NTP: move the cmos update code into ntp.c

i386 and sparc64 have the identical code to update the cmos clock. Move it into kernel/time/ntp.c as there are other architectures coming along with the same requirements. [akpm@linux-foundation.org: build fixes] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Chris Wright <chrisw@sous-sol.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: john stultz <johnstul@us.ibm.com> Cc: David Miller <davem@davemloft.net> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

NTP: move the cmos update code into ntp.c
i386 and sparc64 have the identical code to update the cmos clock. Move it into kernel/time/ntp.c as there are other architectures coming along with the same requirements. [akpm@linux-foundation.org: build fixes] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Chris Wright <chrisw@sous-sol.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: john stultz <johnstul@us.ibm.com> Cc: David Miller <davem@davemloft.net> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Thomas Gleixner · Linus Torvalds
1 parent 99bc2fcb28
Showing 7 changed files with 71 additions and 103 deletions Side-by-side Diff
arch/i386/Kconfig
arch/i386/kernel/time.c
arch/sparc64/Kconfig
arch/sparc64/kernel/time.c
include/asm-i386/timer.h
include/linux/time.h
kernel/time/ntp.c
@@ -18,6 +18,10 @@
 	bool
 	default y
  
+config GENERIC_CMOS_UPDATE
+	bool
+	default y
+
 config CLOCKSOURCE_WATCHDOG
 	bool
 	default y
@@ -207,55 +207,9 @@
 	return retval;
 }
  
-static void sync_cmos_clock(unsigned long dummy);
-
-static DEFINE_TIMER(sync_cmos_timer, sync_cmos_clock, 0, 0);
-int no_sync_cmos_clock;
-
-static void sync_cmos_clock(unsigned long dummy)
+int update_persistent_clock(struct timespec now)
 {
-	struct timeval now, next;
-	int fail = 1;
-
-	/*
-	 * If we have an externally synchronized Linux clock, then update
-	 * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
-	 * called as close as possible to 500 ms before the new second starts.
-	 * This code is run on a timer.  If the clock is set, that timer
-	 * may not expire at the correct time.  Thus, we adjust...
-	 */
-	if (!ntp_synced())
-		/*
-		 * Not synced, exit, do not restart a timer (if one is
-		 * running, let it run out).
-		 */
-		return;
-
-	do_gettimeofday(&now);
-	if (now.tv_usec >= USEC_AFTER - ((unsigned) TICK_SIZE) / 2 &&
-	    now.tv_usec <= USEC_BEFORE + ((unsigned) TICK_SIZE) / 2)
-		fail = set_rtc_mmss(now.tv_sec);
-
-	next.tv_usec = USEC_AFTER - now.tv_usec;
-	if (next.tv_usec <= 0)
-		next.tv_usec += USEC_PER_SEC;
-
-	if (!fail)
-		next.tv_sec = 659;
-	else
-		next.tv_sec = 0;
-
-	if (next.tv_usec >= USEC_PER_SEC) {
-		next.tv_sec++;
-		next.tv_usec -= USEC_PER_SEC;
-	}
-	mod_timer(&sync_cmos_timer, jiffies + timeval_to_jiffies(&next));
-}
-
-void notify_arch_cmos_timer(void)
-{
-	if (!no_sync_cmos_clock)
-		mod_timer(&sync_cmos_timer, jiffies + 1);
+	return set_rtc_mmss(now.tv_sec);
 }
  
 extern void (*late_time_init)(void);
@@ -23,6 +23,10 @@
 	bool
 	default y
  
+config GENERIC_CMOS_UPDATE
+	bool
+	default y
+
 config GENERIC_CLOCKEVENTS
 	bool
 	default y
@@ -403,58 +403,9 @@
  
 static unsigned long timer_ticks_per_nsec_quotient __read_mostly;
  
-#define TICK_SIZE (tick_nsec / 1000)
-
-#define USEC_AFTER	500000
-#define USEC_BEFORE	500000
-
-static void sync_cmos_clock(unsigned long dummy);
-
-static DEFINE_TIMER(sync_cmos_timer, sync_cmos_clock, 0, 0);
-
-static void sync_cmos_clock(unsigned long dummy)
+int update_persistent_clock(struct timespec now)
 {
-	struct timeval now, next;
-	int fail = 1;
-
-	/*
-	 * If we have an externally synchronized Linux clock, then update
-	 * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
-	 * called as close as possible to 500 ms before the new second starts.
-	 * This code is run on a timer.  If the clock is set, that timer
-	 * may not expire at the correct time.  Thus, we adjust...
-	 */
-	if (!ntp_synced())
-		/*
-		 * Not synced, exit, do not restart a timer (if one is
-		 * running, let it run out).
-		 */
-		return;
-
-	do_gettimeofday(&now);
-	if (now.tv_usec >= USEC_AFTER - ((unsigned) TICK_SIZE) / 2 &&
-	    now.tv_usec <= USEC_BEFORE + ((unsigned) TICK_SIZE) / 2)
-		fail = set_rtc_mmss(now.tv_sec);
-
-	next.tv_usec = USEC_AFTER - now.tv_usec;
-	if (next.tv_usec <= 0)
-		next.tv_usec += USEC_PER_SEC;
-
-	if (!fail)
-		next.tv_sec = 659;
-	else
-		next.tv_sec = 0;
-
-	if (next.tv_usec >= USEC_PER_SEC) {
-		next.tv_sec++;
-		next.tv_usec -= USEC_PER_SEC;
-	}
-	mod_timer(&sync_cmos_timer, jiffies + timeval_to_jiffies(&next));
-}
-
-void notify_arch_cmos_timer(void)
-{
-	mod_timer(&sync_cmos_timer, jiffies + 1);
+	return set_rtc_mmss(now.tv_sec);
 }
  
 /* Kick start a stopped clock (procedure from the Sun NVRAM/hostid FAQ). */
@@ -11,7 +11,6 @@
  
 extern int timer_ack;
 extern int no_timer_check;
-extern int no_sync_cmos_clock;
 extern int recalibrate_cpu_khz(void);
  
 #ifndef CONFIG_PARAVIRT
@@ -4,6 +4,7 @@
 #include <linux/types.h>
  
 #ifdef __KERNEL__
+# include <linux/cache.h>
 # include <linux/seqlock.h>
 #endif
  
@@ -94,6 +95,8 @@
 extern seqlock_t xtime_lock __attribute__((weak));
  
 extern unsigned long read_persistent_clock(void);
+extern int update_persistent_clock(struct timespec now);
+extern int no_sync_cmos_clock __read_mostly;
 void timekeeping_init(void);
  
 static inline unsigned long get_seconds(void)
@@ -10,6 +10,7 @@
  
 #include <linux/mm.h>
 #include <linux/time.h>
+#include <linux/timer.h>
 #include <linux/timex.h>
 #include <linux/jiffies.h>
 #include <linux/hrtimer.h>
  
  
  
@@ -175,12 +176,64 @@
 	return tick_length;
 }
  
+#ifdef CONFIG_GENERIC_CMOS_UPDATE
  
-void __attribute__ ((weak)) notify_arch_cmos_timer(void)
+/* Disable the cmos update - used by virtualization and embedded */
+int no_sync_cmos_clock  __read_mostly;
+
+static void sync_cmos_clock(unsigned long dummy);
+
+static DEFINE_TIMER(sync_cmos_timer, sync_cmos_clock, 0, 0);
+
+static void sync_cmos_clock(unsigned long dummy)
 {
-	return;
+	struct timespec now, next;
+	int fail = 1;
+
+	/*
+	 * If we have an externally synchronized Linux clock, then update
+	 * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
+	 * called as close as possible to 500 ms before the new second starts.
+	 * This code is run on a timer.  If the clock is set, that timer
+	 * may not expire at the correct time.  Thus, we adjust...
+	 */
+	if (!ntp_synced())
+		/*
+		 * Not synced, exit, do not restart a timer (if one is
+		 * running, let it run out).
+		 */
+		return;
+
+	getnstimeofday(&now);
+	if (abs(xtime.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec / 2)
+		fail = update_persistent_clock(now);
+
+	next.tv_nsec = (NSEC_PER_SEC / 2) - now.tv_nsec;
+	if (next.tv_nsec <= 0)
+		next.tv_nsec += NSEC_PER_SEC;
+
+	if (!fail)
+		next.tv_sec = 659;
+	else
+		next.tv_sec = 0;
+
+	if (next.tv_nsec >= NSEC_PER_SEC) {
+		next.tv_sec++;
+		next.tv_nsec -= NSEC_PER_SEC;
+	}
+	mod_timer(&sync_cmos_timer, jiffies + timespec_to_jiffies(&next));
 }
  
+static void notify_cmos_timer(void)
+{
+	if (no_sync_cmos_clock)
+		mod_timer(&sync_cmos_timer, jiffies + 1);
+}
+
+#else
+static inline void notify_cmos_timer(void) { }
+#endif
+
 /* adjtimex mainly allows reading (and writing, if superuser) of
  * kernel time-keeping variables. used by xntpd.
  */
@@ -345,7 +398,7 @@
 	txc->stbcnt	   = 0;
 	write_sequnlock_irq(&xtime_lock);
 	do_gettimeofday(&txc->time);
-	notify_arch_cmos_timer();
+	notify_cmos_timer();
 	return(result);
 }
...	...	@@ -18,6 +18,10 @@
18	18	bool
19	19	default y
20	20
	21	+config GENERIC_CMOS_UPDATE
	22	+ bool
	23	+ default y
	24	+
21	25	config CLOCKSOURCE_WATCHDOG
22	26	bool
23	27	default y
...	...	@@ -207,55 +207,9 @@
207	207	return retval;
208	208	}
209	209
210		-static void sync_cmos_clock(unsigned long dummy);
211		-
212		-static DEFINE_TIMER(sync_cmos_timer, sync_cmos_clock, 0, 0);
213		-int no_sync_cmos_clock;
214		-
215		-static void sync_cmos_clock(unsigned long dummy)
	210	+int update_persistent_clock(struct timespec now)
216	211	{
217		- struct timeval now, next;
218		- int fail = 1;
219		-
220		- /*
221		- * If we have an externally synchronized Linux clock, then update
222		- * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
223		- * called as close as possible to 500 ms before the new second starts.
224		- * This code is run on a timer. If the clock is set, that timer
225		- * may not expire at the correct time. Thus, we adjust...
226		- */
227		- if (!ntp_synced())
228		- /*
229		- * Not synced, exit, do not restart a timer (if one is
230		- * running, let it run out).
231		- */
232		- return;
233		-
234		- do_gettimeofday(&now);
235		- if (now.tv_usec >= USEC_AFTER - ((unsigned) TICK_SIZE) / 2 &&
236		- now.tv_usec <= USEC_BEFORE + ((unsigned) TICK_SIZE) / 2)
237		- fail = set_rtc_mmss(now.tv_sec);
238		-
239		- next.tv_usec = USEC_AFTER - now.tv_usec;
240		- if (next.tv_usec <= 0)
241		- next.tv_usec += USEC_PER_SEC;
242		-
243		- if (!fail)
244		- next.tv_sec = 659;
245		- else
246		- next.tv_sec = 0;
247		-
248		- if (next.tv_usec >= USEC_PER_SEC) {
249		- next.tv_sec++;
250		- next.tv_usec -= USEC_PER_SEC;
251		- }
252		- mod_timer(&sync_cmos_timer, jiffies + timeval_to_jiffies(&next));
253		-}
254		-
255		-void notify_arch_cmos_timer(void)
256		-{
257		- if (!no_sync_cmos_clock)
258		- mod_timer(&sync_cmos_timer, jiffies + 1);
	212	+ return set_rtc_mmss(now.tv_sec);
259	213	}
260	214
261	215	extern void (*late_time_init)(void);
...	...	@@ -23,6 +23,10 @@
23	23	bool
24	24	default y
25	25
	26	+config GENERIC_CMOS_UPDATE
	27	+ bool
	28	+ default y
	29	+
26	30	config GENERIC_CLOCKEVENTS
27	31	bool
28	32	default y
...	...	@@ -403,58 +403,9 @@
403	403
404	404	static unsigned long timer_ticks_per_nsec_quotient __read_mostly;
405	405
406		-#define TICK_SIZE (tick_nsec / 1000)
407		-
408		-#define USEC_AFTER 500000
409		-#define USEC_BEFORE 500000
410		-
411		-static void sync_cmos_clock(unsigned long dummy);
412		-
413		-static DEFINE_TIMER(sync_cmos_timer, sync_cmos_clock, 0, 0);
414		-
415		-static void sync_cmos_clock(unsigned long dummy)
	406	+int update_persistent_clock(struct timespec now)
416	407	{
417		- struct timeval now, next;
418		- int fail = 1;
419		-
420		- /*
421		- * If we have an externally synchronized Linux clock, then update
422		- * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
423		- * called as close as possible to 500 ms before the new second starts.
424		- * This code is run on a timer. If the clock is set, that timer
425		- * may not expire at the correct time. Thus, we adjust...
426		- */
427		- if (!ntp_synced())
428		- /*
429		- * Not synced, exit, do not restart a timer (if one is
430		- * running, let it run out).
431		- */
432		- return;
433		-
434		- do_gettimeofday(&now);
435		- if (now.tv_usec >= USEC_AFTER - ((unsigned) TICK_SIZE) / 2 &&
436		- now.tv_usec <= USEC_BEFORE + ((unsigned) TICK_SIZE) / 2)
437		- fail = set_rtc_mmss(now.tv_sec);
438		-
439		- next.tv_usec = USEC_AFTER - now.tv_usec;
440		- if (next.tv_usec <= 0)
441		- next.tv_usec += USEC_PER_SEC;
442		-
443		- if (!fail)
444		- next.tv_sec = 659;
445		- else
446		- next.tv_sec = 0;
447		-
448		- if (next.tv_usec >= USEC_PER_SEC) {
449		- next.tv_sec++;
450		- next.tv_usec -= USEC_PER_SEC;
451		- }
452		- mod_timer(&sync_cmos_timer, jiffies + timeval_to_jiffies(&next));
453		-}
454		-
455		-void notify_arch_cmos_timer(void)
456		-{
457		- mod_timer(&sync_cmos_timer, jiffies + 1);
	408	+ return set_rtc_mmss(now.tv_sec);
458	409	}
459	410
460	411	/* Kick start a stopped clock (procedure from the Sun NVRAM/hostid FAQ). */
...	...	@@ -11,7 +11,6 @@
11	11
12	12	extern int timer_ack;
13	13	extern int no_timer_check;
14		-extern int no_sync_cmos_clock;
15	14	extern int recalibrate_cpu_khz(void);
16	15
17	16	#ifndef CONFIG_PARAVIRT
...	...	@@ -4,6 +4,7 @@
4	4	#include <linux/types.h>
5	5
6	6	#ifdef __KERNEL__
	7	+# include <linux/cache.h>
7	8	# include <linux/seqlock.h>
8	9	#endif
9	10
...	...	@@ -94,6 +95,8 @@
94	95	extern seqlock_t xtime_lock __attribute__((weak));
95	96
96	97	extern unsigned long read_persistent_clock(void);
	98	+extern int update_persistent_clock(struct timespec now);
	99	+extern int no_sync_cmos_clock __read_mostly;
97	100	void timekeeping_init(void);
98	101
99	102	static inline unsigned long get_seconds(void)
...	...	@@ -10,6 +10,7 @@
10	10
11	11	#include <linux/mm.h>
12	12	#include <linux/time.h>
	13	+#include <linux/timer.h>
13	14	#include <linux/timex.h>
14	15	#include <linux/jiffies.h>
15	16	#include <linux/hrtimer.h>
16	17
17	18
18	19
...	...	@@ -175,12 +176,64 @@
175	176	return tick_length;
176	177	}
177	178
	179	+#ifdef CONFIG_GENERIC_CMOS_UPDATE
178	180
179		-void __attribute__ ((weak)) notify_arch_cmos_timer(void)
	181	+/* Disable the cmos update - used by virtualization and embedded */
	182	+int no_sync_cmos_clock __read_mostly;
	183	+
	184	+static void sync_cmos_clock(unsigned long dummy);
	185	+
	186	+static DEFINE_TIMER(sync_cmos_timer, sync_cmos_clock, 0, 0);
	187	+
	188	+static void sync_cmos_clock(unsigned long dummy)
180	189	{
181		- return;
	190	+ struct timespec now, next;
	191	+ int fail = 1;
	192	+
	193	+ /*
	194	+ * If we have an externally synchronized Linux clock, then update
	195	+ * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
	196	+ * called as close as possible to 500 ms before the new second starts.
	197	+ * This code is run on a timer. If the clock is set, that timer
	198	+ * may not expire at the correct time. Thus, we adjust...
	199	+ */
	200	+ if (!ntp_synced())
	201	+ /*
	202	+ * Not synced, exit, do not restart a timer (if one is
	203	+ * running, let it run out).
	204	+ */
	205	+ return;
	206	+
	207	+ getnstimeofday(&now);
	208	+ if (abs(xtime.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec / 2)
	209	+ fail = update_persistent_clock(now);
	210	+
	211	+ next.tv_nsec = (NSEC_PER_SEC / 2) - now.tv_nsec;
	212	+ if (next.tv_nsec <= 0)
	213	+ next.tv_nsec += NSEC_PER_SEC;
	214	+
	215	+ if (!fail)
	216	+ next.tv_sec = 659;
	217	+ else
	218	+ next.tv_sec = 0;
	219	+
	220	+ if (next.tv_nsec >= NSEC_PER_SEC) {
	221	+ next.tv_sec++;
	222	+ next.tv_nsec -= NSEC_PER_SEC;
	223	+ }
	224	+ mod_timer(&sync_cmos_timer, jiffies + timespec_to_jiffies(&next));
182	225	}
183	226
	227	+static void notify_cmos_timer(void)
	228	+{
	229	+ if (no_sync_cmos_clock)
	230	+ mod_timer(&sync_cmos_timer, jiffies + 1);
	231	+}
	232	+
	233	+#else
	234	+static inline void notify_cmos_timer(void) { }
	235	+#endif
	236	+
184	237	/* adjtimex mainly allows reading (and writing, if superuser) of
185	238	* kernel time-keeping variables. used by xntpd.
186	239	*/
...	...	@@ -345,7 +398,7 @@
345	398	txc->stbcnt = 0;
346	399	write_sequnlock_irq(&xtime_lock);
347	400	do_gettimeofday(&txc->time);
348		- notify_arch_cmos_timer();
	401	+ notify_cmos_timer();
349	402	return(result);
350	403	}