Hello, Ingo, This pull request contains additions to the memory-barrier documentation, along with a downgrading of UNLOCK+LOCK to no longer be a full memory barrier, and finally an smp_mb__after_unlock_lock() that allows upgrading a particular LOCK to pair with a preceding UNLOCK to form a full memory barrier, and application of smp_mb__after_unlock_lock() to RCU. The first four documentation commits are ready for 3.14: b145f8acfd82 (Add needed ACCESS_ONCE() calls to memory-barriers.txt) 6be08d626389 (Add long atomic examples to memory-barriers.txt) c89bb78cfbe1 (Prohibit speculative writes) b2ba08be67fc (Document ACCESS_ONCE()) The remaining commits might or might not be, but are at a point where getting them into -tip is appropriate given other changes in this area, e.g., Peter's smp_load_acquire() and smp_store_release(). These changes are available in the git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git locking/mb for you to fetch changes up to 9f9df17e265b2c5aea11a95e3e69269d005ac0ae: powerpc: Full barrier for smp_mb__after_unlock_lock() (2013-12-13 09:05:13 -0800) ---------------------------------------------------------------- Paul E. McKenney (7): Documentation/memory-barriers.txt: Add needed ACCESS_ONCE() calls to memory-barriers.txt Documentation/memory-barriers.txt: Add long atomic examples to memory-barriers.txt Documentation/memory-barriers.txt: Document ACCESS_ONCE() locking: Add an smp_mb__after_unlock_lock() for UNLOCK+LOCK barrier Documentation/memory-barriers.txt: Downgrade UNLOCK+LOCK rcu: Apply smp_mb__after_unlock_lock() to preserve grace periods powerpc: Full barrier for smp_mb__after_unlock_lock() Peter Zijlstra (1): Documentation/memory-barriers.txt: Prohibit speculative writes Documentation/memory-barriers.txt | 733 ++++++++++++++++++++++++++++++------ arch/powerpc/include/asm/spinlock.h | 2 + include/linux/spinlock.h | 10 + kernel/rcu/tree.c | 18 +- kernel/rcu/tree_plugin.h | 13 + 5 files changed, 661 insertions(+), 115 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html