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From:   "Pavel Begunkov (Silence)" <asml.silence@gmail.com>
To:     Jens Axboe <axboe@kernel.dk>, Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org
Cc:     Pavel Begunkov <asml.silence@gmail.com>
Subject: [RFC PATCH 0/2] Optimise io_uring completion waiting
Date:   Sat, 14 Sep 2019 01:28:00 +0300
Message-Id: <cover.1568413210.git.asml.silence@gmail.com>
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From: Pavel Begunkov <asml.silence@gmail.com>

There could be a lot of overhead within generic wait_event_*() used for
waiting for large number of completions. The patchset removes much of
it by using custom wait event (wait_threshold).

Synthetic test showed ~40% performance boost. (see patch 2)

Pavel Begunkov (2):
  sched/wait: Add wait_threshold
  io_uring: Optimise cq waiting with wait_threshold

 fs/io_uring.c                  | 21 ++++++-----
 include/linux/wait_threshold.h | 64 ++++++++++++++++++++++++++++++++++
 kernel/sched/Makefile          |  2 +-
 kernel/sched/wait_threshold.c  | 26 ++++++++++++++
 4 files changed, 103 insertions(+), 10 deletions(-)
 create mode 100644 include/linux/wait_threshold.h
 create mode 100644 kernel/sched/wait_threshold.c

-- 
2.22.0