN('p', "period", &show_period,
@@ -945,6 +979,7 @@ hpp__entry_pair(struct hist_entry *he, struct hist_entry *pair,

switch (idx) {
case PERF_HPP_DIFF__DELTA:
+ case PERF_HPP_DIFF__DELTA_ABS:
if (pair->diff.computed)
diff = pair->diff.period_ratio_delta;
else
@@ -1118,6 +1153,10 @@ static void data__hpp_register(struct data__file *d, int idx)
fmt->color = hpp__color_wdiff;
fmt->sort = hist_entry__cmp_wdiff;
break;
+ case PERF_HPP_DIFF__DELTA_ABS:
+ fmt->color = hpp__color_delta;
+ fmt->sort = hist_entry__cmp_delta_abs;
+ break;
default:
fmt->sort = hist_entry__cmp_nop;
break;
@@ -1195,6 +1234,9 @@ static int ui_init(void)
case COMPUTE_WEIGHTED_DIFF:
fmt->sort = hist_entry__cmp_wdiff_idx;
break;
+ case COMPUTE_DELTA_ABS:
+ fmt->sort = hist_entry__cmp_delta_abs_idx;
+ break;
default:
BUG_ON(1);
}
--
2.11.0