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authorChris Zankel <chris@zankel.net>2014-02-24 00:34:36 -0800
committerChris Zankel <chris@zankel.net>2014-02-24 00:34:36 -0800
commitb3fdfc1b4b641d372e35ced98814289bc60bc5d1 (patch)
tree5f11d5ba885031dde45690745646519fb887f447 /include/linux/kernel.h
parentc0e50d41126e4786d9cf1105bdf783e55c99f915 (diff)
parentf63b6d7555cd4064554b39da4d44c4cbbc9d6a4a (diff)
Merge tag 'xtensa-for-next-20140221-1' into for_next
Xtensa fixes for 3.14: - allow booting xtfpga on boards with new uBoot and >128MBytes memory; - drop nonexistent GPIO32 support from fsf variant; - don't select USE_GENERIC_SMP_HELPERS; - enable common clock framework support, set up ethoc clock on xtfpga; - wire up sched_setattr and sched_getattr syscalls. Signed-off-by: Chris Zankel <chris@zankel.net>
Diffstat (limited to 'include/linux/kernel.h')
-rw-r--r--include/linux/kernel.h41
1 files changed, 41 insertions, 0 deletions
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index ecb87544cc5d..196d1ea86df0 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -29,6 +29,19 @@
#define ULLONG_MAX (~0ULL)
#define SIZE_MAX (~(size_t)0)
+#define U8_MAX ((u8)~0U)
+#define S8_MAX ((s8)(U8_MAX>>1))
+#define S8_MIN ((s8)(-S8_MAX - 1))
+#define U16_MAX ((u16)~0U)
+#define S16_MAX ((s16)(U16_MAX>>1))
+#define S16_MIN ((s16)(-S16_MAX - 1))
+#define U32_MAX ((u32)~0U)
+#define S32_MAX ((s32)(U32_MAX>>1))
+#define S32_MIN ((s32)(-S32_MAX - 1))
+#define U64_MAX ((u64)~0ULL)
+#define S64_MAX ((s64)(U64_MAX>>1))
+#define S64_MIN ((s64)(-S64_MAX - 1))
+
#define STACK_MAGIC 0xdeadbeef
#define REPEAT_BYTE(x) ((~0ul / 0xff) * (x))
@@ -193,6 +206,25 @@ extern int _cond_resched(void);
(__x < 0) ? -__x : __x; \
})
+/**
+ * reciprocal_scale - "scale" a value into range [0, ep_ro)
+ * @val: value
+ * @ep_ro: right open interval endpoint
+ *
+ * Perform a "reciprocal multiplication" in order to "scale" a value into
+ * range [0, ep_ro), where the upper interval endpoint is right-open.
+ * This is useful, e.g. for accessing a index of an array containing
+ * ep_ro elements, for example. Think of it as sort of modulus, only that
+ * the result isn't that of modulo. ;) Note that if initial input is a
+ * small value, then result will return 0.
+ *
+ * Return: a result based on val in interval [0, ep_ro).
+ */
+static inline u32 reciprocal_scale(u32 val, u32 ep_ro)
+{
+ return (u32)(((u64) val * ep_ro) >> 32);
+}
+
#if defined(CONFIG_MMU) && \
(defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_DEBUG_ATOMIC_SLEEP))
void might_fault(void);
@@ -394,6 +426,15 @@ extern int panic_on_oops;
extern int panic_on_unrecovered_nmi;
extern int panic_on_io_nmi;
extern int sysctl_panic_on_stackoverflow;
+/*
+ * Only to be used by arch init code. If the user over-wrote the default
+ * CONFIG_PANIC_TIMEOUT, honor it.
+ */
+static inline void set_arch_panic_timeout(int timeout, int arch_default_timeout)
+{
+ if (panic_timeout == arch_default_timeout)
+ panic_timeout = timeout;
+}
extern const char *print_tainted(void);
enum lockdep_ok {
LOCKDEP_STILL_OK,