[RFC 02/11] io_uringg: add io_should_fail_tw() helper

[Pavel Begunkov <asml.silence@gmail.com>]

Add a simple helper telling a tw handler whether it should cancel
requests, i.e. when the owner task is exiting.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 fs/io_uring.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 8011a61e6bd4..272a180ab7ee 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -1304,6 +1304,11 @@ static inline void req_ref_get(struct io_kiocb *req)
 	atomic_inc(&req->refs);
 }
 
+static inline bool io_should_fail_tw(struct io_kiocb *req)
+{
+	return unlikely(req->task->flags & PF_EXITING);
+}
+
 static inline void io_submit_flush_completions(struct io_ring_ctx *ctx)
 {
 	if (!wq_list_empty(&ctx->submit_state.compl_reqs))
@@ -2641,8 +2646,8 @@ static void io_req_task_cancel(struct io_kiocb *req, bool *locked)
 static void io_req_task_submit(struct io_kiocb *req, bool *locked)
 {
 	io_tw_lock(req->ctx, locked);
-	/* req->task == current here, checking PF_EXITING is safe */
-	if (likely(!(req->task->flags & PF_EXITING)))
+
+	if (!io_should_fail_tw(req))
 		io_queue_sqe(req);
 	else
 		io_req_complete_failed(req, -EFAULT);
@@ -5867,8 +5872,7 @@ static int io_poll_check_events(struct io_kiocb *req, bool locked)
 	struct io_ring_ctx *ctx = req->ctx;
 	int v;
 
-	/* req->task == current here, checking PF_EXITING is safe */
-	if (unlikely(req->task->flags & PF_EXITING))
+	if (io_should_fail_tw(req))
 		return -ECANCELED;
 
 	do {
@@ -7418,7 +7422,7 @@ static void io_req_task_link_timeout(struct io_kiocb *req, bool *locked)
 	int ret = -ENOENT;
 
 	if (prev) {
-		if (!(req->task->flags & PF_EXITING))
+		if (!io_should_fail_tw(req))
 			ret = io_try_cancel_userdata(req, prev->cqe.user_data);
 		io_req_complete_post(req, ret ?: -ETIME, 0);
 		io_put_req(prev);
-- 
2.36.0