leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

io_uring: simplify io_resubmit_prep()

Browse Source 
If not for async_data NULL check, io_resubmit_prep() is already an rw
specific version of io_req_prep_async(), but slower because 1) it always
goes through io_import_iovec() even if following io_setup_async_rw() the
result 2) instead of initialising iovec/iter in-place it does it
on-stack and then copies with io_setup_async_rw().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Pavel Begunkov 2021-02-28 22:35:20 +00:00 committed by Jens Axboe
parent b7e298d265
commit 179ae0d15e
1 changed files with 3 additions and 34 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

37
fs/io_uring.c
View File

@ -1032,14 +1032,10 @@ static struct file *io_file_get(struct io_submit_state *state,
static void __io_queue_sqe(struct io_kiocb *req);
static void io_rsrc_put_work(struct work_struct *work);
static int io_import_iovec(int rw, struct io_kiocb *req, struct iovec **iovec,
struct iov_iter *iter, bool needs_lock);
static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
const struct iovec *fast_iov,
struct iov_iter *iter, bool force);
static void io_req_task_queue(struct io_kiocb *req);
static void io_submit_flush_completions(struct io_comp_state *cs,
struct io_ring_ctx *ctx);
static int io_req_prep_async(struct io_kiocb *req);
static struct kmem_cache *req_cachep;
@ -2429,35 +2425,8 @@ static void kiocb_end_write(struct io_kiocb *req)
#ifdef CONFIG_BLOCK
static bool io_resubmit_prep(struct io_kiocb *req)
{
struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
int rw, ret;
struct iov_iter iter;
/* already prepared */
if (req->async_data)
return true;
switch (req->opcode) {
case IORING_OP_READV:
case IORING_OP_READ_FIXED:
case IORING_OP_READ:
rw = READ;
break;
case IORING_OP_WRITEV:
case IORING_OP_WRITE_FIXED:
case IORING_OP_WRITE:
rw = WRITE;
break;
default:
printk_once(KERN_WARNING "io_uring: bad opcode in resubmit %d\n",
req->opcode);
return false;
}
ret = io_import_iovec(rw, req, &iovec, &iter, false);
if (ret < 0)
return false;
return !io_setup_async_rw(req, iovec, inline_vecs, &iter, false);
/* either already prepared or successfully done */
return req->async_data || !io_req_prep_async(req);
}
static bool io_rw_should_reissue(struct io_kiocb *req)