| Message ID | deb4db0984b07e026d08b7bd1886cfc120d67f17.1668710788.git.asml.silence@gmail.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | io_uring: kill tw-related outdated comments | expand |
Pavel Begunkov <asml.silence@gmail.com> writes: > task_work fallback is executed from a workqueue, so current and > req->task are not necessarily the same. It's still safe to poke into it > as the request holds a task_struct reference. Makes sense to me. Feel free to add Reviewed-by: Gabriel Krisman Bertazi <krisman@suse.de> > > Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> > --- > io_uring/io_uring.c | 2 +- > io_uring/poll.c | 1 - > 2 files changed, 1 insertion(+), 2 deletions(-) > > diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c > index 94329c1ce91d..5a8a43fb6750 100644 > --- a/io_uring/io_uring.c > +++ b/io_uring/io_uring.c > @@ -1249,7 +1249,7 @@ static void io_req_task_cancel(struct io_kiocb *req, bool *locked) > 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))) > io_queue_sqe(req); > else > diff --git a/io_uring/poll.c b/io_uring/poll.c > index 2830b7daf952..5d4a0a4a379a 100644 > --- a/io_uring/poll.c > +++ b/io_uring/poll.c > @@ -214,7 +214,6 @@ static int io_poll_check_events(struct io_kiocb *req, bool *locked) > struct io_ring_ctx *ctx = req->ctx; > int v, ret; > > - /* req->task == current here, checking PF_EXITING is safe */ > if (unlikely(req->task->flags & PF_EXITING)) > return -ECANCELED;
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index 94329c1ce91d..5a8a43fb6750 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -1249,7 +1249,7 @@ static void io_req_task_cancel(struct io_kiocb *req, bool *locked) 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))) io_queue_sqe(req); else diff --git a/io_uring/poll.c b/io_uring/poll.c index 2830b7daf952..5d4a0a4a379a 100644 --- a/io_uring/poll.c +++ b/io_uring/poll.c @@ -214,7 +214,6 @@ static int io_poll_check_events(struct io_kiocb *req, bool *locked) struct io_ring_ctx *ctx = req->ctx; int v, ret; - /* req->task == current here, checking PF_EXITING is safe */ if (unlikely(req->task->flags & PF_EXITING)) return -ECANCELED;
task_work fallback is executed from a workqueue, so current and req->task are not necessarily the same. It's still safe to poke into it as the request holds a task_struct reference. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> --- io_uring/io_uring.c | 2 +- io_uring/poll.c | 1 - 2 files changed, 1 insertion(+), 2 deletions(-)