io_uring: add local task_work run helper that is entered locked

We have a few spots that drop the mutex just to run local task_work,
which immediately tries to grab it again. Add a helper that just passes
in whether we're locked already.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 31ac87e..a1692da 100644 (file)
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -1161,9 +1161,8 @@ static void __cold io_move_task_work_from_local(struct io_ring_ctx *ctx)
        }
 }
 
-int io_run_local_work(struct io_ring_ctx *ctx)
+int __io_run_local_work(struct io_ring_ctx *ctx, bool locked)
 {
-       bool locked;
        struct llist_node *node;
        struct llist_node fake;
        struct llist_node *current_final = NULL;
@@ -1178,8 +1177,6 @@ int io_run_local_work(struct io_ring_ctx *ctx)
                return -EEXIST;
        }
 
-       locked = mutex_trylock(&ctx->uring_lock);
-
        node = io_llist_xchg(&ctx->work_llist, &fake);
        ret = 0;
 again:
@@ -1204,12 +1201,24 @@ again:
                goto again;
        }
 
-       if (locked) {
+       if (locked)
                io_submit_flush_completions(ctx);
-               mutex_unlock(&ctx->uring_lock);
-       }
        trace_io_uring_local_work_run(ctx, ret, loops);
        return ret;
+
+}
+
+int io_run_local_work(struct io_ring_ctx *ctx)
+{
+       bool locked;
+       int ret;
+
+       locked = mutex_trylock(&ctx->uring_lock);
+       ret = __io_run_local_work(ctx, locked);
+       if (locked)
+               mutex_unlock(&ctx->uring_lock);
+
+       return ret;
 }
 
 static void io_req_tw_post(struct io_kiocb *req, bool *locked)

diff --git a/io_uring/io_uring.h b/io_uring/io_uring.h
index f417d75..0f90d1d 100644 (file)
--- a/io_uring/io_uring.h
+++ b/io_uring/io_uring.h
@@ -27,6 +27,7 @@ enum {
 struct io_uring_cqe *__io_get_cqe(struct io_ring_ctx *ctx);
 bool io_req_cqe_overflow(struct io_kiocb *req);
 int io_run_task_work_sig(struct io_ring_ctx *ctx);
+int __io_run_local_work(struct io_ring_ctx *ctx, bool locked);
 int io_run_local_work(struct io_ring_ctx *ctx);
 void io_req_complete_failed(struct io_kiocb *req, s32 res);
 void __io_req_complete(struct io_kiocb *req, unsigned issue_flags);