diff options
author | Dave Airlie <airlied@redhat.com> | 2009-03-28 20:22:18 -0400 |
---|---|---|
committer | Dave Airlie <airlied@redhat.com> | 2009-03-28 20:22:18 -0400 |
commit | 90f959bcb386da2c71613dcefc6a285e054a539e (patch) | |
tree | ee3e9dd4111d4aad12e579cb0c2c159114dff263 /kernel/time | |
parent | 41f13fe81dd1b08723ab9f3fc3c7f29cfa81f1a5 (diff) | |
parent | 07d43ba98621f08e252a48c96b258b4d572b0257 (diff) |
drm: merge Linux master into HEAD
Conflicts:
drivers/gpu/drm/drm_info.c
drivers/gpu/drm/drm_proc.c
drivers/gpu/drm/i915/i915_gem_debugfs.c
Diffstat (limited to 'kernel/time')
-rw-r--r-- | kernel/time/Makefile | 2 | ||||
-rw-r--r-- | kernel/time/clockevents.c | 20 | ||||
-rw-r--r-- | kernel/time/clocksource.c | 76 | ||||
-rw-r--r-- | kernel/time/ntp.c | 444 | ||||
-rw-r--r-- | kernel/time/timecompare.c | 191 |
5 files changed, 553 insertions, 180 deletions
diff --git a/kernel/time/Makefile b/kernel/time/Makefile index 905b0b50792d..0b0a6366c9d4 100644 --- a/kernel/time/Makefile +++ b/kernel/time/Makefile | |||
@@ -1,4 +1,4 @@ | |||
1 | obj-y += timekeeping.o ntp.o clocksource.o jiffies.o timer_list.o | 1 | obj-y += timekeeping.o ntp.o clocksource.o jiffies.o timer_list.o timecompare.o |
2 | 2 | ||
3 | obj-$(CONFIG_GENERIC_CLOCKEVENTS_BUILD) += clockevents.o | 3 | obj-$(CONFIG_GENERIC_CLOCKEVENTS_BUILD) += clockevents.o |
4 | obj-$(CONFIG_GENERIC_CLOCKEVENTS) += tick-common.o | 4 | obj-$(CONFIG_GENERIC_CLOCKEVENTS) += tick-common.o |
diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c index ea2f48af83cf..d13be216a790 100644 --- a/kernel/time/clockevents.c +++ b/kernel/time/clockevents.c | |||
@@ -68,6 +68,17 @@ void clockevents_set_mode(struct clock_event_device *dev, | |||
68 | if (dev->mode != mode) { | 68 | if (dev->mode != mode) { |
69 | dev->set_mode(mode, dev); | 69 | dev->set_mode(mode, dev); |
70 | dev->mode = mode; | 70 | dev->mode = mode; |
71 | |||
72 | /* | ||
73 | * A nsec2cyc multiplicator of 0 is invalid and we'd crash | ||
74 | * on it, so fix it up and emit a warning: | ||
75 | */ | ||
76 | if (mode == CLOCK_EVT_MODE_ONESHOT) { | ||
77 | if (unlikely(!dev->mult)) { | ||
78 | dev->mult = 1; | ||
79 | WARN_ON(1); | ||
80 | } | ||
81 | } | ||
71 | } | 82 | } |
72 | } | 83 | } |
73 | 84 | ||
@@ -168,15 +179,6 @@ void clockevents_register_device(struct clock_event_device *dev) | |||
168 | BUG_ON(dev->mode != CLOCK_EVT_MODE_UNUSED); | 179 | BUG_ON(dev->mode != CLOCK_EVT_MODE_UNUSED); |
169 | BUG_ON(!dev->cpumask); | 180 | BUG_ON(!dev->cpumask); |
170 | 181 | ||
171 | /* | ||
172 | * A nsec2cyc multiplicator of 0 is invalid and we'd crash | ||
173 | * on it, so fix it up and emit a warning: | ||
174 | */ | ||
175 | if (unlikely(!dev->mult)) { | ||
176 | dev->mult = 1; | ||
177 | WARN_ON(1); | ||
178 | } | ||
179 | |||
180 | spin_lock(&clockevents_lock); | 182 | spin_lock(&clockevents_lock); |
181 | 183 | ||
182 | list_add(&dev->list, &clockevent_devices); | 184 | list_add(&dev->list, &clockevent_devices); |
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index ca89e1593f08..c46c931a7fe7 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c | |||
@@ -31,6 +31,82 @@ | |||
31 | #include <linux/sched.h> /* for spin_unlock_irq() using preempt_count() m68k */ | 31 | #include <linux/sched.h> /* for spin_unlock_irq() using preempt_count() m68k */ |
32 | #include <linux/tick.h> | 32 | #include <linux/tick.h> |
33 | 33 | ||
34 | void timecounter_init(struct timecounter *tc, | ||
35 | const struct cyclecounter *cc, | ||
36 | u64 start_tstamp) | ||
37 | { | ||
38 | tc->cc = cc; | ||
39 | tc->cycle_last = cc->read(cc); | ||
40 | tc->nsec = start_tstamp; | ||
41 | } | ||
42 | EXPORT_SYMBOL(timecounter_init); | ||
43 | |||
44 | /** | ||
45 | * timecounter_read_delta - get nanoseconds since last call of this function | ||
46 | * @tc: Pointer to time counter | ||
47 | * | ||
48 | * When the underlying cycle counter runs over, this will be handled | ||
49 | * correctly as long as it does not run over more than once between | ||
50 | * calls. | ||
51 | * | ||
52 | * The first call to this function for a new time counter initializes | ||
53 | * the time tracking and returns an undefined result. | ||
54 | */ | ||
55 | static u64 timecounter_read_delta(struct timecounter *tc) | ||
56 | { | ||
57 | cycle_t cycle_now, cycle_delta; | ||
58 | u64 ns_offset; | ||
59 | |||
60 | /* read cycle counter: */ | ||
61 | cycle_now = tc->cc->read(tc->cc); | ||
62 | |||
63 | /* calculate the delta since the last timecounter_read_delta(): */ | ||
64 | cycle_delta = (cycle_now - tc->cycle_last) & tc->cc->mask; | ||
65 | |||
66 | /* convert to nanoseconds: */ | ||
67 | ns_offset = cyclecounter_cyc2ns(tc->cc, cycle_delta); | ||
68 | |||
69 | /* update time stamp of timecounter_read_delta() call: */ | ||
70 | tc->cycle_last = cycle_now; | ||
71 | |||
72 | return ns_offset; | ||
73 | } | ||
74 | |||
75 | u64 timecounter_read(struct timecounter *tc) | ||
76 | { | ||
77 | u64 nsec; | ||
78 | |||
79 | /* increment time by nanoseconds since last call */ | ||
80 | nsec = timecounter_read_delta(tc); | ||
81 | nsec += tc->nsec; | ||
82 | tc->nsec = nsec; | ||
83 | |||
84 | return nsec; | ||
85 | } | ||
86 | EXPORT_SYMBOL(timecounter_read); | ||
87 | |||
88 | u64 timecounter_cyc2time(struct timecounter *tc, | ||
89 | cycle_t cycle_tstamp) | ||
90 | { | ||
91 | u64 cycle_delta = (cycle_tstamp - tc->cycle_last) & tc->cc->mask; | ||
92 | u64 nsec; | ||
93 | |||
94 | /* | ||
95 | * Instead of always treating cycle_tstamp as more recent | ||
96 | * than tc->cycle_last, detect when it is too far in the | ||
97 | * future and treat it as old time stamp instead. | ||
98 | */ | ||
99 | if (cycle_delta > tc->cc->mask / 2) { | ||
100 | cycle_delta = (tc->cycle_last - cycle_tstamp) & tc->cc->mask; | ||
101 | nsec = tc->nsec - cyclecounter_cyc2ns(tc->cc, cycle_delta); | ||
102 | } else { | ||
103 | nsec = cyclecounter_cyc2ns(tc->cc, cycle_delta) + tc->nsec; | ||
104 | } | ||
105 | |||
106 | return nsec; | ||
107 | } | ||
108 | EXPORT_SYMBOL(timecounter_cyc2time); | ||
109 | |||
34 | /* XXX - Would like a better way for initializing curr_clocksource */ | 110 | /* XXX - Would like a better way for initializing curr_clocksource */ |
35 | extern struct clocksource clocksource_jiffies; | 111 | extern struct clocksource clocksource_jiffies; |
36 | 112 | ||
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index f5f793d92415..7fc64375ff43 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c | |||
@@ -1,71 +1,129 @@ | |||
1 | /* | 1 | /* |
2 | * linux/kernel/time/ntp.c | ||
3 | * | ||
4 | * NTP state machine interfaces and logic. | 2 | * NTP state machine interfaces and logic. |
5 | * | 3 | * |
6 | * This code was mainly moved from kernel/timer.c and kernel/time.c | 4 | * This code was mainly moved from kernel/timer.c and kernel/time.c |
7 | * Please see those files for relevant copyright info and historical | 5 | * Please see those files for relevant copyright info and historical |
8 | * changelogs. | 6 | * changelogs. |
9 | */ | 7 | */ |
10 | |||
11 | #include <linux/mm.h> | ||
12 | #include <linux/time.h> | ||
13 | #include <linux/timex.h> | ||
14 | #include <linux/jiffies.h> | ||
15 | #include <linux/hrtimer.h> | ||
16 | #include <linux/capability.h> | 8 | #include <linux/capability.h> |
17 | #include <linux/math64.h> | ||
18 | #include <linux/clocksource.h> | 9 | #include <linux/clocksource.h> |
19 | #include <linux/workqueue.h> | 10 | #include <linux/workqueue.h> |
20 | #include <asm/timex.h> | 11 | #include <linux/hrtimer.h> |
12 | #include <linux/jiffies.h> | ||
13 | #include <linux/math64.h> | ||
14 | #include <linux/timex.h> | ||
15 | #include <linux/time.h> | ||
16 | #include <linux/mm.h> | ||
21 | 17 | ||
22 | /* | 18 | /* |
23 | * Timekeeping variables | 19 | * NTP timekeeping variables: |
24 | */ | 20 | */ |
25 | unsigned long tick_usec = TICK_USEC; /* USER_HZ period (usec) */ | ||
26 | unsigned long tick_nsec; /* ACTHZ period (nsec) */ | ||
27 | u64 tick_length; | ||
28 | static u64 tick_length_base; | ||
29 | 21 | ||
30 | static struct hrtimer leap_timer; | 22 | /* USER_HZ period (usecs): */ |
23 | unsigned long tick_usec = TICK_USEC; | ||
31 | 24 | ||
32 | #define MAX_TICKADJ 500 /* microsecs */ | 25 | /* ACTHZ period (nsecs): */ |
33 | #define MAX_TICKADJ_SCALED (((u64)(MAX_TICKADJ * NSEC_PER_USEC) << \ | 26 | unsigned long tick_nsec; |
34 | NTP_SCALE_SHIFT) / NTP_INTERVAL_FREQ) | 27 | |
28 | u64 tick_length; | ||
29 | static u64 tick_length_base; | ||
30 | |||
31 | static struct hrtimer leap_timer; | ||
32 | |||
33 | #define MAX_TICKADJ 500LL /* usecs */ | ||
34 | #define MAX_TICKADJ_SCALED \ | ||
35 | (((MAX_TICKADJ * NSEC_PER_USEC) << NTP_SCALE_SHIFT) / NTP_INTERVAL_FREQ) | ||
35 | 36 | ||
36 | /* | 37 | /* |
37 | * phase-lock loop variables | 38 | * phase-lock loop variables |
38 | */ | 39 | */ |
39 | /* TIME_ERROR prevents overwriting the CMOS clock */ | ||
40 | static int time_state = TIME_OK; /* clock synchronization status */ | ||
41 | int time_status = STA_UNSYNC; /* clock status bits */ | ||
42 | static long time_tai; /* TAI offset (s) */ | ||
43 | static s64 time_offset; /* time adjustment (ns) */ | ||
44 | static long time_constant = 2; /* pll time constant */ | ||
45 | long time_maxerror = NTP_PHASE_LIMIT; /* maximum error (us) */ | ||
46 | long time_esterror = NTP_PHASE_LIMIT; /* estimated error (us) */ | ||
47 | static s64 time_freq; /* frequency offset (scaled ns/s)*/ | ||
48 | static long time_reftime; /* time at last adjustment (s) */ | ||
49 | long time_adjust; | ||
50 | static long ntp_tick_adj; | ||
51 | 40 | ||
41 | /* | ||
42 | * clock synchronization status | ||
43 | * | ||
44 | * (TIME_ERROR prevents overwriting the CMOS clock) | ||
45 | */ | ||
46 | static int time_state = TIME_OK; | ||
47 | |||
48 | /* clock status bits: */ | ||
49 | int time_status = STA_UNSYNC; | ||
50 | |||
51 | /* TAI offset (secs): */ | ||
52 | static long time_tai; | ||
53 | |||
54 | /* time adjustment (nsecs): */ | ||
55 | static s64 time_offset; | ||
56 | |||
57 | /* pll time constant: */ | ||
58 | static long time_constant = 2; | ||
59 | |||
60 | /* maximum error (usecs): */ | ||
61 | long time_maxerror = NTP_PHASE_LIMIT; | ||
62 | |||
63 | /* estimated error (usecs): */ | ||
64 | long time_esterror = NTP_PHASE_LIMIT; | ||
65 | |||
66 | /* frequency offset (scaled nsecs/secs): */ | ||
67 | static s64 time_freq; | ||
68 | |||
69 | /* time at last adjustment (secs): */ | ||
70 | static long time_reftime; | ||
71 | |||
72 | long time_adjust; | ||
73 | |||
74 | /* constant (boot-param configurable) NTP tick adjustment (upscaled) */ | ||
75 | static s64 ntp_tick_adj; | ||
76 | |||
77 | /* | ||
78 | * NTP methods: | ||
79 | */ | ||
80 | |||
81 | /* | ||
82 | * Update (tick_length, tick_length_base, tick_nsec), based | ||
83 | * on (tick_usec, ntp_tick_adj, time_freq): | ||
84 | */ | ||
52 | static void ntp_update_frequency(void) | 85 | static void ntp_update_frequency(void) |
53 | { | 86 | { |
54 | u64 second_length = (u64)(tick_usec * NSEC_PER_USEC * USER_HZ) | 87 | u64 second_length; |
55 | << NTP_SCALE_SHIFT; | 88 | u64 new_base; |
56 | second_length += (s64)ntp_tick_adj << NTP_SCALE_SHIFT; | 89 | |
57 | second_length += time_freq; | 90 | second_length = (u64)(tick_usec * NSEC_PER_USEC * USER_HZ) |
91 | << NTP_SCALE_SHIFT; | ||
92 | |||
93 | second_length += ntp_tick_adj; | ||
94 | second_length += time_freq; | ||
58 | 95 | ||
59 | tick_length_base = second_length; | 96 | tick_nsec = div_u64(second_length, HZ) >> NTP_SCALE_SHIFT; |
97 | new_base = div_u64(second_length, NTP_INTERVAL_FREQ); | ||
60 | 98 | ||
61 | tick_nsec = div_u64(second_length, HZ) >> NTP_SCALE_SHIFT; | 99 | /* |
62 | tick_length_base = div_u64(tick_length_base, NTP_INTERVAL_FREQ); | 100 | * Don't wait for the next second_overflow, apply |
101 | * the change to the tick length immediately: | ||
102 | */ | ||
103 | tick_length += new_base - tick_length_base; | ||
104 | tick_length_base = new_base; | ||
105 | } | ||
106 | |||
107 | static inline s64 ntp_update_offset_fll(s64 offset64, long secs) | ||
108 | { | ||
109 | time_status &= ~STA_MODE; | ||
110 | |||
111 | if (secs < MINSEC) | ||
112 | return 0; | ||
113 | |||
114 | if (!(time_status & STA_FLL) && (secs <= MAXSEC)) | ||
115 | return 0; | ||
116 | |||
117 | time_status |= STA_MODE; | ||
118 | |||
119 | return div_s64(offset64 << (NTP_SCALE_SHIFT - SHIFT_FLL), secs); | ||
63 | } | 120 | } |
64 | 121 | ||
65 | static void ntp_update_offset(long offset) | 122 | static void ntp_update_offset(long offset) |
66 | { | 123 | { |
67 | long mtemp; | ||
68 | s64 freq_adj; | 124 | s64 freq_adj; |
125 | s64 offset64; | ||
126 | long secs; | ||
69 | 127 | ||
70 | if (!(time_status & STA_PLL)) | 128 | if (!(time_status & STA_PLL)) |
71 | return; | 129 | return; |
@@ -84,24 +142,23 @@ static void ntp_update_offset(long offset) | |||
84 | * Select how the frequency is to be controlled | 142 | * Select how the frequency is to be controlled |
85 | * and in which mode (PLL or FLL). | 143 | * and in which mode (PLL or FLL). |
86 | */ | 144 | */ |
87 | if (time_status & STA_FREQHOLD || time_reftime == 0) | 145 | secs = xtime.tv_sec - time_reftime; |
88 | time_reftime = xtime.tv_sec; | 146 | if (unlikely(time_status & STA_FREQHOLD)) |
89 | mtemp = xtime.tv_sec - time_reftime; | 147 | secs = 0; |
148 | |||
90 | time_reftime = xtime.tv_sec; | 149 | time_reftime = xtime.tv_sec; |
91 | 150 | ||
92 | freq_adj = (s64)offset * mtemp; | 151 | offset64 = offset; |
93 | freq_adj <<= NTP_SCALE_SHIFT - 2 * (SHIFT_PLL + 2 + time_constant); | 152 | freq_adj = (offset64 * secs) << |
94 | time_status &= ~STA_MODE; | 153 | (NTP_SCALE_SHIFT - 2 * (SHIFT_PLL + 2 + time_constant)); |
95 | if (mtemp >= MINSEC && (time_status & STA_FLL || mtemp > MAXSEC)) { | ||
96 | freq_adj += div_s64((s64)offset << (NTP_SCALE_SHIFT - SHIFT_FLL), | ||
97 | mtemp); | ||
98 | time_status |= STA_MODE; | ||
99 | } | ||
100 | freq_adj += time_freq; | ||
101 | freq_adj = min(freq_adj, MAXFREQ_SCALED); | ||
102 | time_freq = max(freq_adj, -MAXFREQ_SCALED); | ||
103 | 154 | ||
104 | time_offset = div_s64((s64)offset << NTP_SCALE_SHIFT, NTP_INTERVAL_FREQ); | 155 | freq_adj += ntp_update_offset_fll(offset64, secs); |
156 | |||
157 | freq_adj = min(freq_adj + time_freq, MAXFREQ_SCALED); | ||
158 | |||
159 | time_freq = max(freq_adj, -MAXFREQ_SCALED); | ||
160 | |||
161 | time_offset = div_s64(offset64 << NTP_SCALE_SHIFT, NTP_INTERVAL_FREQ); | ||
105 | } | 162 | } |
106 | 163 | ||
107 | /** | 164 | /** |
@@ -111,15 +168,15 @@ static void ntp_update_offset(long offset) | |||
111 | */ | 168 | */ |
112 | void ntp_clear(void) | 169 | void ntp_clear(void) |
113 | { | 170 | { |
114 | time_adjust = 0; /* stop active adjtime() */ | 171 | time_adjust = 0; /* stop active adjtime() */ |
115 | time_status |= STA_UNSYNC; | 172 | time_status |= STA_UNSYNC; |
116 | time_maxerror = NTP_PHASE_LIMIT; | 173 | time_maxerror = NTP_PHASE_LIMIT; |
117 | time_esterror = NTP_PHASE_LIMIT; | 174 | time_esterror = NTP_PHASE_LIMIT; |
118 | 175 | ||
119 | ntp_update_frequency(); | 176 | ntp_update_frequency(); |
120 | 177 | ||
121 | tick_length = tick_length_base; | 178 | tick_length = tick_length_base; |
122 | time_offset = 0; | 179 | time_offset = 0; |
123 | } | 180 | } |
124 | 181 | ||
125 | /* | 182 | /* |
@@ -140,8 +197,8 @@ static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer) | |||
140 | xtime.tv_sec--; | 197 | xtime.tv_sec--; |
141 | wall_to_monotonic.tv_sec++; | 198 | wall_to_monotonic.tv_sec++; |
142 | time_state = TIME_OOP; | 199 | time_state = TIME_OOP; |
143 | printk(KERN_NOTICE "Clock: " | 200 | printk(KERN_NOTICE |
144 | "inserting leap second 23:59:60 UTC\n"); | 201 | "Clock: inserting leap second 23:59:60 UTC\n"); |
145 | hrtimer_add_expires_ns(&leap_timer, NSEC_PER_SEC); | 202 | hrtimer_add_expires_ns(&leap_timer, NSEC_PER_SEC); |
146 | res = HRTIMER_RESTART; | 203 | res = HRTIMER_RESTART; |
147 | break; | 204 | break; |
@@ -150,8 +207,8 @@ static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer) | |||
150 | time_tai--; | 207 | time_tai--; |
151 | wall_to_monotonic.tv_sec--; | 208 | wall_to_monotonic.tv_sec--; |
152 | time_state = TIME_WAIT; | 209 | time_state = TIME_WAIT; |
153 | printk(KERN_NOTICE "Clock: " | 210 | printk(KERN_NOTICE |
154 | "deleting leap second 23:59:59 UTC\n"); | 211 | "Clock: deleting leap second 23:59:59 UTC\n"); |
155 | break; | 212 | break; |
156 | case TIME_OOP: | 213 | case TIME_OOP: |
157 | time_tai++; | 214 | time_tai++; |
@@ -179,7 +236,7 @@ static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer) | |||
179 | */ | 236 | */ |
180 | void second_overflow(void) | 237 | void second_overflow(void) |
181 | { | 238 | { |
182 | s64 time_adj; | 239 | s64 delta; |
183 | 240 | ||
184 | /* Bump the maxerror field */ | 241 | /* Bump the maxerror field */ |
185 | time_maxerror += MAXFREQ / NSEC_PER_USEC; | 242 | time_maxerror += MAXFREQ / NSEC_PER_USEC; |
@@ -192,24 +249,30 @@ void second_overflow(void) | |||
192 | * Compute the phase adjustment for the next second. The offset is | 249 | * Compute the phase adjustment for the next second. The offset is |
193 | * reduced by a fixed factor times the time constant. | 250 | * reduced by a fixed factor times the time constant. |
194 | */ | 251 | */ |
195 | tick_length = tick_length_base; | 252 | tick_length = tick_length_base; |
196 | time_adj = shift_right(time_offset, SHIFT_PLL + time_constant); | 253 | |
197 | time_offset -= time_adj; | 254 | delta = shift_right(time_offset, SHIFT_PLL + time_constant); |
198 | tick_length += time_adj; | 255 | time_offset -= delta; |
199 | 256 | tick_length += delta; | |
200 | if (unlikely(time_adjust)) { | 257 | |
201 | if (time_adjust > MAX_TICKADJ) { | 258 | if (!time_adjust) |
202 | time_adjust -= MAX_TICKADJ; | 259 | return; |
203 | tick_length += MAX_TICKADJ_SCALED; | 260 | |
204 | } else if (time_adjust < -MAX_TICKADJ) { | 261 | if (time_adjust > MAX_TICKADJ) { |
205 | time_adjust += MAX_TICKADJ; | 262 | time_adjust -= MAX_TICKADJ; |
206 | tick_length -= MAX_TICKADJ_SCALED; | 263 | tick_length += MAX_TICKADJ_SCALED; |
207 | } else { | 264 | return; |
208 | tick_length += (s64)(time_adjust * NSEC_PER_USEC / | ||
209 | NTP_INTERVAL_FREQ) << NTP_SCALE_SHIFT; | ||
210 | time_adjust = 0; | ||
211 | } | ||
212 | } | 265 | } |
266 | |||
267 | if (time_adjust < -MAX_TICKADJ) { | ||
268 | time_adjust += MAX_TICKADJ; | ||
269 | tick_length -= MAX_TICKADJ_SCALED; | ||
270 | return; | ||
271 | } | ||
272 | |||
273 | tick_length += (s64)(time_adjust * NSEC_PER_USEC / NTP_INTERVAL_FREQ) | ||
274 | << NTP_SCALE_SHIFT; | ||
275 | time_adjust = 0; | ||
213 | } | 276 | } |
214 | 277 | ||
215 | #ifdef CONFIG_GENERIC_CMOS_UPDATE | 278 | #ifdef CONFIG_GENERIC_CMOS_UPDATE |
@@ -233,12 +296,13 @@ static void sync_cmos_clock(struct work_struct *work) | |||
233 | * This code is run on a timer. If the clock is set, that timer | 296 | * This code is run on a timer. If the clock is set, that timer |
234 | * may not expire at the correct time. Thus, we adjust... | 297 | * may not expire at the correct time. Thus, we adjust... |
235 | */ | 298 | */ |
236 | if (!ntp_synced()) | 299 | if (!ntp_synced()) { |
237 | /* | 300 | /* |
238 | * Not synced, exit, do not restart a timer (if one is | 301 | * Not synced, exit, do not restart a timer (if one is |
239 | * running, let it run out). | 302 | * running, let it run out). |
240 | */ | 303 | */ |
241 | return; | 304 | return; |
305 | } | ||
242 | 306 | ||
243 | getnstimeofday(&now); | 307 | getnstimeofday(&now); |
244 | if (abs(now.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec / 2) | 308 | if (abs(now.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec / 2) |
@@ -270,7 +334,116 @@ static void notify_cmos_timer(void) | |||
270 | static inline void notify_cmos_timer(void) { } | 334 | static inline void notify_cmos_timer(void) { } |
271 | #endif | 335 | #endif |
272 | 336 | ||
273 | /* adjtimex mainly allows reading (and writing, if superuser) of | 337 | /* |
338 | * Start the leap seconds timer: | ||
339 | */ | ||
340 | static inline void ntp_start_leap_timer(struct timespec *ts) | ||
341 | { | ||
342 | long now = ts->tv_sec; | ||
343 | |||
344 | if (time_status & STA_INS) { | ||
345 | time_state = TIME_INS; | ||
346 | now += 86400 - now % 86400; | ||
347 | hrtimer_start(&leap_timer, ktime_set(now, 0), HRTIMER_MODE_ABS); | ||
348 | |||
349 | return; | ||
350 | } | ||
351 | |||
352 | if (time_status & STA_DEL) { | ||
353 | time_state = TIME_DEL; | ||
354 | now += 86400 - (now + 1) % 86400; | ||
355 | hrtimer_start(&leap_timer, ktime_set(now, 0), HRTIMER_MODE_ABS); | ||
356 | } | ||
357 | } | ||
358 | |||
359 | /* | ||
360 | * Propagate a new txc->status value into the NTP state: | ||
361 | */ | ||
362 | static inline void process_adj_status(struct timex *txc, struct timespec *ts) | ||
363 | { | ||
364 | if ((time_status & STA_PLL) && !(txc->status & STA_PLL)) { | ||
365 | time_state = TIME_OK; | ||
366 | time_status = STA_UNSYNC; | ||
367 | } | ||
368 | |||
369 | /* | ||
370 | * If we turn on PLL adjustments then reset the | ||
371 | * reference time to current time. | ||
372 | */ | ||
373 | if (!(time_status & STA_PLL) && (txc->status & STA_PLL)) | ||
374 | time_reftime = xtime.tv_sec; | ||
375 | |||
376 | /* only set allowed bits */ | ||
377 | time_status &= STA_RONLY; | ||
378 | time_status |= txc->status & ~STA_RONLY; | ||
379 | |||
380 | switch (time_state) { | ||
381 | case TIME_OK: | ||
382 | ntp_start_leap_timer(ts); | ||
383 | break; | ||
384 | case TIME_INS: | ||
385 | case TIME_DEL: | ||
386 | time_state = TIME_OK; | ||
387 | ntp_start_leap_timer(ts); | ||
388 | case TIME_WAIT: | ||
389 | if (!(time_status & (STA_INS | STA_DEL))) | ||
390 | time_state = TIME_OK; | ||
391 | break; | ||
392 | case TIME_OOP: | ||
393 | hrtimer_restart(&leap_timer); | ||
394 | break; | ||
395 | } | ||
396 | } | ||
397 | /* | ||
398 | * Called with the xtime lock held, so we can access and modify | ||
399 | * all the global NTP state: | ||
400 | */ | ||
401 | static inline void process_adjtimex_modes(struct timex *txc, struct timespec *ts) | ||
402 | { | ||
403 | if (txc->modes & ADJ_STATUS) | ||
404 | process_adj_status(txc, ts); | ||
405 | |||
406 | if (txc->modes & ADJ_NANO) | ||
407 | time_status |= STA_NANO; | ||
408 | |||
409 | if (txc->modes & ADJ_MICRO) | ||
410 | time_status &= ~STA_NANO; | ||
411 | |||
412 | if (txc->modes & ADJ_FREQUENCY) { | ||
413 | time_freq = txc->freq * PPM_SCALE; | ||
414 | time_freq = min(time_freq, MAXFREQ_SCALED); | ||
415 | time_freq = max(time_freq, -MAXFREQ_SCALED); | ||
416 | } | ||
417 | |||
418 | if (txc->modes & ADJ_MAXERROR) | ||
419 | time_maxerror = txc->maxerror; | ||
420 | |||
421 | if (txc->modes & ADJ_ESTERROR) | ||
422 | time_esterror = txc->esterror; | ||
423 | |||
424 | if (txc->modes & ADJ_TIMECONST) { | ||
425 | time_constant = txc->constant; | ||
426 | if (!(time_status & STA_NANO)) | ||
427 | time_constant += 4; | ||
428 | time_constant = min(time_constant, (long)MAXTC); | ||
429 | time_constant = max(time_constant, 0l); | ||
430 | } | ||
431 | |||
432 | if (txc->modes & ADJ_TAI && txc->constant > 0) | ||
433 | time_tai = txc->constant; | ||
434 | |||
435 | if (txc->modes & ADJ_OFFSET) | ||
436 | ntp_update_offset(txc->offset); | ||
437 | |||
438 | if (txc->modes & ADJ_TICK) | ||
439 | tick_usec = txc->tick; | ||
440 | |||
441 | if (txc->modes & (ADJ_TICK|ADJ_FREQUENCY|ADJ_OFFSET)) | ||
442 | ntp_update_frequency(); | ||
443 | } | ||
444 | |||
445 | /* | ||
446 | * adjtimex mainly allows reading (and writing, if superuser) of | ||
274 | * kernel time-keeping variables. used by xntpd. | 447 | * kernel time-keeping variables. used by xntpd. |
275 | */ | 448 | */ |
276 | int do_adjtimex(struct timex *txc) | 449 | int do_adjtimex(struct timex *txc) |
@@ -291,11 +464,14 @@ int do_adjtimex(struct timex *txc) | |||
291 | if (txc->modes && !capable(CAP_SYS_TIME)) | 464 | if (txc->modes && !capable(CAP_SYS_TIME)) |
292 | return -EPERM; | 465 | return -EPERM; |
293 | 466 | ||
294 | /* if the quartz is off by more than 10% something is VERY wrong! */ | 467 | /* |
468 | * if the quartz is off by more than 10% then | ||
469 | * something is VERY wrong! | ||
470 | */ | ||
295 | if (txc->modes & ADJ_TICK && | 471 | if (txc->modes & ADJ_TICK && |
296 | (txc->tick < 900000/USER_HZ || | 472 | (txc->tick < 900000/USER_HZ || |
297 | txc->tick > 1100000/USER_HZ)) | 473 | txc->tick > 1100000/USER_HZ)) |
298 | return -EINVAL; | 474 | return -EINVAL; |
299 | 475 | ||
300 | if (txc->modes & ADJ_STATUS && time_state != TIME_OK) | 476 | if (txc->modes & ADJ_STATUS && time_state != TIME_OK) |
301 | hrtimer_cancel(&leap_timer); | 477 | hrtimer_cancel(&leap_timer); |
@@ -305,7 +481,6 @@ int do_adjtimex(struct timex *txc) | |||
305 | 481 | ||
306 | write_seqlock_irq(&xtime_lock); | 482 | write_seqlock_irq(&xtime_lock); |
307 | 483 | ||
308 | /* If there are input parameters, then process them */ | ||
309 | if (txc->modes & ADJ_ADJTIME) { | 484 | if (txc->modes & ADJ_ADJTIME) { |
310 | long save_adjust = time_adjust; | 485 | long save_adjust = time_adjust; |
311 | 486 | ||
@@ -315,98 +490,24 @@ int do_adjtimex(struct timex *txc) | |||
315 | ntp_update_frequency(); | 490 | ntp_update_frequency(); |
316 | } | 491 | } |
317 | txc->offset = save_adjust; | 492 | txc->offset = save_adjust; |
318 | goto adj_done; | 493 | } else { |
319 | } | ||
320 | if (txc->modes) { | ||
321 | long sec; | ||
322 | |||
323 | if (txc->modes & ADJ_STATUS) { | ||
324 | if ((time_status & STA_PLL) && | ||
325 | !(txc->status & STA_PLL)) { | ||
326 | time_state = TIME_OK; | ||
327 | time_status = STA_UNSYNC; | ||
328 | } | ||
329 | /* only set allowed bits */ | ||
330 | time_status &= STA_RONLY; | ||
331 | time_status |= txc->status & ~STA_RONLY; | ||
332 | |||
333 | switch (time_state) { | ||
334 | case TIME_OK: | ||
335 | start_timer: | ||
336 | sec = ts.tv_sec; | ||
337 | if (time_status & STA_INS) { | ||
338 | time_state = TIME_INS; | ||
339 | sec += 86400 - sec % 86400; | ||
340 | hrtimer_start(&leap_timer, ktime_set(sec, 0), HRTIMER_MODE_ABS); | ||
341 | } else if (time_status & STA_DEL) { | ||
342 | time_state = TIME_DEL; | ||
343 | sec += 86400 - (sec + 1) % 86400; | ||
344 | hrtimer_start(&leap_timer, ktime_set(sec, 0), HRTIMER_MODE_ABS); | ||
345 | } | ||
346 | break; | ||
347 | case TIME_INS: | ||
348 | case TIME_DEL: | ||
349 | time_state = TIME_OK; | ||
350 | goto start_timer; | ||
351 | break; | ||
352 | case TIME_WAIT: | ||
353 | if (!(time_status & (STA_INS | STA_DEL))) | ||
354 | time_state = TIME_OK; | ||
355 | break; | ||
356 | case TIME_OOP: | ||
357 | hrtimer_restart(&leap_timer); | ||
358 | break; | ||
359 | } | ||
360 | } | ||
361 | |||
362 | if (txc->modes & ADJ_NANO) | ||
363 | time_status |= STA_NANO; | ||
364 | if (txc->modes & ADJ_MICRO) | ||
365 | time_status &= ~STA_NANO; | ||
366 | |||
367 | if (txc->modes & ADJ_FREQUENCY) { | ||
368 | time_freq = (s64)txc->freq * PPM_SCALE; | ||
369 | time_freq = min(time_freq, MAXFREQ_SCALED); | ||
370 | time_freq = max(time_freq, -MAXFREQ_SCALED); | ||
371 | } | ||
372 | |||
373 | if (txc->modes & ADJ_MAXERROR) | ||
374 | time_maxerror = txc->maxerror; | ||
375 | if (txc->modes & ADJ_ESTERROR) | ||
376 | time_esterror = txc->esterror; | ||
377 | |||
378 | if (txc->modes & ADJ_TIMECONST) { | ||
379 | time_constant = txc->constant; | ||
380 | if (!(time_status & STA_NANO)) | ||
381 | time_constant += 4; | ||
382 | time_constant = min(time_constant, (long)MAXTC); | ||
383 | time_constant = max(time_constant, 0l); | ||
384 | } | ||
385 | |||
386 | if (txc->modes & ADJ_TAI && txc->constant > 0) | ||
387 | time_tai = txc->constant; | ||
388 | |||
389 | if (txc->modes & ADJ_OFFSET) | ||
390 | ntp_update_offset(txc->offset); | ||
391 | if (txc->modes & ADJ_TICK) | ||
392 | tick_usec = txc->tick; | ||
393 | 494 | ||
394 | if (txc->modes & (ADJ_TICK|ADJ_FREQUENCY|ADJ_OFFSET)) | 495 | /* If there are input parameters, then process them: */ |
395 | ntp_update_frequency(); | 496 | if (txc->modes) |
396 | } | 497 | process_adjtimex_modes(txc, &ts); |
397 | 498 | ||
398 | txc->offset = shift_right(time_offset * NTP_INTERVAL_FREQ, | 499 | txc->offset = shift_right(time_offset * NTP_INTERVAL_FREQ, |
399 | NTP_SCALE_SHIFT); | 500 | NTP_SCALE_SHIFT); |
400 | if (!(time_status & STA_NANO)) | 501 | if (!(time_status & STA_NANO)) |
401 | txc->offset /= NSEC_PER_USEC; | 502 | txc->offset /= NSEC_PER_USEC; |
503 | } | ||
402 | 504 | ||
403 | adj_done: | ||
404 | result = time_state; /* mostly `TIME_OK' */ | 505 | result = time_state; /* mostly `TIME_OK' */ |
405 | if (time_status & (STA_UNSYNC|STA_CLOCKERR)) | 506 | if (time_status & (STA_UNSYNC|STA_CLOCKERR)) |
406 | result = TIME_ERROR; | 507 | result = TIME_ERROR; |
407 | 508 | ||
408 | txc->freq = shift_right((time_freq >> PPM_SCALE_INV_SHIFT) * | 509 | txc->freq = shift_right((time_freq >> PPM_SCALE_INV_SHIFT) * |
409 | (s64)PPM_SCALE_INV, NTP_SCALE_SHIFT); | 510 | PPM_SCALE_INV, NTP_SCALE_SHIFT); |
410 | txc->maxerror = time_maxerror; | 511 | txc->maxerror = time_maxerror; |
411 | txc->esterror = time_esterror; | 512 | txc->esterror = time_esterror; |
412 | txc->status = time_status; | 513 | txc->status = time_status; |
@@ -425,6 +526,7 @@ adj_done: | |||
425 | txc->calcnt = 0; | 526 | txc->calcnt = 0; |
426 | txc->errcnt = 0; | 527 | txc->errcnt = 0; |
427 | txc->stbcnt = 0; | 528 | txc->stbcnt = 0; |
529 | |||
428 | write_sequnlock_irq(&xtime_lock); | 530 | write_sequnlock_irq(&xtime_lock); |
429 | 531 | ||
430 | txc->time.tv_sec = ts.tv_sec; | 532 | txc->time.tv_sec = ts.tv_sec; |
@@ -440,6 +542,8 @@ adj_done: | |||
440 | static int __init ntp_tick_adj_setup(char *str) | 542 | static int __init ntp_tick_adj_setup(char *str) |
441 | { | 543 | { |
442 | ntp_tick_adj = simple_strtol(str, NULL, 0); | 544 | ntp_tick_adj = simple_strtol(str, NULL, 0); |
545 | ntp_tick_adj <<= NTP_SCALE_SHIFT; | ||
546 | |||
443 | return 1; | 547 | return 1; |
444 | } | 548 | } |
445 | 549 | ||
diff --git a/kernel/time/timecompare.c b/kernel/time/timecompare.c new file mode 100644 index 000000000000..71e7f1a19156 --- /dev/null +++ b/kernel/time/timecompare.c | |||
@@ -0,0 +1,191 @@ | |||
1 | /* | ||
2 | * Copyright (C) 2009 Intel Corporation. | ||
3 | * Author: Patrick Ohly <patrick.ohly@intel.com> | ||
4 | * | ||
5 | * This program is free software; you can redistribute it and/or modify | ||
6 | * it under the terms of the GNU General Public License as published by | ||
7 | * the Free Software Foundation; either version 2 of the License, or | ||
8 | * (at your option) any later version. | ||
9 | * | ||
10 | * This program is distributed in the hope that it will be useful, | ||
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
13 | * GNU General Public License for more details. | ||
14 | * | ||
15 | * You should have received a copy of the GNU General Public License | ||
16 | * along with this program; if not, write to the Free Software | ||
17 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | ||
18 | */ | ||
19 | |||
20 | #include <linux/timecompare.h> | ||
21 | #include <linux/module.h> | ||
22 | #include <linux/math64.h> | ||
23 | |||
24 | /* | ||
25 | * fixed point arithmetic scale factor for skew | ||
26 | * | ||
27 | * Usually one would measure skew in ppb (parts per billion, 1e9), but | ||
28 | * using a factor of 2 simplifies the math. | ||
29 | */ | ||
30 | #define TIMECOMPARE_SKEW_RESOLUTION (((s64)1)<<30) | ||
31 | |||
32 | ktime_t timecompare_transform(struct timecompare *sync, | ||
33 | u64 source_tstamp) | ||
34 | { | ||
35 | u64 nsec; | ||
36 | |||
37 | nsec = source_tstamp + sync->offset; | ||
38 | nsec += (s64)(source_tstamp - sync->last_update) * sync->skew / | ||
39 | TIMECOMPARE_SKEW_RESOLUTION; | ||
40 | |||
41 | return ns_to_ktime(nsec); | ||
42 | } | ||
43 | EXPORT_SYMBOL(timecompare_transform); | ||
44 | |||
45 | int timecompare_offset(struct timecompare *sync, | ||
46 | s64 *offset, | ||
47 | u64 *source_tstamp) | ||
48 | { | ||
49 | u64 start_source = 0, end_source = 0; | ||
50 | struct { | ||
51 | s64 offset; | ||
52 | s64 duration_target; | ||
53 | } buffer[10], sample, *samples; | ||
54 | int counter = 0, i; | ||
55 | int used; | ||
56 | int index; | ||
57 | int num_samples = sync->num_samples; | ||
58 | |||
59 | if (num_samples > sizeof(buffer)/sizeof(buffer[0])) { | ||
60 | samples = kmalloc(sizeof(*samples) * num_samples, GFP_ATOMIC); | ||
61 | if (!samples) { | ||
62 | samples = buffer; | ||
63 | num_samples = sizeof(buffer)/sizeof(buffer[0]); | ||
64 | } | ||
65 | } else { | ||
66 | samples = buffer; | ||
67 | } | ||
68 | |||
69 | /* run until we have enough valid samples, but do not try forever */ | ||
70 | i = 0; | ||
71 | counter = 0; | ||
72 | while (1) { | ||
73 | u64 ts; | ||
74 | ktime_t start, end; | ||
75 | |||
76 | start = sync->target(); | ||
77 | ts = timecounter_read(sync->source); | ||
78 | end = sync->target(); | ||
79 | |||
80 | if (!i) | ||
81 | start_source = ts; | ||
82 | |||
83 | /* ignore negative durations */ | ||
84 | sample.duration_target = ktime_to_ns(ktime_sub(end, start)); | ||
85 | if (sample.duration_target >= 0) { | ||
86 | /* | ||
87 | * assume symetric delay to and from source: | ||
88 | * average target time corresponds to measured | ||
89 | * source time | ||
90 | */ | ||
91 | sample.offset = | ||
92 | ktime_to_ns(ktime_add(end, start)) / 2 - | ||
93 | ts; | ||
94 | |||
95 | /* simple insertion sort based on duration */ | ||
96 | index = counter - 1; | ||
97 | while (index >= 0) { | ||
98 | if (samples[index].duration_target < | ||
99 | sample.duration_target) | ||
100 | break; | ||
101 | samples[index + 1] = samples[index]; | ||
102 | index--; | ||
103 | } | ||
104 | samples[index + 1] = sample; | ||
105 | counter++; | ||
106 | } | ||
107 | |||
108 | i++; | ||
109 | if (counter >= num_samples || i >= 100000) { | ||
110 | end_source = ts; | ||
111 | break; | ||
112 | } | ||
113 | } | ||
114 | |||
115 | *source_tstamp = (end_source + start_source) / 2; | ||
116 | |||
117 | /* remove outliers by only using 75% of the samples */ | ||
118 | used = counter * 3 / 4; | ||
119 | if (!used) | ||
120 | used = counter; | ||
121 | if (used) { | ||
122 | /* calculate average */ | ||
123 | s64 off = 0; | ||
124 | for (index = 0; index < used; index++) | ||
125 | off += samples[index].offset; | ||
126 | *offset = div_s64(off, used); | ||
127 | } | ||
128 | |||
129 | if (samples && samples != buffer) | ||
130 | kfree(samples); | ||
131 | |||
132 | return used; | ||
133 | } | ||
134 | EXPORT_SYMBOL(timecompare_offset); | ||
135 | |||
136 | void __timecompare_update(struct timecompare *sync, | ||
137 | u64 source_tstamp) | ||
138 | { | ||
139 | s64 offset; | ||
140 | u64 average_time; | ||
141 | |||
142 | if (!timecompare_offset(sync, &offset, &average_time)) | ||
143 | return; | ||
144 | |||
145 | if (!sync->last_update) { | ||
146 | sync->last_update = average_time; | ||
147 | sync->offset = offset; | ||
148 | sync->skew = 0; | ||
149 | } else { | ||
150 | s64 delta_nsec = average_time - sync->last_update; | ||
151 | |||
152 | /* avoid division by negative or small deltas */ | ||
153 | if (delta_nsec >= 10000) { | ||
154 | s64 delta_offset_nsec = offset - sync->offset; | ||
155 | s64 skew; /* delta_offset_nsec * | ||
156 | TIMECOMPARE_SKEW_RESOLUTION / | ||
157 | delta_nsec */ | ||
158 | u64 divisor; | ||
159 | |||
160 | /* div_s64() is limited to 32 bit divisor */ | ||
161 | skew = delta_offset_nsec * TIMECOMPARE_SKEW_RESOLUTION; | ||
162 | divisor = delta_nsec; | ||
163 | while (unlikely(divisor >= ((s64)1) << 32)) { | ||
164 | /* divide both by 2; beware, right shift | ||
165 | of negative value has undefined | ||
166 | behavior and can only be used for | ||
167 | the positive divisor */ | ||
168 | skew = div_s64(skew, 2); | ||
169 | divisor >>= 1; | ||
170 | } | ||
171 | skew = div_s64(skew, divisor); | ||
172 | |||
173 | /* | ||
174 | * Calculate new overall skew as 4/16 the | ||
175 | * old value and 12/16 the new one. This is | ||
176 | * a rather arbitrary tradeoff between | ||
177 | * only using the latest measurement (0/16 and | ||
178 | * 16/16) and even more weight on past measurements. | ||
179 | */ | ||
180 | #define TIMECOMPARE_NEW_SKEW_PER_16 12 | ||
181 | sync->skew = | ||
182 | div_s64((16 - TIMECOMPARE_NEW_SKEW_PER_16) * | ||
183 | sync->skew + | ||
184 | TIMECOMPARE_NEW_SKEW_PER_16 * skew, | ||
185 | 16); | ||
186 | sync->last_update = average_time; | ||
187 | sync->offset = offset; | ||
188 | } | ||
189 | } | ||
190 | } | ||
191 | EXPORT_SYMBOL(__timecompare_update); | ||