56 lines
1.7 KiB
Diff
56 lines
1.7 KiB
Diff
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From 30cdb8d7d06f51bb86142c537ea05bd01c31bb40 Mon Sep 17 00:00:00 2001
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From: Christian Loehle <christian.loehle@arm.com>
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Date: Thu, 5 Sep 2024 10:26:45 +0100
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Subject: io_uring: Do not set iowait before sleeping
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Setting in_iowait was introduced in commit
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8a796565cec3 ("io_uring: Use io_schedule* in cqring wait")
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to tackle a perf regression that was caused by menu taking iowait into
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account for synchronous IO and thus not selecting deeper states like in
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the io_uring counterpart.
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That behaviour is gone, so the workaround can be removed.
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Signed-off-by: Christian Loehle <christian.loehle@arm.com>
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---
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io_uring/io_uring.c | 17 -----------------
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1 file changed, 17 deletions(-)
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--- a/io_uring/io_uring.c
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+++ b/io_uring/io_uring.c
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@@ -2359,15 +2359,6 @@ int io_run_task_work_sig(struct io_ring_
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return 0;
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}
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-static bool current_pending_io(void)
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-{
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- struct io_uring_task *tctx = current->io_uring;
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-
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- if (!tctx)
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- return false;
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- return percpu_counter_read_positive(&tctx->inflight);
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-}
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-
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/* when returns >0, the caller should retry */
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static inline int io_cqring_wait_schedule(struct io_ring_ctx *ctx,
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struct io_wait_queue *iowq)
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@@ -2385,19 +2376,11 @@ static inline int io_cqring_wait_schedul
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if (unlikely(io_should_wake(iowq)))
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return 0;
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- /*
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- * Mark us as being in io_wait if we have pending requests, so cpufreq
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- * can take into account that the task is waiting for IO - turns out
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- * to be important for low QD IO.
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- */
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- if (current_pending_io())
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- current->in_iowait = 1;
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ret = 0;
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if (iowq->timeout == KTIME_MAX)
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schedule();
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else if (!schedule_hrtimeout(&iowq->timeout, HRTIMER_MODE_ABS))
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ret = -ETIME;
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- current->in_iowait = 0;
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return ret;
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}
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