diff options
Diffstat (limited to 'arch/i386/kernel/timers/timer_tsc.c')
| -rw-r--r-- | arch/i386/kernel/timers/timer_tsc.c | 178 |
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 f1187ddb0d0fc0..243ec04840793e 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; static struct timer_opts timer_tsc; #endif -static inline void cpufreq_delayed_get(void); - -int tsc_disable __devinitdata = 0; - static int use_tsc; /* Number of usecs that the last interrupt was delayed */ static int delay_at_last_interrupt; @@ -144,30 +140,6 @@ static unsigned long long monotonic_clock_tsc(void) return base + cycles_2_ns(this_offset - last_offset); } -/* - * Scheduler clock - returns current time in nanosec units. - */ -unsigned long long sched_clock(void) -{ - unsigned long long this_offset; - - /* - * In the NUMA case we dont use the TSC as they are not - * synchronized across all CPUs. - */ -#ifndef CONFIG_NUMA - if (!use_tsc) -#endif - /* no locking but a rare wrong value is not a big deal */ - return jiffies_64 * (1000000000 / HZ); - - /* Read the Time Stamp Counter */ - rdtscll(this_offset); - - /* return the value in ns */ - return cycles_2_ns(this_offset); -} - static void delay_tsc(unsigned long loops) { unsigned long bclock, now; @@ -231,136 +203,6 @@ static void mark_offset_tsc_hpet(void) } #endif - -#ifdef CONFIG_CPU_FREQ -#include <linux/workqueue.h> - -static unsigned int cpufreq_delayed_issched = 0; -static unsigned int cpufreq_init = 0; -static struct work_struct cpufreq_delayed_get_work; - -static void handle_cpufreq_delayed_get(void *v) -{ - unsigned int cpu; - for_each_online_cpu(cpu) { - cpufreq_get(cpu); - } - cpufreq_delayed_issched = 0; -} - -/* if we notice lost ticks, schedule a call to cpufreq_get() as it tries - * to verify the CPU frequency the timing core thinks the CPU is running - * at is still correct. - */ -static inline void cpufreq_delayed_get(void) -{ - if (cpufreq_init && !cpufreq_delayed_issched) { - cpufreq_delayed_issched = 1; - printk(KERN_DEBUG "Losing some ticks... checking if CPU frequency changed.\n"); - schedule_work(&cpufreq_delayed_get_work); - } -} - -/* If the CPU frequency is scaled, TSC-based delays will need a different - * loops_per_jiffy value to function properly. - */ - -static unsigned int ref_freq = 0; -static unsigned long loops_per_jiffy_ref = 0; - -#ifndef CONFIG_SMP -static unsigned long fast_gettimeoffset_ref = 0; -static unsigned int cpu_khz_ref = 0; -#endif - -static int -time_cpufreq_notifier(struct notifier_block *nb, unsigned long val, - void *data) -{ - struct cpufreq_freqs *freq = data; - - if (val != CPUFREQ_RESUMECHANGE && val != CPUFREQ_SUSPENDCHANGE) - write_seqlock_irq(&xtime_lock); - if (!ref_freq) { - if (!freq->old){ - ref_freq = freq->new; - goto end; - } - ref_freq = freq->old; - loops_per_jiffy_ref = cpu_data[freq->cpu].loops_per_jiffy; -#ifndef CONFIG_SMP - fast_gettimeoffset_ref = fast_gettimeoffset_quotient; - cpu_khz_ref = cpu_khz; -#endif - } - - if ((val == CPUFREQ_PRECHANGE && freq->old < freq->new) || - (val == CPUFREQ_POSTCHANGE && freq->old > freq->new) || - (val == CPUFREQ_RESUMECHANGE)) { - if (!(freq->flags & CPUFREQ_CONST_LOOPS)) - cpu_data[freq->cpu].loops_per_jiffy = cpufreq_scale(loops_per_jiffy_ref, ref_freq, freq->new); -#ifndef CONFIG_SMP - if (cpu_khz) - cpu_khz = cpufreq_scale(cpu_khz_ref, ref_freq, freq->new); - if (use_tsc) { - if (!(freq->flags & CPUFREQ_CONST_LOOPS)) { - fast_gettimeoffset_quotient = cpufreq_scale(fast_gettimeoffset_ref, freq->new, ref_freq); - set_cyc2ns_scale(cpu_khz); - } - } -#endif - } - -end: - if (val != CPUFREQ_RESUMECHANGE && val != CPUFREQ_SUSPENDCHANGE) - write_sequnlock_irq(&xtime_lock); - - return 0; -} - -static struct notifier_block time_cpufreq_notifier_block = { - .notifier_call = time_cpufreq_notifier -}; - - -static int __init cpufreq_tsc(void) -{ - int ret; - INIT_WORK(&cpufreq_delayed_get_work, handle_cpufreq_delayed_get, NULL); - ret = cpufreq_register_notifier(&time_cpufreq_notifier_block, - CPUFREQ_TRANSITION_NOTIFIER); - if (!ret) - cpufreq_init = 1; - return ret; -} -core_initcall(cpufreq_tsc); - -#else /* CONFIG_CPU_FREQ */ -static inline void cpufreq_delayed_get(void) { return; } -#endif - -int recalibrate_cpu_khz(void) -{ -#ifndef CONFIG_SMP - unsigned int cpu_khz_old = cpu_khz; - - if (cpu_has_tsc) { - local_irq_disable(); - init_cpu_khz(); - local_irq_enable(); - cpu_data[0].loops_per_jiffy = - cpufreq_scale(cpu_data[0].loops_per_jiffy, - cpu_khz_old, - cpu_khz); - return 0; - } else - return -ENODEV; -#else - return -ENODEV; -#endif -} -EXPORT_SYMBOL(recalibrate_cpu_khz); - static void mark_offset_tsc(void) { unsigned long lost,delay; @@ -451,9 +293,6 @@ static void mark_offset_tsc(void) clock_fallback(); } - /* ... but give the TSC a fair chance */ - if (lost_count > 25) - cpufreq_delayed_get(); } else lost_count = 0; /* update the monotonic base value */ @@ -578,23 +417,6 @@ static int tsc_resume(void) return 0; } -#ifndef CONFIG_X86_TSC -/* disable flag for tsc. Takes effect by clearing the TSC cpu flag - * in cpu/common.c */ -static int __init tsc_setup(char *str) -{ - tsc_disable = 1; - return 1; -} -#else -static int __init tsc_setup(char *str) -{ - printk(KERN_WARNING "notsc: Kernel compiled with CONFIG_X86_TSC, " - "cannot disable TSC.\n"); - return 1; -} -#endif -__setup("notsc", tsc_setup); |