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Diffstat (limited to 'fs/eventpoll.c')
-rw-r--r--fs/eventpoll.c195
1 files changed, 110 insertions, 85 deletions
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 9900e333655a..6ab1dd0ca904 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -101,57 +101,6 @@
/* Maximum number of poll wake up nests we are allowing */
#define EP_MAX_POLLWAKE_NESTS 4
-/* Macro to allocate a "struct epitem" from the slab cache */
-#define EPI_MEM_ALLOC() (struct epitem *) kmem_cache_alloc(epi_cache, SLAB_KERNEL)
-
-/* Macro to free a "struct epitem" to the slab cache */
-#define EPI_MEM_FREE(p) kmem_cache_free(epi_cache, p)
-
-/* Macro to allocate a "struct eppoll_entry" from the slab cache */
-#define PWQ_MEM_ALLOC() (struct eppoll_entry *) kmem_cache_alloc(pwq_cache, SLAB_KERNEL)
-
-/* Macro to free a "struct eppoll_entry" to the slab cache */
-#define PWQ_MEM_FREE(p) kmem_cache_free(pwq_cache, p)
-
-/* Fast test to see if the file is an evenpoll file */
-#define IS_FILE_EPOLL(f) ((f)->f_op == &eventpoll_fops)
-
-/* Setup the structure that is used as key for the rb-tree */
-#define EP_SET_FFD(p, f, d) do { (p)->file = (f); (p)->fd = (d); } while (0)
-
-/* Compare rb-tree keys */
-#define EP_CMP_FFD(p1, p2) ((p1)->file > (p2)->file ? +1: \
- ((p1)->file < (p2)->file ? -1: (p1)->fd - (p2)->fd))
-
-/* Special initialization for the rb-tree node to detect linkage */
-#define EP_RB_INITNODE(n) (n)->rb_parent = (n)
-
-/* Removes a node from the rb-tree and marks it for a fast is-linked check */
-#define EP_RB_ERASE(n, r) do { rb_erase(n, r); (n)->rb_parent = (n); } while (0)
-
-/* Fast check to verify that the item is linked to the main rb-tree */
-#define EP_RB_LINKED(n) ((n)->rb_parent != (n))
-
-/*
- * Remove the item from the list and perform its initialization.
- * This is useful for us because we can test if the item is linked
- * using "EP_IS_LINKED(p)".
- */
-#define EP_LIST_DEL(p) do { list_del(p); INIT_LIST_HEAD(p); } while (0)
-
-/* Tells us if the item is currently linked */
-#define EP_IS_LINKED(p) (!list_empty(p))
-
-/* Get the "struct epitem" from a wait queue pointer */
-#define EP_ITEM_FROM_WAIT(p) ((struct epitem *) container_of(p, struct eppoll_entry, wait)->base)
-
-/* Get the "struct epitem" from an epoll queue wrapper */
-#define EP_ITEM_FROM_EPQUEUE(p) (container_of(p, struct ep_pqueue, pt)->epi)
-
-/* Tells if the epoll_ctl(2) operation needs an event copy from userspace */
-#define EP_OP_HASH_EVENT(op) ((op) != EPOLL_CTL_DEL)
-
-
struct epoll_filefd {
struct file *file;
int fd;
@@ -357,6 +306,82 @@ static struct dentry_operations eventpollfs_dentry_operations = {
+/* Fast test to see if the file is an evenpoll file */
+static inline int is_file_epoll(struct file *f)
+{
+ return f->f_op == &eventpoll_fops;
+}
+
+/* Setup the structure that is used as key for the rb-tree */
+static inline void ep_set_ffd(struct epoll_filefd *ffd,
+ struct file *file, int fd)
+{
+ ffd->file = file;
+ ffd->fd = fd;
+}
+
+/* Compare rb-tree keys */
+static inline int ep_cmp_ffd(struct epoll_filefd *p1,
+ struct epoll_filefd *p2)
+{
+ return (p1->file > p2->file ? +1:
+ (p1->file < p2->file ? -1 : p1->fd - p2->fd));
+}
+
+/* Special initialization for the rb-tree node to detect linkage */
+static inline void ep_rb_initnode(struct rb_node *n)
+{
+ n->rb_parent = n;
+}
+
+/* Removes a node from the rb-tree and marks it for a fast is-linked check */
+static inline void ep_rb_erase(struct rb_node *n, struct rb_root *r)
+{
+ rb_erase(n, r);
+ n->rb_parent = n;
+}
+
+/* Fast check to verify that the item is linked to the main rb-tree */
+static inline int ep_rb_linked(struct rb_node *n)
+{
+ return n->rb_parent != n;
+}
+
+/*
+ * Remove the item from the list and perform its initialization.
+ * This is useful for us because we can test if the item is linked
+ * using "ep_is_linked(p)".
+ */
+static inline void ep_list_del(struct list_head *p)
+{
+ list_del(p);
+ INIT_LIST_HEAD(p);
+}
+
+/* Tells us if the item is currently linked */
+static inline int ep_is_linked(struct list_head *p)
+{
+ return !list_empty(p);
+}
+
+/* Get the "struct epitem" from a wait queue pointer */
+static inline struct epitem * ep_item_from_wait(wait_queue_t *p)
+{
+ return container_of(p, struct eppoll_entry, wait)->base;
+}
+
+/* Get the "struct epitem" from an epoll queue wrapper */
+static inline struct epitem * ep_item_from_epqueue(poll_table *p)
+{
+ return container_of(p, struct ep_pqueue, pt)->epi;
+}
+
+/* Tells if the epoll_ctl(2) operation needs an event copy from userspace */
+static inline int ep_op_hash_event(int op)
+{
+ return op != EPOLL_CTL_DEL;
+}
+
/* Initialize the poll safe wake up structure */
static void ep_poll_safewake_init(struct poll_safewake *psw)
{
@@ -456,7 +481,7 @@ void eventpoll_release_file(struct file *file)
epi = list_entry(lsthead->next, struct epitem, fllink);
ep = epi->ep;
- EP_LIST_DEL(&epi->fllink);
+ ep_list_del(&epi->fllink);
down_write(&ep->sem);
ep_remove(ep, epi);
up_write(&ep->sem);
@@ -534,7 +559,7 @@ sys_epoll_ctl(int epfd, int op, int fd, struct epoll_event __user *event)
current, epfd, op, fd, event));
error = -EFAULT;
- if (EP_OP_HASH_EVENT(op) &&
+ if (ep_op_hash_event(op) &&
copy_from_user(&epds, event, sizeof(struct epoll_event)))
goto eexit_1;
@@ -560,7 +585,7 @@ sys_epoll_ctl(int epfd, int op, int fd, struct epoll_event __user *event)
* adding an epoll file descriptor inside itself.
*/
error = -EINVAL;
- if (file == tfile || !IS_FILE_EPOLL(file))
+ if (file == tfile || !is_file_epoll(file))
goto eexit_3;
/*
@@ -656,7 +681,7 @@ asmlinkage long sys_epoll_wait(int epfd, struct epoll_event __user *events,
* the user passed to us _is_ an eventpoll file.
*/
error = -EINVAL;
- if (!IS_FILE_EPOLL(file))
+ if (!is_file_epoll(file))
goto eexit_2;
/*
@@ -831,11 +856,11 @@ static struct epitem *ep_find(struct eventpoll *ep, struct file *file, int fd)
struct epitem *epi, *epir = NULL;
struct epoll_filefd ffd;
- EP_SET_FFD(&ffd, file, fd);
+ ep_set_ffd(&ffd, file, fd);
read_lock_irqsave(&ep->lock, flags);
for (rbp = ep->rbr.rb_node; rbp; ) {
epi = rb_entry(rbp, struct epitem, rbn);
- kcmp = EP_CMP_FFD(&ffd, &epi->ffd);
+ kcmp = ep_cmp_ffd(&ffd, &epi->ffd);
if (kcmp > 0)
rbp = rbp->rb_right;
else if (kcmp < 0)
@@ -875,7 +900,7 @@ static void ep_release_epitem(struct epitem *epi)
{
if (atomic_dec_and_test(&epi->usecnt))
- EPI_MEM_FREE(epi);
+ kmem_cache_free(epi_cache, epi);
}
@@ -886,10 +911,10 @@ static void ep_release_epitem(struct epitem *epi)
static void ep_ptable_queue_proc(struct file *file, wait_queue_head_t *whead,
poll_table *pt)
{
- struct epitem *epi = EP_ITEM_FROM_EPQUEUE(pt);
+ struct epitem *epi = ep_item_from_epqueue(pt);
struct eppoll_entry *pwq;
- if (epi->nwait >= 0 && (pwq = PWQ_MEM_ALLOC())) {
+ if (epi->nwait >= 0 && (pwq = kmem_cache_alloc(pwq_cache, SLAB_KERNEL))) {
init_waitqueue_func_entry(&pwq->wait, ep_poll_callback);
pwq->whead = whead;
pwq->base = epi;
@@ -912,7 +937,7 @@ static void ep_rbtree_insert(struct eventpoll *ep, struct epitem *epi)
while (*p) {
parent = *p;
epic = rb_entry(parent, struct epitem, rbn);
- kcmp = EP_CMP_FFD(&epi->ffd, &epic->ffd);
+ kcmp = ep_cmp_ffd(&epi->ffd, &epic->ffd);
if (kcmp > 0)
p = &parent->rb_right;
else
@@ -932,17 +957,17 @@ static int ep_insert(struct eventpoll *ep, struct epoll_event *event,
struct ep_pqueue epq;
error = -ENOMEM;
- if (!(epi = EPI_MEM_ALLOC()))
+ if (!(epi = kmem_cache_alloc(epi_cache, SLAB_KERNEL)))
goto eexit_1;
/* Item initialization follow here ... */
- EP_RB_INITNODE(&epi->rbn);
+ ep_rb_initnode(&epi->rbn);
INIT_LIST_HEAD(&epi->rdllink);
INIT_LIST_HEAD(&epi->fllink);
INIT_LIST_HEAD(&epi->txlink);
INIT_LIST_HEAD(&epi->pwqlist);
epi->ep = ep;
- EP_SET_FFD(&epi->ffd, tfile, fd);
+ ep_set_ffd(&epi->ffd, tfile, fd);
epi->event = *event;
atomic_set(&epi->usecnt, 1);
epi->nwait = 0;
@@ -978,7 +1003,7 @@ static int ep_insert(struct eventpoll *ep, struct epoll_event *event,
ep_rbtree_insert(ep, epi);
/* If the file is already "ready" we drop it inside the ready list */
- if ((revents & event->events) && !EP_IS_LINKED(&epi->rdllink)) {
+ if ((revents & event->events) && !ep_is_linked(&epi->rdllink)) {
list_add_tail(&epi->rdllink, &ep->rdllist);
/* Notify waiting tasks that events are available */
@@ -1007,11 +1032,11 @@ eexit_2:
* allocated wait queue.
*/
write_lock_irqsave(&ep->lock, flags);
- if (EP_IS_LINKED(&epi->rdllink))
- EP_LIST_DEL(&epi->rdllink);
+ if (ep_is_linked(&epi->rdllink))
+ ep_list_del(&epi->rdllink);
write_unlock_irqrestore(&ep->lock, flags);
- EPI_MEM_FREE(epi);
+ kmem_cache_free(epi_cache, epi);
eexit_1:
return error;
}
@@ -1050,14 +1075,14 @@ static int ep_modify(struct eventpoll *ep, struct epitem *epi, struct epoll_even
* If the item is not linked to the hash it means that it's on its
* way toward the removal. Do nothing in this case.
*/
- if (EP_RB_LINKED(&epi->rbn)) {
+ if (ep_rb_linked(&epi->rbn)) {
/*
* If the item is "hot" and it is not registered inside the ready
* list, push it inside. If the item is not "hot" and it is currently
* registered inside the ready list, unlink it.
*/
if (revents & event->events) {
- if (!EP_IS_LINKED(&epi->rdllink)) {
+ if (!ep_is_linked(&epi->rdllink)) {
list_add_tail(&epi->rdllink, &ep->rdllist);
/* Notify waiting tasks that events are available */
@@ -1097,9 +1122,9 @@ static void ep_unregister_pollwait(struct eventpoll *ep, struct epitem *epi)
while (!list_empty(lsthead)) {
pwq = list_entry(lsthead->next, struct eppoll_entry, llink);
- EP_LIST_DEL(&pwq->llink);
+ ep_list_del(&pwq->llink);
remove_wait_queue(pwq->whead, &pwq->wait);
- PWQ_MEM_FREE(pwq);
+ kmem_cache_free(pwq_cache, pwq);
}
}
}
@@ -1118,7 +1143,7 @@ static int ep_unlink(struct eventpoll *ep, struct epitem *epi)
* The check protect us from doing a double unlink ( crash ).
*/
error = -ENOENT;
- if (!EP_RB_LINKED(&epi->rbn))
+ if (!ep_rb_linked(&epi->rbn))
goto eexit_1;
/*
@@ -1133,14 +1158,14 @@ static int ep_unlink(struct eventpoll *ep, struct epitem *epi)
* This operation togheter with the above check closes the door to
* double unlinks.
*/
- EP_RB_ERASE(&epi->rbn, &ep->rbr);
+ ep_rb_erase(&epi->rbn, &ep->rbr);
/*
* If the item we are going to remove is inside the ready file descriptors
* we want to remove it from this list to avoid stale events.
*/
- if (EP_IS_LINKED(&epi->rdllink))
- EP_LIST_DEL(&epi->rdllink);
+ if (ep_is_linked(&epi->rdllink))
+ ep_list_del(&epi->rdllink);
error = 0;
eexit_1:
@@ -1174,8 +1199,8 @@ static int ep_remove(struct eventpoll *ep, struct epitem *epi)
/* Remove the current item from the list of epoll hooks */
spin_lock(&file->f_ep_lock);
- if (EP_IS_LINKED(&epi->fllink))
- EP_LIST_DEL(&epi->fllink);
+ if (ep_is_linked(&epi->fllink))
+ ep_list_del(&epi->fllink);
spin_unlock(&file->f_ep_lock);
/* We need to acquire the write IRQ lock before calling ep_unlink() */
@@ -1210,7 +1235,7 @@ static int ep_poll_callback(wait_queue_t *wait, unsigned mode, int sync, void *k
{
int pwake = 0;
unsigned long flags;
- struct epitem *epi = EP_ITEM_FROM_WAIT(wait);
+ struct epitem *epi = ep_item_from_wait(wait);
struct eventpoll *ep = epi->ep;
DNPRINTK(3, (KERN_INFO "[%p] eventpoll: poll_callback(%p) epi=%p ep=%p\n",
@@ -1228,7 +1253,7 @@ static int ep_poll_callback(wait_queue_t *wait, unsigned mode, int sync, void *k
goto is_disabled;
/* If this file is already in the ready list we exit soon */
- if (EP_IS_LINKED(&epi->rdllink))
+ if (ep_is_linked(&epi->rdllink))
goto is_linked;
list_add_tail(&epi->rdllink, &ep->rdllist);
@@ -1307,7 +1332,7 @@ static int ep_collect_ready_items(struct eventpoll *ep, struct list_head *txlist
lnk = lnk->next;
/* If this file is already in the ready list we exit soon */
- if (!EP_IS_LINKED(&epi->txlink)) {
+ if (!ep_is_linked(&epi->txlink)) {
/*
* This is initialized in this way so that the default
* behaviour of the reinjecting code will be to push back
@@ -1322,7 +1347,7 @@ static int ep_collect_ready_items(struct eventpoll *ep, struct list_head *txlist
/*
* Unlink the item from the ready list.
*/
- EP_LIST_DEL(&epi->rdllink);
+ ep_list_del(&epi->rdllink);
}
}
@@ -1401,7 +1426,7 @@ static void ep_reinject_items(struct eventpoll *ep, struct list_head *txlist)
epi = list_entry(txlist->next, struct epitem, txlink);
/* Unlink the current item from the transfer list */
- EP_LIST_DEL(&epi->txlink);
+ ep_list_del(&epi->txlink);
/*
* If the item is no more linked to the interest set, we don't
@@ -1410,8 +1435,8 @@ static void ep_reinject_items(struct eventpoll *ep, struct list_head *txlist)
* item is set to have an Edge Triggered behaviour, we don't have
* to push it back either.
*/
- if (EP_RB_LINKED(&epi->rbn) && !(epi->event.events & EPOLLET) &&
- (epi->revents & epi->event.events) && !EP_IS_LINKED(&epi->rdllink)) {
+ if (ep_rb_linked(&epi->rbn) && !(epi->event.events & EPOLLET) &&
+ (epi->revents & epi->event.events) && !ep_is_linked(&epi->rdllink)) {
list_add_tail(&epi->rdllink, &ep->rdllist);
ricnt++;
}