io_uring: unify files and task cancel

Now __io_uring_cancel() and __io_uring_files_cancel() are very similar
and mostly differ by how we count requests, merge them and allow
tctx_inflight() to handle counting.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/1a5986a97df4dc1378f3fe0ca1eb483dbcf42112.1618101759.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 99d617c..8e2a0f9 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -8920,13 +8920,10 @@ static void io_uring_clean_tctx(struct io_uring_task *tctx)
        }
 }
 
-static s64 tctx_inflight_tracked(struct io_uring_task *tctx)
-{
-       return atomic_read(&tctx->inflight_tracked);
-}
-
-static s64 tctx_inflight(struct io_uring_task *tctx)
+static s64 tctx_inflight(struct io_uring_task *tctx, bool tracked)
 {
+       if (tracked)
+               return atomic_read(&tctx->inflight_tracked);
        return percpu_counter_sum(&tctx->inflight);
 }
 
@@ -8993,7 +8990,7 @@ static void io_uring_cancel_sqpoll(struct io_ring_ctx *ctx)
        atomic_inc(&tctx->in_idle);
        do {
                /* read completions before cancelations */
-               inflight = tctx_inflight(tctx);
+               inflight = tctx_inflight(tctx, false);
                if (!inflight)
                        break;
                io_uring_try_cancel_requests(ctx, current, NULL);
@@ -9004,43 +9001,18 @@ static void io_uring_cancel_sqpoll(struct io_ring_ctx *ctx)
                 * avoids a race where a completion comes in before we did
                 * prepare_to_wait().
                 */
-               if (inflight == tctx_inflight(tctx))
+               if (inflight == tctx_inflight(tctx, false))
                        schedule();
                finish_wait(&tctx->wait, &wait);
        } while (1);
        atomic_dec(&tctx->in_idle);
 }
 
-void __io_uring_files_cancel(struct files_struct *files)
-{
-       struct io_uring_task *tctx = current->io_uring;
-       DEFINE_WAIT(wait);
-       s64 inflight;
-
-       /* make sure overflow events are dropped */
-       atomic_inc(&tctx->in_idle);
-       do {
-               /* read completions before cancelations */
-               inflight = tctx_inflight_tracked(tctx);
-               if (!inflight)
-                       break;
-               io_uring_try_cancel(files);
-
-               prepare_to_wait(&tctx->wait, &wait, TASK_UNINTERRUPTIBLE);
-               if (inflight == tctx_inflight_tracked(tctx))
-                       schedule();
-               finish_wait(&tctx->wait, &wait);
-       } while (1);
-       atomic_dec(&tctx->in_idle);
-
-       io_uring_clean_tctx(tctx);
-}
-
 /*
  * Find any io_uring fd that this task has registered or done IO on, and cancel
  * requests.
  */
-void __io_uring_task_cancel(void)
+void __io_uring_cancel(struct files_struct *files)
 {
        struct io_uring_task *tctx = current->io_uring;
        DEFINE_WAIT(wait);
@@ -9048,15 +9020,14 @@ void __io_uring_task_cancel(void)
 
        /* make sure overflow events are dropped */
        atomic_inc(&tctx->in_idle);
-       __io_uring_files_cancel(NULL);
+       io_uring_try_cancel(files);
 
        do {
                /* read completions before cancelations */
-               inflight = tctx_inflight(tctx);
+               inflight = tctx_inflight(tctx, !!files);
                if (!inflight)
                        break;
-               io_uring_try_cancel(NULL);
-
+               io_uring_try_cancel(files);
                prepare_to_wait(&tctx->wait, &wait, TASK_UNINTERRUPTIBLE);
 
                /*
@@ -9064,16 +9035,17 @@ void __io_uring_task_cancel(void)
                 * avoids a race where a completion comes in before we did
                 * prepare_to_wait().
                 */
-               if (inflight == tctx_inflight(tctx))
+               if (inflight == tctx_inflight(tctx, !!files))
                        schedule();
                finish_wait(&tctx->wait, &wait);
        } while (1);
-
        atomic_dec(&tctx->in_idle);
 
        io_uring_clean_tctx(tctx);
-       /* all current's requests should be gone, we can kill tctx */
-       __io_uring_free(current);
+       if (!files) {
+               /* for exec all current's requests should be gone, kill tctx */
+               __io_uring_free(current);
+       }
 }
 
 static void *io_uring_validate_mmap_request(struct file *file,

diff --git a/include/linux/io_uring.h b/include/linux/io_uring.h
index 79cde99..04b650b 100644 (file)
--- a/include/linux/io_uring.h
+++ b/include/linux/io_uring.h
@@ -7,19 +7,17 @@
 
 #if defined(CONFIG_IO_URING)
 struct sock *io_uring_get_socket(struct file *file);
-void __io_uring_task_cancel(void);
-void __io_uring_files_cancel(struct files_struct *files);
+void __io_uring_cancel(struct files_struct *files);
 void __io_uring_free(struct task_struct *tsk);
 
-static inline void io_uring_task_cancel(void)
+static inline void io_uring_files_cancel(struct files_struct *files)
 {
        if (current->io_uring)
-               __io_uring_task_cancel();
+               __io_uring_cancel(files);
 }
-static inline void io_uring_files_cancel(struct files_struct *files)
+static inline void io_uring_task_cancel(void)
 {
-       if (current->io_uring)
-               __io_uring_files_cancel(files);
+       return io_uring_files_cancel(NULL);
 }
 static inline void io_uring_free(struct task_struct *tsk)
 {