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[PATCH] Uninline jiffies.h functions
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There are loads of fat functions hidden in jiffies.h.  Uninline them.  No code
changes.

[[email protected]: export fix]
Signed-off-by: Ingo Molnar <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: john stultz <[email protected]>
Cc: Roman Zippel <[email protected]>
Cc: Jeremy Fitzhardinge <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
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Ingo Molnar authored and Linus Torvalds committed Feb 16, 2007
1 parent f4304ab commit 8b9365d
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Showing 2 changed files with 230 additions and 201 deletions.
218 changes: 17 additions & 201 deletions include/linux/jiffies.h
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Original file line number Diff line number Diff line change
Expand Up @@ -259,207 +259,23 @@ static inline u64 get_jiffies_64(void)
#endif

/*
* Convert jiffies to milliseconds and back.
*
* Avoid unnecessary multiplications/divisions in the
* two most common HZ cases:
*/
static inline unsigned int jiffies_to_msecs(const unsigned long j)
{
#if HZ <= MSEC_PER_SEC && !(MSEC_PER_SEC % HZ)
return (MSEC_PER_SEC / HZ) * j;
#elif HZ > MSEC_PER_SEC && !(HZ % MSEC_PER_SEC)
return (j + (HZ / MSEC_PER_SEC) - 1)/(HZ / MSEC_PER_SEC);
#else
return (j * MSEC_PER_SEC) / HZ;
#endif
}

static inline unsigned int jiffies_to_usecs(const unsigned long j)
{
#if HZ <= USEC_PER_SEC && !(USEC_PER_SEC % HZ)
return (USEC_PER_SEC / HZ) * j;
#elif HZ > USEC_PER_SEC && !(HZ % USEC_PER_SEC)
return (j + (HZ / USEC_PER_SEC) - 1)/(HZ / USEC_PER_SEC);
#else
return (j * USEC_PER_SEC) / HZ;
#endif
}

static inline unsigned long msecs_to_jiffies(const unsigned int m)
{
if (m > jiffies_to_msecs(MAX_JIFFY_OFFSET))
return MAX_JIFFY_OFFSET;
#if HZ <= MSEC_PER_SEC && !(MSEC_PER_SEC % HZ)
return (m + (MSEC_PER_SEC / HZ) - 1) / (MSEC_PER_SEC / HZ);
#elif HZ > MSEC_PER_SEC && !(HZ % MSEC_PER_SEC)
return m * (HZ / MSEC_PER_SEC);
#else
return (m * HZ + MSEC_PER_SEC - 1) / MSEC_PER_SEC;
#endif
}

static inline unsigned long usecs_to_jiffies(const unsigned int u)
{
if (u > jiffies_to_usecs(MAX_JIFFY_OFFSET))
return MAX_JIFFY_OFFSET;
#if HZ <= USEC_PER_SEC && !(USEC_PER_SEC % HZ)
return (u + (USEC_PER_SEC / HZ) - 1) / (USEC_PER_SEC / HZ);
#elif HZ > USEC_PER_SEC && !(HZ % USEC_PER_SEC)
return u * (HZ / USEC_PER_SEC);
#else
return (u * HZ + USEC_PER_SEC - 1) / USEC_PER_SEC;
#endif
}

/*
* The TICK_NSEC - 1 rounds up the value to the next resolution. Note
* that a remainder subtract here would not do the right thing as the
* resolution values don't fall on second boundries. I.e. the line:
* nsec -= nsec % TICK_NSEC; is NOT a correct resolution rounding.
*
* Rather, we just shift the bits off the right.
*
* The >> (NSEC_JIFFIE_SC - SEC_JIFFIE_SC) converts the scaled nsec
* value to a scaled second value.
*/
static __inline__ unsigned long
timespec_to_jiffies(const struct timespec *value)
{
unsigned long sec = value->tv_sec;
long nsec = value->tv_nsec + TICK_NSEC - 1;

if (sec >= MAX_SEC_IN_JIFFIES){
sec = MAX_SEC_IN_JIFFIES;
nsec = 0;
}
return (((u64)sec * SEC_CONVERSION) +
(((u64)nsec * NSEC_CONVERSION) >>
(NSEC_JIFFIE_SC - SEC_JIFFIE_SC))) >> SEC_JIFFIE_SC;

}

static __inline__ void
jiffies_to_timespec(const unsigned long jiffies, struct timespec *value)
{
/*
* Convert jiffies to nanoseconds and separate with
* one divide.
*/
u64 nsec = (u64)jiffies * TICK_NSEC;
value->tv_sec = div_long_long_rem(nsec, NSEC_PER_SEC, &value->tv_nsec);
}

/* Same for "timeval"
*
* Well, almost. The problem here is that the real system resolution is
* in nanoseconds and the value being converted is in micro seconds.
* Also for some machines (those that use HZ = 1024, in-particular),
* there is a LARGE error in the tick size in microseconds.
* The solution we use is to do the rounding AFTER we convert the
* microsecond part. Thus the USEC_ROUND, the bits to be shifted off.
* Instruction wise, this should cost only an additional add with carry
* instruction above the way it was done above.
*/
static __inline__ unsigned long
timeval_to_jiffies(const struct timeval *value)
{
unsigned long sec = value->tv_sec;
long usec = value->tv_usec;

if (sec >= MAX_SEC_IN_JIFFIES){
sec = MAX_SEC_IN_JIFFIES;
usec = 0;
}
return (((u64)sec * SEC_CONVERSION) +
(((u64)usec * USEC_CONVERSION + USEC_ROUND) >>
(USEC_JIFFIE_SC - SEC_JIFFIE_SC))) >> SEC_JIFFIE_SC;
}

static __inline__ void
jiffies_to_timeval(const unsigned long jiffies, struct timeval *value)
{
/*
* Convert jiffies to nanoseconds and separate with
* one divide.
*/
u64 nsec = (u64)jiffies * TICK_NSEC;
long tv_usec;

value->tv_sec = div_long_long_rem(nsec, NSEC_PER_SEC, &tv_usec);
tv_usec /= NSEC_PER_USEC;
value->tv_usec = tv_usec;
}

/*
* Convert jiffies/jiffies_64 to clock_t and back.
* Convert various time units to each other:
*/
static inline clock_t jiffies_to_clock_t(long x)
{
#if (TICK_NSEC % (NSEC_PER_SEC / USER_HZ)) == 0
return x / (HZ / USER_HZ);
#else
u64 tmp = (u64)x * TICK_NSEC;
do_div(tmp, (NSEC_PER_SEC / USER_HZ));
return (long)tmp;
#endif
}

static inline unsigned long clock_t_to_jiffies(unsigned long x)
{
#if (HZ % USER_HZ)==0
if (x >= ~0UL / (HZ / USER_HZ))
return ~0UL;
return x * (HZ / USER_HZ);
#else
u64 jif;

/* Don't worry about loss of precision here .. */
if (x >= ~0UL / HZ * USER_HZ)
return ~0UL;

/* .. but do try to contain it here */
jif = x * (u64) HZ;
do_div(jif, USER_HZ);
return jif;
#endif
}

static inline u64 jiffies_64_to_clock_t(u64 x)
{
#if (TICK_NSEC % (NSEC_PER_SEC / USER_HZ)) == 0
do_div(x, HZ / USER_HZ);
#else
/*
* There are better ways that don't overflow early,
* but even this doesn't overflow in hundreds of years
* in 64 bits, so..
*/
x *= TICK_NSEC;
do_div(x, (NSEC_PER_SEC / USER_HZ));
#endif
return x;
}

static inline u64 nsec_to_clock_t(u64 x)
{
#if (NSEC_PER_SEC % USER_HZ) == 0
do_div(x, (NSEC_PER_SEC / USER_HZ));
#elif (USER_HZ % 512) == 0
x *= USER_HZ/512;
do_div(x, (NSEC_PER_SEC / 512));
#else
/*
* max relative error 5.7e-8 (1.8s per year) for USER_HZ <= 1024,
* overflow after 64.99 years.
* exact for HZ=60, 72, 90, 120, 144, 180, 300, 600, 900, ...
*/
x *= 9;
do_div(x, (unsigned long)((9ull * NSEC_PER_SEC + (USER_HZ/2))
/ USER_HZ));
#endif
return x;
}
extern unsigned int jiffies_to_msecs(const unsigned long j);
extern unsigned int jiffies_to_usecs(const unsigned long j);
extern unsigned long msecs_to_jiffies(const unsigned int m);
extern unsigned long usecs_to_jiffies(const unsigned int u);
extern unsigned long timespec_to_jiffies(const struct timespec *value);
extern void jiffies_to_timespec(const unsigned long jiffies,
struct timespec *value);
extern unsigned long timeval_to_jiffies(const struct timeval *value);
extern void jiffies_to_timeval(const unsigned long jiffies,
struct timeval *value);
extern clock_t jiffies_to_clock_t(long x);
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);

#define TIMESTAMP_SIZE 30

#endif
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