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Diffstat (limited to 'arch/ia64/kernel/time.c')
-rw-r--r-- | arch/ia64/kernel/time.c | 463 |
1 files changed, 0 insertions, 463 deletions
diff --git a/arch/ia64/kernel/time.c b/arch/ia64/kernel/time.c deleted file mode 100644 index 83ef044b63ef..000000000000 --- a/arch/ia64/kernel/time.c +++ /dev/null @@ -1,463 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * linux/arch/ia64/kernel/time.c - * - * Copyright (C) 1998-2003 Hewlett-Packard Co - * Stephane Eranian <eranian@hpl.hp.com> - * David Mosberger <davidm@hpl.hp.com> - * Copyright (C) 1999 Don Dugger <don.dugger@intel.com> - * Copyright (C) 1999-2000 VA Linux Systems - * Copyright (C) 1999-2000 Walt Drummond <drummond@valinux.com> - */ - -#include <linux/cpu.h> -#include <linux/init.h> -#include <linux/kernel.h> -#include <linux/module.h> -#include <linux/profile.h> -#include <linux/sched.h> -#include <linux/time.h> -#include <linux/nmi.h> -#include <linux/interrupt.h> -#include <linux/efi.h> -#include <linux/timex.h> -#include <linux/timekeeper_internal.h> -#include <linux/platform_device.h> -#include <linux/sched/cputime.h> - -#include <asm/cputime.h> -#include <asm/delay.h> -#include <asm/efi.h> -#include <asm/hw_irq.h> -#include <asm/ptrace.h> -#include <asm/sal.h> -#include <asm/sections.h> - -#include "fsyscall_gtod_data.h" -#include "irq.h" - -static u64 itc_get_cycles(struct clocksource *cs); - -struct fsyscall_gtod_data_t fsyscall_gtod_data; - -struct itc_jitter_data_t itc_jitter_data; - -volatile int time_keeper_id = 0; /* smp_processor_id() of time-keeper */ - -#ifdef CONFIG_IA64_DEBUG_IRQ - -unsigned long last_cli_ip; -EXPORT_SYMBOL(last_cli_ip); - -#endif - -static struct clocksource clocksource_itc = { - .name = "itc", - .rating = 350, - .read = itc_get_cycles, - .mask = CLOCKSOURCE_MASK(64), - .flags = CLOCK_SOURCE_IS_CONTINUOUS, -}; -static struct clocksource *itc_clocksource; - -#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE - -#include <linux/kernel_stat.h> - -extern u64 cycle_to_nsec(u64 cyc); - -void vtime_flush(struct task_struct *tsk) -{ - struct thread_info *ti = task_thread_info(tsk); - u64 delta; - - if (ti->utime) - account_user_time(tsk, cycle_to_nsec(ti->utime)); - - if (ti->gtime) - account_guest_time(tsk, cycle_to_nsec(ti->gtime)); - - if (ti->idle_time) - account_idle_time(cycle_to_nsec(ti->idle_time)); - - if (ti->stime) { - delta = cycle_to_nsec(ti->stime); - account_system_index_time(tsk, delta, CPUTIME_SYSTEM); - } - - if (ti->hardirq_time) { - delta = cycle_to_nsec(ti->hardirq_time); - account_system_index_time(tsk, delta, CPUTIME_IRQ); - } - - if (ti->softirq_time) { - delta = cycle_to_nsec(ti->softirq_time); - account_system_index_time(tsk, delta, CPUTIME_SOFTIRQ); - } - - ti->utime = 0; - ti->gtime = 0; - ti->idle_time = 0; - ti->stime = 0; - ti->hardirq_time = 0; - ti->softirq_time = 0; -} - -/* - * Called from the context switch with interrupts disabled, to charge all - * accumulated times to the current process, and to prepare accounting on - * the next process. - */ -void arch_vtime_task_switch(struct task_struct *prev) -{ - struct thread_info *pi = task_thread_info(prev); - struct thread_info *ni = task_thread_info(current); - - ni->ac_stamp = pi->ac_stamp; - ni->ac_stime = ni->ac_utime = 0; -} - -/* - * Account time for a transition between system, hard irq or soft irq state. - * Note that this function is called with interrupts enabled. - */ -static __u64 vtime_delta(struct task_struct *tsk) -{ - struct thread_info *ti = task_thread_info(tsk); - __u64 now, delta_stime; - - WARN_ON_ONCE(!irqs_disabled()); - - now = ia64_get_itc(); - delta_stime = now - ti->ac_stamp; - ti->ac_stamp = now; - - return delta_stime; -} - -void vtime_account_kernel(struct task_struct *tsk) -{ - struct thread_info *ti = task_thread_info(tsk); - __u64 stime = vtime_delta(tsk); - - if (tsk->flags & PF_VCPU) - ti->gtime += stime; - else - ti->stime += stime; -} -EXPORT_SYMBOL_GPL(vtime_account_kernel); - -void vtime_account_idle(struct task_struct *tsk) -{ - struct thread_info *ti = task_thread_info(tsk); - - ti->idle_time += vtime_delta(tsk); -} - -void vtime_account_softirq(struct task_struct *tsk) -{ - struct thread_info *ti = task_thread_info(tsk); - - ti->softirq_time += vtime_delta(tsk); -} - -void vtime_account_hardirq(struct task_struct *tsk) -{ - struct thread_info *ti = task_thread_info(tsk); - - ti->hardirq_time += vtime_delta(tsk); -} - -#endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ - -static irqreturn_t -timer_interrupt (int irq, void *dev_id) -{ - unsigned long new_itm; - - if (cpu_is_offline(smp_processor_id())) { - return IRQ_HANDLED; - } - - new_itm = local_cpu_data->itm_next; - - if (!time_after(ia64_get_itc(), new_itm)) - printk(KERN_ERR "Oops: timer tick before it's due (itc=%lx,itm=%lx)\n", - ia64_get_itc(), new_itm); - - while (1) { - new_itm += local_cpu_data->itm_delta; - - legacy_timer_tick(smp_processor_id() == time_keeper_id); - - local_cpu_data->itm_next = new_itm; - - if (time_after(new_itm, ia64_get_itc())) - break; - - /* - * Allow IPIs to interrupt the timer loop. - */ - local_irq_enable(); - local_irq_disable(); - } - - do { - /* - * If we're too close to the next clock tick for - * comfort, we increase the safety margin by - * intentionally dropping the next tick(s). We do NOT - * update itm.next because that would force us to call - * xtime_update() which in turn would let our clock run - * too fast (with the potentially devastating effect - * of losing monotony of time). - */ - while (!time_after(new_itm, ia64_get_itc() + local_cpu_data->itm_delta/2)) - new_itm += local_cpu_data->itm_delta; - ia64_set_itm(new_itm); - /* double check, in case we got hit by a (slow) PMI: */ - } while (time_after_eq(ia64_get_itc(), new_itm)); - return IRQ_HANDLED; -} - -/* - * Encapsulate access to the itm structure for SMP. - */ -void -ia64_cpu_local_tick (void) -{ - int cpu = smp_processor_id(); - unsigned long shift = 0, delta; - - /* arrange for the cycle counter to generate a timer interrupt: */ - ia64_set_itv(IA64_TIMER_VECTOR); - - delta = local_cpu_data->itm_delta; - /* - * Stagger the timer tick for each CPU so they don't occur all at (almost) the - * same time: - */ - if (cpu) { - unsigned long hi = 1UL << ia64_fls(cpu); - shift = (2*(cpu - hi) + 1) * delta/hi/2; - } - local_cpu_data->itm_next = ia64_get_itc() + delta + shift; - ia64_set_itm(local_cpu_data->itm_next); -} - -static int nojitter; - -static int __init nojitter_setup(char *str) -{ - nojitter = 1; - printk("Jitter checking for ITC timers disabled\n"); - return 1; -} - -__setup("nojitter", nojitter_setup); - - -void ia64_init_itm(void) -{ - unsigned long platform_base_freq, itc_freq; - struct pal_freq_ratio itc_ratio, proc_ratio; - long status, platform_base_drift, itc_drift; - - /* - * According to SAL v2.6, we need to use a SAL call to determine the platform base - * frequency and then a PAL call to determine the frequency ratio between the ITC - * and the base frequency. - */ - status = ia64_sal_freq_base(SAL_FREQ_BASE_PLATFORM, - &platform_base_freq, &platform_base_drift); - if (status != 0) { - printk(KERN_ERR "SAL_FREQ_BASE_PLATFORM failed: %s\n", ia64_sal_strerror(status)); - } else { - status = ia64_pal_freq_ratios(&proc_ratio, NULL, &itc_ratio); - if (status != 0) - printk(KERN_ERR "PAL_FREQ_RATIOS failed with status=%ld\n", status); - } - if (status != 0) { - /* invent "random" values */ - printk(KERN_ERR - "SAL/PAL failed to obtain frequency info---inventing reasonable values\n"); - platform_base_freq = 100000000; - platform_base_drift = -1; /* no drift info */ - itc_ratio.num = 3; - itc_ratio.den = 1; - } - if (platform_base_freq < 40000000) { - printk(KERN_ERR "Platform base frequency %lu bogus---resetting to 75MHz!\n", - platform_base_freq); - platform_base_freq = 75000000; - platform_base_drift = -1; - } - if (!proc_ratio.den) - proc_ratio.den = 1; /* avoid division by zero */ - if (!itc_ratio.den) - itc_ratio.den = 1; /* avoid division by zero */ - - itc_freq = (platform_base_freq*itc_ratio.num)/itc_ratio.den; - - local_cpu_data->itm_delta = (itc_freq + HZ/2) / HZ; - printk(KERN_DEBUG "CPU %d: base freq=%lu.%03luMHz, ITC ratio=%u/%u, " - "ITC freq=%lu.%03luMHz", smp_processor_id(), - platform_base_freq / 1000000, (platform_base_freq / 1000) % 1000, - itc_ratio.num, itc_ratio.den, itc_freq / 1000000, (itc_freq / 1000) % 1000); - - if (platform_base_drift != -1) { - itc_drift = platform_base_drift*itc_ratio.num/itc_ratio.den; - printk("+/-%ldppm\n", itc_drift); - } else { - itc_drift = -1; - printk("\n"); - } - - local_cpu_data->proc_freq = (platform_base_freq*proc_ratio.num)/proc_ratio.den; - local_cpu_data->itc_freq = itc_freq; - local_cpu_data->cyc_per_usec = (itc_freq + USEC_PER_SEC/2) / USEC_PER_SEC; - local_cpu_data->nsec_per_cyc = ((NSEC_PER_SEC<<IA64_NSEC_PER_CYC_SHIFT) - + itc_freq/2)/itc_freq; - - if (!(sal_platform_features & IA64_SAL_PLATFORM_FEATURE_ITC_DRIFT)) { -#ifdef CONFIG_SMP - /* On IA64 in an SMP configuration ITCs are never accurately synchronized. - * Jitter compensation requires a cmpxchg which may limit - * the scalability of the syscalls for retrieving time. - * The ITC synchronization is usually successful to within a few - * ITC ticks but this is not a sure thing. If you need to improve - * timer performance in SMP situations then boot the kernel with the - * "nojitter" option. However, doing so may result in time fluctuating (maybe - * even going backward) if the ITC offsets between the individual CPUs - * are too large. - */ - if (!nojitter) - itc_jitter_data.itc_jitter = 1; -#endif - } else - /* - * ITC is drifty and we have not synchronized the ITCs in smpboot.c. - * ITC values may fluctuate significantly between processors. - * Clock should not be used for hrtimers. Mark itc as only - * useful for boot and testing. - * - * Note that jitter compensation is off! There is no point of - * synchronizing ITCs since they may be large differentials - * that change over time. - * - * The only way to fix this would be to repeatedly sync the - * ITCs. Until that time we have to avoid ITC. - */ - clocksource_itc.rating = 50; - - /* avoid softlock up message when cpu is unplug and plugged again. */ - touch_softlockup_watchdog(); - - /* Setup the CPU local timer tick */ - ia64_cpu_local_tick(); - - if (!itc_clocksource) { - clocksource_register_hz(&clocksource_itc, - local_cpu_data->itc_freq); - itc_clocksource = &clocksource_itc; - } -} - -static u64 itc_get_cycles(struct clocksource *cs) -{ - unsigned long lcycle, now, ret; - - if (!itc_jitter_data.itc_jitter) - return get_cycles(); - - lcycle = itc_jitter_data.itc_lastcycle; - now = get_cycles(); - if (lcycle && time_after(lcycle, now)) - return lcycle; - - /* - * Keep track of the last timer value returned. - * In an SMP environment, you could lose out in contention of - * cmpxchg. If so, your cmpxchg returns new value which the - * winner of contention updated to. Use the new value instead. - */ - ret = cmpxchg(&itc_jitter_data.itc_lastcycle, lcycle, now); - if (unlikely(ret != lcycle)) - return ret; - - return now; -} - -void read_persistent_clock64(struct timespec64 *ts) -{ - efi_gettimeofday(ts); -} - -void __init -time_init (void) -{ - register_percpu_irq(IA64_TIMER_VECTOR, timer_interrupt, IRQF_IRQPOLL, - "timer"); - ia64_init_itm(); -} - -/* - * Generic udelay assumes that if preemption is allowed and the thread - * migrates to another CPU, that the ITC values are synchronized across - * all CPUs. - */ -static void -ia64_itc_udelay (unsigned long usecs) -{ - unsigned long start = ia64_get_itc(); - unsigned long end = start + usecs*local_cpu_data->cyc_per_usec; - - while (time_before(ia64_get_itc(), end)) - cpu_relax(); -} - -void (*ia64_udelay)(unsigned long usecs) = &ia64_itc_udelay; - -void -udelay (unsigned long usecs) -{ - (*ia64_udelay)(usecs); -} -EXPORT_SYMBOL(udelay); - -/* IA64 doesn't cache the timezone */ -void update_vsyscall_tz(void) -{ -} - -void update_vsyscall(struct timekeeper *tk) -{ - write_seqcount_begin(&fsyscall_gtod_data.seq); - - /* copy vsyscall data */ - fsyscall_gtod_data.clk_mask = tk->tkr_mono.mask; - fsyscall_gtod_data.clk_mult = tk->tkr_mono.mult; - fsyscall_gtod_data.clk_shift = tk->tkr_mono.shift; - fsyscall_gtod_data.clk_fsys_mmio = tk->tkr_mono.clock->archdata.fsys_mmio; - fsyscall_gtod_data.clk_cycle_last = tk->tkr_mono.cycle_last; - - fsyscall_gtod_data.wall_time.sec = tk->xtime_sec; - fsyscall_gtod_data.wall_time.snsec = tk->tkr_mono.xtime_nsec; - - fsyscall_gtod_data.monotonic_time.sec = tk->xtime_sec - + tk->wall_to_monotonic.tv_sec; - fsyscall_gtod_data.monotonic_time.snsec = tk->tkr_mono.xtime_nsec - + ((u64)tk->wall_to_monotonic.tv_nsec - << tk->tkr_mono.shift); - - /* normalize */ - while (fsyscall_gtod_data.monotonic_time.snsec >= - (((u64)NSEC_PER_SEC) << tk->tkr_mono.shift)) { - fsyscall_gtod_data.monotonic_time.snsec -= - ((u64)NSEC_PER_SEC) << tk->tkr_mono.shift; - fsyscall_gtod_data.monotonic_time.sec++; - } - - write_seqcount_end(&fsyscall_gtod_data.seq); -} - |