io_uring: unconditionally grab req->task (e3bc8e9d) · Commits · 戴 / test

fs/io_uring.c

+9 −38

Original line number	Diff line number	Diff line
		@@ -553,7 +553,6 @@ enum {
		REQ_F_BUFFER_SELECTED_BIT,
		REQ_F_NO_FILE_TABLE_BIT,
		REQ_F_WORK_INITIALIZED_BIT,
		REQ_F_TASK_PINNED_BIT,

		/* not a real bit, just to check we're not overflowing the space */
		__REQ_F_LAST_BIT,
		@@ -599,8 +598,6 @@ enum {
		REQ_F_NO_FILE_TABLE = BIT(REQ_F_NO_FILE_TABLE_BIT),
		/* io_wq_work is initialized */
		REQ_F_WORK_INITIALIZED = BIT(REQ_F_WORK_INITIALIZED_BIT),
		/* req->task is refcounted */
		REQ_F_TASK_PINNED = BIT(REQ_F_TASK_PINNED_BIT),
		};

		struct async_poll {
		@@ -942,14 +939,6 @@ struct sock io_uring_get_socket(struct file file)
		}
		EXPORT_SYMBOL(io_uring_get_socket);

		static void io_get_req_task(struct io_kiocb *req)
		{
		if (req->flags & REQ_F_TASK_PINNED)
		return;
		get_task_struct(req->task);
		req->flags \|= REQ_F_TASK_PINNED;
		}

		static inline void io_clean_op(struct io_kiocb *req)
		{
		if (req->flags & (REQ_F_NEED_CLEANUP \| REQ_F_BUFFER_SELECTED \|
		@@ -957,13 +946,6 @@ static inline void io_clean_op(struct io_kiocb *req)
		__io_clean_op(req);
		}

		/* not idempotent -- it doesn't clear REQ_F_TASK_PINNED */
		static void __io_put_req_task(struct io_kiocb *req)
		{
		if (req->flags & REQ_F_TASK_PINNED)
		put_task_struct(req->task);
		}

		static void io_sq_thread_drop_mm(void)
		{
		struct mm_struct *mm = current->mm;
		@@ -1589,7 +1571,8 @@ static void __io_free_req_finish(struct io_kiocb *req)
		{
		struct io_ring_ctx *ctx = req->ctx;

		__io_put_req_task(req);
		put_task_struct(req->task);

		if (likely(!io_is_fallback_req(req)))
		kmem_cache_free(req_cachep, req);
		else
		@@ -1916,7 +1899,6 @@ static void io_req_free_batch(struct req_batch rb, struct io_kiocb req)
		if (req->flags & REQ_F_LINK_HEAD)
		io_queue_next(req);

		if (req->flags & REQ_F_TASK_PINNED) {
		if (req->task != rb->task) {
		if (rb->task)
		put_task_struct_many(rb->task, rb->task_refs);
		@@ -1924,8 +1906,6 @@ static void io_req_free_batch(struct req_batch rb, struct io_kiocb req)
		rb->task_refs = 0;
		}
		rb->task_refs++;
		req->flags &= ~REQ_F_TASK_PINNED;
		}

		WARN_ON_ONCE(io_dismantle_req(req));
		rb->reqs[rb->to_free++] = req;
		@@ -2550,9 +2530,6 @@ static int io_prep_rw(struct io_kiocb req, const struct io_uring_sqe sqe,
		if (kiocb->ki_flags & IOCB_NOWAIT)
		req->flags \|= REQ_F_NOWAIT;

		if (kiocb->ki_flags & IOCB_DIRECT)
		io_get_req_task(req);

		if (force_nonblock)
		kiocb->ki_flags \|= IOCB_NOWAIT;

		@@ -2564,7 +2541,6 @@ static int io_prep_rw(struct io_kiocb req, const struct io_uring_sqe sqe,
		kiocb->ki_flags \|= IOCB_HIPRI;
		kiocb->ki_complete = io_complete_rw_iopoll;
		req->iopoll_completed = 0;
		io_get_req_task(req);
		} else {
		if (kiocb->ki_flags & IOCB_HIPRI)
		return -EINVAL;
		@@ -3132,8 +3108,6 @@ static bool io_rw_should_retry(struct io_kiocb *req)
		kiocb->ki_flags \|= IOCB_WAITQ;
		kiocb->ki_flags &= ~IOCB_NOWAIT;
		kiocb->ki_waitq = wait;

		io_get_req_task(req);
		return true;
		}

		@@ -4965,7 +4939,6 @@ static bool io_arm_poll_handler(struct io_kiocb *req)
		apoll->double_poll = NULL;

		req->flags \|= REQ_F_POLLED;
		io_get_req_task(req);
		req->apoll = apoll;
		INIT_HLIST_NODE(&req->hash_node);

		@@ -5148,8 +5121,6 @@ static int io_poll_add_prep(struct io_kiocb req, const struct io_uring_sqe sqe
		#endif
		poll->events = demangle_poll(events) \| EPOLLERR \| EPOLLHUP \|
		(events & EPOLLEXCLUSIVE);

		io_get_req_task(req);
		return 0;
		}

		@@ -6336,7 +6307,6 @@ static int io_submit_sqe(struct io_kiocb req, const struct io_uring_sqe sqe,
		return ret;
		}
		trace_io_uring_link(ctx, req, head);
		io_get_req_task(req);
		list_add_tail(&req->link_list, &head->link_list);

		/* last request of a link, enqueue the link */
		@@ -6461,6 +6431,7 @@ static int io_init_req(struct io_ring_ctx ctx, struct io_kiocb req,
		/* one is dropped after submission, the other at completion */
		refcount_set(&req->refs, 2);
		req->task = current;
		get_task_struct(req->task);
		req->result = 0;

		if (unlikely(req->opcode >= IORING_OP_LAST))

Admin message