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authorKent Overstreet <kent.overstreet@gmail.com>2018-05-17 03:14:09 -0400
committerKent Overstreet <kent.overstreet@gmail.com>2018-05-17 07:24:39 -0400
commit62e4df2a38081f62fd1bd657459b7ffb2d4f522c (patch)
tree9b4ed5d3c597e19894ca77299b53057efe071c50 /include/linux/jiffies.h
parent426e88e41cdcecd007a689daf4fe432bb61303ec (diff)
drop dead code
Diffstat (limited to 'include/linux/jiffies.h')
-rw-r--r--include/linux/jiffies.h403
1 files changed, 15 insertions, 388 deletions
diff --git a/include/linux/jiffies.h b/include/linux/jiffies.h
index e0dadcf0..9b8dd43d 100644
--- a/include/linux/jiffies.h
+++ b/include/linux/jiffies.h
@@ -6,111 +6,6 @@
#include <linux/typecheck.h>
#include <linux/types.h>
-#define HZ 100
-
-#define MSEC_PER_SEC 1000L
-#define USEC_PER_MSEC 1000L
-#define NSEC_PER_USEC 1000L
-#define NSEC_PER_MSEC 1000000L
-#define USEC_PER_SEC 1000000L
-#define NSEC_PER_SEC 1000000000L
-#define FSEC_PER_SEC 1000000000000000LL
-
-/*
- * The following defines establish the engineering parameters of the PLL
- * model. The HZ variable establishes the timer interrupt frequency, 100 Hz
- * for the SunOS kernel, 256 Hz for the Ultrix kernel and 1024 Hz for the
- * OSF/1 kernel. The SHIFT_HZ define expresses the same value as the
- * nearest power of two in order to avoid hardware multiply operations.
- */
-#if HZ >= 12 && HZ < 24
-# define SHIFT_HZ 4
-#elif HZ >= 24 && HZ < 48
-# define SHIFT_HZ 5
-#elif HZ >= 48 && HZ < 96
-# define SHIFT_HZ 6
-#elif HZ >= 96 && HZ < 192
-# define SHIFT_HZ 7
-#elif HZ >= 192 && HZ < 384
-# define SHIFT_HZ 8
-#elif HZ >= 384 && HZ < 768
-# define SHIFT_HZ 9
-#elif HZ >= 768 && HZ < 1536
-# define SHIFT_HZ 10
-#elif HZ >= 1536 && HZ < 3072
-# define SHIFT_HZ 11
-#elif HZ >= 3072 && HZ < 6144
-# define SHIFT_HZ 12
-#elif HZ >= 6144 && HZ < 12288
-# define SHIFT_HZ 13
-#else
-# error Invalid value of HZ.
-#endif
-
-/* Suppose we want to divide two numbers NOM and DEN: NOM/DEN, then we can
- * improve accuracy by shifting LSH bits, hence calculating:
- * (NOM << LSH) / DEN
- * This however means trouble for large NOM, because (NOM << LSH) may no
- * longer fit in 32 bits. The following way of calculating this gives us
- * some slack, under the following conditions:
- * - (NOM / DEN) fits in (32 - LSH) bits.
- * - (NOM % DEN) fits in (32 - LSH) bits.
- */
-#define SH_DIV(NOM,DEN,LSH) ( (((NOM) / (DEN)) << (LSH)) \
- + ((((NOM) % (DEN)) << (LSH)) + (DEN) / 2) / (DEN))
-
-/* LATCH is used in the interval timer and ftape setup. */
-#define LATCH ((CLOCK_TICK_RATE + HZ/2) / HZ) /* For divider */
-
-extern int register_refined_jiffies(long clock_tick_rate);
-
-/* TICK_NSEC is the time between ticks in nsec assuming SHIFTED_HZ */
-#define TICK_NSEC ((NSEC_PER_SEC+HZ/2)/HZ)
-
-/* TICK_USEC is the time between ticks in usec assuming fake USER_HZ */
-#define TICK_USEC ((1000000UL + USER_HZ/2) / USER_HZ)
-
-static inline u64 sched_clock(void)
-{
- struct timespec ts;
-
- clock_gettime(CLOCK_MONOTONIC, &ts);
-
- return ((s64) ts.tv_sec * NSEC_PER_SEC) + ts.tv_nsec;
-}
-
-static inline u64 local_clock(void)
-{
- return sched_clock();
-}
-
-extern unsigned long clock_t_to_jiffies(unsigned long x);
-extern u64 jiffies_64_to_clock_t(u64 x);
-extern u64 nsec_to_clock_t(u64 x);
-extern u64 nsecs_to_jiffies64(u64 n);
-extern unsigned long nsecs_to_jiffies(u64 n);
-
-static inline u64 get_jiffies_64(void)
-{
- return nsecs_to_jiffies64(sched_clock());
-}
-
-#define jiffies_64 get_jiffies_64()
-#define jiffies ((unsigned long) get_jiffies_64())
-
-/*
- * These inlines deal with timer wrapping correctly. You are
- * strongly encouraged to use them
- * 1. Because people otherwise forget
- * 2. Because if the timer wrap changes in future you won't have to
- * alter your driver code.
- *
- * time_after(a,b) returns true if the time a is after time b.
- *
- * Do this with "<0" and ">=0" to only test the sign of the result. A
- * good compiler would generate better code (and a really good compiler
- * wouldn't care). Gcc is currently neither.
- */
#define time_after(a,b) \
(typecheck(unsigned long, a) && \
typecheck(unsigned long, b) && \
@@ -123,23 +18,14 @@ static inline u64 get_jiffies_64(void)
((long)((a) - (b)) >= 0))
#define time_before_eq(a,b) time_after_eq(b,a)
-/*
- * Calculate whether a is in the range of [b, c].
- */
#define time_in_range(a,b,c) \
(time_after_eq(a,b) && \
time_before_eq(a,c))
-/*
- * Calculate whether a is in the range of [b, c).
- */
#define time_in_range_open(a,b,c) \
(time_after_eq(a,b) && \
time_before(a,c))
-/* Same as above, but does so with platform independent 64bit types.
- * These must be used when utilizing jiffies_64 (i.e. return value of
- * get_jiffies_64() */
#define time_after64(a,b) \
(typecheck(__u64, a) && \
typecheck(__u64, b) && \
@@ -156,301 +42,42 @@ static inline u64 get_jiffies_64(void)
(time_after_eq64(a, b) && \
time_before_eq64(a, c))
-/*
- * These four macros compare jiffies and 'a' for convenience.
- */
-
-/* time_is_before_jiffies(a) return true if a is before jiffies */
-#define time_is_before_jiffies(a) time_after(jiffies, a)
-
-/* time_is_after_jiffies(a) return true if a is after jiffies */
-#define time_is_after_jiffies(a) time_before(jiffies, a)
-
-/* time_is_before_eq_jiffies(a) return true if a is before or equal to jiffies*/
-#define time_is_before_eq_jiffies(a) time_after_eq(jiffies, a)
-
-/* time_is_after_eq_jiffies(a) return true if a is after or equal to jiffies*/
-#define time_is_after_eq_jiffies(a) time_before_eq(jiffies, a)
-
-/*
- * Have the 32 bit jiffies value wrap 5 minutes after boot
- * so jiffies wrap bugs show up earlier.
- */
-#define INITIAL_JIFFIES ((unsigned long)(unsigned int) (-300*HZ))
-
-/*
- * Change timeval to jiffies, trying to avoid the
- * most obvious overflows..
- *
- * And some not so obvious.
- *
- * Note that we don't want to return LONG_MAX, because
- * for various timeout reasons we often end up having
- * to wait "jiffies+1" in order to guarantee that we wait
- * at _least_ "jiffies" - so "jiffies+1" had better still
- * be positive.
- */
-#define MAX_JIFFY_OFFSET ((LONG_MAX >> 1)-1)
-
-extern unsigned long preset_lpj;
-
-/*
- * We want to do realistic conversions of time so we need to use the same
- * values the update wall clock code uses as the jiffies size. This value
- * is: TICK_NSEC (which is defined in timex.h). This
- * is a constant and is in nanoseconds. We will use scaled math
- * with a set of scales defined here as SEC_JIFFIE_SC, USEC_JIFFIE_SC and
- * NSEC_JIFFIE_SC. Note that these defines contain nothing but
- * constants and so are computed at compile time. SHIFT_HZ (computed in
- * timex.h) adjusts the scaling for different HZ values.
-
- * Scaled math??? What is that?
- *
- * Scaled math is a way to do integer math on values that would,
- * otherwise, either overflow, underflow, or cause undesired div
- * instructions to appear in the execution path. In short, we "scale"
- * up the operands so they take more bits (more precision, less
- * underflow), do the desired operation and then "scale" the result back
- * by the same amount. If we do the scaling by shifting we avoid the
- * costly mpy and the dastardly div instructions.
-
- * Suppose, for example, we want to convert from seconds to jiffies
- * where jiffies is defined in nanoseconds as NSEC_PER_JIFFIE. The
- * simple math is: jiff = (sec * NSEC_PER_SEC) / NSEC_PER_JIFFIE; We
- * observe that (NSEC_PER_SEC / NSEC_PER_JIFFIE) is a constant which we
- * might calculate at compile time, however, the result will only have
- * about 3-4 bits of precision (less for smaller values of HZ).
- *
- * So, we scale as follows:
- * jiff = (sec) * (NSEC_PER_SEC / NSEC_PER_JIFFIE);
- * jiff = ((sec) * ((NSEC_PER_SEC * SCALE)/ NSEC_PER_JIFFIE)) / SCALE;
- * Then we make SCALE a power of two so:
- * jiff = ((sec) * ((NSEC_PER_SEC << SCALE)/ NSEC_PER_JIFFIE)) >> SCALE;
- * Now we define:
- * #define SEC_CONV = ((NSEC_PER_SEC << SCALE)/ NSEC_PER_JIFFIE))
- * jiff = (sec * SEC_CONV) >> SCALE;
- *
- * Often the math we use will expand beyond 32-bits so we tell C how to
- * do this and pass the 64-bit result of the mpy through the ">> SCALE"
- * which should take the result back to 32-bits. We want this expansion
- * to capture as much precision as possible. At the same time we don't
- * want to overflow so we pick the SCALE to avoid this. In this file,
- * that means using a different scale for each range of HZ values (as
- * defined in timex.h).
- *
- * For those who want to know, gcc will give a 64-bit result from a "*"
- * operator if the result is a long long AND at least one of the
- * operands is cast to long long (usually just prior to the "*" so as
- * not to confuse it into thinking it really has a 64-bit operand,
- * which, buy the way, it can do, but it takes more code and at least 2
- * mpys).
-
- * We also need to be aware that one second in nanoseconds is only a
- * couple of bits away from overflowing a 32-bit word, so we MUST use
- * 64-bits to get the full range time in nanoseconds.
-
- */
-
-/*
- * Here are the scales we will use. One for seconds, nanoseconds and
- * microseconds.
- *
- * Within the limits of cpp we do a rough cut at the SEC_JIFFIE_SC and
- * check if the sign bit is set. If not, we bump the shift count by 1.
- * (Gets an extra bit of precision where we can use it.)
- * We know it is set for HZ = 1024 and HZ = 100 not for 1000.
- * Haven't tested others.
-
- * Limits of cpp (for #if expressions) only long (no long long), but
- * then we only need the most signicant bit.
- */
-
-#define SEC_JIFFIE_SC (31 - SHIFT_HZ)
-#if !((((NSEC_PER_SEC << 2) / TICK_NSEC) << (SEC_JIFFIE_SC - 2)) & 0x80000000)
-#undef SEC_JIFFIE_SC
-#define SEC_JIFFIE_SC (32 - SHIFT_HZ)
-#endif
-#define NSEC_JIFFIE_SC (SEC_JIFFIE_SC + 29)
-#define SEC_CONVERSION ((unsigned long)((((u64)NSEC_PER_SEC << SEC_JIFFIE_SC) +\
- TICK_NSEC -1) / (u64)TICK_NSEC))
-
-#define NSEC_CONVERSION ((unsigned long)((((u64)1 << NSEC_JIFFIE_SC) +\
- TICK_NSEC -1) / (u64)TICK_NSEC))
-/*
- * The maximum jiffie value is (MAX_INT >> 1). Here we translate that
- * into seconds. The 64-bit case will overflow if we are not careful,
- * so use the messy SH_DIV macro to do it. Still all constants.
- */
-#if BITS_PER_LONG < 64
-# define MAX_SEC_IN_JIFFIES \
- (long)((u64)((u64)MAX_JIFFY_OFFSET * TICK_NSEC) / NSEC_PER_SEC)
-#else /* take care of overflow on 64 bits machines */
-# define MAX_SEC_IN_JIFFIES \
- (SH_DIV((MAX_JIFFY_OFFSET >> SEC_JIFFIE_SC) * TICK_NSEC, NSEC_PER_SEC, 1) - 1)
-
-#endif
-
-/*
- * Convert various time units to each other:
- */
-extern unsigned int jiffies_to_msecs(const unsigned long j);
-extern unsigned int jiffies_to_usecs(const unsigned long j);
+#define HZ 1000
static inline u64 jiffies_to_nsecs(const unsigned long j)
{
- return (u64)jiffies_to_usecs(j) * NSEC_PER_USEC;
+ return (u64)j * NSEC_PER_MSEC;
}
-extern unsigned long __msecs_to_jiffies(const unsigned int m);
-#if HZ <= MSEC_PER_SEC && !(MSEC_PER_SEC % HZ)
-/*
- * HZ is equal to or smaller than 1000, and 1000 is a nice round
- * multiple of HZ, divide with the factor between them, but round
- * upwards:
- */
-static inline unsigned long _msecs_to_jiffies(const unsigned int m)
+static inline unsigned jiffies_to_msecs(const unsigned long j)
{
- return (m + (MSEC_PER_SEC / HZ) - 1) / (MSEC_PER_SEC / HZ);
+ return j;
}
-#elif HZ > MSEC_PER_SEC && !(HZ % MSEC_PER_SEC)
-/*
- * HZ is larger than 1000, and HZ is a nice round multiple of 1000 -
- * simply multiply with the factor between them.
- *
- * But first make sure the multiplication result cannot overflow:
- */
-static inline unsigned long _msecs_to_jiffies(const unsigned int m)
-{
- if (m > jiffies_to_msecs(MAX_JIFFY_OFFSET))
- return MAX_JIFFY_OFFSET;
- return m * (HZ / MSEC_PER_SEC);
-}
-#else
-/*
- * Generic case - multiply, round and divide. But first check that if
- * we are doing a net multiplication, that we wouldn't overflow:
- */
-static inline unsigned long _msecs_to_jiffies(const unsigned int m)
-{
- if (HZ > MSEC_PER_SEC && m > jiffies_to_msecs(MAX_JIFFY_OFFSET))
- return MAX_JIFFY_OFFSET;
- return (MSEC_TO_HZ_MUL32 * m + MSEC_TO_HZ_ADJ32) >> MSEC_TO_HZ_SHR32;
-}
-#endif
-/**
- * msecs_to_jiffies: - convert milliseconds to jiffies
- * @m: time in milliseconds
- *
- * conversion is done as follows:
- *
- * - negative values mean 'infinite timeout' (MAX_JIFFY_OFFSET)
- *
- * - 'too large' values [that would result in larger than
- * MAX_JIFFY_OFFSET values] mean 'infinite timeout' too.
- *
- * - all other values are converted to jiffies by either multiplying
- * the input value by a factor or dividing it with a factor and
- * handling any 32-bit overflows.
- * for the details see __msecs_to_jiffies()
- *
- * msecs_to_jiffies() checks for the passed in value being a constant
- * via __builtin_constant_p() allowing gcc to eliminate most of the
- * code, __msecs_to_jiffies() is called if the value passed does not
- * allow constant folding and the actual conversion must be done at
- * runtime.
- * the HZ range specific helpers _msecs_to_jiffies() are called both
- * directly here and from __msecs_to_jiffies() in the case where
- * constant folding is not possible.
- */
-static __always_inline unsigned long msecs_to_jiffies(const unsigned int m)
+static inline unsigned long msecs_to_jiffies(const unsigned int m)
{
- if (__builtin_constant_p(m)) {
- if ((int)m < 0)
- return MAX_JIFFY_OFFSET;
- return _msecs_to_jiffies(m);
- } else {
- return __msecs_to_jiffies(m);
- }
+ return m;
}
-extern unsigned long __usecs_to_jiffies(const unsigned int u);
-#if !(USEC_PER_SEC % HZ)
-static inline unsigned long _usecs_to_jiffies(const unsigned int u)
+static inline unsigned long nsecs_to_jiffies(u64 n)
{
- return (u + (USEC_PER_SEC / HZ) - 1) / (USEC_PER_SEC / HZ);
+ return n / NSEC_PER_MSEC;
}
-#else
-static inline unsigned long _usecs_to_jiffies(const unsigned int u)
-{
- return (USEC_TO_HZ_MUL32 * u + USEC_TO_HZ_ADJ32)
- >> USEC_TO_HZ_SHR32;
-}
-#endif
-/**
- * usecs_to_jiffies: - convert microseconds to jiffies
- * @u: time in microseconds
- *
- * conversion is done as follows:
- *
- * - 'too large' values [that would result in larger than
- * MAX_JIFFY_OFFSET values] mean 'infinite timeout' too.
- *
- * - all other values are converted to jiffies by either multiplying
- * the input value by a factor or dividing it with a factor and
- * handling any 32-bit overflows as for msecs_to_jiffies.
- *
- * usecs_to_jiffies() checks for the passed in value being a constant
- * via __builtin_constant_p() allowing gcc to eliminate most of the
- * code, __usecs_to_jiffies() is called if the value passed does not
- * allow constant folding and the actual conversion must be done at
- * runtime.
- * the HZ range specific helpers _usecs_to_jiffies() are called both
- * directly here and from __msecs_to_jiffies() in the case where
- * constant folding is not possible.
- */
-static __always_inline unsigned long usecs_to_jiffies(const unsigned int u)
-{
- if (__builtin_constant_p(u)) {
- if (u > jiffies_to_usecs(MAX_JIFFY_OFFSET))
- return MAX_JIFFY_OFFSET;
- return _usecs_to_jiffies(u);
- } else {
- return __usecs_to_jiffies(u);
- }
-}
-
-extern unsigned long timespec64_to_jiffies(const struct timespec64 *value);
-
-extern void jiffies_to_timespec64(const unsigned long,
- struct timespec64 *value);
-static inline unsigned long timespec_to_jiffies(const struct timespec *value)
+static inline u64 sched_clock(void)
{
- struct timespec64 ts = timespec_to_timespec64(*value);
-
- return timespec64_to_jiffies(&ts);
-}
+ struct timespec ts;
-static inline void jiffies_to_timespec(const unsigned long j,
- struct timespec *value)
-{
- struct timespec64 ts;
+ clock_gettime(CLOCK_MONOTONIC, &ts);
- jiffies_to_timespec64(j, &ts);
- *value = timespec64_to_timespec(ts);
+ return ((s64) ts.tv_sec * NSEC_PER_SEC) + ts.tv_nsec;
}
-extern unsigned long timeval_to_jiffies(const struct timeval *value);
-extern void jiffies_to_timeval(const unsigned long j,
- struct timeval *value);
-
-extern clock_t jiffies_to_clock_t(unsigned long x);
-static inline clock_t jiffies_delta_to_clock_t(long delta)
+static inline u64 local_clock(void)
{
- return jiffies_to_clock_t(max(0L, delta));
+ return sched_clock();
}
-#define TIMESTAMP_SIZE 30
+#define jiffies nsecs_to_jiffies(sched_clock())
#endif