diff options
| -rw-r--r-- | fs/eventpoll.c | 23 |
1 files changed, 12 insertions, 11 deletions
diff --git a/fs/eventpoll.c b/fs/eventpoll.c index 4284cd31eba..f5d69f46ba9 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -34,6 +34,7 @@ #include <linux/eventpoll.h> #include <linux/mount.h> #include <linux/bitops.h> +#include <linux/mutex.h> #include <asm/uaccess.h> #include <asm/system.h> #include <asm/io.h> @@ -46,7 +47,7 @@ * LOCKING: * There are three level of locking required by epoll : * - * 1) epsem (semaphore) + * 1) epmutex (mutex) * 2) ep->sem (rw_semaphore) * 3) ep->lock (rw_lock) * @@ -67,9 +68,9 @@ * if a file has been pushed inside an epoll set and it is then * close()d without a previous call toepoll_ctl(EPOLL_CTL_DEL). * It is possible to drop the "ep->sem" and to use the global - * semaphore "epsem" (together with "ep->lock") to have it working, + * semaphore "epmutex" (together with "ep->lock") to have it working, * but having "ep->sem" will make the interface more scalable. - * Events that require holding "epsem" are very rare, while for + * Events that require holding "epmutex" are very rare, while for * normal operations the epoll private "ep->sem" will guarantee * a greater scalability. */ @@ -274,7 +275,7 @@ static struct super_block *eventpollfs_get_sb(struct file_system_type *fs_type, /* * This semaphore is used to serialize ep_free() and eventpoll_release_file(). */ -static struct semaphore epsem; +static struct mutex epmutex; /* Safe wake up implementation */ static struct poll_safewake psw; @@ -477,10 +478,10 @@ void eventpoll_release_file(struct file *file) * cleanup path, and this means that noone is using this file anymore. * The only hit might come from ep_free() but by holding the semaphore * will correctly serialize the operation. We do need to acquire - * "ep->sem" after "epsem" because ep_remove() requires it when called + * "ep->sem" after "epmutex" because ep_remove() requires it when called * from anywhere but ep_free(). */ - down(&epsem); + mutex_lock(&epmutex); while (!list_empty(lsthead)) { epi = list_entry(lsthead->next, struct epitem, fllink); @@ -492,7 +493,7 @@ void eventpoll_release_file(struct file *file) up_write(&ep->sem); } - up(&epsem); + mutex_unlock(&epmutex); } @@ -819,9 +820,9 @@ static void ep_free(struct eventpoll *ep) * We do not need to hold "ep->sem" here because the epoll file * is on the way to be removed and no one has references to it * anymore. The only hit might come from eventpoll_release_file() but - * holding "epsem" is sufficent here. + * holding "epmutex" is sufficent here. */ - down(&epsem); + mutex_lock(&epmutex); /* * Walks through the whole tree by unregistering poll callbacks. @@ -843,7 +844,7 @@ static void ep_free(struct eventpoll *ep) ep_remove(ep, epi); } - up(&epsem); + mutex_unlock(&epmutex); } @@ -1615,7 +1616,7 @@ static int __init eventpoll_init(void) { int error; - init_MUTEX(&epsem); + mutex_init(&epmutex); /* Initialize the structure used to perform safe poll wait head wake ups */ ep_poll_safewake_init(&psw); |