io_uring: don't put nodes under spinlocks

io_req_put_rsrc() doesn't need any locking, so move it out of
a spinlock section in __io_req_complete_post() and adjust helpers.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/d5b87a5f31270dade6805f7acafc4cc34b84b241.1680576071.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index a0b6483..596af20 100644 (file)
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -970,6 +970,7 @@ bool io_aux_cqe(struct io_ring_ctx *ctx, bool defer, u64 user_data, s32 res, u32
 static void __io_req_complete_post(struct io_kiocb *req)
 {
        struct io_ring_ctx *ctx = req->ctx;
+       struct io_rsrc_node *rsrc_node = NULL;
 
        io_cq_lock(ctx);
        if (!(req->flags & REQ_F_CQE_SKIP))
@@ -990,7 +991,7 @@ static void __io_req_complete_post(struct io_kiocb *req)
                }
                io_put_kbuf_comp(req);
                io_dismantle_req(req);
-               io_req_put_rsrc(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
@@ -1001,6 +1002,8 @@ static void __io_req_complete_post(struct io_kiocb *req)
                ctx->locked_free_nr++;
        }
        io_cq_unlock_post(ctx);
+
+       io_put_rsrc_node(rsrc_node);
 }
 
 void io_req_complete_post(struct io_kiocb *req, unsigned issue_flags)
@@ -1117,7 +1120,7 @@ __cold void io_free_req(struct io_kiocb *req)
 {
        struct io_ring_ctx *ctx = req->ctx;
 
-       io_req_put_rsrc(req);
+       io_put_rsrc_node(req->rsrc_node);
        io_dismantle_req(req);
        io_put_task_remote(req->task, 1);
 

diff --git a/io_uring/rsrc.h b/io_uring/rsrc.h
index 950535e..8164777 100644 (file)
--- a/io_uring/rsrc.h
+++ b/io_uring/rsrc.h
@@ -115,10 +115,10 @@ static inline void io_rsrc_put_node(struct io_rsrc_node *node, int nr)
                io_rsrc_node_ref_zero(node);
 }
 
-static inline void io_req_put_rsrc(struct io_kiocb *req)
+static inline void io_put_rsrc_node(struct io_rsrc_node *node)
 {
-       if (req->rsrc_node)
-               io_rsrc_put_node(req->rsrc_node, 1);
+       if (node)
+               io_rsrc_put_node(node, 1);
 }
 
 static inline void io_req_put_rsrc_locked(struct io_kiocb *req,