perf tools: Do a few more directory handling optimizations
A few more optimizations for perf when dealing with directories.
Some of them significantly cut down the work which has to be
done. d_type should always be set; otherwise fix the kernel
code. And there are functions available to parse fstab-like
files, so use them.
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: a.p.zijlstra@chello.nl
Cc: acme@redhat.com
Cc: eranian@google.com
Cc: fweisbec@gmail.com
Cc: lizf@cn.fujitsu.com
Cc: paulus@samba.org
Cc: xiaoguangrong@cn.fujitsu.com
LKML-Reference: <200912192140.nBJLeSfA028905@hs20-bc2-1.build.redhat.com>
[ v2: two small stylistic fixlets ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/tools/perf/util/trace-event-info.c b/tools/perf/util/trace-event-info.c
index cace355..dfef238 100644
--- a/tools/perf/util/trace-event-info.c
+++ b/tools/perf/util/trace-event-info.c
@@ -20,6 +20,7 @@
*/
#define _GNU_SOURCE
#include <dirent.h>
+#include <mntent.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
@@ -103,29 +104,29 @@
{
static char debugfs[MAX_PATH+1];
static int debugfs_found;
- char type[100];
FILE *fp;
+ struct mntent *m;
if (debugfs_found)
return debugfs;
- if ((fp = fopen("/proc/mounts","r")) == NULL)
+ fp = setmntent("/proc/mounts", "r");
+ if (!fp)
die("Can't open /proc/mounts for read");
- while (fscanf(fp, "%*s %"
- STR(MAX_PATH)
- "s %99s %*s %*d %*d\n",
- debugfs, type) == 2) {
- if (strcmp(type, "debugfs") == 0)
+ while ((m = getmntent(fp)) != NULL) {
+ if (strcmp(m->mnt_type, "debugfs") == 0) {
+ strcpy(debugfs, m->mnt_dir);
+ debugfs_found = 1;
break;
+ }
}
- fclose(fp);
- if (strcmp(type, "debugfs") != 0)
+ endmntent(fp);
+
+ if (!debugfs_found)
die("debugfs not mounted, please mount");
- debugfs_found = 1;
-
return debugfs;
}
@@ -317,7 +318,8 @@
die("can't read directory '%s'", sys);
while ((dent = readdir(dir))) {
- if (strcmp(dent->d_name, ".") == 0 ||
+ if (dent->d_type != DT_DIR ||
+ strcmp(dent->d_name, ".") == 0 ||
strcmp(dent->d_name, "..") == 0 ||
!name_in_tp_list(dent->d_name, tps))
continue;
@@ -334,7 +336,8 @@
rewinddir(dir);
while ((dent = readdir(dir))) {
- if (strcmp(dent->d_name, ".") == 0 ||
+ if (dent->d_type != DT_DIR ||
+ strcmp(dent->d_name, ".") == 0 ||
strcmp(dent->d_name, "..") == 0 ||
!name_in_tp_list(dent->d_name, tps))
continue;
@@ -394,26 +397,21 @@
die("can't read directory '%s'", path);
while ((dent = readdir(dir))) {
- if (strcmp(dent->d_name, ".") == 0 ||
+ if (dent->d_type != DT_DIR ||
+ strcmp(dent->d_name, ".") == 0 ||
strcmp(dent->d_name, "..") == 0 ||
strcmp(dent->d_name, "ftrace") == 0 ||
!system_in_tp_list(dent->d_name, tps))
continue;
- sys = malloc_or_die(strlen(path) + strlen(dent->d_name) + 2);
- sprintf(sys, "%s/%s", path, dent->d_name);
- ret = stat(sys, &st);
- free(sys);
- if (ret < 0)
- continue;
- if (S_ISDIR(st.st_mode))
- count++;
+ count++;
}
write_or_die(&count, 4);
rewinddir(dir);
while ((dent = readdir(dir))) {
- if (strcmp(dent->d_name, ".") == 0 ||
+ if (dent->d_type != DT_DIR ||
+ strcmp(dent->d_name, ".") == 0 ||
strcmp(dent->d_name, "..") == 0 ||
strcmp(dent->d_name, "ftrace") == 0 ||
!system_in_tp_list(dent->d_name, tps))
@@ -422,10 +420,8 @@
sprintf(sys, "%s/%s", path, dent->d_name);
ret = stat(sys, &st);
if (ret >= 0) {
- if (S_ISDIR(st.st_mode)) {
- write_or_die(dent->d_name, strlen(dent->d_name) + 1);
- copy_event_system(sys, tps);
- }
+ write_or_die(dent->d_name, strlen(dent->d_name) + 1);
+ copy_event_system(sys, tps);
}
free(sys);
}