Commit e5598d6a authored by Pavel Begunkov's avatar Pavel Begunkov Committed by Jens Axboe
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io_uring: compact SQ/CQ heads/tails 



Queues heads and tails cache line aligned. That makes sq, cq taking 4
lines or 5 lines if we include the rest of struct io_rings (e.g.
sq_flags is frequently accessed).

Since modern io_uring is mostly single threaded, it doesn't make much
send to spread them as such, it wastes space and puts additional pressure
on caches. Put them all into a single line.

Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/9c8deddf9a7ed32069235a530d1e117fb460bc4c.1692916914.git.asml.silence@gmail.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 093a650b

include/linux/io_uring_types.h

+2 −2
Original line number Diff line number Diff line
@@ -69,8 +69,8 @@ struct io_uring_task { 
};



struct io_uring {

	u32 head ____cacheline_aligned_in_smp;

	u32 tail ____cacheline_aligned_in_smp;

	u32 head;

	u32 tail;

};



/*