From 230fa253df6352af12ad0a16128760b5cb3f92df Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Tue, 25 Nov 2014 10:01:16 +0100 Subject: [PATCH] kernel: Provide READ_ONCE and ASSIGN_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) Let's provide READ_ONCE/ASSIGN_ONCE that will do all accesses via scalar types as suggested by Linus Torvalds. Accesses larger than the machines word size cannot be guaranteed to be atomic. These macros will use memcpy and emit a build warning. Signed-off-by: Christian Borntraeger --- Reading git-format-patch failed