io_uring: don't iterate io_uring_cancel_files()

[ Upstream commit b52fda00dd9df8b4a6de5784df94f9617f6133a1 ]

io_uring_cancel_files() guarantees to cancel all matching requests,
that's not necessary to do that in a loop. Move it up in the callchain
into io_uring_cancel_task_requests().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 8e9a345..9faa1cb 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -8654,16 +8654,10 @@ static void io_cancel_defer_files(struct io_ring_ctx *ctx,
        }
 }
 
-/*
- * Returns true if we found and killed one or more files pinning requests
- */
-static bool io_uring_cancel_files(struct io_ring_ctx *ctx,
+static void io_uring_cancel_files(struct io_ring_ctx *ctx,
                                  struct task_struct *task,
                                  struct files_struct *files)
 {
-       if (list_empty_careful(&ctx->inflight_list))
-               return false;
-
        while (!list_empty_careful(&ctx->inflight_list)) {
                struct io_kiocb *cancel_req = NULL, *req;
                DEFINE_WAIT(wait);
@@ -8698,8 +8692,6 @@ static bool io_uring_cancel_files(struct io_ring_ctx *ctx,
                schedule();
                finish_wait(&ctx->inflight_wait, &wait);
        }
-
-       return true;
 }
 
 static bool io_cancel_task_cb(struct io_wq_work *work, void *data)
@@ -8710,15 +8702,12 @@ static bool io_cancel_task_cb(struct io_wq_work *work, void *data)
        return io_task_match(req, task);
 }
 
-static bool __io_uring_cancel_task_requests(struct io_ring_ctx *ctx,
-                                           struct task_struct *task,
-                                           struct files_struct *files)
+static void __io_uring_cancel_task_requests(struct io_ring_ctx *ctx,
+                                           struct task_struct *task)
 {
-       bool ret;
-
-       ret = io_uring_cancel_files(ctx, task, files);
-       if (!files) {
+       while (1) {
                enum io_wq_cancel cret;
+               bool ret = false;
 
                cret = io_wq_cancel_cb(ctx->io_wq, io_cancel_task_cb, task, true);
                if (cret != IO_WQ_CANCEL_NOTFOUND)
@@ -8734,9 +8723,11 @@ static bool __io_uring_cancel_task_requests(struct io_ring_ctx *ctx,
 
                ret |= io_poll_remove_all(ctx, task);
                ret |= io_kill_timeouts(ctx, task);
+               if (!ret)
+                       break;
+               io_run_task_work();
+               cond_resched();
        }
-
-       return ret;
 }
 
 static void io_disable_sqo_submit(struct io_ring_ctx *ctx)
@@ -8771,11 +8762,10 @@ static void io_uring_cancel_task_requests(struct io_ring_ctx *ctx,
 
        io_cancel_defer_files(ctx, task, files);
        io_cqring_overflow_flush(ctx, true, task, files);
+       io_uring_cancel_files(ctx, task, files);
 
-       while (__io_uring_cancel_task_requests(ctx, task, files)) {
-               io_run_task_work();
-               cond_resched();
-       }
+       if (!files)
+               __io_uring_cancel_task_requests(ctx, task);
 
        if ((ctx->flags & IORING_SETUP_SQPOLL) && ctx->sq_data) {
                atomic_dec(&task->io_uring->in_idle);