From: Dylan Yudaken <dylany@fb.com>
To: Jens Axboe <axboe@kernel.dk>,
Pavel Begunkov <asml.silence@gmail.com>,
<io-uring@vger.kernel.org>
Cc: <kernel-team@fb.com>, Dylan Yudaken <dylany@fb.com>
Subject: [PATCH v3 1/4] io_uring: remove duplicated calls to io_kiocb_ppos
Date: Tue, 22 Feb 2022 02:55:01 -0800 [thread overview]
Message-ID: <20220222105504.3331010-2-dylany@fb.com> (raw)
In-Reply-To: <20220222105504.3331010-1-dylany@fb.com>
io_kiocb_ppos is called in both branches, and it seems that the compiler
does not fuse this. Fusing removes a few bytes from loop_rw_iter.
Before:
$ nm -S fs/io_uring.o | grep loop_rw_iter
0000000000002430 0000000000000124 t loop_rw_iter
After:
$ nm -S fs/io_uring.o | grep loop_rw_iter
0000000000002430 000000000000010d t loop_rw_iter
Signed-off-by: Dylan Yudaken <dylany@fb.com>
---
fs/io_uring.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 77b9c7e4793b..1f9b4466c269 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -3400,6 +3400,7 @@ static ssize_t loop_rw_iter(int rw, struct io_kiocb *req, struct iov_iter *iter)
struct kiocb *kiocb = &req->rw.kiocb;
struct file *file = req->file;
ssize_t ret = 0;
+ loff_t *ppos;
/*
* Don't support polled IO through this interface, and we can't
@@ -3412,6 +3413,8 @@ static ssize_t loop_rw_iter(int rw, struct io_kiocb *req, struct iov_iter *iter)
!(kiocb->ki_filp->f_flags & O_NONBLOCK))
return -EAGAIN;
+ ppos = io_kiocb_ppos(kiocb);
+
while (iov_iter_count(iter)) {
struct iovec iovec;
ssize_t nr;
@@ -3425,10 +3428,10 @@ static ssize_t loop_rw_iter(int rw, struct io_kiocb *req, struct iov_iter *iter)
if (rw == READ) {
nr = file->f_op->read(file, iovec.iov_base,
- iovec.iov_len, io_kiocb_ppos(kiocb));
+ iovec.iov_len, ppos);
} else {
nr = file->f_op->write(file, iovec.iov_base,
- iovec.iov_len, io_kiocb_ppos(kiocb));
+ iovec.iov_len, ppos);
}
if (nr < 0) {
--
2.30.2
next prev parent reply other threads:[~2022-02-22 10:55 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-22 10:55 [PATCH v3 0/4] io_uring: consistent behaviour with linked read/write Dylan Yudaken
2022-02-22 10:55 ` Dylan Yudaken [this message]
2022-02-23 23:06 ` [PATCH v3 1/4] io_uring: remove duplicated calls to io_kiocb_ppos Pavel Begunkov
2022-02-22 10:55 ` [PATCH v3 2/4] io_uring: update kiocb->ki_pos at execution time Dylan Yudaken
2022-02-23 23:06 ` Pavel Begunkov
2022-02-22 10:55 ` [PATCH v3 3/4] io_uring: do not recalculate ppos unnecessarily Dylan Yudaken
2022-02-23 23:07 ` Pavel Begunkov
2022-02-22 10:55 ` [PATCH v3 4/4] io_uring: pre-increment f_pos on rw Dylan Yudaken
2022-02-23 23:51 ` [PATCH v3 0/4] io_uring: consistent behaviour with linked read/write Jens Axboe
2022-02-24 10:45 ` Dylan Yudaken
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