Merge git://git.kernel.org/pub/scm/linux/kernel/git/tglx/linux-2.6-hrt
authorLinus Torvalds <torvalds@woody.linux-foundation.org>
Sun, 9 Mar 2008 17:06:49 +0000 (10:06 -0700)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Sun, 9 Mar 2008 17:06:49 +0000 (10:06 -0700)
* git://git.kernel.org/pub/scm/linux/kernel/git/tglx/linux-2.6-hrt:
  time: remove obsolete CLOCK_TICK_ADJUST
  time: don't touch an offlined CPU's ts->tick_stopped in tick_cancel_sched_timer()
  time: prevent the loop in timespec_add_ns() from being optimised away
  ntp: use unsigned input for do_div()

include/linux/time.h
include/linux/timex.h
kernel/time/ntp.c
kernel/time/tick-sched.c
kernel/time/timekeeping.c

index 2091a19f1655aab8e5130256f83af4103efa9e3f..d32ef0ad4c0aaf8964d94abe215c5dbf4dde8aaf 100644 (file)
@@ -174,6 +174,10 @@ static inline void timespec_add_ns(struct timespec *a, u64 ns)
 {
        ns += a->tv_nsec;
        while(unlikely(ns >= NSEC_PER_SEC)) {
+               /* The following asm() prevents the compiler from
+                * optimising this loop into a modulo operation.  */
+               asm("" : "+r"(ns));
+
                ns -= NSEC_PER_SEC;
                a->tv_sec++;
        }
index c3f374786a4358e59eb6ce72e3b436e6a2556449..8ea3e71ba7fa8ff17d8de5587f482450c349ef36 100644 (file)
@@ -232,14 +232,7 @@ static inline int ntp_synced(void)
 #else
 #define NTP_INTERVAL_FREQ  (HZ)
 #endif
-
-#define CLOCK_TICK_OVERFLOW    (LATCH * HZ - CLOCK_TICK_RATE)
-#define CLOCK_TICK_ADJUST      (((s64)CLOCK_TICK_OVERFLOW * NSEC_PER_SEC) / \
-                                       (s64)CLOCK_TICK_RATE)
-
-/* Because using NSEC_PER_SEC would be too easy */
-#define NTP_INTERVAL_LENGTH ((((s64)TICK_USEC * NSEC_PER_USEC * USER_HZ) + \
-                             CLOCK_TICK_ADJUST) / NTP_INTERVAL_FREQ)
+#define NTP_INTERVAL_LENGTH (NSEC_PER_SEC/NTP_INTERVAL_FREQ)
 
 /* Returns how long ticks are at present, in ns / 2^(SHIFT_SCALE-10). */
 extern u64 current_tick_length(void);
index c88b5910e7abb9c630106fcbf21b6b7a0d363faf..5fd9b946977038cbdc192dc5a11146696ad53947 100644 (file)
@@ -42,12 +42,13 @@ long time_esterror = NTP_PHASE_LIMIT;       /* estimated error (us)         */
 long time_freq;                                /* frequency offset (scaled ppm)*/
 static long time_reftime;              /* time at last adjustment (s)  */
 long time_adjust;
+static long ntp_tick_adj;
 
 static void ntp_update_frequency(void)
 {
        u64 second_length = (u64)(tick_usec * NSEC_PER_USEC * USER_HZ)
                                << TICK_LENGTH_SHIFT;
-       second_length += (s64)CLOCK_TICK_ADJUST << TICK_LENGTH_SHIFT;
+       second_length += (s64)ntp_tick_adj << TICK_LENGTH_SHIFT;
        second_length += (s64)time_freq << (TICK_LENGTH_SHIFT - SHIFT_NSEC);
 
        tick_length_base = second_length;
@@ -342,14 +343,16 @@ int do_adjtimex(struct timex *txc)
                    freq_adj = shift_right(freq_adj, time_constant * 2 +
                                           (SHIFT_PLL + 2) * 2 - SHIFT_NSEC);
                    if (mtemp >= MINSEC && (time_status & STA_FLL || mtemp > MAXSEC)) {
+                       u64 utemp64;
                        temp64 = time_offset << (SHIFT_NSEC - SHIFT_FLL);
                        if (time_offset < 0) {
-                           temp64 = -temp64;
-                           do_div(temp64, mtemp);
-                           freq_adj -= temp64;
+                           utemp64 = -temp64;
+                           do_div(utemp64, mtemp);
+                           freq_adj -= utemp64;
                        } else {
-                           do_div(temp64, mtemp);
-                           freq_adj += temp64;
+                           utemp64 = temp64;
+                           do_div(utemp64, mtemp);
+                           freq_adj += utemp64;
                        }
                    }
                    freq_adj += time_freq;
@@ -400,3 +403,11 @@ leave:     if ((time_status & (STA_UNSYNC|STA_CLOCKERR)) != 0)
        notify_cmos_timer();
        return(result);
 }
+
+static int __init ntp_tick_adj_setup(char *str)
+{
+       ntp_tick_adj = simple_strtol(str, NULL, 0);
+       return 1;
+}
+
+__setup("ntp_tick_adj=", ntp_tick_adj_setup);
index 2968298f8f364923010c440fe68f6e02d2f32e2a..686da821d376b01dd21d379bfd8baf39d6b106f1 100644 (file)
@@ -640,7 +640,7 @@ void tick_cancel_sched_timer(int cpu)
 
        if (ts->sched_timer.base)
                hrtimer_cancel(&ts->sched_timer);
-       ts->tick_stopped = 0;
+
        ts->nohz_mode = NOHZ_MODE_INACTIVE;
 }
 #endif /* HIGH_RES_TIMERS */
index 1af9fb050fe28b1e77ae9f43c3005e16972b2d65..671af612b7684ed27578ae3db8445f71f3499059 100644 (file)
@@ -187,8 +187,7 @@ static void change_clocksource(void)
 
        clock->error = 0;
        clock->xtime_nsec = 0;
-       clocksource_calculate_interval(clock,
-               (unsigned long)(current_tick_length()>>TICK_LENGTH_SHIFT));
+       clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH);
 
        tick_clock_notify();
 
@@ -245,8 +244,7 @@ void __init timekeeping_init(void)
        ntp_clear();
 
        clock = clocksource_get_next();
-       clocksource_calculate_interval(clock,
-               (unsigned long)(current_tick_length()>>TICK_LENGTH_SHIFT));
+       clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH);
        clock->cycle_last = clocksource_read(clock);
 
        xtime.tv_sec = sec;