[PATCH 5/9] io_uring: refactor hrtimer_try_to_cancel uses

Pavel Begunkov
2021-04-13T02:03:09Z

Don't save return values of hrtimer_try_to_cancel() in a variable, but
use right away. It's in general safer to not have an intermediate
variable, which may be reused and passed out wrongly, but it be
contracted out. Also clean io_timeout_extract().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
fs/io_uring.c | 23 ++++++++---------------
1 file changed, 8 insertions(+), 15 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index eaa8f1af29cc..4f4b4f4bff2d 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -1272,10 +1272,8 @@ static void io_kill_timeout(struct io_kiocb *req, int status)
__must_hold(&req->ctx->completion_lock)
{
struct io_timeout_data *io = req->async_data;
- int ret;

- ret = hrtimer_try_to_cancel(&io->timer);
- if (ret != -1) {
+ if (hrtimer_try_to_cancel(&io->timer) != -1) {
atomic_set(&req->ctx->cq_timeouts,
atomic_read(&req->ctx->cq_timeouts) + 1);
list_del_init(&req->timeout.list);
@@ -1792,12 +1790,10 @@ static bool io_kill_linked_timeout(struct io_kiocb *req)
*/
if (link && (link->flags & REQ_F_LTIMEOUT_ACTIVE)) {
struct io_timeout_data *io = link->async_data;
- int ret;

io_remove_next_linked(req);
link->timeout.head = NULL;
- ret = hrtimer_try_to_cancel(&io->timer);
- if (ret != -1) {
+ if (hrtimer_try_to_cancel(&io->timer) != -1) {
io_cqring_fill_event(link, -ECANCELED, 0);
io_put_req_deferred(link, 1);
return true;
@@ -5533,21 +5529,18 @@ static struct io_kiocb *io_timeout_extract(struct io_ring_ctx *ctx,
{
struct io_timeout_data *io;
struct io_kiocb *req;
- int ret = -ENOENT;
+ bool found = false;

list_for_each_entry(req, &ctx->timeout_list, timeout.list) {
- if (user_data == req->user_data) {
- ret = 0;
+ found = user_data == req->user_data;
+ if (found)
break;
- }
}
-
- if (ret == -ENOENT)
- return ERR_PTR(ret);
+ if (!found)
+ return ERR_PTR(-ENOENT);

io = req->async_data;
- ret = hrtimer_try_to_cancel(&io->timer);
- if (ret == -1)
+ if (hrtimer_try_to_cancel(&io->timer) == -1)
return ERR_PTR(-EALREADY);
list_del_init(&req->timeout.list);
return req;
--
2.24.0