Re: [PATCH 10/18] io_uring: batch io_kiocb allocation
flat view
From: Christoph Hellwig <hch@lst.de>
Date: 2019-01-29 17:26:29
Also in:
linux-block, linux-man
quoted hunk ↗ jump to hunk
-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) { + gfp_t gfp = GFP_ATOMIC | __GFP_NOWARN;
No actually in this patch, but why do we do GFP_ATOMIC allocations here? We aren't in irq context or under a spinlock.
+ if (!state) + req = kmem_cache_alloc(req_cachep, gfp);
Add a if (!req) goto out; plus the missing braces here..
quoted hunk ↗ jump to hunk
+ 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, sz, + state->reqs); + if (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++; + } + if (req) { req->ctx = ctx; req->flags = 0; return req; }
... and we don't need this conditional, which would otherwise also be in the fast path. -- 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: <a href=mailto:"aart@kvack.org">aart@kvack.org</a>