From 9ad3c143d7d6942c66f27bc6c18f5df638f70aff Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 27 Nov 2017 09:20:40 -0800 Subject: doc: De-emphasize smp_read_barrier_depends This commit keeps only the historical and low-level discussion of smp_read_barrier_depends(). Signed-off-by: Paul E. McKenney [ paulmck: Adjusted to allow for David Howells feedback on prior commit. ] --- Documentation/RCU/Design/Requirements/Requirements.html | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'Documentation/RCU/Design/Requirements') diff --git a/Documentation/RCU/Design/Requirements/Requirements.html b/Documentation/RCU/Design/Requirements/Requirements.html index 62e847bcdcdd..571c3d75510f 100644 --- a/Documentation/RCU/Design/Requirements/Requirements.html +++ b/Documentation/RCU/Design/Requirements/Requirements.html @@ -581,7 +581,8 @@ This guarantee was only partially premeditated. DYNIX/ptx used an explicit memory barrier for publication, but had nothing resembling rcu_dereference() for subscription, nor did it have anything resembling the smp_read_barrier_depends() -that was later subsumed into rcu_dereference(). +that was later subsumed into rcu_dereference() and later +still into READ_ONCE(). The need for these operations made itself known quite suddenly at a late-1990s meeting with the DEC Alpha architects, back in the days when DEC was still a free-standing company. -- cgit v1.2.3