io_uring: only !null ptr to io_issue_sqe()

Pass only non-null @nxt to io_issue_sqe() and handle it at the caller's
side. And propagate it.

- kiocb_done() is only called from io_read() and io_write(), which are
only called from io_issue_sqe(), so it's @nxt != NULL

- io_put_req_find_next() is called either with explicitly non-null local
nxt, or from one of the functions in io_issue_sqe() switch (or their
callees).

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Pavel Begunkov 2019-11-21 23:21:03 +03:00 committed by Jens Axboe
parent b18fdf71e0
commit f9bd67f69a

View File

@ -990,21 +990,13 @@ static void io_free_req(struct io_kiocb *req)
* Drop reference to request, return next in chain (if there is one) if this
* was the last reference to this request.
*/
__attribute__((nonnull))
static void io_put_req_find_next(struct io_kiocb *req, struct io_kiocb **nxtptr)
{
struct io_kiocb *nxt = NULL;
io_req_find_next(req, &nxt);
io_req_find_next(req, nxtptr);
if (refcount_dec_and_test(&req->refs))
__io_free_req(req);
if (nxt) {
if (nxtptr)
*nxtptr = nxt;
else
io_queue_async_work(nxt);
}
}
static void io_put_req(struct io_kiocb *req)
@ -1488,7 +1480,7 @@ static inline void io_rw_done(struct kiocb *kiocb, ssize_t ret)
static void kiocb_done(struct kiocb *kiocb, ssize_t ret, struct io_kiocb **nxt,
bool in_async)
{
if (in_async && ret >= 0 && nxt && kiocb->ki_complete == io_complete_rw)
if (in_async && ret >= 0 && kiocb->ki_complete == io_complete_rw)
*nxt = __io_complete_rw(kiocb, ret);
else
io_rw_done(kiocb, ret);
@ -2585,6 +2577,7 @@ static int io_req_defer(struct io_kiocb *req)
return -EIOCBQUEUED;
}
__attribute__((nonnull))
static int io_issue_sqe(struct io_kiocb *req, struct io_kiocb **nxt,
bool force_nonblock)
{
@ -2901,10 +2894,13 @@ static struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req)
static void __io_queue_sqe(struct io_kiocb *req)
{
struct io_kiocb *nxt = io_prep_linked_timeout(req);
struct io_kiocb *linked_timeout = io_prep_linked_timeout(req);
struct io_kiocb *nxt = NULL;
int ret;
ret = io_issue_sqe(req, NULL, true);
ret = io_issue_sqe(req, &nxt, true);
if (nxt)
io_queue_async_work(nxt);
/*
* We async punt it if the file wasn't marked NOWAIT, or if the file
@ -2940,11 +2936,11 @@ err:
/* drop submission reference */
io_put_req(req);
if (nxt) {
if (linked_timeout) {
if (!ret)
io_queue_linked_timeout(nxt);
io_queue_linked_timeout(linked_timeout);
else
io_put_req(nxt);
io_put_req(linked_timeout);
}
/* and drop final reference, if we failed */