On 01/14/2016 02:24 PM, Paul E. McKenney wrote:
Actually, the Linux kernel doesn't have an acquire barrier, just an
smp_load_acquire(). Or did someone sneak one in while I wasn't looking?
That was an exactly starting point for this discussion. This patch just
pulls out from MIPS files smp_load_acquire() and smp_store_release().
However, I put into LMO half year ago the patch
http://patchwork.linux-mips.org/patch/10506/ which replaces a generic
smp_mb with MIPS specific smp_release/acquire in that functions. This
patch also fixes use of SYNCs barriers in spin_locks/atomics/bitops for
Imagination MIPS CPUs too - it is just absent now for any Imagination
MIPS CPUs!
Michael later pointed me that it can be returned back with his series of
patches but discussion was already here.
- Leonid.