Commit b5d3ae20 authored by Jens Axboe's avatar Jens Axboe
Browse files

io_uring: handle TIF_NOTIFY_RESUME when checking for task_work 



If TIF_NOTIFY_RESUME is set, then we need to call resume_user_mode_work()
for PF_IO_WORKER threads. They never return to usermode, hence never get
a chance to process any items that are marked by this flag. Most notably
this includes the final put of files, but also any throttling markers set
by block cgroups.

Cc: stable@vger.kernel.org # 5.10+
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 8572df94

io_uring/io_uring.h

+8 −0
Original line number Diff line number Diff line
@@ -3,6 +3,7 @@ 


#include <linux/errno.h>

#include <linux/lockdep.h>

#include <linux/resume_user_mode.h>

#include <linux/io_uring_types.h>

#include <uapi/linux/eventpoll.h>

#include "io-wq.h"
@@ -274,6 +275,13 @@ static inline int io_run_task_work(void) 
	 */

	if (test_thread_flag(TIF_NOTIFY_SIGNAL))

		clear_notify_signal();

	/*

	 * PF_IO_WORKER never returns to userspace, so check here if we have

	 * notify work that needs processing.

	 */

	if (current->flags & PF_IO_WORKER &&

	    test_thread_flag(TIF_NOTIFY_RESUME))

		resume_user_mode_work(NULL);

	if (task_work_pending(current)) {

		__set_current_state(TASK_RUNNING);

		task_work_run();