Commit 5988be39 authored by David S. Miller's avatar David S. Miller Committed by Willy Tarreau

irda: Fix lockdep annotations in hashbin_delete().

commit 4c03b862 upstream.

A nested lock depth was added to the hasbin_delete() code but it
doesn't actually work some well and results in tons of lockdep splats.

Fix the code instead to properly drop the lock around the operation
and just keep peeking the head of the hashbin queue.
Reported-by: default avatarDmitry Vyukov <dvyukov@google.com>
Tested-by: default avatarDmitry Vyukov <dvyukov@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: default avatarWilly Tarreau <w@1wt.eu>
parent 296a1ab2
......@@ -385,9 +385,6 @@ EXPORT_SYMBOL(hashbin_new);
* for deallocating this structure if it's complex. If not the user can
* just supply kfree, which should take care of the job.
*/
#ifdef CONFIG_LOCKDEP
static int hashbin_lock_depth = 0;
#endif
int hashbin_delete( hashbin_t* hashbin, FREE_FUNC free_func)
{
irda_queue_t* queue;
......@@ -398,22 +395,27 @@ int hashbin_delete( hashbin_t* hashbin, FREE_FUNC free_func)
IRDA_ASSERT(hashbin->magic == HB_MAGIC, return -1;);
/* Synchronize */
if ( hashbin->hb_type & HB_LOCK ) {
spin_lock_irqsave_nested(&hashbin->hb_spinlock, flags,
hashbin_lock_depth++);
}
if (hashbin->hb_type & HB_LOCK)
spin_lock_irqsave(&hashbin->hb_spinlock, flags);
/*
* Free the entries in the hashbin, TODO: use hashbin_clear when
* it has been shown to work
*/
for (i = 0; i < HASHBIN_SIZE; i ++ ) {
while (1) {
queue = dequeue_first((irda_queue_t**) &hashbin->hb_queue[i]);
while (queue ) {
if (free_func)
(*free_func)(queue);
queue = dequeue_first(
(irda_queue_t**) &hashbin->hb_queue[i]);
if (!queue)
break;
if (free_func) {
if (hashbin->hb_type & HB_LOCK)
spin_unlock_irqrestore(&hashbin->hb_spinlock, flags);
free_func(queue);
if (hashbin->hb_type & HB_LOCK)
spin_lock_irqsave(&hashbin->hb_spinlock, flags);
}
}
}
......@@ -422,12 +424,8 @@ int hashbin_delete( hashbin_t* hashbin, FREE_FUNC free_func)
hashbin->magic = ~HB_MAGIC;
/* Release lock */
if ( hashbin->hb_type & HB_LOCK) {
if (hashbin->hb_type & HB_LOCK)
spin_unlock_irqrestore(&hashbin->hb_spinlock, flags);
#ifdef CONFIG_LOCKDEP
hashbin_lock_depth--;
#endif
}
/*
* Free the hashbin structure
......
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