Commit edf70ff5 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

block: refactor put_io_context 



Move the code to delay freeing the icqs into a separate helper.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarJan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20211209063131.18537-6-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 8a20c0c7

block/blk-ioc.c

+19 −19
Original line number Diff line number Diff line
@@ -143,6 +143,24 @@ static void ioc_release_fn(struct work_struct *work) 
	kmem_cache_free(iocontext_cachep, ioc);

}



/*

 * Releasing icqs requires reverse order double locking and we may already be

 * holding a queue_lock.  Do it asynchronously from a workqueue.

 */

static bool ioc_delay_free(struct io_context *ioc)

{

	unsigned long flags;



	spin_lock_irqsave(&ioc->lock, flags);

	if (!hlist_empty(&ioc->icq_list)) {

		queue_work(system_power_efficient_wq, &ioc->release_work);

		spin_unlock_irqrestore(&ioc->lock, flags);

		return true;

	}

	spin_unlock_irqrestore(&ioc->lock, flags);

	return false;

}



/**

 * put_io_context - put a reference of io_context

 * @ioc: io_context to put
@@ -152,26 +170,8 @@ static void ioc_release_fn(struct work_struct *work) 
 */

void put_io_context(struct io_context *ioc)

{

	unsigned long flags;

	bool free_ioc = false;



	BUG_ON(atomic_long_read(&ioc->refcount) <= 0);



	/*

	 * Releasing ioc requires reverse order double locking and we may

	 * already be holding a queue_lock.  Do it asynchronously from wq.

	 */

	if (atomic_long_dec_and_test(&ioc->refcount)) {

		spin_lock_irqsave(&ioc->lock, flags);

		if (!hlist_empty(&ioc->icq_list))

			queue_work(system_power_efficient_wq,

					&ioc->release_work);

		else

			free_ioc = true;

		spin_unlock_irqrestore(&ioc->lock, flags);

	}



	if (free_ioc)

	if (atomic_long_dec_and_test(&ioc->refcount) && !ioc_delay_free(ioc))

		kmem_cache_free(iocontext_cachep, ioc);

}

EXPORT_SYMBOL_GPL(put_io_context);