Add an ep_call_nested_nolock() variant which functions the same as
the current ep_call_nested(), except it does not acquire any locks. This
call wil be used by subsequent patches which have provide their own
'external' locking.
Signed-off-by: Jason Baron <jbaron@xxxxxxxxxx>
---
fs/eventpoll.c | 33 ++++++++++++++++++++++-----------
1 file changed, 22 insertions(+), 11 deletions(-)
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 2864d67..d0a021a 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -373,11 +373,17 @@ static inline int ep_events_available(struct eventpoll *ep)
return !list_empty(&ep->rdllist) || ep->ovflist != EP_UNACTIVE_PTR;
}
+#define ep_call_nested(ncalls, max_nests, nproc, priv, cookie, ctx) \
+ _ep_call_nested(ncalls, max_nests, nproc, priv, cookie, ctx, 1)
+
+#define ep_call_nested_nolock(ncalls, max_nests, nproc, priv, cookie, ctx) \
+ _ep_call_nested(ncalls, max_nests, nproc, priv, cookie, ctx, 0)
+
/**
- * ep_call_nested - Perform a bound (possibly) nested call, by checking
- * that the recursion limit is not exceeded, and that
- * the same nested call (by the meaning of same cookie) is
- * no re-entered.
+ * _ep_call_nested - Perform a bound (possibly) nested call, by checking
+ * that the recursion limit is not exceeded, and that
+ * the same nested call (by the meaning of same cookie) is
+ * no re-entered.
*
* @ncalls: Pointer to the nested_calls structure to be used for this call.
* @max_nests: Maximum number of allowed nesting calls.
@@ -385,21 +391,23 @@ static inline int ep_events_available(struct eventpoll *ep)
* @priv: Opaque data to be passed to the @nproc callback.
* @cookie: Cookie to be used to identify this nested call.
* @ctx: This instance context.
+ * @lock: protected by the lock or not
*
* Returns: Returns the code returned by the @nproc callback, or -1 if
* the maximum recursion limit has been exceeded.
*/
-static int ep_call_nested(struct nested_calls *ncalls, int max_nests,
+static int _ep_call_nested(struct nested_calls *ncalls, int max_nests,
int (*nproc)(void *, void *, int), void *priv,
- void *cookie, void *ctx)
+ void *cookie, void *ctx, bool lock)
{
int error, call_nests = 0;
- unsigned long flags;
+ unsigned long flags = 0;
struct list_head *lsthead = &ncalls->tasks_call_list;
struct nested_call_node *tncur;
struct nested_call_node tnode;
- spin_lock_irqsave(&ncalls->lock, flags);
+ if (lock)
+ spin_lock_irqsave(&ncalls->lock, flags);
/*
* Try to see if the current task is already inside this wakeup call.
@@ -423,16 +431,19 @@ static int ep_call_nested(struct nested_calls *ncalls, int max_nests,
tnode.cookie = cookie;
list_add(&tnode.llink, lsthead);
- spin_unlock_irqrestore(&ncalls->lock, flags);
+ if (lock)
+ spin_unlock_irqrestore(&ncalls->lock, flags);
/* Call the nested function */
error = (*nproc)(priv, cookie, call_nests);
/* Remove the current task from the list */
- spin_lock_irqsave(&ncalls->lock, flags);
+ if (lock)
+ spin_lock_irqsave(&ncalls->lock, flags);
list_del(&tnode.llink);
out_unlock:
- spin_unlock_irqrestore(&ncalls->lock, flags);
+ if (lock)
+ spin_unlock_irqrestore(&ncalls->lock, flags);
return error;
}
--
1.8.2.rc2
--
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