From e1bb0f12b4d5d8f307e8594788935e9fcdbd41de Mon Sep 17 00:00:00 2001 From: Hristo Venev Date: Fri, 6 Sep 2019 19:10:14 +0100 Subject: liburing: Use the single mmap feature Signed-off-by: Hristo Venev --- src/setup.c | 35 ++++++++++++++++++++++++++--------- 1 file changed, 26 insertions(+), 9 deletions(-) diff --git a/src/setup.c b/src/setup.c index 47b0deb..48c96a0 100644 --- a/src/setup.c +++ b/src/setup.c @@ -16,10 +16,30 @@ static int io_uring_mmap(int fd, struct io_uring_params *p, int ret; sq->ring_sz = p->sq_off.array + p->sq_entries * sizeof(unsigned); + cq->ring_sz = p->cq_off.cqes + p->cq_entries * sizeof(struct io_uring_cqe); + + if (p->features & IORING_FEAT_SINGLE_MMAP) { + if (cq->ring_sz > sq->ring_sz) { + sq->ring_sz = cq->ring_sz; + } + cq->ring_sz = sq->ring_sz; + } sq->ring_ptr = mmap(0, sq->ring_sz, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, fd, IORING_OFF_SQ_RING); if (sq->ring_ptr == MAP_FAILED) return -errno; + + if (p->features & IORING_FEAT_SINGLE_MMAP) { + cq->ring_ptr = sq->ring_ptr; + } else { + cq->ring_ptr = mmap(0, cq->ring_sz, PROT_READ | PROT_WRITE, + MAP_SHARED | MAP_POPULATE, fd, IORING_OFF_CQ_RING); + if (cq->ring_ptr == MAP_FAILED) { + ret = -errno; + goto err; + } + } + sq->khead = sq->ring_ptr + p->sq_off.head; sq->ktail = sq->ring_ptr + p->sq_off.tail; sq->kring_mask = sq->ring_ptr + p->sq_off.ring_mask; @@ -34,19 +54,14 @@ static int io_uring_mmap(int fd, struct io_uring_params *p, IORING_OFF_SQES); if (sq->sqes == MAP_FAILED) { ret = -errno; + if (cq->ring_ptr != sq->ring_ptr) { + munmap(cq->ring_ptr, cq->ring_sz); + } err: munmap(sq->ring_ptr, sq->ring_sz); return ret; } - cq->ring_sz = p->cq_off.cqes + p->cq_entries * sizeof(struct io_uring_cqe); - cq->ring_ptr = mmap(0, cq->ring_sz, PROT_READ | PROT_WRITE, - MAP_SHARED | MAP_POPULATE, fd, IORING_OFF_CQ_RING); - if (cq->ring_ptr == MAP_FAILED) { - ret = -errno; - munmap(sq->sqes, *sq->kring_entries * sizeof(struct io_uring_sqe)); - goto err; - } cq->khead = cq->ring_ptr + p->cq_off.head; cq->ktail = cq->ring_ptr + p->cq_off.tail; cq->kring_mask = cq->ring_ptr + p->cq_off.ring_mask; @@ -105,6 +120,8 @@ void io_uring_queue_exit(struct io_uring *ring) munmap(sq->sqes, *sq->kring_entries * sizeof(struct io_uring_sqe)); munmap(sq->ring_ptr, sq->ring_sz); - munmap(cq->ring_ptr, cq->ring_sz); + if (cq->ring_ptr != sq->ring_ptr) { + munmap(cq->ring_ptr, cq->ring_sz); + } close(ring->ring_fd); } -- cgit