io-wq: Drop intermediate step between pending list and active work

next_work is only used to make the work visible for
cancellation. Instead, we can just directly write to cur_work before
dropping the acct_lock and avoid the extra hop.

Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
Link: https://lore.kernel.org/r/20240416021054.3940-3-krisman@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Author: krisman

io_uring/io-wq.c

@@ -51,7 +51,6 @@ struct io_worker {
 	struct io_wq *wq;
 
 	struct io_wq_work *cur_work;
-	struct io_wq_work *next_work;
 	raw_spinlock_t lock;
 
 	struct completion ref_done;
@@ -539,7 +538,6 @@ static void io_assign_current_work(struct io_worker *worker,
 
 	raw_spin_lock(&worker->lock);
 	worker->cur_work = work;
-	worker->next_work = NULL;
 	raw_spin_unlock(&worker->lock);
 }
 
@@ -573,7 +571,7 @@ static void io_worker_handle_work(struct io_wq_acct *acct,
 			 * current work item for this worker.
 			 */
 			raw_spin_lock(&worker->lock);
-			worker->next_work = work;
+			worker->cur_work = work;
 			raw_spin_unlock(&worker->lock);
 		}
 
@@ -1008,8 +1006,7 @@ static bool io_wq_worker_cancel(struct io_worker *worker, void *data)
 	 * may dereference the passed in work.
 	 */
 	raw_spin_lock(&worker->lock);
-	if (__io_wq_worker_cancel(worker, match, worker->cur_work) ||
-	    __io_wq_worker_cancel(worker, match, worker->next_work))
+	if (__io_wq_worker_cancel(worker, match, worker->cur_work))
 		match->nr_running++;
 	raw_spin_unlock(&worker->lock);