diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-25 17:52:22 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-25 17:52:22 -0700 |
| commit | 94df491c4a01b39d81279a68386158eb02656712 (patch) | |
| tree | ba431d9d74f11a7117883df54908ea39e4ef7c5c /include/asm-generic | |
| parent | 26ff6801f751cd47e44c2e9507ec08b447f2d2b9 (diff) | |
| parent | 29096202176ceaa5016a17ea2dd1aea19a4e90e2 (diff) | |
Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
futex: Fix WARN_ON() test for UP
WARN_ON_SMP(): Allow use in if() statements on UP
x86, dumpstack: Use %pB format specifier for stack trace
vsprintf: Introduce %pB format specifier
lockdep: Remove unused 'factor' variable from lockdep_stats_show()
Diffstat (limited to 'include/asm-generic')
| -rw-r--r-- | include/asm-generic/bug.h | 28 |
1 files changed, 27 insertions, 1 deletions
diff --git a/include/asm-generic/bug.h b/include/asm-generic/bug.h index c2c9ba032d46..f2d2faf4d9ae 100644 --- a/include/asm-generic/bug.h +++ b/include/asm-generic/bug.h @@ -165,10 +165,36 @@ extern void warn_slowpath_null(const char *file, const int line); #define WARN_ON_RATELIMIT(condition, state) \ WARN_ON((condition) && __ratelimit(state)) +/* + * WARN_ON_SMP() is for cases that the warning is either + * meaningless for !SMP or may even cause failures. + * This is usually used for cases that we have + * WARN_ON(!spin_is_locked(&lock)) checks, as spin_is_locked() + * returns 0 for uniprocessor settings. + * It can also be used with values that are only defined + * on SMP: + * + * struct foo { + * [...] + * #ifdef CONFIG_SMP + * int bar; + * #endif + * }; + * + * void func(struct foo *zoot) + * { + * WARN_ON_SMP(!zoot->bar); + * + * For CONFIG_SMP, WARN_ON_SMP() should act the same as WARN_ON(), + * and should be a nop and return false for uniprocessor. + * + * if (WARN_ON_SMP(x)) returns true only when CONFIG_SMP is set + * and x is true. + */ #ifdef CONFIG_SMP # define WARN_ON_SMP(x) WARN_ON(x) #else -# define WARN_ON_SMP(x) do { } while (0) +# define WARN_ON_SMP(x) ({0;}) #endif #endif |