X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fs390%2Fkernel%2Ftime.c;h=2a6c6efb68653db8880853d09648d86f21af60b9;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=8f279421646f6da5809c9e7fd6b32c076b6e4551;hpb=c7b5ebbddf7bcd3651947760f423e3783bbe6573;p=linux-2.6.git

diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c
index 8f2794216..2a6c6efb6 100644
--- a/arch/s390/kernel/time.c
+++ b/arch/s390/kernel/time.c
@@ -49,10 +49,6 @@
 
 #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;
@@ -65,8 +61,17 @@ extern unsigned long wall_jiffies;
  */
 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)
 {
@@ -139,10 +144,7 @@ int do_settimeofday(struct timespec *tv)
 	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;
+	ntp_clear();
 	write_sequnlock_irq(&xtime_lock);
 	clock_was_set();
 	return 0;
@@ -150,28 +152,6 @@ int do_settimeofday(struct timespec *tv)
 
 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)
@@ -187,14 +167,23 @@ __calculate_ticks(__u64 elapsed)
 void account_ticks(struct pt_regs *regs)
 {
 	__u64 tmp;
-	__u32 ticks;
+	__u32 ticks, xticks;
 
 	/* 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) {
@@ -216,11 +205,9 @@ void account_ticks(struct pt_regs *regs)
 	 */
 	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;
@@ -230,12 +217,18 @@ void account_ticks(struct pt_regs *regs)
 			do_timer(regs);
 	}
 	write_sequnlock(&xtime_lock);
-	while (ticks--)
-		update_process_times(user_mode(regs));
 #else
-	while (ticks--)
+	for (xticks = ticks; xticks > 0; xticks--)
 		do_timer(regs);
 #endif
+
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+	account_tick_vtime(current);
+#else
+	while (ticks--)
+		update_process_times(user_mode(regs));
+#endif
+
 	s390_do_profile(regs);
 }
 
@@ -253,26 +246,42 @@ int sysctl_hz_timer = 1;
  */
 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));
 }
 
 /*
@@ -283,7 +292,7 @@ static inline void start_hz_timer(void)
 {
 	if (!cpu_isset(smp_processor_id(), nohz_cpu_mask))
 		return;
-	account_ticks(__KSTK_PTREGS(current));
+	account_ticks(task_pt_regs(current));
 	cpu_clear(smp_processor_id(), nohz_cpu_mask);
 }