* Copyright (C) 1991, 1992, 1995 Linus Torvalds
*/
-#include <linux/config.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/profile.h>
#include <linux/timex.h>
#include <linux/notifier.h>
+#include <linux/clocksource.h>
#include <asm/uaccess.h>
#include <asm/delay.h>
#include <asm/s390_ext.h>
#include <asm/div64.h>
#include <asm/irq.h>
+#include <asm/irq_regs.h>
#include <asm/timer.h>
/* change this if you have some constant time drift */
#define TICK_SIZE tick
-u64 jiffies_64 = INITIAL_JIFFIES;
-
-EXPORT_SYMBOL(jiffies_64);
-
static ext_int_info_t ext_int_info_cc;
static u64 init_timer_cc;
static u64 jiffies_timer_cc;
static u64 xtime_cc;
-extern unsigned long wall_jiffies;
-
/*
* Scheduler clock - returns current time in nanosec units.
*/
unsigned long long sched_clock(void)
{
- return ((get_clock() - jiffies_timer_cc) * 1000) >> 12;
+ return ((get_clock() - jiffies_timer_cc) * 125) >> 9;
}
+/*
+ * Monotonic_clock - returns # of nanoseconds passed since time_init()
+ */
+unsigned long long monotonic_clock(void)
+{
+ return sched_clock();
+}
+EXPORT_SYMBOL(monotonic_clock);
+
void tod_to_timeval(__u64 todval, struct timespec *xtime)
{
unsigned long long sec;
xtime->tv_nsec = ((todval * 1000) >> 12);
}
-static inline unsigned long do_gettimeoffset(void)
-{
- __u64 now;
-
- now = (get_clock() - jiffies_timer_cc) >> 12;
- /* We require the offset from the latest update of xtime */
- now -= (__u64) wall_jiffies*USECS_PER_JIFFY;
- return (unsigned long) now;
-}
-
-/*
- * This version of gettimeofday has microsecond resolution.
- */
-void do_gettimeofday(struct timeval *tv)
-{
- unsigned long flags;
- unsigned long seq;
- unsigned long usec, sec;
-
- do {
- seq = read_seqbegin_irqsave(&xtime_lock, flags);
-
- sec = xtime.tv_sec;
- usec = xtime.tv_nsec / 1000 + do_gettimeoffset();
- } while (read_seqretry_irqrestore(&xtime_lock, seq, flags));
-
- while (usec >= 1000000) {
- usec -= 1000000;
- sec++;
- }
-
- tv->tv_sec = sec;
- tv->tv_usec = usec;
-}
-
-EXPORT_SYMBOL(do_gettimeofday);
-
-int do_settimeofday(struct timespec *tv)
-{
- time_t wtm_sec, sec = tv->tv_sec;
- long wtm_nsec, nsec = tv->tv_nsec;
-
- if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
- return -EINVAL;
-
- write_seqlock_irq(&xtime_lock);
- /* This is revolting. We need to set the xtime.tv_nsec
- * correctly. However, the value in this location is
- * is value at the last tick.
- * Discover what correction gettimeofday
- * would have done, and then undo it!
- */
- nsec -= do_gettimeoffset() * 1000;
-
- wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec);
- wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec);
-
- set_normalized_timespec(&xtime, sec, nsec);
- set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec);
-
- time_adjust = 0; /* stop active adjtime() */
- time_status |= STA_UNSYNC;
- time_maxerror = NTP_PHASE_LIMIT;
- time_esterror = NTP_PHASE_LIMIT;
- write_sequnlock_irq(&xtime_lock);
- clock_was_set();
- return 0;
-}
-
-EXPORT_SYMBOL(do_settimeofday);
-
-#ifndef CONFIG_ARCH_S390X
-
-static inline __u32
-__calculate_ticks(__u64 elapsed)
-{
- register_pair rp;
-
- rp.pair = elapsed >> 1;
- asm ("dr %0,%1" : "+d" (rp) : "d" (CLK_TICKS_PER_JIFFY >> 1));
- return rp.subreg.odd;
-}
-
-#else /* CONFIG_ARCH_S390X */
-
-static inline __u32
-__calculate_ticks(__u64 elapsed)
-{
- return elapsed / CLK_TICKS_PER_JIFFY;
-}
-
-#endif /* CONFIG_ARCH_S390X */
-
-
#ifdef CONFIG_PROFILING
-#define s390_do_profile(regs) profile_tick(CPU_PROFILING, regs)
+#define s390_do_profile() profile_tick(CPU_PROFILING)
#else
-#define s390_do_profile(regs) do { ; } while(0)
+#define s390_do_profile() do { ; } while(0)
#endif /* CONFIG_PROFILING */
* timer_interrupt() needs to keep up the real-time clock,
* as well as call the "do_timer()" routine every clocktick
*/
-void account_ticks(struct pt_regs *regs)
+void account_ticks(void)
{
__u64 tmp;
__u32 ticks;
/* Calculate how many ticks have passed. */
- if (S390_lowcore.int_clock < S390_lowcore.jiffy_timer)
+ if (S390_lowcore.int_clock < S390_lowcore.jiffy_timer) {
+ /*
+ * We have to program the clock comparator even if
+ * no tick has passed. That happens if e.g. an i/o
+ * interrupt wakes up an idle processor that has
+ * switched off its hz timer.
+ */
+ tmp = S390_lowcore.jiffy_timer + CPU_DEVIATION;
+ asm volatile ("SCKC %0" : : "m" (tmp));
return;
+ }
tmp = S390_lowcore.int_clock - S390_lowcore.jiffy_timer;
if (tmp >= 2*CLK_TICKS_PER_JIFFY) { /* more than two ticks ? */
- ticks = __calculate_ticks(tmp) + 1;
+ ticks = __div(tmp, CLK_TICKS_PER_JIFFY) + 1;
S390_lowcore.jiffy_timer +=
CLK_TICKS_PER_JIFFY * (__u64) ticks;
} else if (tmp >= CLK_TICKS_PER_JIFFY) {
write_seqlock(&xtime_lock);
if (S390_lowcore.jiffy_timer > xtime_cc) {
__u32 xticks;
-
tmp = S390_lowcore.jiffy_timer - xtime_cc;
if (tmp >= 2*CLK_TICKS_PER_JIFFY) {
- xticks = __calculate_ticks(tmp);
+ xticks = __div(tmp, CLK_TICKS_PER_JIFFY);
xtime_cc += (__u64) xticks * CLK_TICKS_PER_JIFFY;
} else {
xticks = 1;
xtime_cc += CLK_TICKS_PER_JIFFY;
}
- while (xticks--)
- do_timer(regs);
+ do_timer(xticks);
}
write_sequnlock(&xtime_lock);
- while (ticks--)
- update_process_times(user_mode(regs));
+#else
+ do_timer(ticks);
+#endif
+
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+ account_tick_vtime(current);
#else
while (ticks--)
- do_timer(regs);
+ update_process_times(user_mode(get_irq_regs()));
#endif
- s390_do_profile(regs);
+
+ s390_do_profile();
}
#ifdef CONFIG_NO_IDLE_HZ
*/
static inline void stop_hz_timer(void)
{
- __u64 timer;
+ unsigned long flags;
+ unsigned long seq, next;
+ __u64 timer, todval;
+ int cpu = smp_processor_id();
if (sysctl_hz_timer != 0)
return;
+ cpu_set(cpu, nohz_cpu_mask);
+
/*
* Leave the clock comparator set up for the next timer
* tick if either rcu or a softirq is pending.
*/
- if (rcu_pending(smp_processor_id()) || local_softirq_pending())
+ if (rcu_needs_cpu(cpu) || local_softirq_pending()) {
+ cpu_clear(cpu, nohz_cpu_mask);
return;
+ }
/*
* This cpu is going really idle. Set up the clock comparator
* for the next event.
*/
- cpu_set(smp_processor_id(), nohz_cpu_mask);
- timer = (__u64) (next_timer_interrupt() - jiffies) + jiffies_64;
- timer = jiffies_timer_cc + timer * CLK_TICKS_PER_JIFFY;
- asm volatile ("SCKC %0" : : "m" (timer));
+ next = next_timer_interrupt();
+ do {
+ seq = read_seqbegin_irqsave(&xtime_lock, flags);
+ timer = ((__u64) next) - ((__u64) jiffies) + jiffies_64;
+ } while (read_seqretry_irqrestore(&xtime_lock, seq, flags));
+ todval = -1ULL;
+ /* Be careful about overflows. */
+ if (timer < (-1ULL / CLK_TICKS_PER_JIFFY)) {
+ timer = jiffies_timer_cc + timer * CLK_TICKS_PER_JIFFY;
+ if (timer >= jiffies_timer_cc)
+ todval = timer;
+ }
+ asm volatile ("SCKC %0" : : "m" (todval));
}
/*
*/
static inline void start_hz_timer(void)
{
+ BUG_ON(!in_interrupt());
+
if (!cpu_isset(smp_processor_id(), nohz_cpu_mask))
return;
- account_ticks(__KSTK_PTREGS(current));
+ account_ticks();
cpu_clear(smp_processor_id(), nohz_cpu_mask);
}
extern void vtime_init(void);
+static cycle_t read_tod_clock(void)
+{
+ return get_clock();
+}
+
+static struct clocksource clocksource_tod = {
+ .name = "tod",
+ .rating = 100,
+ .read = read_tod_clock,
+ .mask = -1ULL,
+ .mult = 1000,
+ .shift = 12,
+ .is_continuous = 1,
+};
+
+
/*
* Initialize the TOD clock and the CPU timer of
* the boot cpu.
int cc;
/* kick the TOD clock */
- asm volatile ("STCK 0(%1)\n\t"
- "IPM %0\n\t"
- "SRL %0,28" : "=r" (cc) : "a" (&init_timer_cc)
- : "memory", "cc");
+ asm volatile(
+ " stck 0(%2)\n"
+ " ipm %0\n"
+ " srl %0,28"
+ : "=d" (cc), "=m" (init_timer_cc)
+ : "a" (&init_timer_cc) : "cc");
switch (cc) {
case 0: /* clock in set state: all is fine */
break;
-xtime.tv_sec, -xtime.tv_nsec);
/* request the clock comparator external interrupt */
- if (register_early_external_interrupt(0x1004, 0,
+ if (register_early_external_interrupt(0x1004, NULL,
&ext_int_info_cc) != 0)
panic("Couldn't request external interrupt 0x1004");
+ if (clocksource_register(&clocksource_tod) != 0)
+ panic("Could not register TOD clock source");
+
init_cpu_timer();
#ifdef CONFIG_NO_IDLE_HZ