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authorChris Wilson <chris@chris-wilson.co.uk>2011-01-23 17:22:16 +0000
committerChris Wilson <chris@chris-wilson.co.uk>2011-01-24 18:27:32 +0000
commit8a327f23e23fa509e6e3c2263ae1cc0a67dec387 (patch)
tree119abf09e1ec9babaf78e6889187f9d54864b118 /include/linux/kernel.h
parent5a9a8d1a99c617df82339456fbdd30d6ed3a856b (diff)
parentd315777b32a4696feb86f2a0c9e9f39c94683649 (diff)
Merge remote branch 'linus/master' into drm-intel-fixes
Merge with Linus to resolve conflicting fixes for the reusing the stale HEAD value during intel_ring_wait(). Conflicts: drivers/gpu/drm/i915/intel_ringbuffer.c
Diffstat (limited to 'include/linux/kernel.h')
-rw-r--r--include/linux/kernel.h34
1 files changed, 28 insertions, 6 deletions
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 5a9d9059520b..e2f4d6af2125 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -243,6 +243,8 @@ extern int test_taint(unsigned flag);
extern unsigned long get_taint(void);
extern int root_mountflags;
+extern bool early_boot_irqs_disabled;
+
/* Values used for system_state */
extern enum system_states {
SYSTEM_BOOTING,
@@ -573,12 +575,6 @@ struct sysinfo {
char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
};
-/* Force a compilation error if condition is true */
-#define BUILD_BUG_ON(condition) ((void)BUILD_BUG_ON_ZERO(condition))
-
-/* Force a compilation error if condition is constant and true */
-#define MAYBE_BUILD_BUG_ON(cond) ((void)sizeof(char[1 - 2 * !!(cond)]))
-
/* Force a compilation error if a constant expression is not a power of 2 */
#define BUILD_BUG_ON_NOT_POWER_OF_2(n) \
BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0))
@@ -590,6 +586,32 @@ struct sysinfo {
#define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
#define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
+/**
+ * BUILD_BUG_ON - break compile if a condition is true.
+ * @cond: the condition which the compiler should know is false.
+ *
+ * If you have some code which relies on certain constants being equal, or
+ * other compile-time-evaluated condition, you should use BUILD_BUG_ON to
+ * detect if someone changes it.
+ *
+ * The implementation uses gcc's reluctance to create a negative array, but
+ * gcc (as of 4.4) only emits that error for obvious cases (eg. not arguments
+ * to inline functions). So as a fallback we use the optimizer; if it can't
+ * prove the condition is false, it will cause a link error on the undefined
+ * "__build_bug_on_failed". This error message can be harder to track down
+ * though, hence the two different methods.
+ */
+#ifndef __OPTIMIZE__
+#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
+#else
+extern int __build_bug_on_failed;
+#define BUILD_BUG_ON(condition) \
+ do { \
+ ((void)sizeof(char[1 - 2*!!(condition)])); \
+ if (condition) __build_bug_on_failed = 1; \
+ } while(0)
+#endif
+
/* Trap pasters of __FUNCTION__ at compile-time */
#define __FUNCTION__ (__func__)