High-res-timers part 1 (core) take 23

diff -urP -I \$Id:.*Exp \$ -X /usr/src/patch.exclude linux-2.5.54-bk1-posix/include/linux/hrtime.h linux/include/linux/hrtime.h
@@ -0,0 +1,155 @@
+#ifndef _HRTIME_H
+#define _HRTIME_H
+
+/*
+ * This file is the glue to bring in the platform stuff.
+ * We make it all depend on the CONFIG option so all archs
+ * will work as long as the CONFIG is not set.	Once an 
+ * arch defines the CONFIG, it had better have the 
+ * asm/hrtime.h file in place.
+ */
+
+/*
+ * This gets filled in at init time, either static or dynamic.
+ * Someday this will be what NTP fiddles with.
+ * Do we need the scale here?  I don't think so, as long as we
+ * do percentage offsets for NTP.
+ */
+struct timer_conversion_bits {
+	unsigned long _arch_to_usec;
+	unsigned long _arch_to_nsec;
+	unsigned long _usec_to_arch;
+	unsigned long _nsec_to_arch;
+	long _cycles_per_jiffies;
+	unsigned long _arch_to_latch;
+};
+extern struct timer_conversion_bits timer_conversion_bits;
+/*
+ * The following four values are not used for machines 
+ * without a TSC.  For machines with a TSC they
+ * are caculated at boot time. They are used to 
+ * calculate "cycles" to jiffies or usec.  Don't get
+ * confused into thinking they are simple multiples or
+ * divisors, however.  
+ */
+#define arch_to_usec timer_conversion_bits._arch_to_usec
+#define arch_to_nsec timer_conversion_bits._arch_to_nsec
+#define usec_to_arch timer_conversion_bits._usec_to_arch
+#define nsec_to_arch timer_conversion_bits._nsec_to_arch
+#define cycles_per_jiffies timer_conversion_bits._cycles_per_jiffies
+#define arch_to_latch timer_conversion_bits._arch_to_latch
+
+#include <linux/config.h>
+#ifdef CONFIG_HIGH_RES_TIMERS
+#include <asm/hrtime.h>
+/*
+ * The schedule_next_int function is to be defined by the "arch" code
+ * when an "arch" is implementing the high-res part of POSIX timers.
+ * The actual function will be called with the offset in "arch" (parm 2)
+ * defined sub_jiffie units from the reference jiffie boundry (parm 1)to
+ * the next required sub_jiffie timer interrupt. This value will be -1
+ * if the next timer interrupt should be the next jiffie value.	 The
+ * "arch" code must determine how far out the interrupt is, based on
+ * current jiffie, sub_jiffie time and set up the hardware to interrupt
+ * at that time.  It is possible that the time will already have passed,
+ * in which case the function should return true (no interrupt is
+ * needed), otherwise the return should be 0.  The third parameter is the
+ * "always" flag which says that the code needs an interrupt, even if the
+ * time has passed.  In this case a "close" in time should be used to 
+ * generate the required interrupt.  The sub_jiffie interrupt
+ * should just call do_timer(). If the interrupt code ususally does stuff
+ * each jiffie, a flag should be kept by the jiffies update code to
+ * indicate that a new jiffie has started.  This flag is to keep this code 
+ * from being executed on the sub jiffie interrupt.
+ */
+#ifndef schedule_next_int
+#define schedule_next_int(s,d,a) 0
+#undef CONFIG_HIGH_RES_TIMERS
+#endif				// schedule_next_int
+/*
+ * The sub_jiffie() macro should return the current time offset from the latest
+ * jiffie.  This will be in "arch" defined units and is used to determine if
+ * a timer has expired.	 Since no sub_expire value will be used if "arch" 
+ * has not defined the high-res package, 0 will work well here.
+ *
+ * In addition, to save time if there is no high-res package (or it is not
+ * configured), we define the sub expression for the run_timer_list.
+ */
+
+#ifndef sub_jiffie
+#undef CONFIG_HIGH_RES_TIMERS
+#define sub_jiffie() 0
+#endif				// sub_jiffie
+
+/*
+ * The high_res_test() macro should set up a test mode that will do a
+ * worst case timer interrupt.	I.e. it may be that a call to 
+ * schedule_next_int() could return -1 indicating that the time has
+ * already expired.  This macro says to set it so that schedule_next_int()
+ * will always set up a timer interrupt.  This is used during init to
+ * calculate the worst case loop time from timer set up to int to 
+ * the signal code.
+
+ * high_res_end_test() cancels the above state and allows the no
+ * interrupt return from schedule_next_int()
+ */
+#ifndef high_res_test
+#define high_res_test()
+#define high_res_end_test()
+#endif
+
+#define IF_HIGH_RES(a) a
+
+#else				/*  CONFIG_HIGH_RES_TIMERS */
+#define IF_HIGH_RES(a)
+#define nsec_to_arch_cycles(a) 0
+
+#define discipline_timer(cpu)
+#define compute_latch(calibration_result)
+#endif				/*  CONFIG_HIGH_RES_TIMERS */
+
+/*
+ * Here is an SMP helping macro...
+ */
+#ifdef CONFIG_SMP
+#define IF_SMP(a) a
+#else
+#define IF_SMP(a)
+#endif
+/*
+ * These should have been defined in the platform hrtimers.h
+ * If not (or HIGH_RES_TIMERS not configured) define the default.
+ */
+#ifndef update_jiffies
+extern u64 jiffies_64;
+#define update_jiffies() (*(u64 *)&jiffies_64)++
+#endif
+#ifndef new_jiffie
+#define new_jiffie() 0
+#endif
+#ifndef schedule_next_int
+#define schedule_next_int(a,b,c)
+#endif
+/*
+ * If we included a high-res file, we may have gotten a more efficient 
+ * u64/u32, u64%u32 routine.  The one in div64.h actually handles a 
+ * u64 result, something we don't need, and, since it is more expensive
+ * arch porters are encouraged to implement the div_long_long_rem().
+ *
+ * int div_long_long_rem(u64 dividend,int divisor,int* remainder)
+ * which returns dividend/divisor.
+ * 
+ * Here we provide default code for those who, for what ever reason,
+ * have not provided the above.
+ */
+#ifndef div_long_long_rem
+#include <asm/div64.h>
+
+#define div_long_long_rem(dividend,divisor,remainder) ({ \
+		       u64 result = dividend;		\
+		       *remainder = do_div(result,divisor); \
+		       result; })
+
+#endif				/* ifndef div_long_long_rem */
+
+#endif				/* _HRTIME_H  */

diff -urP -I \$Id:.*Exp \$ -X /usr/src/patch.exclude linux-2.5.54-bk1-posix/include/linux/time.h linux/include/linux/time.h
@@ -1,7 +1,7 @@
 #ifndef _LINUX_TIME_H
 #define _LINUX_TIME_H
 
-#include <asm/param.h>
+#include <linux/param.h>
 #include <linux/types.h>
 
 #ifndef _STRUCT_TIMESPEC

@@ -53,6 +53,19 @@
 #define NSEC_PER_USEC (1000L)
 #endif
 
+/* Parameters used to convert the timespec values */
+#ifndef USEC_PER_SEC
+#define USEC_PER_SEC (1000000L)
+#endif
+
+#ifndef NSEC_PER_SEC
+#define NSEC_PER_SEC (1000000000L)
+#endif
+
+#ifndef NSEC_PER_USEC
+#define NSEC_PER_USEC (1000L)
+#endif
+
 static __inline__ unsigned long
 timespec_to_jiffies(struct timespec *value)
 {

@@ -61,16 +74,16 @@
 
 	if (sec >= (MAX_JIFFY_OFFSET / HZ))
 		return MAX_JIFFY_OFFSET;
-	nsec += 1000000000L / HZ - 1;
-	nsec /= 1000000000L / HZ;
+	nsec += NSEC_PER_SEC / HZ - 1;
+	nsec /= NSEC_PER_SEC / HZ;
 	return HZ * sec + nsec;
 }
 
 static __inline__ void
-jiffies_to_timespec(unsigned long jiffies, struct timespec *value)
+jiffies_to_timespec(unsigned long _jiffies, struct timespec *value)
 {
-	value->tv_nsec = (jiffies % HZ) * (1000000000L / HZ);
-	value->tv_sec = jiffies / HZ;
+	value->tv_nsec = (_jiffies % HZ) * (NSEC_PER_SEC / HZ);
+	value->tv_sec = _jiffies / HZ;
 }
 
 /* Same for "timeval" */

@@ -171,9 +184,9 @@
 #define	ITIMER_VIRTUAL	1
 #define	ITIMER_PROF	2
 
-struct  itimerspec {
-        struct  timespec it_interval;    /* timer period */
-        struct  timespec it_value;       /* timer expiration */
+struct	itimerspec {
+	struct	timespec it_interval;	 /* timer period */
+	struct	timespec it_value;	 /* timer expiration */
 };
 
 struct	itimerval {

diff -urP -I \$Id:.*Exp \$ -X /usr/src/patch.exclude linux-2.5.54-bk1-posix/include/linux/timer.h linux/include/linux/timer.h
@@ -18,6 +18,7 @@
 	unsigned long data;
 
 	struct tvec_t_base_s *base;
+	long sub_expires;
 };
 
 #define TIMER_MAGIC	0x4b87ad6e

@@ -29,6 +30,7 @@
 		.base = NULL,					\
 		.magic = TIMER_MAGIC,				\
 		.lock = SPIN_LOCK_UNLOCKED,			\
+		.sub_expires = 0,			        \
 	}
 
 /***

@@ -41,6 +43,7 @@
 static inline void init_timer(struct timer_list * timer)
 {
 	timer->base = NULL;
+	timer->sub_expires = 0;
 	timer->magic = TIMER_MAGIC;
 	spin_lock_init(&timer->lock);
 }

@@ -64,6 +67,7 @@
 extern void add_timer_on(struct timer_list *timer, int cpu);
 extern int del_timer(struct timer_list * timer);
 extern int mod_timer(struct timer_list *timer, unsigned long expires);
+extern void update_real_wall_time(void);
   
 #if CONFIG_SMP
   extern int del_timer_sync(struct timer_list * timer);

diff -urP -I \$Id:.*Exp \$ -X /usr/src/patch.exclude linux-2.5.54-bk1-posix/kernel/ksyms.c linux/kernel/ksyms.c
@@ -56,6 +56,7 @@
 #include <linux/mount.h>
 #include <linux/ptrace.h>
 #include <asm/checksum.h>
+#include <linux/hrtime.h>
 
 #if defined(CONFIG_PROC_FS)
 #include <linux/proc_fs.h>

@@ -484,6 +485,9 @@
 #endif
 EXPORT_SYMBOL(jiffies);
 EXPORT_SYMBOL(jiffies_64);
+#ifdef CONFIG_HIGH_RES_TIMERS
+EXPORT_SYMBOL(timer_conversion_bits);
+#endif
 EXPORT_SYMBOL(xtime);
 EXPORT_SYMBOL(do_gettimeofday);
 EXPORT_SYMBOL(do_settimeofday);

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