[PATCH] io_uring: simplify file ref tracking in subm state

[PATCH] io_uring: simplify file ref tracking in subm state

[Pavel Begunkov]

Currently, file refs in struct io_submit_state are tracked with 2 vars:
@has_refs -- how many refs were initially taken
@used_refs -- number of refs used

Replace it with a single veriable counting how many refs left at the
current moment.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 fs/io_uring.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index e4ffb9c3f04d..644e5727389c 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -706,7 +706,6 @@ struct io_submit_state {
 	struct file		*file;
 	unsigned int		fd;
 	unsigned int		has_refs;
-	unsigned int		used_refs;
 	unsigned int		ios_left;
 };
 
@@ -2332,10 +2331,8 @@ static void io_iopoll_req_issued(struct io_kiocb *req)
 
 static void __io_state_file_put(struct io_submit_state *state)
 {
-	int diff = state->has_refs - state->used_refs;
-
-	if (diff)
-		fput_many(state->file, diff);
+	if (state->has_refs)
+		fput_many(state->file, state->has_refs);
 	state->file = NULL;
 }
 
@@ -2357,7 +2354,7 @@ static struct file *__io_file_get(struct io_submit_state *state, int fd)
 
 	if (state->file) {
 		if (state->fd == fd) {
-			state->used_refs++;
+			state->has_refs--;
 			state->ios_left--;
 			return state->file;
 		}
@@ -2368,9 +2365,8 @@ static struct file *__io_file_get(struct io_submit_state *state, int fd)
 		return NULL;
 
 	state->fd = fd;
-	state->has_refs = state->ios_left;
-	state->used_refs = 1;
 	state->ios_left--;
+	state->has_refs = state->ios_left;
 	return state->file;
 }
 
-- 
2.24.0

Re: [PATCH] io_uring: simplify file ref tracking in subm state

[Jens Axboe]

On 7/16/20 2:28 PM, Pavel Begunkov wrote:
> Currently, file refs in struct io_submit_state are tracked with 2 vars:
> @has_refs -- how many refs were initially taken
> @used_refs -- number of refs used
> 
> Replace it with a single veriable counting how many refs left at the
> current moment.

Applied, thanks.

-- 
Jens Axboe