diff options
| author | Jan Blunck <jblunck@suse.de> | 2006-09-25 23:30:53 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-09-26 08:48:44 -0700 |
| commit | 632bbfeee4f042c05bc65150b4433a297d3fe387 (patch) | |
| tree | ce67b5fa4bec38610fc0ecb9b20be6aa69763bb3 /include/linux/percpu.h | |
| parent | 0a2966b48fb784e437520e400ddc94874ddbd4e8 (diff) | |
[PATCH] trigger a syntax error if percpu macros are incorrectly used
get_cpu_var()/per_cpu()/__get_cpu_var() arguments must be simple
identifiers. Otherwise the arch dependent implementations might break.
This patch enforces the correct usage of the macros by producing a syntax
error if the variable is not a simple identifier.
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'include/linux/percpu.h')
| -rw-r--r-- | include/linux/percpu.h | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/include/linux/percpu.h b/include/linux/percpu.h index cb9039a21f2a..f926490a7d8b 100644 --- a/include/linux/percpu.h +++ b/include/linux/percpu.h @@ -11,8 +11,14 @@ #define PERCPU_ENOUGH_ROOM 32768 #endif -/* Must be an lvalue. */ -#define get_cpu_var(var) (*({ preempt_disable(); &__get_cpu_var(var); })) +/* + * Must be an lvalue. Since @var must be a simple identifier, + * we force a syntax error here if it isn't. + */ +#define get_cpu_var(var) (*({ \ + extern int simple_indentifier_##var(void); \ + preempt_disable(); \ + &__get_cpu_var(var); })) #define put_cpu_var(var) preempt_enable() #ifdef CONFIG_SMP |