io_uring: optimise rsrc referencing

Apparently, percpu_ref_put/get() are expensive enough if done per
request, get them in a batch and cache on the submission side to avoid
getting it over and over again. Also, if we're completing under
uring_lock, return refs back into the cache instead of
perfcpu_ref_put(). Pretty similar to how we do tctx->cached_refs
accounting, but fall back to normal putting when we already changed a
rsrc node by the time of free.

Signed-off-by: Pavel Begunkov <[email protected]>
Link: https://lore.kernel.org/r/b40d8c5bc77d3c9550df8a319117a374ac85f8f4.1633817310.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <[email protected]>

0 files changed, 0 insertions, 0 deletions