Commit 730c3ed4 authored by Paul E. McKenney's avatar Paul E. McKenney Committed by Frederic Weisbecker
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refscale: Fix misplaced data re-read 



This commit fixes a misplaced data re-read in the typesafe code.
The reason that this was not noticed is that this is a performance test
with no writers, so a mismatch could not occur.

Signed-off-by: default avatarPaul E. McKenney <paulmck@kernel.org>
Signed-off-by: default avatarFrederic Weisbecker <frederic@kernel.org>
parent 0bb80ecc

kernel/rcu/refscale.c

+1 −1
Original line number Diff line number Diff line
@@ -655,12 +655,12 @@ static void typesafe_delay_section(const int nloops, const int udl, const int nd 
			goto retry;

		}

		un_delay(udl, ndl);

		b = READ_ONCE(rtsp->a);

		// Remember, seqlock read-side release can fail.

		if (!rts_release(rtsp, start)) {

			rcu_read_unlock();

			goto retry;

		}

		b = READ_ONCE(rtsp->a);

		WARN_ONCE(a != b, "Re-read of ->a changed from %u to %u.\n", a, b);

		b = rtsp->b;

		rcu_read_unlock();