epoll-do-not-take-global-epmutex-for-simple-topologies-fix

- use `bool' for boolean variables
- remove unneeded/undesirable cast of void*
- add missed ep_scan_ready_list() kerneldoc

Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Davide Libenzi <davidel@xmailserver.org>
Cc: Eric Wong <normalperson@yhbt.net>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Nathan Zimmer <nzimmer@sgi.com>
Cc: Nelson Elhage <nelhage@nelhage.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 5c64a6503dbf6e4905394056660bb3854f5db448..f7fe7e3ce664037694cf1c1d6f341267d4de941c 100644 (file)
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -585,13 +585,14 @@ static inline void ep_pm_stay_awake_rcu(struct epitem *epi)
  * @sproc: Pointer to the scan callback.
  * @priv: Private opaque data passed to the @sproc callback.
  * @depth: The current depth of recursive f_op->poll calls.
+ * @ep_locked: caller already holds ep->mtx
  *
  * Returns: The same integer error code returned by the @sproc callback.
  */
 static int ep_scan_ready_list(struct eventpoll *ep,
                              int (*sproc)(struct eventpoll *,
                                           struct list_head *, void *),
-                             void *priv, int depth, int ep_locked)
+                             void *priv, int depth, bool ep_locked)
 {
        int error, pwake = 0;
        unsigned long flags;
@@ -829,12 +830,12 @@ static void ep_ptable_queue_proc(struct file *file, wait_queue_head_t *whead,
 
 struct readyevents_arg {
        struct eventpoll *ep;
-       int locked;
+       bool locked;
 };
 
 static int ep_poll_readyevents_proc(void *priv, void *cookie, int call_nests)
 {
-       struct readyevents_arg *arg = (struct readyevents_arg *)priv;
+       struct readyevents_arg *arg = priv;
 
        return ep_scan_ready_list(arg->ep, ep_read_events_proc, NULL,
                                  call_nests + 1, arg->locked);
@@ -850,7 +851,7 @@ static unsigned int ep_eventpoll_poll(struct file *file, poll_table *wait)
         * During ep_insert() we already hold the ep->mtx for the tfile.
         * Prevent re-aquisition.
         */
-       arg.locked = ((wait && (wait->_qproc == ep_ptable_queue_proc)) ? 1 : 0);
+       arg.locked = wait && (wait->_qproc == ep_ptable_queue_proc);
        arg.ep = ep;
 
        /* Insert inside our poll wait queue */
@@ -1553,7 +1554,7 @@ static int ep_send_events(struct eventpoll *ep,
        esed.maxevents = maxevents;
        esed.events = events;
 
-       return ep_scan_ready_list(ep, ep_send_events_proc, &esed, 0, 0);
+       return ep_scan_ready_list(ep, ep_send_events_proc, &esed, 0, false);
 }
 
 static inline struct timespec ep_set_mstimeout(long ms)