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| author | Pavel Begunkov <asml.silence@gmail.com> | 2021-03-22 01:58:33 +0000 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2021-04-11 17:41:59 -0600 |
| commit | ab454438aa8dc9eb113df7d00f2cf9ec628a26ce (patch) | |
| tree | 90831c56d6cb0456a640b8c34e21b6962d6ef4b5 /fs/io_uring.c | |
| parent | 8c130827f417da791edb919df8cac56af30a1489 (diff) | |
| download | lwn-ab454438aa8dc9eb113df7d00f2cf9ec628a26ce.tar.gz lwn-ab454438aa8dc9eb113df7d00f2cf9ec628a26ce.zip | |
io_uring: hide iter revert in resubmit_prep
Move iov_iter_revert() resetting iterator in case of -EIOCBQUEUED into
io_resubmit_prep(), so we don't do heavy revert in hot path, also saves
a couple of checks.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'fs/io_uring.c')
| -rw-r--r-- | fs/io_uring.c | 17 |
1 files changed, 8 insertions, 9 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index 9362c9228540..a7239c86326e 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -2445,8 +2445,13 @@ static void kiocb_end_write(struct io_kiocb *req) #ifdef CONFIG_BLOCK static bool io_resubmit_prep(struct io_kiocb *req) { - /* either already prepared or successfully done */ - return req->async_data || !io_req_prep_async(req); + struct io_async_rw *rw = req->async_data; + + if (!rw) + return !io_req_prep_async(req); + /* may have left rw->iter inconsistent on -EIOCBQUEUED */ + iov_iter_revert(&rw->iter, req->result - iov_iter_count(&rw->iter)); + return true; } static bool io_rw_should_reissue(struct io_kiocb *req) @@ -2505,14 +2510,8 @@ static void io_complete_rw_iopoll(struct kiocb *kiocb, long res, long res2) struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb); #ifdef CONFIG_BLOCK - /* Rewind iter, if we have one. iopoll path resubmits as usual */ if (res == -EAGAIN && io_rw_should_reissue(req)) { - struct io_async_rw *rw = req->async_data; - - if (rw) - iov_iter_revert(&rw->iter, - req->result - iov_iter_count(&rw->iter)); - else if (!io_resubmit_prep(req)) + if (!io_resubmit_prep(req)) req->flags |= REQ_F_DONT_REISSUE; } #endif |