[PATCH v3 tip/core/locking 0/3] Memory-barrier documentation updates

From: Paul E. McKenney
Date: Fri Nov 22 2013 - 14:27:13 EST


Hello!

This series applies some long-needed updates to memory-barriers.txt:

1. Add ACCESS_ONCE() calls where needed to ensure their inclusion
in code copy-and-pasted from this file.

2. Add long atomic examples alongside the existing atomics.

3. Prohibit architectures supporting the Linux kernel from
speculating stores.

Changes from v2:

o Update examples so that that load against which the subsequent
store is to be ordered is part of the "if" condition.

o Add an example showing how the compiler can remove "if"
conditions and how to prevent it from doing so.

o Add ACCESS_ONCE() to the compiler-barrier section.

o Add a sentence noting that transitivity requires smp_mb().

Changes from v1:

o Combined with Peter Zijlstra's speculative-store-prohibition patch.

o Added more pitfalls to avoid when prohibiting speculative
stores, along with how to avoid them.

o Applied Josh Triplett's review comments.

Thanx, Paul

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/