diff options
Diffstat (limited to 'tools/perf/util/debugfs.c')
-rw-r--r-- | tools/perf/util/debugfs.c | 160 |
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); } |