mips/gup: Replace ACCESS_ONCE with READ_ONCE
authorChristian Borntraeger <borntraeger@de.ibm.com>
Fri, 21 Nov 2014 15:21:56 +0000 (16:21 +0100)
committerChristian Borntraeger <borntraeger@de.ibm.com>
Thu, 18 Dec 2014 08:54:39 +0000 (09:54 +0100)
commit4218091cb45f601b889cd032e39fe6878a426e70
tree36f63ef018f6842f91b2118240cc6a144ef52571
parent14cf3d977b80f5e355f8ac7547cf1b9ff9fb3e09
mips/gup: Replace ACCESS_ONCE with READ_ONCE

ACCESS_ONCE does not work reliably on non-scalar types. For
example gcc 4.6 and 4.7 might remove the volatile tag for such
accesses during the SRA (scalar replacement of aggregates) step
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145)

Change the gup code to replace ACCESS_ONCE with READ_ONCE.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
arch/mips/mm/gup.c