From: Ming Lei <ming.lei@redhat.com> mainline inclusion from mainline-v6.9-rc4 commit f39130004d3a9155d113284c19b5a7c2eccb43fe category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/ICJPON Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- Since commit 8f6c829491fe ("io_uring: remove struct io_tw_state::locked"), io_req_complete_post() is only called from io-wq submit work, where the request reference is guaranteed to be grabbed and won't drop to zero in io_req_complete_post(). Kill the dead code, meantime add req_ref_put() to put the reference. Cc: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Pavel Begunkov <asml.silence@gmail.com> Signed-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/1d8297e2046553153e763a52574f0e0f4d512f86.171233145... Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Long Li <leo.lilong@huawei.com> --- io_uring/io_uring.c | 37 ++----------------------------------- io_uring/refs.h | 7 +++++++ 2 files changed, 9 insertions(+), 35 deletions(-) diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index eed7070323e9..3a76f1a47508 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -956,7 +956,6 @@ bool io_req_post_cqe(struct io_kiocb *req, s32 res, u32 cflags) static void io_req_complete_post(struct io_kiocb *req, unsigned issue_flags) { struct io_ring_ctx *ctx = req->ctx; - struct io_rsrc_node *rsrc_node = NULL; /* * Handle special CQ sync cases via task_work. DEFER_TASKRUN requires @@ -973,42 +972,10 @@ static void io_req_complete_post(struct io_kiocb *req, unsigned issue_flags) if (!io_fill_cqe_req(ctx, req)) io_req_cqe_overflow(req); } - - /* - * If we're the last reference to this request, add to our locked - * free_list cache. - */ - if (req_ref_put_and_test(req)) { - if (req->flags & IO_REQ_LINK_FLAGS) { - if (req->flags & IO_DISARM_MASK) - io_disarm_next(req); - if (req->link) { - io_req_task_queue(req->link); - req->link = NULL; - } - } - io_put_kbuf_comp(req); - if (unlikely(req->flags & IO_REQ_CLEAN_FLAGS)) - io_clean_op(req); - io_put_file(req); - - rsrc_node = req->rsrc_node; - /* - * Selected buffer deallocation in io_clean_op() assumes that - * we don't hold ->completion_lock. Clean them here to avoid - * deadlocks. - */ - io_put_task_remote(req->task); - wq_list_add_head(&req->comp_list, &ctx->locked_free_list); - ctx->locked_free_nr++; - } io_cq_unlock_post(ctx); - if (rsrc_node) { - io_ring_submit_lock(ctx, issue_flags); - io_put_rsrc_node(ctx, rsrc_node); - io_ring_submit_unlock(ctx, issue_flags); - } + /* called from io-wq submit work only, the ref won't drop to zero */ + req_ref_put(req); } void io_req_defer_failed(struct io_kiocb *req, s32 res) diff --git a/io_uring/refs.h b/io_uring/refs.h index 1336de3f2a30..63982ead9f7d 100644 --- a/io_uring/refs.h +++ b/io_uring/refs.h @@ -33,6 +33,13 @@ static inline void req_ref_get(struct io_kiocb *req) atomic_inc(&req->refs); } +static inline void req_ref_put(struct io_kiocb *req) +{ + WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT)); + WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req)); + atomic_dec(&req->refs); +} + static inline void __io_req_set_refcount(struct io_kiocb *req, int nr) { if (!(req->flags & REQ_F_REFCOUNT)) { -- 2.39.2