[tip:locking/core] Documentation/memory-barriers.txt: Cross-reference "tools/memory-model/"

[tip-bot for Andrea Parri]

Commit-ID:  621df431b0ac931e318679f54047c47eb23cfdd2
Gitweb:     https://git.kernel.org/tip/621df431b0ac931e318679f54047c47eb23cfdd2
Author:     Andrea Parri <parri.andrea@xxxxxxxxx>
AuthorDate: Tue, 20 Feb 2018 15:25:07 -0800
Committer:  Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Wed, 21 Feb 2018 09:58:14 +0100

Documentation/memory-barriers.txt: Cross-reference "tools/memory-model/"

A memory consistency model is now available for the Linux kernel [1],
which "can (roughly speaking) be thought of as an automated version of
memory-barriers.txt" and which is (in turn) "accompanied by extensive
documentation on its use and its design".

Inform the (occasional) reader of memory-barriers.txt of these
developments.

[1] https://marc.info/?l=linux-kernel&m=151687290114799&w=2

Co-developed-by: Andrea Parri <parri.andrea@xxxxxxxxx>
Co-developed-by: Akira Yokosawa <akiyks@xxxxxxxxx>
Signed-off-by: Andrea Parri <parri.andrea@xxxxxxxxx>
Signed-off-by: Akira Yokosawa <akiyks@xxxxxxxxx>
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
Acked-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: boqun.feng@xxxxxxxxx
Cc: dhowells@xxxxxxxxxx
Cc: j.alglave@xxxxxxxxx
Cc: linux-arch@xxxxxxxxxxxxxxx
Cc: luc.maranget@xxxxxxxx
Cc: nborisov@xxxxxxxx
Cc: npiggin@xxxxxxxxx
Cc: stern@xxxxxxxxxxxxxxxxxxx
Cc: will.deacon@xxxxxxx
Link: http://lkml.kernel.org/r/1519169112-20593-7-git-send-email-paulmck@xxxxxxxxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
 Documentation/memory-barriers.txt | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/Documentation/memory-barriers.txt b/Documentation/memory-barriers.txt
index a863009..a37d3af 100644
--- a/Documentation/memory-barriers.txt
+++ b/Documentation/memory-barriers.txt
@@ -14,7 +14,11 @@ DISCLAIMER
 This document is not a specification; it is intentionally (for the sake of
 brevity) and unintentionally (due to being human) incomplete. This document is
 meant as a guide to using the various memory barriers provided by Linux, but
-in case of any doubt (and there are many) please ask.
+in case of any doubt (and there are many) please ask.  Some doubts may be
+resolved by referring to the formal memory consistency model and related
+documentation at tools/memory-model/.  Nevertheless, even this memory
+model should be viewed as the collective opinion of its maintainers rather
+than as an infallible oracle.
 
 To repeat, this document is not a specification of what Linux expects from
 hardware.