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Diffstat (limited to 'fs/eventpoll.c')
-rw-r--r--fs/eventpoll.c34
1 files changed, 11 insertions, 23 deletions
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index ba2f9ec7119..c5c424f23fd 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -234,8 +234,6 @@ struct ep_pqueue {
/*
* Configuration options available inside /proc/sys/fs/epoll/
*/
-/* Maximum number of epoll devices, per user */
-static int max_user_instances __read_mostly;
/* Maximum number of epoll watched descriptors, per user */
static int max_user_watches __read_mostly;
@@ -261,14 +259,6 @@ static int zero;
ctl_table epoll_table[] = {
{
- .procname = "max_user_instances",
- .data = &max_user_instances,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = &proc_dointvec_minmax,
- .extra1 = &zero,
- },
- {
.procname = "max_user_watches",
.data = &max_user_watches,
.maxlen = sizeof(int),
@@ -427,10 +417,10 @@ static int ep_remove(struct eventpoll *ep, struct epitem *epi)
ep_unregister_pollwait(ep, epi);
/* Remove the current item from the list of epoll hooks */
- spin_lock(&file->f_ep_lock);
+ spin_lock(&file->f_lock);
if (ep_is_linked(&epi->fllink))
list_del_init(&epi->fllink);
- spin_unlock(&file->f_ep_lock);
+ spin_unlock(&file->f_lock);
rb_erase(&epi->rbn, &ep->rbr);
@@ -491,7 +481,6 @@ static void ep_free(struct eventpoll *ep)
mutex_unlock(&epmutex);
mutex_destroy(&ep->mtx);
- atomic_dec(&ep->user->epoll_devs);
free_uid(ep->user);
kfree(ep);
}
@@ -549,7 +538,7 @@ void eventpoll_release_file(struct file *file)
struct epitem *epi;
/*
- * We don't want to get "file->f_ep_lock" because it is not
+ * We don't want to get "file->f_lock" because it is not
* necessary. It is not necessary because we're in the "struct file"
* cleanup path, and this means that noone is using this file anymore.
* So, for example, epoll_ctl() cannot hit here sicne if we reach this
@@ -558,6 +547,8 @@ void eventpoll_release_file(struct file *file)
* will correctly serialize the operation. We do need to acquire
* "ep->mtx" after "epmutex" because ep_remove() requires it when called
* from anywhere but ep_free().
+ *
+ * Besides, ep_remove() acquires the lock, so we can't hold it here.
*/
mutex_lock(&epmutex);
@@ -581,10 +572,6 @@ static int ep_alloc(struct eventpoll **pep)
struct eventpoll *ep;
user = get_current_user();
- error = -EMFILE;
- if (unlikely(atomic_read(&user->epoll_devs) >=
- max_user_instances))
- goto free_uid;
error = -ENOMEM;
ep = kzalloc(sizeof(*ep), GFP_KERNEL);
if (unlikely(!ep))
@@ -800,9 +787,9 @@ static int ep_insert(struct eventpoll *ep, struct epoll_event *event,
goto error_unregister;
/* Add the current item to the list of active epoll hook for this file */
- spin_lock(&tfile->f_ep_lock);
+ spin_lock(&tfile->f_lock);
list_add_tail(&epi->fllink, &tfile->f_ep_links);
- spin_unlock(&tfile->f_ep_lock);
+ spin_unlock(&tfile->f_lock);
/*
* Add the current item to the RB tree. All RB tree operations are
@@ -1141,7 +1128,6 @@ SYSCALL_DEFINE1(epoll_create1, int, flags)
flags & O_CLOEXEC);
if (fd < 0)
ep_free(ep);
- atomic_inc(&ep->user->epoll_devs);
error_return:
DNPRINTK(3, (KERN_INFO "[%p] eventpoll: sys_epoll_create(%d) = %d\n",
@@ -1366,8 +1352,10 @@ static int __init eventpoll_init(void)
struct sysinfo si;
si_meminfo(&si);
- max_user_instances = 128;
- max_user_watches = (((si.totalram - si.totalhigh) / 32) << PAGE_SHIFT) /
+ /*
+ * Allows top 4% of lomem to be allocated for epoll watches (per user).
+ */
+ max_user_watches = (((si.totalram - si.totalhigh) / 25) << PAGE_SHIFT) /
EP_ITEM_COST;
/* Initialize the structure used to perform safe poll wait head wake ups */