io_uring: export io_put_task()

Make io_put_task() available to non-core parts of io_uring, we'll need
it for notification infrastructure.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/3686807d4c03b72e389947b0e8692d4d44334ef0.1657643355.git.asml.silence@gmail.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

include/linux/io_uring_types.h

@@ -4,6 +4,7 @@
 #include <linux/blkdev.h>
 #include <linux/task_work.h>
 #include <linux/bitmap.h>
+#include <linux/llist.h>
 #include <uapi/linux/io_uring.h>
 
 struct io_wq_work_node {
@@ -43,6 +44,30 @@ struct io_hash_table {
 	unsigned		hash_bits;
 };
 
+/*
+ * Arbitrary limit, can be raised if need be
+ */
+#define IO_RINGFD_REG_MAX 16
+
+struct io_uring_task {
+	/* submission side */
+	int				cached_refs;
+	const struct io_ring_ctx 	*last;
+	struct io_wq			*io_wq;
+	struct file			*registered_rings[IO_RINGFD_REG_MAX];
+
+	struct xarray			xa;
+	struct wait_queue_head		wait;
+	atomic_t			in_idle;
+	atomic_t			inflight_tracked;
+	struct percpu_counter		inflight;
+
+	struct { /* task_work */
+		struct llist_head	task_list;
+		struct callback_head	task_work;
+	} ____cacheline_aligned_in_smp;
+};
+
 struct io_uring {
 	u32 head ____cacheline_aligned_in_smp;
 	u32 tail ____cacheline_aligned_in_smp;

io_uring/io_uring.c

@@ -608,7 +608,7 @@ static bool io_cqring_overflow_flush(struct io_ring_ctx *ctx)
 	return ret;
 }
 
-static void __io_put_task(struct task_struct *task, int nr)
+void __io_put_task(struct task_struct *task, int nr)
 {
 	struct io_uring_task *tctx = task->io_uring;
 
@@ -618,15 +618,6 @@ static void __io_put_task(struct task_struct *task, int nr)
 	put_task_struct_many(task, nr);
 }
 
-/* must to be called somewhat shortly after putting a request */
-static inline void io_put_task(struct task_struct *task, int nr)
-{
-	if (likely(task == current))
-		task->io_uring->cached_refs += nr;
-	else
-		__io_put_task(task, nr);
-}
-
 static void io_task_refs_refill(struct io_uring_task *tctx)
 {
 	unsigned int refill = -tctx->cached_refs + IO_TCTX_REFS_CACHE_NR;

io_uring/io_uring.h

@@ -71,6 +71,7 @@ void io_wq_submit_work(struct io_wq_work *work);
 
 void io_free_req(struct io_kiocb *req);
 void io_queue_next(struct io_kiocb *req);
+void __io_put_task(struct task_struct *task, int nr);
 
 bool io_match_task_safe(struct io_kiocb *head, struct task_struct *task,
 			bool cancel_all);
@@ -258,4 +259,13 @@ static inline void io_commit_cqring_flush(struct io_ring_ctx *ctx)
 		__io_commit_cqring_flush(ctx);
 }
 
+/* must to be called somewhat shortly after putting a request */
+static inline void io_put_task(struct task_struct *task, int nr)
+{
+	if (likely(task == current))
+		task->io_uring->cached_refs += nr;
+	else
+		__io_put_task(task, nr);
+}
+
 #endif

io_uring/tctx.h

 // SPDX-License-Identifier: GPL-2.0
 
-#include <linux/llist.h>
-
-/*
- * Arbitrary limit, can be raised if need be
- */
-#define IO_RINGFD_REG_MAX 16
-
-struct io_uring_task {
-	/* submission side */
-	int				cached_refs;
-	const struct io_ring_ctx 	*last;
-	struct io_wq			*io_wq;
-	struct file			*registered_rings[IO_RINGFD_REG_MAX];
-
-	struct xarray			xa;
-	struct wait_queue_head		wait;
-	atomic_t			in_idle;
-	atomic_t			inflight_tracked;
-	struct percpu_counter		inflight;
-
-	struct { /* task_work */
-		struct llist_head	task_list;
-		struct callback_head	task_work;
-	} ____cacheline_aligned_in_smp;
-};
-
 struct io_tctx_node {
 	struct list_head	ctx_node;
 	struct task_struct	*task;