io_uring: feed reqs back into alloc cache

Make io_req_free_batch(), which is used for inline executed requests and
IOPOLL, to return requests back into the allocation cache, so avoid
most of kmalloc()/kfree() for those cases.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Pavel Begunkov 2021-02-10 00:03:18 +00:00 committed by Jens Axboe
parent bf019da7fc
commit 6ff119a6e4

View file

@ -266,7 +266,7 @@ struct io_sq_data {
#define IO_IOPOLL_BATCH 8
#define IO_COMPL_BATCH 32
#define IO_REQ_CACHE_SIZE 8
#define IO_REQ_CACHE_SIZE 32
#define IO_REQ_ALLOC_BATCH 8
struct io_comp_state {
@ -2264,7 +2264,8 @@ static void io_req_free_batch_finish(struct io_ring_ctx *ctx,
percpu_ref_put_many(&ctx->refs, rb->ctx_refs);
}
static void io_req_free_batch(struct req_batch *rb, struct io_kiocb *req)
static void io_req_free_batch(struct req_batch *rb, struct io_kiocb *req,
struct io_submit_state *state)
{
io_queue_next(req);
@ -2278,9 +2279,13 @@ static void io_req_free_batch(struct req_batch *rb, struct io_kiocb *req)
rb->ctx_refs++;
io_dismantle_req(req);
rb->reqs[rb->to_free++] = req;
if (unlikely(rb->to_free == ARRAY_SIZE(rb->reqs)))
__io_req_free_batch_flush(req->ctx, rb);
if (state->free_reqs != ARRAY_SIZE(state->reqs)) {
state->reqs[state->free_reqs++] = req;
} else {
rb->reqs[rb->to_free++] = req;
if (unlikely(rb->to_free == ARRAY_SIZE(rb->reqs)))
__io_req_free_batch_flush(req->ctx, rb);
}
}
static void io_submit_flush_completions(struct io_comp_state *cs,
@ -2305,7 +2310,7 @@ static void io_submit_flush_completions(struct io_comp_state *cs,
/* submission and completion refs */
if (refcount_sub_and_test(2, &req->refs))
io_req_free_batch(&rb, req);
io_req_free_batch(&rb, req, &ctx->submit_state);
}
io_req_free_batch_finish(ctx, &rb);
@ -2458,7 +2463,7 @@ static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events,
(*nr_events)++;
if (refcount_dec_and_test(&req->refs))
io_req_free_batch(&rb, req);
io_req_free_batch(&rb, req, &ctx->submit_state);
}
io_commit_cqring(ctx);