diff options
| author | Tejun Heo <tj@kernel.org> | 2013-11-28 14:54:27 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-11-29 17:48:14 -0800 |
| commit | 024f647117d697165aaadf3f1af1343b7000149a (patch) | |
| tree | 79dcad5d6babfe359c443093fe7e5bed84322ef7 /fs | |
| parent | d19b9846df64d8845be682b6318bd1aee246cf60 (diff) | |
sysfs, kernfs: introduce kernfs_notify()
Introduce kernfs interface to wake up poll(2) which takes and returns
sysfs_dirents.
sysfs_notify_dirent() is renamed to kernfs_notify() and sysfs_notify()
is updated so that it doesn't directly grab sysfs_mutex but acquires
the target sysfs_dirents using sysfs_get_dirent().
sysfs_notify_dirent() is reimplemented as a dumb inline wrapper around
kernfs_notify().
This patch doesn't introduce any behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/sysfs/file.c | 33 |
1 files changed, 22 insertions, 11 deletions
diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c index 74e3478d9cb4..a68cbef3a674 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -851,7 +851,13 @@ static unsigned int kernfs_file_poll(struct file *filp, poll_table *wait) return DEFAULT_POLLMASK|POLLERR|POLLPRI; } -void sysfs_notify_dirent(struct sysfs_dirent *sd) +/** + * kernfs_notify - notify a kernfs file + * @sd: file to notify + * + * Notify @sd such that poll(2) on @sd wakes up. + */ +void kernfs_notify(struct sysfs_dirent *sd) { struct sysfs_open_dirent *od; unsigned long flags; @@ -868,22 +874,27 @@ void sysfs_notify_dirent(struct sysfs_dirent *sd) spin_unlock_irqrestore(&sysfs_open_dirent_lock, flags); } -EXPORT_SYMBOL_GPL(sysfs_notify_dirent); +EXPORT_SYMBOL_GPL(kernfs_notify); void sysfs_notify(struct kobject *k, const char *dir, const char *attr) { - struct sysfs_dirent *sd = k->sd; - - mutex_lock(&sysfs_mutex); + struct sysfs_dirent *sd = k->sd, *tmp; if (sd && dir) - sd = sysfs_find_dirent(sd, dir, NULL); - if (sd && attr) - sd = sysfs_find_dirent(sd, attr, NULL); - if (sd) - sysfs_notify_dirent(sd); + sd = sysfs_get_dirent(sd, dir); + else + sysfs_get(sd); - mutex_unlock(&sysfs_mutex); + if (sd && attr) { + tmp = sysfs_get_dirent(sd, attr); + sysfs_put(sd); + sd = tmp; + } + + if (sd) { + kernfs_notify(sd); + sysfs_put(sd); + } } EXPORT_SYMBOL_GPL(sysfs_notify); |