diff options
Diffstat (limited to 'fs/eventpoll.c')
| -rw-r--r-- | fs/eventpoll.c | 44 |
1 files changed, 18 insertions, 26 deletions
diff --git a/fs/eventpoll.c b/fs/eventpoll.c index 4284cd31eba..242fe1a66ce 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. */ @@ -274,22 +275,22 @@ 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; /* Slab cache used to allocate "struct epitem" */ -static kmem_cache_t *epi_cache; +static kmem_cache_t *epi_cache __read_mostly; /* Slab cache used to allocate "struct eppoll_entry" */ -static kmem_cache_t *pwq_cache; +static kmem_cache_t *pwq_cache __read_mostly; /* Virtual fs used to allocate inodes for eventpoll files */ -static struct vfsmount *eventpoll_mnt; +static struct vfsmount *eventpoll_mnt __read_mostly; /* File callbacks that implement the eventpoll file behaviour */ -static struct file_operations eventpoll_fops = { +static const struct file_operations eventpoll_fops = { .release = ep_eventpoll_close, .poll = ep_eventpoll_poll }; @@ -451,15 +452,6 @@ static void ep_poll_safewake(struct poll_safewake *psw, wait_queue_head_t *wq) } -/* Used to initialize the epoll bits inside the "struct file" */ -void eventpoll_init_file(struct file *file) -{ - - INIT_LIST_HEAD(&file->f_ep_links); - spin_lock_init(&file->f_ep_lock); -} - - /* * This is called from eventpoll_release() to unlink files from the eventpoll * interface. We need to have this facility to cleanup correctly files that are @@ -477,10 +469,10 @@ 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 +484,7 @@ void eventpoll_release_file(struct file *file) up_write(&ep->sem); } - up(&epsem); + mutex_unlock(&epmutex); } @@ -607,7 +599,7 @@ sys_epoll_ctl(int epfd, int op, int fd, struct epoll_event __user *event) switch (op) { case EPOLL_CTL_ADD: if (!epi) { - epds.events |= POLLERR | POLLHUP; + epds.events |= POLLERR | POLLHUP | POLLRDHUP; error = ep_insert(ep, &epds, tfile, fd); } else @@ -621,7 +613,7 @@ sys_epoll_ctl(int epfd, int op, int fd, struct epoll_event __user *event) break; case EPOLL_CTL_MOD: if (epi) { - epds.events |= POLLERR | POLLHUP; + epds.events |= POLLERR | POLLHUP | POLLRDHUP; error = ep_modify(ep, epi, &epds); } else error = -ENOENT; @@ -819,9 +811,9 @@ 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 +835,7 @@ static void ep_free(struct eventpoll *ep) ep_remove(ep, epi); } - up(&epsem); + mutex_unlock(&epmutex); } @@ -1615,7 +1607,7 @@ 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); |