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authorJames Morris <jmorris@namei.org>2011-03-08 10:55:06 +1100
committerJames Morris <jmorris@namei.org>2011-03-08 10:55:06 +1100
commit1cc26bada9f6807814806db2f0d78792eecdac71 (patch)
tree5509b5139db04af6c13db0a580c84116a4a54039 /include/linux/kernel.h
parentTOMOYO: Fix memory leak upon file open. (diff)
parentMerge branch 'omap-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6 (diff)
downloadlinux-dev-1cc26bada9f6807814806db2f0d78792eecdac71.tar.xz
linux-dev-1cc26bada9f6807814806db2f0d78792eecdac71.zip
Merge branch 'master'; commit 'v2.6.38-rc7' into next
Diffstat (limited to 'include/linux/kernel.h')
-rw-r--r--include/linux/kernel.h60
1 files changed, 51 insertions, 9 deletions
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index d0fbc043de60..2fe6e84894a4 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -143,9 +143,22 @@ extern int _cond_resched(void);
#define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
-#define abs(x) ({ \
- long __x = (x); \
- (__x < 0) ? -__x : __x; \
+/*
+ * abs() handles unsigned and signed longs, ints, shorts and chars. For all
+ * input types abs() returns a signed long.
+ * abs() should not be used for 64-bit types (s64, u64, long long) - use abs64()
+ * for those.
+ */
+#define abs(x) ({ \
+ long ret; \
+ if (sizeof(x) == sizeof(long)) { \
+ long __x = (x); \
+ ret = (__x < 0) ? -__x : __x; \
+ } else { \
+ int __x = (x); \
+ ret = (__x < 0) ? -__x : __x; \
+ } \
+ ret; \
})
#define abs64(x) ({ \
@@ -230,6 +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,
@@ -560,12 +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))
@@ -577,6 +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.
+ * @condition: 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__)
@@ -587,6 +622,13 @@ struct sysinfo {
#define NUMA_BUILD 0
#endif
+/* This helps us avoid #ifdef CONFIG_COMPACTION */
+#ifdef CONFIG_COMPACTION
+#define COMPACTION_BUILD 1
+#else
+#define COMPACTION_BUILD 0
+#endif
+
/* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
#ifdef CONFIG_FTRACE_MCOUNT_RECORD
# define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD