diff options
| author | Roman Penyaev <rpenyaev@suse.de> | 2019-05-27 21:05:09 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2019-05-27 14:54:14 -0600 |
| commit | df23d2dec286697dd73568faf142466e8067844a (patch) | |
| tree | 7562ea83aeb3a5e22c6f04b8257b03167c540fe8 | |
| parent | d1432b199a541f3ef2e49778fc05a5f5e251a96d (diff) | |
liburing,queue,setup: handle IORING_SQ_NEED_WAKEUP for io_uring_submit()
Enter kernel only if SQ thread is off or wakeup is needed.
Signed-off-by: Roman Penyaev <rpenyaev@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | src/liburing.h | 1 | ||||
| -rw-r--r-- | src/queue.c | 26 | ||||
| -rw-r--r-- | src/setup.c | 4 |
3 files changed, 26 insertions, 5 deletions
diff --git a/src/liburing.h b/src/liburing.h index 2651b3d..ccefc40 100644 --- a/src/liburing.h +++ b/src/liburing.h @@ -46,6 +46,7 @@ struct io_uring_cq { struct io_uring { struct io_uring_sq sq; struct io_uring_cq cq; + unsigned flags; int ring_fd; }; diff --git a/src/queue.c b/src/queue.c index 5bbb279..eec26c9 100644 --- a/src/queue.c +++ b/src/queue.c @@ -63,6 +63,17 @@ int io_uring_wait_cqe(struct io_uring *ring, struct io_uring_cqe **cqe_ptr) } /* + * Returns true if we're not using SQ thread (thus nobody submits but us) + * or if IORING_SQ_NEED_WAKEUP is set, so dormouse should be explicitly + * awekened. + */ +static inline int sq_ring_needs_enter(struct io_uring *ring) +{ + return !(ring->flags & IORING_SETUP_SQPOLL) || + (*ring->sq.kflags & IORING_SQ_NEED_WAKEUP); +} + +/* * Submit sqes acquired from io_uring_get_sqe() to the kernel. * * Returns number of sqes submitted @@ -125,10 +136,17 @@ int io_uring_submit(struct io_uring *ring) } submit: - ret = io_uring_enter(ring->ring_fd, submitted, 0, - IORING_ENTER_GETEVENTS, NULL); - if (ret < 0) - return -errno; + if (sq_ring_needs_enter(ring)) { + unsigned flags = 0; + + if ((*ring->sq.kflags & IORING_SQ_NEED_WAKEUP)) + flags |= IORING_ENTER_SQ_WAKEUP; + + ret = io_uring_enter(ring->ring_fd, submitted, 0, flags, NULL); + if (ret < 0) + return -errno; + } else + ret = submitted; return ret; } diff --git a/src/setup.c b/src/setup.c index 73f35de..9da3c19 100644 --- a/src/setup.c +++ b/src/setup.c @@ -69,8 +69,10 @@ int io_uring_queue_mmap(int fd, struct io_uring_params *p, struct io_uring *ring memset(ring, 0, sizeof(*ring)); ret = io_uring_mmap(fd, p, &ring->sq, &ring->cq); - if (!ret) + if (!ret) { + ring->flags = p->flags; ring->ring_fd = fd; + } return ret; } |