Commit 91241681 authored by Michal Hocko's avatar Michal Hocko Committed by Linus Torvalds
Browse files

include/linux/mmdebug.h: make VM_WARN* non-rvals 



At present the construct

	if (VM_WARN(...))

will compile OK with CONFIG_DEBUG_VM=y and will fail with
CONFIG_DEBUG_VM=n.  The reason is that VM_{WARN,BUG}* have always been
special wrt.  {WARN/BUG}* and never generate any code when DEBUG_VM is
disabled.  So we cannot really use it in conditionals.

We considered changing things so that this construct works in both cases
but that might cause unwanted code generation with CONFIG_DEBUG_VM=n.
It is safer and simpler to make the build fail in both cases.

[akpm@linux-foundation.org: changelog]
Signed-off-by: default avatarMichal Hocko <mhocko@suse.com>
Reviewed-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 2c7452a0

include/linux/mmdebug.h

+4 −4
Original line number Diff line number Diff line
@@ -37,10 +37,10 @@ void dump_mm(const struct mm_struct *mm); 
			BUG();						\

		}							\

	} while (0)

#define VM_WARN_ON(cond) WARN_ON(cond)

#define VM_WARN_ON_ONCE(cond) WARN_ON_ONCE(cond)

#define VM_WARN_ONCE(cond, format...) WARN_ONCE(cond, format)

#define VM_WARN(cond, format...) WARN(cond, format)

#define VM_WARN_ON(cond) (void)WARN_ON(cond)

#define VM_WARN_ON_ONCE(cond) (void)WARN_ON_ONCE(cond)

#define VM_WARN_ONCE(cond, format...) (void)WARN_ONCE(cond, format)

#define VM_WARN(cond, format...) (void)WARN(cond, format)

#else

#define VM_BUG_ON(cond) BUILD_BUG_ON_INVALID(cond)

#define VM_BUG_ON_PAGE(cond, page) VM_BUG_ON(cond)