Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
io_uring/kbuf: remove legacy kbuf bulk allocation
Legacy provided buffers are slow and discouraged in favour of the ring
variant. Remove the bulk allocation to keep it simpler as we don't care
about performance.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/a064d70370e590efed8076e9501ae4cfc20fe0ca.1738724373.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
authored by
Pavel Begunkov
and committed by
Jens Axboe
7919292a
92a3bac9
+5
-25
+5
-25
io_uring/kbuf.c
+5
-25
io_uring/kbuf.c
···
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return 0;
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}
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-
#define IO_BUFFER_ALLOC_BATCH 64
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-
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static int io_refill_buffer_cache(struct io_ring_ctx *ctx)
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{
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-
struct io_buffer *bufs[IO_BUFFER_ALLOC_BATCH];
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int allocated;
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+
struct io_buffer *buf;
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/*
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* Completions that don't happen inline (eg not under uring_lock) will
···
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spin_unlock(&ctx->completion_lock);
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}
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-
/*
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* No free buffers and no completion entries either. Allocate a new
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* batch of buffer entries and add those to our freelist.
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*/
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-
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allocated = kmem_cache_alloc_bulk(io_buf_cachep, GFP_KERNEL_ACCOUNT,
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ARRAY_SIZE(bufs), (void **) bufs);
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if (unlikely(!allocated)) {
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/*
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* Bulk alloc is all-or-nothing. If we fail to get a batch,
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* retry single alloc to be on the safe side.
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*/
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bufs[0] = kmem_cache_alloc(io_buf_cachep, GFP_KERNEL);
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if (!bufs[0])
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return -ENOMEM;
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allocated = 1;
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}
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while (allocated)
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list_add_tail(&bufs[--allocated]->list, &ctx->io_buffers_cache);
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-
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buf = kmem_cache_alloc(io_buf_cachep, GFP_KERNEL);
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if (!buf)
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return -ENOMEM;
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list_add_tail(&buf->list, &ctx->io_buffers_cache);
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return 0;
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}
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