perf tools: Reuse the path to the tracepoint /events/ directory

When using for_each_event() we needlessly rebuild the whole path to
the tracepoint directory, reuse the dir_path instead, saving some cycles
and reducing the size of the next patch.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-54bcs15n0cp6gwcgpc4hptyc@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Arnaldo Carvalho de Melo 2018-05-17 14:22:37 -03:00
parent 40c3c0c9ac
commit c02cab228e

View File

@ -156,13 +156,12 @@ struct event_symbol event_symbols_sw[PERF_COUNT_SW_MAX] = {
(strcmp(sys_dirent->d_name, ".")) && \
(strcmp(sys_dirent->d_name, "..")))
static int tp_event_has_id(struct dirent *sys_dir, struct dirent *evt_dir)
static int tp_event_has_id(const char *dir_path, struct dirent *evt_dir)
{
char evt_path[MAXPATHLEN];
int fd;
snprintf(evt_path, MAXPATHLEN, "%s/%s/%s/id", tracing_events_path,
sys_dir->d_name, evt_dir->d_name);
snprintf(evt_path, MAXPATHLEN, "%s/%s/id", dir_path, evt_dir->d_name);
fd = open(evt_path, O_RDONLY);
if (fd < 0)
return -EINVAL;
@ -171,12 +170,12 @@ static int tp_event_has_id(struct dirent *sys_dir, struct dirent *evt_dir)
return 0;
}
#define for_each_event(sys_dirent, evt_dir, evt_dirent) \
#define for_each_event(dir_path, evt_dir, evt_dirent) \
while ((evt_dirent = readdir(evt_dir)) != NULL) \
if (evt_dirent->d_type == DT_DIR && \
(strcmp(evt_dirent->d_name, ".")) && \
(strcmp(evt_dirent->d_name, "..")) && \
(!tp_event_has_id(sys_dirent, evt_dirent)))
(!tp_event_has_id(dir_path, evt_dirent)))
#define MAX_EVENT_LENGTH 512
@ -204,7 +203,7 @@ struct tracepoint_path *tracepoint_id_to_path(u64 config)
if (!evt_dir)
continue;
for_each_event(sys_dirent, evt_dir, evt_dirent) {
for_each_event(dir_path, evt_dir, evt_dirent) {
scnprintf(evt_path, MAXPATHLEN, "%s/%s/id", dir_path,
evt_dirent->d_name);
@ -2119,7 +2118,7 @@ restart:
if (!evt_dir)
continue;
for_each_event(sys_dirent, evt_dir, evt_dirent) {
for_each_event(dir_path, evt_dir, evt_dirent) {
if (event_glob != NULL &&
!strglobmatch(evt_dirent->d_name, event_glob))
continue;
@ -2199,7 +2198,7 @@ int is_valid_tracepoint(const char *event_string)
if (!evt_dir)
continue;
for_each_event(sys_dirent, evt_dir, evt_dirent) {
for_each_event(dir_path, evt_dir, evt_dirent) {
snprintf(evt_path, MAXPATHLEN, "%s:%s",
sys_dirent->d_name, evt_dirent->d_name);
if (!strcmp(evt_path, event_string)) {