io_uring: fix wrong sequence setting logic

Sqo_thread will get sqring in batches, which will cause
ctx->cached_sq_head to be added in batches. if one of these
sqes is set with the DRAIN flag, then he will never get a
chance to process, and finally sqo_thread will not exit.

Fixes: de0617e467 ("io_uring: add support for marking commands as draining")
Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jackie Liu 2019-09-09 20:50:39 +08:00 committed by Jens Axboe
parent ac90f249e1
commit 8776f3fa15
1 changed files with 3 additions and 1 deletions

View File

@ -264,6 +264,7 @@ struct io_ring_ctx {
struct sqe_submit {
const struct io_uring_sqe *sqe;
unsigned short index;
u32 sequence;
bool has_user;
bool needs_lock;
bool needs_fixed_file;
@ -2016,7 +2017,7 @@ static int io_req_set_file(struct io_ring_ctx *ctx, const struct sqe_submit *s,
if (flags & IOSQE_IO_DRAIN) {
req->flags |= REQ_F_IO_DRAIN;
req->sequence = ctx->cached_sq_head - 1;
req->sequence = s->sequence;
}
if (!io_op_needs_file(s->sqe))
@ -2224,6 +2225,7 @@ static bool io_get_sqring(struct io_ring_ctx *ctx, struct sqe_submit *s)
if (head < ctx->sq_entries) {
s->index = head;
s->sqe = &ctx->sq_sqes[head];
s->sequence = ctx->cached_sq_head;
ctx->cached_sq_head++;
return true;
}