diff options
author | Jan Kara <jack@suse.cz> | 2016-10-08 01:56:52 +0200 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-10-08 03:46:26 +0200 |
commit | c21dbe20f606219fe54faf555b7bc5565487c58f (patch) | |
tree | 91e57fe4aad1f1358f099521b570d9daf7b6a758 /fs/notify/notification.c | |
parent | fsnotify: drop notification_mutex before destroying event (diff) | |
download | linux-c21dbe20f606219fe54faf555b7bc5565487c58f.tar.xz linux-c21dbe20f606219fe54faf555b7bc5565487c58f.zip |
fsnotify: convert notification_mutex to a spinlock
notification_mutex is used to protect the list of pending events. As such
there's no reason to use a sleeping lock for it. Convert it to a
spinlock.
[jack@suse.cz: fixed version]
Link: http://lkml.kernel.org/r/1474031567-1831-1-git-send-email-jack@suse.cz
Link: http://lkml.kernel.org/r/1473797711-14111-5-git-send-email-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Eric Paris <eparis@redhat.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/notify/notification.c')
-rw-r--r-- | fs/notify/notification.c | 27 |
1 files changed, 15 insertions, 12 deletions
diff --git a/fs/notify/notification.c b/fs/notify/notification.c index 7d563dea52a4..8a7a8cd041e8 100644 --- a/fs/notify/notification.c +++ b/fs/notify/notification.c @@ -63,7 +63,8 @@ EXPORT_SYMBOL_GPL(fsnotify_get_cookie); /* return true if the notify queue is empty, false otherwise */ bool fsnotify_notify_queue_is_empty(struct fsnotify_group *group) { - BUG_ON(!mutex_is_locked(&group->notification_mutex)); + BUG_ON(IS_ENABLED(CONFIG_SMP) && + !spin_is_locked(&group->notification_lock)); return list_empty(&group->notification_list) ? true : false; } @@ -95,10 +96,10 @@ int fsnotify_add_event(struct fsnotify_group *group, pr_debug("%s: group=%p event=%p\n", __func__, group, event); - mutex_lock(&group->notification_mutex); + spin_lock(&group->notification_lock); if (group->shutdown) { - mutex_unlock(&group->notification_mutex); + spin_unlock(&group->notification_lock); return 2; } @@ -106,7 +107,7 @@ int fsnotify_add_event(struct fsnotify_group *group, ret = 2; /* Queue overflow event only if it isn't already queued */ if (!list_empty(&group->overflow_event->list)) { - mutex_unlock(&group->notification_mutex); + spin_unlock(&group->notification_lock); return ret; } event = group->overflow_event; @@ -116,7 +117,7 @@ int fsnotify_add_event(struct fsnotify_group *group, if (!list_empty(list) && merge) { ret = merge(list, event); if (ret) { - mutex_unlock(&group->notification_mutex); + spin_unlock(&group->notification_lock); return ret; } } @@ -124,7 +125,7 @@ int fsnotify_add_event(struct fsnotify_group *group, queue: group->q_len++; list_add_tail(&event->list, list); - mutex_unlock(&group->notification_mutex); + spin_unlock(&group->notification_lock); wake_up(&group->notification_waitq); kill_fasync(&group->fsn_fa, SIGIO, POLL_IN); @@ -139,7 +140,8 @@ struct fsnotify_event *fsnotify_remove_first_event(struct fsnotify_group *group) { struct fsnotify_event *event; - BUG_ON(!mutex_is_locked(&group->notification_mutex)); + BUG_ON(IS_ENABLED(CONFIG_SMP) && + !spin_is_locked(&group->notification_lock)); pr_debug("%s: group=%p\n", __func__, group); @@ -161,7 +163,8 @@ struct fsnotify_event *fsnotify_remove_first_event(struct fsnotify_group *group) */ struct fsnotify_event *fsnotify_peek_first_event(struct fsnotify_group *group) { - BUG_ON(!mutex_is_locked(&group->notification_mutex)); + BUG_ON(IS_ENABLED(CONFIG_SMP) && + !spin_is_locked(&group->notification_lock)); return list_first_entry(&group->notification_list, struct fsnotify_event, list); @@ -175,14 +178,14 @@ void fsnotify_flush_notify(struct fsnotify_group *group) { struct fsnotify_event *event; - mutex_lock(&group->notification_mutex); + spin_lock(&group->notification_lock); while (!fsnotify_notify_queue_is_empty(group)) { event = fsnotify_remove_first_event(group); - mutex_unlock(&group->notification_mutex); + spin_unlock(&group->notification_lock); fsnotify_destroy_event(group, event); - mutex_lock(&group->notification_mutex); + spin_lock(&group->notification_lock); } - mutex_unlock(&group->notification_mutex); + spin_unlock(&group->notification_lock); } /* |