diff options
author | Will Deacon <will.deacon@arm.com> | 2014-04-30 16:23:06 +0100 |
---|---|---|
committer | Mark Brown <broonie@linaro.org> | 2014-08-11 21:41:37 +0100 |
commit | 90bc330383ed6799f1f0164509f836c9b82ad8b1 (patch) | |
tree | 1b473f1f96c1f65c67c9f204af8dc196aecdfd7c /arch/arm64/include/asm/cacheflush.h | |
parent | f526505e136a6ed9d3b8457efe9880eb6569dfda (diff) |
arm64: xchg: prevent warning if return value is unused
Some users of xchg() don't bother using the return value, which results
in a compiler warning like the following (from kgdb):
In file included from linux/arch/arm64/include/asm/atomic.h:27:0,
from include/linux/atomic.h:4,
from include/linux/spinlock.h:402,
from include/linux/seqlock.h:35,
from include/linux/time.h:5,
from include/uapi/linux/timex.h:56,
from include/linux/timex.h:56,
from include/linux/sched.h:19,
from include/linux/pid_namespace.h:4,
from kernel/debug/debug_core.c:30:
kernel/debug/debug_core.c: In function ‘kgdb_cpu_enter’:
linux/arch/arm64/include/asm/cmpxchg.h:75:3: warning: value computed is not used [-Wunused-value]
((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
^
linux/arch/arm64/include/asm/atomic.h:132:30: note: in expansion of macro ‘xchg’
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
kernel/debug/debug_core.c:504:4: note: in expansion of macro ‘atomic_xchg’
atomic_xchg(&kgdb_active, cpu);
^
This patch makes use of the same trick as we do for cmpxchg, by assigning
the return value to a dummy variable in the xchg() macro itself.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit e1dfda9ced9bea1413a736f0d578f8218a7788ec)
Signed-off-by: Mark Brown <broonie@linaro.org>
Diffstat (limited to 'arch/arm64/include/asm/cacheflush.h')
0 files changed, 0 insertions, 0 deletions