| Message ID | 20190713035826.2987-1-liuzhengyuan@kylinos.cn (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/2] io_uring: make req from defer and link list not touch async list | expand |
On 7/12/19 9:58 PM, Zhengyuan Liu wrote: > We would queue a work for each req in defer and link list without > increasing async->cnt, so we shouldn't decrease it while exiting > from workqueue as well as shouldn't process the req in async list. Took a closer look at this one. First comment, can you rewrite the subject line? I honestly don't quite know what that is trying to say. Apart from that: > diff --git a/fs/io_uring.c b/fs/io_uring.c > index 7e932c572f26..3e48fd7cd08f 100644 > --- a/fs/io_uring.c > +++ b/fs/io_uring.c > @@ -333,7 +333,8 @@ struct io_kiocb { > #define REQ_F_IO_DRAIN 16 /* drain existing IO first */ > #define REQ_F_IO_DRAINED 32 /* drain done */ > #define REQ_F_LINK 64 /* linked sqes */ > -#define REQ_F_FAIL_LINK 128 /* fail rest of links */ > +#define REQ_F_LINKED 128 /* linked sqes done */ > +#define REQ_F_FAIL_LINK 256 /* fail rest of links */ _LINKED is poorly chosen, hard to know what the difference between _LINK and _LINKED is here, they seem identical. Please rename it to _LINK_DONE or something like that. Thanks!
diff --git a/fs/io_uring.c b/fs/io_uring.c index 7e932c572f26..3e48fd7cd08f 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -333,7 +333,8 @@ struct io_kiocb { #define REQ_F_IO_DRAIN 16 /* drain existing IO first */ #define REQ_F_IO_DRAINED 32 /* drain done */ #define REQ_F_LINK 64 /* linked sqes */ -#define REQ_F_FAIL_LINK 128 /* fail rest of links */ +#define REQ_F_LINKED 128 /* linked sqes done */ +#define REQ_F_FAIL_LINK 256 /* fail rest of links */ u64 user_data; u32 result; u32 sequence; @@ -630,6 +631,7 @@ static void io_req_link_next(struct io_kiocb *req) nxt->flags |= REQ_F_LINK; } + nxt->flags |= REQ_F_LINKED; INIT_WORK(&nxt->work, io_sq_wq_submit_work); queue_work(req->ctx->sqo_wq, &nxt->work); } @@ -1845,6 +1847,10 @@ static void io_sq_wq_submit_work(struct work_struct *work) /* async context always use a copy of the sqe */ kfree(sqe); + /* req from defer and link list needn't dec async_list->cnt */ + if (req->flags & (REQ_F_IO_DRAINED | REQ_F_LINKED)) + goto out; + if (!async_list) break; if (!list_empty(&req_list)) { @@ -1892,6 +1898,7 @@ static void io_sq_wq_submit_work(struct work_struct *work) } } +out: if (cur_mm) { set_fs(old_fs); unuse_mm(cur_mm);
We would queue a work for each req in defer and link list without increasing async->cnt, so we shouldn't decrease it while exiting from workqueue as well as shouldn't process the req in async list. Signed-off-by: Zhengyuan Liu <liuzhengyuan@kylinos.cn> --- fs/io_uring.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)