diff options
author | Arnaldo Carvalho de Melo <acme@redhat.com> | 2011-11-28 14:57:40 -0500 |
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committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2011-11-28 14:57:40 -0500 |
commit | ee29be625bd7b115d45eba4b0526ff3e24bf3ca0 (patch) | |
tree | 1ef1189e0fe02511642e5f74f463d888dfa34bec /tools/perf/util/evlist.c | |
parent | e7984b7bee2fca8f582f5bc2bf1e6c93420a5dd5 (diff) |
perf tools: Save some loops using perf_evlist__id2evsel
Since we already ask for PERF_SAMPLE_ID and use it to quickly find the
associated evsel, add handler func + data to struct perf_evsel to avoid
using chains of if(strcmp(event_name)) and also to avoid all the linear
list searches via trace_event_find.
To demonstrate the technique convert 'perf sched' to it:
# perf sched record sleep 5m
And then:
Performance counter stats for '/tmp/oldperf sched lat':
646.929438 task-clock # 0.999 CPUs utilized
9 context-switches # 0.000 M/sec
0 CPU-migrations # 0.000 M/sec
20,901 page-faults # 0.032 M/sec
1,290,144,450 cycles # 1.994 GHz
<not supported> stalled-cycles-frontend
<not supported> stalled-cycles-backend
1,606,158,439 instructions # 1.24 insns per cycle
339,088,395 branches # 524.151 M/sec
4,550,735 branch-misses # 1.34% of all branches
0.647524759 seconds time elapsed
Versus:
Performance counter stats for 'perf sched lat':
473.564691 task-clock # 0.999 CPUs utilized
9 context-switches # 0.000 M/sec
0 CPU-migrations # 0.000 M/sec
20,903 page-faults # 0.044 M/sec
944,367,984 cycles # 1.994 GHz
<not supported> stalled-cycles-frontend
<not supported> stalled-cycles-backend
1,442,385,571 instructions # 1.53 insns per cycle
308,383,106 branches # 651.195 M/sec
4,481,784 branch-misses # 1.45% of all branches
0.474215751 seconds time elapsed
[root@emilia ~]#
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-1kbzpl74lwi6lavpqke2u2p3@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/evlist.c')
-rw-r--r-- | tools/perf/util/evlist.c | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index d44e3df13a8f..b36f26fe767a 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c | |||
@@ -207,6 +207,48 @@ out_free_attrs: | |||
207 | return err; | 207 | return err; |
208 | } | 208 | } |
209 | 209 | ||
210 | static struct perf_evsel * | ||
211 | perf_evlist__find_tracepoint_by_id(struct perf_evlist *evlist, int id) | ||
212 | { | ||
213 | struct perf_evsel *evsel; | ||
214 | |||
215 | list_for_each_entry(evsel, &evlist->entries, node) { | ||
216 | if (evsel->attr.type == PERF_TYPE_TRACEPOINT && | ||
217 | (int)evsel->attr.config == id) | ||
218 | return evsel; | ||
219 | } | ||
220 | |||
221 | return NULL; | ||
222 | } | ||
223 | |||
224 | int perf_evlist__set_tracepoints_handlers(struct perf_evlist *evlist, | ||
225 | const struct perf_evsel_str_handler *assocs, | ||
226 | size_t nr_assocs) | ||
227 | { | ||
228 | struct perf_evsel *evsel; | ||
229 | int err; | ||
230 | size_t i; | ||
231 | |||
232 | for (i = 0; i < nr_assocs; i++) { | ||
233 | err = trace_event__id(assocs[i].name); | ||
234 | if (err < 0) | ||
235 | goto out; | ||
236 | |||
237 | evsel = perf_evlist__find_tracepoint_by_id(evlist, err); | ||
238 | if (evsel == NULL) | ||
239 | continue; | ||
240 | |||
241 | err = -EEXIST; | ||
242 | if (evsel->handler.func != NULL) | ||
243 | goto out; | ||
244 | evsel->handler.func = assocs[i].handler; | ||
245 | } | ||
246 | |||
247 | err = 0; | ||
248 | out: | ||
249 | return err; | ||
250 | } | ||
251 | |||
210 | void perf_evlist__disable(struct perf_evlist *evlist) | 252 | void perf_evlist__disable(struct perf_evlist *evlist) |
211 | { | 253 | { |
212 | int cpu, thread; | 254 | int cpu, thread; |