diff options
author | Wang Nan <wangnan0@huawei.com> | 2015-07-10 07:36:10 +0000 |
---|---|---|
committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2015-07-20 17:49:17 -0300 |
commit | 4ba1faa19fa5f415bd69b1d7c366028332468bca (patch) | |
tree | 95a83aa5383a812da74eb3cc6abf33ab97236da1 /tools/perf/util/parse-events.c | |
parent | 15bfd2cc107a9971ac8aeb4b7724ced581a2ed30 (diff) |
perf record: Allow filtering perf's pid via --exclude-perf
This patch allows 'perf record' to exclude events issued by perf itself
by '--exclude-perf' option.
Before this patch, when doing something like:
# perf record -a -e syscalls:sys_enter_write <cmd>
One could easily get result like this:
# /tmp/perf report --stdio
...
# Overhead Command Shared Object Symbol
# ........ ....... .................. ....................
#
99.99% perf libpthread-2.18.so [.] __write_nocancel
0.01% ls libc-2.18.so [.] write
0.01% sshd libc-2.18.so [.] write
...
Where most events are generated by perf itself.
A shell trick can be done to filter perf itself out:
# cat << EOF > ./tmp
> #!/bin/sh
> exec perf record -e ... --filter="common_pid != \$\$" -a sleep 10
> EOF
# chmod a+x ./tmp
# ./tmp
However, doing so is user unfriendly.
This patch extracts evsel iteration framework introduced by patch 'perf
record: Apply filter to all events in a glob matching' into
foreach_evsel_in_last_glob(), and makes exclude_perf() function append
new filter expression to each evsel selected by a '-e' selector.
To avoid losing filters if user pass '--filter' after '--exclude-perf',
this patch uses perf_evsel__append_filter() in both case, instead of
perf_evsel__set_filter() which removes old filter. As a side effect, now
it is possible to use multiple '--filter' option for one selector. They
are combinded with '&&'.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1436513770-8896-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/parse-events.c')
-rw-r--r-- | tools/perf/util/parse-events.c | 83 |
1 files changed, 70 insertions, 13 deletions
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c index bbb7fbc2857e..4f807fc1b14a 100644 --- a/tools/perf/util/parse-events.c +++ b/tools/perf/util/parse-events.c @@ -1167,27 +1167,24 @@ int parse_events_option(const struct option *opt, const char *str, return ret; } -int parse_filter(const struct option *opt, const char *str, - int unset __maybe_unused) +static int +foreach_evsel_in_last_glob(struct perf_evlist *evlist, + int (*func)(struct perf_evsel *evsel, + const void *arg), + const void *arg) { - struct perf_evlist *evlist = *(struct perf_evlist **)opt->value; struct perf_evsel *last = NULL; + int err; if (evlist->nr_entries > 0) last = perf_evlist__last(evlist); do { - if (last == NULL || last->attr.type != PERF_TYPE_TRACEPOINT) { - fprintf(stderr, - "--filter option should follow a -e tracepoint option\n"); - return -1; - } - - if (perf_evsel__set_filter(last, str) < 0) { - fprintf(stderr, - "not enough memory to hold filter string\n"); + err = (*func)(last, arg); + if (err) return -1; - } + if (!last) + return 0; if (last->node.prev == &evlist->entries) return 0; @@ -1197,6 +1194,66 @@ int parse_filter(const struct option *opt, const char *str, return 0; } +static int set_filter(struct perf_evsel *evsel, const void *arg) +{ + const char *str = arg; + + if (evsel == NULL || evsel->attr.type != PERF_TYPE_TRACEPOINT) { + fprintf(stderr, + "--filter option should follow a -e tracepoint option\n"); + return -1; + } + + if (perf_evsel__append_filter(evsel, "&&", str) < 0) { + fprintf(stderr, + "not enough memory to hold filter string\n"); + return -1; + } + + return 0; +} + +int parse_filter(const struct option *opt, const char *str, + int unset __maybe_unused) +{ + struct perf_evlist *evlist = *(struct perf_evlist **)opt->value; + + return foreach_evsel_in_last_glob(evlist, set_filter, + (const void *)str); +} + +static int add_exclude_perf_filter(struct perf_evsel *evsel, + const void *arg __maybe_unused) +{ + char new_filter[64]; + + if (evsel == NULL || evsel->attr.type != PERF_TYPE_TRACEPOINT) { + fprintf(stderr, + "--exclude-perf option should follow a -e tracepoint option\n"); + return -1; + } + + snprintf(new_filter, sizeof(new_filter), "common_pid != %d", getpid()); + + if (perf_evsel__append_filter(evsel, "&&", new_filter) < 0) { + fprintf(stderr, + "not enough memory to hold filter string\n"); + return -1; + } + + return 0; +} + +int exclude_perf(const struct option *opt, + const char *arg __maybe_unused, + int unset __maybe_unused) +{ + struct perf_evlist *evlist = *(struct perf_evlist **)opt->value; + + return foreach_evsel_in_last_glob(evlist, add_exclude_perf_filter, + NULL); +} + static const char * const event_type_descriptors[] = { "Hardware event", "Software event", |