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Diffstat (limited to 'tools/perf/util/debugfs.c')
-rw-r--r--tools/perf/util/debugfs.c160
1 files changed, 17 insertions, 143 deletions
diff --git a/tools/perf/util/debugfs.c b/tools/perf/util/debugfs.c
index a88fefc0cc0a..dd8b19319c03 100644
--- a/tools/perf/util/debugfs.c
+++ b/tools/perf/util/debugfs.c
@@ -2,8 +2,12 @@
#include "debugfs.h"
#include "cache.h"
+#include <linux/kernel.h>
+#include <sys/mount.h>
+
static int debugfs_premounted;
-static char debugfs_mountpoint[MAX_PATH+1];
+char debugfs_mountpoint[PATH_MAX + 1] = "/sys/kernel/debug";
+char tracing_events_path[PATH_MAX + 1] = "/sys/kernel/debug/tracing/events";
static const char *debugfs_known_mountpoints[] = {
"/sys/kernel/debug/",
@@ -11,32 +15,6 @@ static const char *debugfs_known_mountpoints[] = {
0,
};
-/* use this to force a umount */
-void debugfs_force_cleanup(void)
-{
- debugfs_find_mountpoint();
- debugfs_premounted = 0;
- debugfs_umount();
-}
-
-/* construct a full path to a debugfs element */
-int debugfs_make_path(const char *element, char *buffer, int size)
-{
- int len;
-
- if (strlen(debugfs_mountpoint) == 0) {
- buffer[0] = '\0';
- return -1;
- }
-
- len = strlen(debugfs_mountpoint) + strlen(element) + 1;
- if (len >= size)
- return len+1;
-
- snprintf(buffer, size-1, "%s/%s", debugfs_mountpoint, element);
- return 0;
-}
-
static int debugfs_found;
/* find the path to the mounted debugfs */
@@ -62,11 +40,9 @@ const char *debugfs_find_mountpoint(void)
/* give up and parse /proc/mounts */
fp = fopen("/proc/mounts", "r");
if (fp == NULL)
- die("Can't open /proc/mounts for read");
+ return NULL;
- while (fscanf(fp, "%*s %"
- STR(MAX_PATH)
- "s %99s %*s %*d %*d\n",
+ while (fscanf(fp, "%*s %" STR(PATH_MAX) "s %99s %*s %*d %*d\n",
debugfs_mountpoint, type) == 2) {
if (strcmp(type, "debugfs") == 0)
break;
@@ -95,15 +71,10 @@ int debugfs_valid_mountpoint(const char *debugfs)
return 0;
}
-
-int debugfs_valid_entry(const char *path)
+static void debugfs_set_tracing_events_path(const char *mountpoint)
{
- struct stat st;
-
- if (stat(path, &st))
- return -errno;
-
- return 0;
+ snprintf(tracing_events_path, sizeof(tracing_events_path), "%s/%s",
+ mountpoint, "tracing/events");
}
/* mount the debugfs somewhere if it's not mounted */
@@ -113,7 +84,7 @@ char *debugfs_mount(const char *mountpoint)
/* see if it's already mounted */
if (debugfs_find_mountpoint()) {
debugfs_premounted = 1;
- return debugfs_mountpoint;
+ goto out;
}
/* if not mounted and no argument */
@@ -129,112 +100,15 @@ char *debugfs_mount(const char *mountpoint)
return NULL;
/* save the mountpoint */
- strncpy(debugfs_mountpoint, mountpoint, sizeof(debugfs_mountpoint));
debugfs_found = 1;
-
+ strncpy(debugfs_mountpoint, mountpoint, sizeof(debugfs_mountpoint));
+out:
+ debugfs_set_tracing_events_path(debugfs_mountpoint);
return debugfs_mountpoint;
}
-/* umount the debugfs */
-
-int debugfs_umount(void)
-{
- char umountcmd[128];
- int ret;
-
- /* if it was already mounted, leave it */
- if (debugfs_premounted)
- return 0;
-
- /* make sure it's a valid mount point */
- ret = debugfs_valid_mountpoint(debugfs_mountpoint);
- if (ret)
- return ret;
-
- snprintf(umountcmd, sizeof(umountcmd),
- "/bin/umount %s", debugfs_mountpoint);
- return system(umountcmd);
-}
-
-int debugfs_write(const char *entry, const char *value)
+void debugfs_set_path(const char *mountpoint)
{
- char path[MAX_PATH+1];
- int ret, count;
- int fd;
-
- /* construct the path */
- snprintf(path, sizeof(path), "%s/%s", debugfs_mountpoint, entry);
-
- /* verify that it exists */
- ret = debugfs_valid_entry(path);
- if (ret)
- return ret;
-
- /* get how many chars we're going to write */
- count = strlen(value);
-
- /* open the debugfs entry */
- fd = open(path, O_RDWR);
- if (fd < 0)
- return -errno;
-
- while (count > 0) {
- /* write it */
- ret = write(fd, value, count);
- if (ret <= 0) {
- if (ret == EAGAIN)
- continue;
- close(fd);
- return -errno;
- }
- count -= ret;
- }
-
- /* close it */
- close(fd);
-
- /* return success */
- return 0;
-}
-
-/*
- * read a debugfs entry
- * returns the number of chars read or a negative errno
- */
-int debugfs_read(const char *entry, char *buffer, size_t size)
-{
- char path[MAX_PATH+1];
- int ret;
- int fd;
-
- /* construct the path */
- snprintf(path, sizeof(path), "%s/%s", debugfs_mountpoint, entry);
-
- /* verify that it exists */
- ret = debugfs_valid_entry(path);
- if (ret)
- return ret;
-
- /* open the debugfs entry */
- fd = open(path, O_RDONLY);
- if (fd < 0)
- return -errno;
-
- do {
- /* read it */
- ret = read(fd, buffer, size);
- if (ret == 0) {
- close(fd);
- return EOF;
- }
- } while (ret < 0 && errno == EAGAIN);
-
- /* close it */
- close(fd);
-
- /* make *sure* there's a null character at the end */
- buffer[ret] = '\0';
-
- /* return the number of chars read */
- return ret;
+ snprintf(debugfs_mountpoint, sizeof(debugfs_mountpoint), "%s", mountpoint);
+ debugfs_set_tracing_events_path(mountpoint);
}