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-rw-r--r--arch/i386/kernel/timers/timer_tsc.c178
1 files changed, 0 insertions, 178 deletions
diff --git a/arch/i386/kernel/timers/timer_tsc.c b/arch/i386/kernel/timers/timer_tsc.c
index f1187ddb0d0f..243ec0484079 100644
--- a/arch/i386/kernel/timers/timer_tsc.c
+++ b/arch/i386/kernel/timers/timer_tsc.c
@@ -32,10 +32,6 @@ static unsigned long hpet_last;
32static struct timer_opts timer_tsc; 32static struct timer_opts timer_tsc;
33#endif 33#endif
34 34
35static inline void cpufreq_delayed_get(void);
36
37int tsc_disable __devinitdata = 0;
38
39static int use_tsc; 35static int use_tsc;
40/* Number of usecs that the last interrupt was delayed */ 36/* Number of usecs that the last interrupt was delayed */
41static int delay_at_last_interrupt; 37static int delay_at_last_interrupt;
@@ -144,30 +140,6 @@ static unsigned long long monotonic_clock_tsc(void)
144 return base + cycles_2_ns(this_offset - last_offset); 140 return base + cycles_2_ns(this_offset - last_offset);
145} 141}
146 142
147/*
148 * Scheduler clock - returns current time in nanosec units.
149 */
150unsigned long long sched_clock(void)
151{
152 unsigned long long this_offset;
153
154 /*
155 * In the NUMA case we dont use the TSC as they are not
156 * synchronized across all CPUs.
157 */
158#ifndef CONFIG_NUMA
159 if (!use_tsc)
160#endif
161 /* no locking but a rare wrong value is not a big deal */
162 return jiffies_64 * (1000000000 / HZ);
163
164 /* Read the Time Stamp Counter */
165 rdtscll(this_offset);
166
167 /* return the value in ns */
168 return cycles_2_ns(this_offset);
169}
170
171static void delay_tsc(unsigned long loops) 143static void delay_tsc(unsigned long loops)
172{ 144{
173 unsigned long bclock, now; 145 unsigned long bclock, now;
@@ -231,136 +203,6 @@ static void mark_offset_tsc_hpet(void)
231} 203}
232#endif 204#endif
233 205
234
235#ifdef CONFIG_CPU_FREQ
236#include <linux/workqueue.h>
237
238static unsigned int cpufreq_delayed_issched = 0;
239static unsigned int cpufreq_init = 0;
240static struct work_struct cpufreq_delayed_get_work;
241
242static void handle_cpufreq_delayed_get(void *v)
243{
244 unsigned int cpu;
245 for_each_online_cpu(cpu) {
246 cpufreq_get(cpu);
247 }
248 cpufreq_delayed_issched = 0;
249}
250
251/* if we notice lost ticks, schedule a call to cpufreq_get() as it tries
252 * to verify the CPU frequency the timing core thinks the CPU is running
253 * at is still correct.
254 */
255static inline void cpufreq_delayed_get(void)
256{
257 if (cpufreq_init && !cpufreq_delayed_issched) {
258 cpufreq_delayed_issched = 1;
259 printk(KERN_DEBUG "Losing some ticks... checking if CPU frequency changed.\n");
260 schedule_work(&cpufreq_delayed_get_work);
261 }
262}
263
264/* If the CPU frequency is scaled, TSC-based delays will need a different
265 * loops_per_jiffy value to function properly.
266 */
267
268static unsigned int ref_freq = 0;
269static unsigned long loops_per_jiffy_ref = 0;
270
271#ifndef CONFIG_SMP
272static unsigned long fast_gettimeoffset_ref = 0;
273static unsigned int cpu_khz_ref = 0;
274#endif
275
276static int
277time_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
278 void *data)
279{
280 struct cpufreq_freqs *freq = data;
281
282 if (val != CPUFREQ_RESUMECHANGE && val != CPUFREQ_SUSPENDCHANGE)
283 write_seqlock_irq(&xtime_lock);
284 if (!ref_freq) {
285 if (!freq->old){
286 ref_freq = freq->new;
287 goto end;
288 }
289 ref_freq = freq->old;
290 loops_per_jiffy_ref = cpu_data[freq->cpu].loops_per_jiffy;
291#ifndef CONFIG_SMP
292 fast_gettimeoffset_ref = fast_gettimeoffset_quotient;
293 cpu_khz_ref = cpu_khz;
294#endif
295 }
296
297 if ((val == CPUFREQ_PRECHANGE && freq->old < freq->new) ||
298 (val == CPUFREQ_POSTCHANGE && freq->old > freq->new) ||
299 (val == CPUFREQ_RESUMECHANGE)) {
300 if (!(freq->flags & CPUFREQ_CONST_LOOPS))
301 cpu_data[freq->cpu].loops_per_jiffy = cpufreq_scale(loops_per_jiffy_ref, ref_freq, freq->new);
302#ifndef CONFIG_SMP
303 if (cpu_khz)
304 cpu_khz = cpufreq_scale(cpu_khz_ref, ref_freq, freq->new);
305 if (use_tsc) {
306 if (!(freq->flags & CPUFREQ_CONST_LOOPS)) {
307 fast_gettimeoffset_quotient = cpufreq_scale(fast_gettimeoffset_ref, freq->new, ref_freq);
308 set_cyc2ns_scale(cpu_khz);
309 }
310 }
311#endif
312 }
313
314end:
315 if (val != CPUFREQ_RESUMECHANGE && val != CPUFREQ_SUSPENDCHANGE)
316 write_sequnlock_irq(&xtime_lock);
317
318 return 0;
319}
320
321static struct notifier_block time_cpufreq_notifier_block = {
322 .notifier_call = time_cpufreq_notifier
323};
324
325
326static int __init cpufreq_tsc(void)
327{
328 int ret;
329 INIT_WORK(&cpufreq_delayed_get_work, handle_cpufreq_delayed_get, NULL);
330 ret = cpufreq_register_notifier(&time_cpufreq_notifier_block,
331 CPUFREQ_TRANSITION_NOTIFIER);
332 if (!ret)
333 cpufreq_init = 1;
334 return ret;
335}
336core_initcall(cpufreq_tsc);
337
338#else /* CONFIG_CPU_FREQ */
339static inline void cpufreq_delayed_get(void) { return; }
340#endif
341
342int recalibrate_cpu_khz(void)
343{
344#ifndef CONFIG_SMP
345 unsigned int cpu_khz_old = cpu_khz;
346
347 if (cpu_has_tsc) {
348 local_irq_disable();
349 init_cpu_khz();
350 local_irq_enable();
351 cpu_data[0].loops_per_jiffy =
352 cpufreq_scale(cpu_data[0].loops_per_jiffy,
353 cpu_khz_old,
354 cpu_khz);
355 return 0;
356 } else
357 return -ENODEV;
358#else
359 return -ENODEV;
360#endif
361}
362EXPORT_SYMBOL(recalibrate_cpu_khz);
363
364static void mark_offset_tsc(void) 206static void mark_offset_tsc(void)
365{ 207{
366 unsigned long lost,delay; 208 unsigned long lost,delay;
@@ -451,9 +293,6 @@ static void mark_offset_tsc(void)
451 293
452 clock_fallback(); 294 clock_fallback();
453 } 295 }
454 /* ... but give the TSC a fair chance */
455 if (lost_count > 25)
456 cpufreq_delayed_get();
457 } else 296 } else
458 lost_count = 0; 297 lost_count = 0;
459 /* update the monotonic base value */ 298 /* update the monotonic base value */
@@ -578,23 +417,6 @@ static int tsc_resume(void)
578 return 0; 417 return 0;
579} 418}
580 419
581#ifndef CONFIG_X86_TSC
582/* disable flag for tsc. Takes effect by clearing the TSC cpu flag
583 * in cpu/common.c */
584static int __init tsc_setup(char *str)
585{
586 tsc_disable = 1;
587 return 1;
588}
589#else
590static int __init tsc_setup(char *str)
591{
592 printk(KERN_WARNING "notsc: Kernel compiled with CONFIG_X86_TSC, "
593 "cannot disable TSC.\n");
594 return 1;
595}
596#endif
597__setup("notsc", tsc_setup);
598 420
599 421
600 422