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authorArnaldo Carvalho de Melo <acme@redhat.com>2009-12-16 10:49:27 -0500
committerIngo Molnar <mingo@elte.hu>2009-12-16 10:53:37 -0500
commitc351c2816177eb7d2979ec874b9b895abe9d6e5c (patch)
treeb6dd7fb4a5e048168319111e18082025c2e93f1b /tools
parent125c4fad1e60751ceaab1ee2a73bddf31213e5ca (diff)
perf diff: Use perf_session__fprintf_hists just like 'perf record'
That means that almost everything you can do with 'perf report' can be done with 'perf diff', for instance: $ perf record -f find / > /dev/null [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.062 MB perf.data (~2699 samples) ] $ perf record -f find / > /dev/null [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.062 MB perf.data (~2687 samples) ] perf diff | head -8 9.02% +1.00% find libc-2.10.1.so [.] _IO_vfprintf_internal 2.91% -1.00% find [kernel] [k] __kmalloc 2.85% -1.00% find [kernel] [k] ext4_htree_store_dirent 1.99% -1.00% find [kernel] [k] _atomic_dec_and_lock 2.44% find [kernel] [k] half_md4_transform $ So if you want to zoom into libc: $ perf diff --dsos libc-2.10.1.so | head -8 37.34% find [.] _IO_vfprintf_internal 10.34% find [.] __GI_memmove 8.25% +2.00% find [.] _int_malloc 5.07% -1.00% find [.] __GI_mempcpy 7.62% +2.00% find [.] _int_free $ And if there were multiple commands using libc, it is also possible to aggregate them all by using --sort symbol: $ perf diff --dsos libc-2.10.1.so --sort symbol | head -8 37.34% [.] _IO_vfprintf_internal 10.34% [.] __GI_memmove 8.25% +2.00% [.] _int_malloc 5.07% -1.00% [.] __GI_mempcpy 7.62% +2.00% [.] _int_free $ The displacement column now is off by default, to use it: perf diff -m --dsos libc-2.10.1.so --sort symbol | head -8 37.34% [.] _IO_vfprintf_internal 10.34% [.] __GI_memmove 8.25% +2.00% [.] _int_malloc 5.07% -1.00% +2 [.] __GI_mempcpy 7.62% +2.00% -1 [.] _int_free $ Using -t/--field-separator can be used for scripting: $ perf diff -t, -m --dsos libc-2.10.1.so --sort symbol | head -8 37.34, , ,[.] _IO_vfprintf_internal 10.34, , ,[.] __GI_memmove 8.25,+2.00%, ,[.] _int_malloc 5.07,-1.00%, +2,[.] __GI_mempcpy 7.62,+2.00%, -1,[.] _int_free 6.99,+1.00%, -1,[.] _IO_new_file_xsputn 1.89,-2.00%, +4,[.] __readdir64 $ Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1260978567-550-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'tools')
-rw-r--r--tools/perf/Documentation/perf-diff.txt29
-rw-r--r--tools/perf/Documentation/perf-report.txt4
-rw-r--r--tools/perf/builtin-diff.c90
-rw-r--r--tools/perf/builtin-report.c12
-rw-r--r--tools/perf/util/hist.c126
-rw-r--r--tools/perf/util/hist.h5
-rw-r--r--tools/perf/util/sort.c11
-rw-r--r--tools/perf/util/sort.h2
8 files changed, 169 insertions, 110 deletions
diff --git a/tools/perf/Documentation/perf-diff.txt b/tools/perf/Documentation/perf-diff.txt
index 6936fdb6d472..8974e208cba6 100644
--- a/tools/perf/Documentation/perf-diff.txt
+++ b/tools/perf/Documentation/perf-diff.txt
@@ -19,9 +19,32 @@ If no parameters are passed it will assume perf.data.old and perf.data.
19 19
20OPTIONS 20OPTIONS
21------- 21-------
22-p:: 22-d::
23--percentage:: 23--dsos=::
24 Show percentages instead of raw counts 24 Only consider symbols in these dsos. CSV that understands
25 file://filename entries.
26
27-C::
28--comms=::
29 Only consider symbols in these comms. CSV that understands
30 file://filename entries.
31
32-S::
33--symbols=::
34 Only consider these symbols. CSV that understands
35 file://filename entries.
36
37-s::
38--sort=::
39 Sort by key(s): pid, comm, dso, symbol.
40
41-t::
42--field-separator=::
43
44 Use a special separator character and don't pad with spaces, replacing
45 all occurances of this separator in symbol names (and other output)
46 with a '.' character, that thus it's the only non valid separator.
47
25-v:: 48-v::
26--verbose:: 49--verbose::
27 Be verbose, for instance, show the raw counts in addition to the 50 Be verbose, for instance, show the raw counts in addition to the
diff --git a/tools/perf/Documentation/perf-report.txt b/tools/perf/Documentation/perf-report.txt
index 9dccb180b7af..abfabe9147a4 100644
--- a/tools/perf/Documentation/perf-report.txt
+++ b/tools/perf/Documentation/perf-report.txt
@@ -39,6 +39,10 @@ OPTIONS
39 Only consider these symbols. CSV that understands 39 Only consider these symbols. CSV that understands
40 file://filename entries. 40 file://filename entries.
41 41
42-s::
43--sort=::
44 Sort by key(s): pid, comm, dso, symbol, parent.
45
42-w:: 46-w::
43--field-width=:: 47--field-width=::
44 Force each column width to the provided list, for large terminal 48 Force each column width to the provided list, for large terminal
diff --git a/tools/perf/builtin-diff.c b/tools/perf/builtin-diff.c
index ff91e9c291bb..66f100d249a8 100644
--- a/tools/perf/builtin-diff.c
+++ b/tools/perf/builtin-diff.c
@@ -16,10 +16,10 @@
16 16
17#include <stdlib.h> 17#include <stdlib.h>
18 18
19static char const *input_old = "perf.data.old", 19static char const *input_old = "perf.data.old",
20 *input_new = "perf.data"; 20 *input_new = "perf.data";
21static int force; 21static int force;
22static bool show_percent; 22static bool show_displacement;
23 23
24static int perf_session__add_hist_entry(struct perf_session *self, 24static int perf_session__add_hist_entry(struct perf_session *self,
25 struct addr_location *al, u64 count) 25 struct addr_location *al, u64 count)
@@ -162,70 +162,6 @@ static void perf_session__match_hists(struct perf_session *old_session,
162 } 162 }
163} 163}
164 164
165static size_t hist_entry__fprintf_matched(struct hist_entry *self,
166 unsigned long pos,
167 struct perf_session *session,
168 struct perf_session *pair_session,
169 FILE *fp)
170{
171 u64 old_count = 0;
172 char displacement[16];
173 size_t printed;
174
175 if (self->pair != NULL) {
176 long pdiff = (long)self->pair->position - (long)pos;
177 old_count = self->pair->count;
178 if (pdiff == 0)
179 goto blank;
180 snprintf(displacement, sizeof(displacement), "%+4ld", pdiff);
181 } else {
182blank: memset(displacement, ' ', sizeof(displacement));
183 }
184
185 printed = fprintf(fp, "%4lu %5.5s ", pos, displacement);
186
187 if (show_percent) {
188 double old_percent = 0, new_percent = 0, diff;
189
190 if (pair_session->events_stats.total > 0)
191 old_percent = (old_count * 100) / pair_session->events_stats.total;
192 if (session->events_stats.total > 0)
193 new_percent = (self->count * 100) / session->events_stats.total;
194
195 diff = old_percent - new_percent;
196 if (verbose)
197 printed += fprintf(fp, " %3.2f%% %3.2f%%", old_percent, new_percent);
198
199 if ((u64)diff != 0)
200 printed += fprintf(fp, " %+4.2F%%", diff);
201 else
202 printed += fprintf(fp, " ");
203 } else {
204 if (verbose)
205 printed += fprintf(fp, " %9Lu %9Lu", old_count, self->count);
206 printed += fprintf(fp, " %+9Ld", (s64)self->count - (s64)old_count);
207 }
208
209 return printed + fprintf(fp, " %25.25s %s\n",
210 self->map->dso->name, self->sym->name);
211}
212
213static size_t perf_session__fprintf_matched_hists(struct perf_session *self,
214 struct perf_session *pair,
215 FILE *fp)
216{
217 struct rb_node *nd;
218 size_t printed = 0;
219 unsigned long pos = 1;
220
221 for (nd = rb_first(&self->hists); nd; nd = rb_next(nd)) {
222 struct hist_entry *he = rb_entry(nd, struct hist_entry, rb_node);
223 printed += hist_entry__fprintf_matched(he, pos++, self, pair, fp);
224 }
225
226 return printed;
227}
228
229static int __cmd_diff(void) 165static int __cmd_diff(void)
230{ 166{
231 int ret, i; 167 int ret, i;
@@ -244,7 +180,8 @@ static int __cmd_diff(void)
244 } 180 }
245 181
246 perf_session__match_hists(session[0], session[1]); 182 perf_session__match_hists(session[0], session[1]);
247 perf_session__fprintf_matched_hists(session[1], session[0], stdout); 183 perf_session__fprintf_hists(session[1], session[0],
184 show_displacement, stdout);
248out_delete: 185out_delete:
249 for (i = 0; i < 2; ++i) 186 for (i = 0; i < 2; ++i)
250 perf_session__delete(session[i]); 187 perf_session__delete(session[i]);
@@ -258,13 +195,13 @@ static const char *const diff_usage[] = {
258static const struct option options[] = { 195static const struct option options[] = {
259 OPT_BOOLEAN('v', "verbose", &verbose, 196 OPT_BOOLEAN('v', "verbose", &verbose,
260 "be more verbose (show symbol address, etc)"), 197 "be more verbose (show symbol address, etc)"),
198 OPT_BOOLEAN('m', "displacement", &show_displacement,
199 "Show position displacement relative to baseline"),
261 OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace, 200 OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
262 "dump raw trace in ASCII"), 201 "dump raw trace in ASCII"),
263 OPT_BOOLEAN('f', "force", &force, "don't complain, do it"), 202 OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
264 OPT_BOOLEAN('m', "modules", &symbol_conf.use_modules, 203 OPT_BOOLEAN('m', "modules", &symbol_conf.use_modules,
265 "load module symbols - WARNING: use only with -k and LIVE kernel"), 204 "load module symbols - WARNING: use only with -k and LIVE kernel"),
266 OPT_BOOLEAN('p', "percentages", &show_percent,
267 "Don't shorten the pathnames taking into account the cwd"),
268 OPT_BOOLEAN('P', "full-paths", &event_ops.full_paths, 205 OPT_BOOLEAN('P', "full-paths", &event_ops.full_paths,
269 "Don't shorten the pathnames taking into account the cwd"), 206 "Don't shorten the pathnames taking into account the cwd"),
270 OPT_STRING('d', "dsos", &symbol_conf.dso_list_str, "dso[,dso...]", 207 OPT_STRING('d', "dsos", &symbol_conf.dso_list_str, "dso[,dso...]",
@@ -273,6 +210,11 @@ static const struct option options[] = {
273 "only consider symbols in these comms"), 210 "only consider symbols in these comms"),
274 OPT_STRING('S', "symbols", &symbol_conf.sym_list_str, "symbol[,symbol...]", 211 OPT_STRING('S', "symbols", &symbol_conf.sym_list_str, "symbol[,symbol...]",
275 "only consider these symbols"), 212 "only consider these symbols"),
213 OPT_STRING('s', "sort", &sort_order, "key[,key2...]",
214 "sort by key(s): pid, comm, dso, symbol, parent"),
215 OPT_STRING('t', "field-separator", &symbol_conf.field_sep, "separator",
216 "separator for columns, no spaces will be added between "
217 "columns '.' is reserved."),
276 OPT_END() 218 OPT_END()
277}; 219};
278 220
@@ -289,10 +231,16 @@ int cmd_diff(int argc, const char **argv, const char *prefix __used)
289 input_new = argv[0]; 231 input_new = argv[0];
290 } 232 }
291 233
234 symbol_conf.exclude_other = false;
292 if (symbol__init() < 0) 235 if (symbol__init() < 0)
293 return -1; 236 return -1;
294 237
295 setup_sorting(diff_usage, options); 238 setup_sorting(diff_usage, options);
296 setup_pager(); 239 setup_pager();
240
241 sort_entry__setup_elide(&sort_dso, symbol_conf.dso_list, "dso", NULL);
242 sort_entry__setup_elide(&sort_comm, symbol_conf.comm_list, "comm", NULL);
243 sort_entry__setup_elide(&sort_sym, symbol_conf.sym_list, "symbol", NULL);
244
297 return __cmd_diff(); 245 return __cmd_diff();
298} 246}
diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index cf1d370f51cb..e50a6b10ee6f 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -225,7 +225,7 @@ static int __cmd_report(void)
225 perf_session__collapse_resort(session); 225 perf_session__collapse_resort(session);
226 perf_session__output_resort(session, session->events_stats.total); 226 perf_session__output_resort(session, session->events_stats.total);
227 fprintf(stdout, "# Samples: %ld\n#\n", session->events_stats.total); 227 fprintf(stdout, "# Samples: %ld\n#\n", session->events_stats.total);
228 perf_session__fprintf_hists(session, stdout); 228 perf_session__fprintf_hists(session, NULL, false, stdout);
229 if (sort_order == default_sort_order && 229 if (sort_order == default_sort_order &&
230 parent_pattern == default_parent_pattern) 230 parent_pattern == default_parent_pattern)
231 fprintf(stdout, "#\n# (For a higher level overview, try: perf report --sort comm,dso)\n#\n"); 231 fprintf(stdout, "#\n# (For a higher level overview, try: perf report --sort comm,dso)\n#\n");
@@ -344,16 +344,6 @@ static const struct option options[] = {
344 OPT_END() 344 OPT_END()
345}; 345};
346 346
347static void sort_entry__setup_elide(struct sort_entry *self,
348 struct strlist *list,
349 const char *list_name, FILE *fp)
350{
351 if (list && strlist__nr_entries(list) == 1) {
352 fprintf(fp, "# %s: %s\n", list_name, strlist__entry(list, 0)->s);
353 self->elide = true;
354 }
355}
356
357int cmd_report(int argc, const char **argv, const char *prefix __used) 347int cmd_report(int argc, const char **argv, const char *prefix __used)
358{ 348{
359 argc = parse_options(argc, argv, options, report_usage, 0); 349 argc = parse_options(argc, argv, options, report_usage, 0);
diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
index 6e416a62e0d6..ecf853cdc0bf 100644
--- a/tools/perf/util/hist.c
+++ b/tools/perf/util/hist.c
@@ -454,34 +454,80 @@ static size_t hist_entry_callchain__fprintf(FILE *fp, struct hist_entry *self,
454 return ret; 454 return ret;
455} 455}
456 456
457static size_t hist_entry__fprintf(FILE *fp, struct hist_entry *self, 457static size_t hist_entry__fprintf(struct hist_entry *self,
458 struct perf_session *session) 458 struct perf_session *session,
459 struct perf_session *pair_session,
460 bool show_displacement,
461 long displacement, FILE *fp)
459{ 462{
460 struct sort_entry *se; 463 struct sort_entry *se;
464 u64 count, total;
465 const char *sep = symbol_conf.field_sep;
461 size_t ret; 466 size_t ret;
462 467
463 if (symbol_conf.exclude_other && !self->parent) 468 if (symbol_conf.exclude_other && !self->parent)
464 return 0; 469 return 0;
465 470
466 if (session->events_stats.total) 471 if (pair_session) {
467 ret = percent_color_fprintf(fp, 472 count = self->pair ? self->pair->count : 0;
468 symbol_conf.field_sep ? "%.2f" : " %6.2f%%", 473 total = pair_session->events_stats.total;
469 (self->count * 100.0) / session->events_stats.total); 474 } else {
475 count = self->count;
476 total = session->events_stats.total;
477 }
478
479 if (total)
480 ret = percent_color_fprintf(fp, sep ? "%.2f" : " %6.2f%%",
481 (count * 100.0) / total);
470 else 482 else
471 ret = fprintf(fp, symbol_conf.field_sep ? "%lld" : "%12lld ", self->count); 483 ret = fprintf(fp, sep ? "%lld" : "%12lld ", count);
472 484
473 if (symbol_conf.show_nr_samples) { 485 if (symbol_conf.show_nr_samples) {
474 if (symbol_conf.field_sep) 486 if (sep)
475 fprintf(fp, "%c%lld", *symbol_conf.field_sep, self->count); 487 fprintf(fp, "%c%lld", *sep, count);
476 else 488 else
477 fprintf(fp, "%11lld", self->count); 489 fprintf(fp, "%11lld", count);
490 }
491
492 if (pair_session) {
493 char bf[32];
494 double old_percent = 0, new_percent = 0, diff;
495
496 if (total > 0)
497 old_percent = (count * 100) / total;
498 if (session->events_stats.total > 0)
499 new_percent = (self->count * 100) / session->events_stats.total;
500
501 diff = old_percent - new_percent;
502
503 if ((u64)diff != 0)
504 snprintf(bf, sizeof(bf), "%+4.2F%%", diff);
505 else
506 snprintf(bf, sizeof(bf), " ");
507
508 if (sep)
509 ret += fprintf(fp, "%c%s", *sep, bf);
510 else
511 ret += fprintf(fp, "%11.11s", bf);
512
513 if (show_displacement) {
514 if (displacement)
515 snprintf(bf, sizeof(bf), "%+4ld", displacement);
516 else
517 snprintf(bf, sizeof(bf), " ");
518
519 if (sep)
520 fprintf(fp, "%c%s", *sep, bf);
521 else
522 fprintf(fp, "%6.6s", bf);
523 }
478 } 524 }
479 525
480 list_for_each_entry(se, &hist_entry__sort_list, list) { 526 list_for_each_entry(se, &hist_entry__sort_list, list) {
481 if (se->elide) 527 if (se->elide)
482 continue; 528 continue;
483 529
484 fprintf(fp, "%s", symbol_conf.field_sep ?: " "); 530 fprintf(fp, "%s", sep ?: " ");
485 ret += se->print(fp, self, se->width ? *se->width : 0); 531 ret += se->print(fp, self, se->width ? *se->width : 0);
486 } 532 }
487 533
@@ -504,29 +550,49 @@ static size_t hist_entry__fprintf(FILE *fp, struct hist_entry *self,
504 return ret; 550 return ret;
505} 551}
506 552
507size_t perf_session__fprintf_hists(struct perf_session *self, FILE *fp) 553size_t perf_session__fprintf_hists(struct perf_session *self,
554 struct perf_session *pair,
555 bool show_displacement, FILE *fp)
508{ 556{
509 struct hist_entry *pos;
510 struct sort_entry *se; 557 struct sort_entry *se;
511 struct rb_node *nd; 558 struct rb_node *nd;
512 size_t ret = 0; 559 size_t ret = 0;
560 unsigned long position = 1;
561 long displacement = 0;
513 unsigned int width; 562 unsigned int width;
563 const char *sep = symbol_conf.field_sep;
514 char *col_width = symbol_conf.col_width_list_str; 564 char *col_width = symbol_conf.col_width_list_str;
515 565
516 init_rem_hits(); 566 init_rem_hits();
517 567
518 fprintf(fp, "# Overhead"); 568 fprintf(fp, "# %s", pair ? "Baseline" : "Overhead");
569
519 if (symbol_conf.show_nr_samples) { 570 if (symbol_conf.show_nr_samples) {
520 if (symbol_conf.field_sep) 571 if (sep)
521 fprintf(fp, "%cSamples", *symbol_conf.field_sep); 572 fprintf(fp, "%cSamples", *sep);
522 else 573 else
523 fputs(" Samples ", fp); 574 fputs(" Samples ", fp);
524 } 575 }
576
577 if (pair) {
578 if (sep)
579 ret += fprintf(fp, "%cDelta", *sep);
580 else
581 ret += fprintf(fp, " Delta ");
582
583 if (show_displacement) {
584 if (sep)
585 ret += fprintf(fp, "%cDisplacement", *sep);
586 else
587 ret += fprintf(fp, " Displ");
588 }
589 }
590
525 list_for_each_entry(se, &hist_entry__sort_list, list) { 591 list_for_each_entry(se, &hist_entry__sort_list, list) {
526 if (se->elide) 592 if (se->elide)
527 continue; 593 continue;
528 if (symbol_conf.field_sep) { 594 if (sep) {
529 fprintf(fp, "%c%s", *symbol_conf.field_sep, se->header); 595 fprintf(fp, "%c%s", *sep, se->header);
530 continue; 596 continue;
531 } 597 }
532 width = strlen(se->header); 598 width = strlen(se->header);
@@ -545,12 +611,17 @@ size_t perf_session__fprintf_hists(struct perf_session *self, FILE *fp)
545 } 611 }
546 fprintf(fp, "\n"); 612 fprintf(fp, "\n");
547 613
548 if (symbol_conf.field_sep) 614 if (sep)
549 goto print_entries; 615 goto print_entries;
550 616
551 fprintf(fp, "# ........"); 617 fprintf(fp, "# ........");
552 if (symbol_conf.show_nr_samples) 618 if (symbol_conf.show_nr_samples)
553 fprintf(fp, " .........."); 619 fprintf(fp, " ..........");
620 if (pair) {
621 fprintf(fp, " ..........");
622 if (show_displacement)
623 fprintf(fp, " .....");
624 }
554 list_for_each_entry(se, &hist_entry__sort_list, list) { 625 list_for_each_entry(se, &hist_entry__sort_list, list) {
555 unsigned int i; 626 unsigned int i;
556 627
@@ -565,14 +636,23 @@ size_t perf_session__fprintf_hists(struct perf_session *self, FILE *fp)
565 for (i = 0; i < width; i++) 636 for (i = 0; i < width; i++)
566 fprintf(fp, "."); 637 fprintf(fp, ".");
567 } 638 }
568 fprintf(fp, "\n");
569 639
570 fprintf(fp, "#\n"); 640 fprintf(fp, "\n#\n");
571 641
572print_entries: 642print_entries:
573 for (nd = rb_first(&self->hists); nd; nd = rb_next(nd)) { 643 for (nd = rb_first(&self->hists); nd; nd = rb_next(nd)) {
574 pos = rb_entry(nd, struct hist_entry, rb_node); 644 struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);
575 ret += hist_entry__fprintf(fp, pos, self); 645
646 if (show_displacement) {
647 if (h->pair != NULL)
648 displacement = ((long)h->pair->position -
649 (long)position);
650 else
651 displacement = 0;
652 ++position;
653 }
654 ret += hist_entry__fprintf(h, self, pair, show_displacement,
655 displacement, fp);
576 } 656 }
577 657
578 free(rem_sq_bracket); 658 free(rem_sq_bracket);
diff --git a/tools/perf/util/hist.h b/tools/perf/util/hist.h
index c7ac78d93b0c..e5f99b24048b 100644
--- a/tools/perf/util/hist.h
+++ b/tools/perf/util/hist.h
@@ -21,6 +21,7 @@ void hist_entry__free(struct hist_entry *);
21 21
22void perf_session__output_resort(struct perf_session *self, u64 total_samples); 22void perf_session__output_resort(struct perf_session *self, u64 total_samples);
23void perf_session__collapse_resort(struct perf_session *self); 23void perf_session__collapse_resort(struct perf_session *self);
24size_t perf_session__fprintf_hists(struct perf_session *self, FILE *fp); 24size_t perf_session__fprintf_hists(struct perf_session *self,
25 25 struct perf_session *pair,
26 bool show_displacement, FILE *fp);
26#endif /* __PERF_HIST_H */ 27#endif /* __PERF_HIST_H */
diff --git a/tools/perf/util/sort.c b/tools/perf/util/sort.c
index cff1c316fa91..cb0f327de9e8 100644
--- a/tools/perf/util/sort.c
+++ b/tools/perf/util/sort.c
@@ -303,3 +303,14 @@ void setup_sorting(const char * const usagestr[], const struct option *opts)
303 303
304 free(str); 304 free(str);
305} 305}
306
307void sort_entry__setup_elide(struct sort_entry *self, struct strlist *list,
308 const char *list_name, FILE *fp)
309{
310 if (list && strlist__nr_entries(list) == 1) {
311 if (fp != NULL)
312 fprintf(fp, "# %s: %s\n", list_name,
313 strlist__entry(list, 0)->s);
314 self->elide = true;
315 }
316}
diff --git a/tools/perf/util/sort.h b/tools/perf/util/sort.h
index 925f083e1eee..753f9ea99fb0 100644
--- a/tools/perf/util/sort.h
+++ b/tools/perf/util/sort.h
@@ -101,5 +101,7 @@ extern int64_t sort__sym_cmp(struct hist_entry *, struct hist_entry *);
101extern int64_t sort__parent_cmp(struct hist_entry *, struct hist_entry *); 101extern int64_t sort__parent_cmp(struct hist_entry *, struct hist_entry *);
102extern size_t sort__parent_print(FILE *, struct hist_entry *, unsigned int); 102extern size_t sort__parent_print(FILE *, struct hist_entry *, unsigned int);
103extern int sort_dimension__add(const char *); 103extern int sort_dimension__add(const char *);
104void sort_entry__setup_elide(struct sort_entry *self, struct strlist *list,
105 const char *list_name, FILE *fp);
104 106
105#endif /* __PERF_SORT_H */ 107#endif /* __PERF_SORT_H */