From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: [PATCH 10/18] io_uring: batch io_kiocb allocation Date: Wed, 30 Jan 2019 14:55:32 -0700 Message-ID: <20190130215540.20871-11-axboe@kernel.dk> References: <20190130215540.20871-1-axboe@kernel.dk> Return-path: In-Reply-To: <20190130215540.20871-1-axboe@kernel.dk> Sender: owner-linux-aio@kvack.org To: linux-aio@kvack.org, linux-block@vger.kernel.org, linux-api@vger.kernel.org Cc: hch@lst.de, jmoyer@redhat.com, avi@scylladb.com, jannh@google.com, Jens Axboe List-Id: linux-api@vger.kernel.org Similarly to how we use the state->ios_left to know how many references to get to a file, we can use it to allocate the io_kiocb's we need in bulk. Signed-off-by: Jens Axboe --- fs/io_uring.c | 45 ++++++++++++++++++++++++++++++++++++++------- 1 file changed, 38 insertions(+), 7 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 488c57a968af..3cd3d0720961 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -141,6 +141,13 @@ struct io_kiocb { struct io_submit_state { struct blk_plug plug; + /* + * io_kiocb alloc cache + */ + void *reqs[IO_IOPOLL_BATCH]; + unsigned int free_reqs; + unsigned int cur_req; + /* * File reference cache */ @@ -258,20 +265,40 @@ static void io_ring_drop_ctx_refs(struct io_ring_ctx *ctx, unsigned refs) wake_up(&ctx->wait); } -static struct io_kiocb *io_get_req(struct io_ring_ctx *ctx) +static struct io_kiocb *io_get_req(struct io_ring_ctx *ctx, + struct io_submit_state *state) { struct io_kiocb *req; if (!percpu_ref_tryget(&ctx->refs)) return NULL; - req = kmem_cache_alloc(req_cachep, __GFP_NOWARN); - if (req) { - req->ctx = ctx; - req->flags = 0; - return req; + if (!state) { + req = kmem_cache_alloc(req_cachep, __GFP_NOWARN); + if (unlikely(!req)) + goto out; + } else if (!state->free_reqs) { + size_t sz; + int ret; + + sz = min_t(size_t, state->ios_left, ARRAY_SIZE(state->reqs)); + ret = kmem_cache_alloc_bulk(req_cachep, __GFP_NOWARN, sz, + state->reqs); + if (unlikely(ret <= 0)) + goto out; + state->free_reqs = ret - 1; + state->cur_req = 1; + req = state->reqs[0]; + } else { + req = state->reqs[state->cur_req]; + state->free_reqs--; + state->cur_req++; } + req->ctx = ctx; + req->flags = 0; + return req; +out: io_ring_drop_ctx_refs(ctx, 1); return NULL; } @@ -910,7 +937,7 @@ static int io_submit_sqe(struct io_ring_ctx *ctx, const struct sqe_submit *s, if (unlikely(s->sqe->flags)) return -EINVAL; - req = io_get_req(ctx); + req = io_get_req(ctx, state); if (unlikely(!req)) return -EAGAIN; @@ -934,6 +961,9 @@ static void io_submit_state_end(struct io_submit_state *state) { blk_finish_plug(&state->plug); io_file_put(state, NULL); + if (state->free_reqs) + kmem_cache_free_bulk(req_cachep, state->free_reqs, + &state->reqs[state->cur_req]); } /* @@ -943,6 +973,7 @@ static void io_submit_state_start(struct io_submit_state *state, struct io_ring_ctx *ctx, unsigned max_ios) { blk_start_plug(&state->plug); + state->free_reqs = 0; state->file = NULL; state->ios_left = max_ios; } -- 2.17.1 -- To unsubscribe, send a message with 'unsubscribe linux-aio' in the body to majordomo@kvack.org. For more info on Linux AIO, see: http://www.kvack.org/aio/ Don't email: aart@kvack.org