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-rw-r--r--arch/ia64/kernel/time.c463
1 files changed, 0 insertions, 463 deletions
diff --git a/arch/ia64/kernel/time.c b/arch/ia64/kernel/time.c
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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);
-}
-