perf ftrace latency: allow to hide empty buckets
Especially while using several buckets, it isn't uncommon to have some
of them empty and reading the histogram may be a bit more complex:
# perf ftrace latency -a -T mutex_lock --bucket-range 5 --max-latency 200
# DURATION | COUNT | GRAPH |
0 - 5 us | 14816 | ###################################### |
5 - 10 us | 1228 | ### |
10 - 15 us | 438 | # |
15 - 20 us | 106 | |
20 - 25 us | 21 | |
25 - 30 us | 11 | |
30 - 35 us | 1 | |
35 - 40 us | 2 | |
40 - 45 us | 4 | |
45 - 50 us | 0 | |
50 - 55 us | 1 | |
55 - 60 us | 0 | |
60 - 65 us | 1 | |
65 - 70 us | 1 | |
70 - 75 us | 1 | |
75 - 80 us | 2 | |
80 - 85 us | 0 | |
85 - 90 us | 1 | |
90 - 95 us | 0 | |
95 - 100 us | 1 | |
100 - 105 us | 0 | |
105 - 110 us | 0 | |
110 - 115 us | 0 | |
115 - 120 us | 0 | |
120 - 125 us | 1 | |
125 - 130 us | 0 | |
130 - 135 us | 0 | |
135 - 140 us | 1 | |
140 - 145 us | 0 | |
145 - 150 us | 0 | |
150 - 155 us | 0 | |
155 - 160 us | 0 | |
160 - 165 us | 0 | |
165 - 170 us | 0 | |
170 - 175 us | 0 | |
175 - 180 us | 0 | |
180 - 185 us | 0 | |
185 - 190 us | 0 | |
190 - 195 us | 0 | |
195 - 200 us | 0 | |
200 - ... us | 2 | |
Allow the optional flag --hide-empty to remove buckets with no element
and produce a more compact graph. This feature could be misleading since
there is no clear indication for missing buckets, for this reason it's
disabled by default.
# perf ftrace latency -a -T mutex_lock --bucket-range 5 --max-latency --hide-empty 200
# DURATION | COUNT | GRAPH |
0 - 5 us | 14816 | ###################################### |
5 - 10 us | 1228 | ### |
10 - 15 us | 438 | # |
15 - 20 us | 106 | |
20 - 25 us | 21 | |
25 - 30 us | 11 | |
30 - 35 us | 1 | |
35 - 40 us | 2 | |
40 - 45 us | 4 | |
50 - 55 us | 1 | |
60 - 65 us | 1 | |
65 - 70 us | 1 | |
70 - 75 us | 1 | |
75 - 80 us | 2 | |
85 - 90 us | 1 | |
95 - 100 us | 1 | |
120 - 125 us | 1 | |
135 - 140 us | 1 | |
200 - ... us | 2 | |
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/r/20250207080446.77630-2-gmonaco@redhat.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
gentwo / linux / .git / commit