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Diffstat (limited to 'arch/i386/kernel/vmitime.c')
-rw-r--r--arch/i386/kernel/vmitime.c482
1 files changed, 0 insertions, 482 deletions
diff --git a/arch/i386/kernel/vmitime.c b/arch/i386/kernel/vmitime.c
deleted file mode 100644
index 9dfb17739b67..000000000000
--- a/arch/i386/kernel/vmitime.c
+++ /dev/null
@@ -1,482 +0,0 @@
-/*
- * VMI paravirtual timer support routines.
- *
- * Copyright (C) 2005, VMware, Inc.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
- * NON INFRINGEMENT. See the GNU General Public License for more
- * details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- *
- * Send feedback to dhecht@vmware.com
- *
- */
-
-/*
- * Portions of this code from arch/i386/kernel/timers/timer_tsc.c.
- * Portions of the CONFIG_NO_IDLE_HZ code from arch/s390/kernel/time.c.
- * See comments there for proper credits.
- */
-
-#include <linux/spinlock.h>
-#include <linux/init.h>
-#include <linux/errno.h>
-#include <linux/jiffies.h>
-#include <linux/interrupt.h>
-#include <linux/kernel_stat.h>
-#include <linux/rcupdate.h>
-#include <linux/clocksource.h>
-
-#include <asm/timer.h>
-#include <asm/io.h>
-#include <asm/apic.h>
-#include <asm/div64.h>
-#include <asm/timer.h>
-#include <asm/desc.h>
-
-#include <asm/vmi.h>
-#include <asm/vmi_time.h>
-
-#include <mach_timer.h>
-#include <io_ports.h>
-
-#ifdef CONFIG_X86_LOCAL_APIC
-#define VMI_ALARM_WIRING VMI_ALARM_WIRED_LVTT
-#else
-#define VMI_ALARM_WIRING VMI_ALARM_WIRED_IRQ0
-#endif
-
-/* Cached VMI operations */
-struct vmi_timer_ops vmi_timer_ops;
-
-#ifdef CONFIG_NO_IDLE_HZ
-
-/* /proc/sys/kernel/hz_timer state. */
-int sysctl_hz_timer;
-
-/* Some stats */
-static DEFINE_PER_CPU(unsigned long, vmi_idle_no_hz_irqs);
-static DEFINE_PER_CPU(unsigned long, vmi_idle_no_hz_jiffies);
-static DEFINE_PER_CPU(unsigned long, idle_start_jiffies);
-
-#endif /* CONFIG_NO_IDLE_HZ */
-
-/* Number of alarms per second. By default this is CONFIG_VMI_ALARM_HZ. */
-static int alarm_hz = CONFIG_VMI_ALARM_HZ;
-
-/* Cache of the value get_cycle_frequency / HZ. */
-static signed long long cycles_per_jiffy;
-
-/* Cache of the value get_cycle_frequency / alarm_hz. */
-static signed long long cycles_per_alarm;
-
-/* The number of cycles accounted for by the 'jiffies'/'xtime' count.
- * Protected by xtime_lock. */
-static unsigned long long real_cycles_accounted_system;
-
-/* The number of cycles accounted for by update_process_times(), per cpu. */
-static DEFINE_PER_CPU(unsigned long long, process_times_cycles_accounted_cpu);
-
-/* The number of stolen cycles accounted, per cpu. */
-static DEFINE_PER_CPU(unsigned long long, stolen_cycles_accounted_cpu);
-
-/* Clock source. */
-static cycle_t read_real_cycles(void)
-{
- return vmi_timer_ops.get_cycle_counter(VMI_CYCLES_REAL);
-}
-
-static cycle_t read_available_cycles(void)
-{
- return vmi_timer_ops.get_cycle_counter(VMI_CYCLES_AVAILABLE);
-}
-
-#if 0
-static cycle_t read_stolen_cycles(void)
-{
- return vmi_timer_ops.get_cycle_counter(VMI_CYCLES_STOLEN);
-}
-#endif /* 0 */
-
-static struct clocksource clocksource_vmi = {
- .name = "vmi-timer",
- .rating = 450,
- .read = read_real_cycles,
- .mask = CLOCKSOURCE_MASK(64),
- .mult = 0, /* to be set */
- .shift = 22,
- .flags = CLOCK_SOURCE_IS_CONTINUOUS,
-};
-
-
-/* Timer interrupt handler. */
-static irqreturn_t vmi_timer_interrupt(int irq, void *dev_id);
-
-static struct irqaction vmi_timer_irq = {
- .handler = vmi_timer_interrupt,
- .flags = IRQF_DISABLED,
- .mask = CPU_MASK_NONE,
- .name = "VMI-alarm",
-};
-
-/* Alarm rate */
-static int __init vmi_timer_alarm_rate_setup(char* str)
-{
- int alarm_rate;
- if (get_option(&str, &alarm_rate) == 1 && alarm_rate > 0) {
- alarm_hz = alarm_rate;
- printk(KERN_WARNING "VMI timer alarm HZ set to %d\n", alarm_hz);
- }
- return 1;
-}
-__setup("vmi_timer_alarm_hz=", vmi_timer_alarm_rate_setup);
-
-
-/* Initialization */
-static void vmi_get_wallclock_ts(struct timespec *ts)
-{
- unsigned long long wallclock;
- wallclock = vmi_timer_ops.get_wallclock(); // nsec units
- ts->tv_nsec = do_div(wallclock, 1000000000);
- ts->tv_sec = wallclock;
-}
-
-unsigned long vmi_get_wallclock(void)
-{
- struct timespec ts;
- vmi_get_wallclock_ts(&ts);
- return ts.tv_sec;
-}
-
-int vmi_set_wallclock(unsigned long now)
-{
- return -1;
-}
-
-unsigned long long vmi_get_sched_cycles(void)
-{
- return read_available_cycles();
-}
-
-unsigned long vmi_cpu_khz(void)
-{
- unsigned long long khz;
-
- khz = vmi_timer_ops.get_cycle_frequency();
- (void)do_div(khz, 1000);
- return khz;
-}
-
-void __init vmi_time_init(void)
-{
- unsigned long long cycles_per_sec, cycles_per_msec;
- unsigned long flags;
-
- local_irq_save(flags);
- setup_irq(0, &vmi_timer_irq);
-#ifdef CONFIG_X86_LOCAL_APIC
- set_intr_gate(LOCAL_TIMER_VECTOR, apic_vmi_timer_interrupt);
-#endif
-
- real_cycles_accounted_system = read_real_cycles();
- per_cpu(process_times_cycles_accounted_cpu, 0) = read_available_cycles();
-
- cycles_per_sec = vmi_timer_ops.get_cycle_frequency();
- cycles_per_jiffy = cycles_per_sec;
- (void)do_div(cycles_per_jiffy, HZ);
- cycles_per_alarm = cycles_per_sec;
- (void)do_div(cycles_per_alarm, alarm_hz);
- cycles_per_msec = cycles_per_sec;
- (void)do_div(cycles_per_msec, 1000);
-
- printk(KERN_WARNING "VMI timer cycles/sec = %llu ; cycles/jiffy = %llu ;"
- "cycles/alarm = %llu\n", cycles_per_sec, cycles_per_jiffy,
- cycles_per_alarm);
-
- clocksource_vmi.mult = clocksource_khz2mult(cycles_per_msec,
- clocksource_vmi.shift);
- if (clocksource_register(&clocksource_vmi))
- printk(KERN_WARNING "Error registering VMITIME clocksource.");
-
- /* Disable PIT. */
- outb_p(0x3a, PIT_MODE); /* binary, mode 5, LSB/MSB, ch 0 */
-
- /* schedule the alarm. do this in phase with process_times_cycles_accounted_cpu
- * reduce the latency calling update_process_times. */
- vmi_timer_ops.set_alarm(
- VMI_ALARM_WIRED_IRQ0 | VMI_ALARM_IS_PERIODIC | VMI_CYCLES_AVAILABLE,
- per_cpu(process_times_cycles_accounted_cpu, 0) + cycles_per_alarm,
- cycles_per_alarm);
-
- local_irq_restore(flags);
-}
-
-#ifdef CONFIG_X86_LOCAL_APIC
-
-void __init vmi_timer_setup_boot_alarm(void)
-{
- local_irq_disable();
-
- /* Route the interrupt to the correct vector. */
- apic_write_around(APIC_LVTT, LOCAL_TIMER_VECTOR);
-
- /* Cancel the IRQ0 wired alarm, and setup the LVTT alarm. */
- vmi_timer_ops.cancel_alarm(VMI_CYCLES_AVAILABLE);
- vmi_timer_ops.set_alarm(
- VMI_ALARM_WIRED_LVTT | VMI_ALARM_IS_PERIODIC | VMI_CYCLES_AVAILABLE,
- per_cpu(process_times_cycles_accounted_cpu, 0) + cycles_per_alarm,
- cycles_per_alarm);
- local_irq_enable();
-}
-
-/* Initialize the time accounting variables for an AP on an SMP system.
- * Also, set the local alarm for the AP. */
-void __devinit vmi_timer_setup_secondary_alarm(void)
-{
- int cpu = smp_processor_id();
-
- /* Route the interrupt to the correct vector. */
- apic_write_around(APIC_LVTT, LOCAL_TIMER_VECTOR);
-
- per_cpu(process_times_cycles_accounted_cpu, cpu) = read_available_cycles();
-
- vmi_timer_ops.set_alarm(
- VMI_ALARM_WIRED_LVTT | VMI_ALARM_IS_PERIODIC | VMI_CYCLES_AVAILABLE,
- per_cpu(process_times_cycles_accounted_cpu, cpu) + cycles_per_alarm,
- cycles_per_alarm);
-}
-
-#endif
-
-/* Update system wide (real) time accounting (e.g. jiffies, xtime). */
-static void vmi_account_real_cycles(unsigned long long cur_real_cycles)
-{
- long long cycles_not_accounted;
-
- write_seqlock(&xtime_lock);
-
- cycles_not_accounted = cur_real_cycles - real_cycles_accounted_system;
- while (cycles_not_accounted >= cycles_per_jiffy) {
- /* systems wide jiffies. */
- do_timer(1);
-
- cycles_not_accounted -= cycles_per_jiffy;
- real_cycles_accounted_system += cycles_per_jiffy;
- }
-
- write_sequnlock(&xtime_lock);
-}
-
-/* Update per-cpu process times. */
-static void vmi_account_process_times_cycles(struct pt_regs *regs, int cpu,
- unsigned long long cur_process_times_cycles)
-{
- long long cycles_not_accounted;
- cycles_not_accounted = cur_process_times_cycles -
- per_cpu(process_times_cycles_accounted_cpu, cpu);
-
- while (cycles_not_accounted >= cycles_per_jiffy) {
- /* Account time to the current process. This includes
- * calling into the scheduler to decrement the timeslice
- * and possibly reschedule.*/
- update_process_times(user_mode(regs));
- /* XXX handle /proc/profile multiplier. */
- profile_tick(CPU_PROFILING);
-
- cycles_not_accounted -= cycles_per_jiffy;
- per_cpu(process_times_cycles_accounted_cpu, cpu) += cycles_per_jiffy;
- }
-}
-
-#ifdef CONFIG_NO_IDLE_HZ
-/* Update per-cpu idle times. Used when a no-hz halt is ended. */
-static void vmi_account_no_hz_idle_cycles(int cpu,
- unsigned long long cur_process_times_cycles)
-{
- long long cycles_not_accounted;
- unsigned long no_idle_hz_jiffies = 0;
-
- cycles_not_accounted = cur_process_times_cycles -
- per_cpu(process_times_cycles_accounted_cpu, cpu);
-
- while (cycles_not_accounted >= cycles_per_jiffy) {
- no_idle_hz_jiffies++;
- cycles_not_accounted -= cycles_per_jiffy;
- per_cpu(process_times_cycles_accounted_cpu, cpu) += cycles_per_jiffy;
- }
- /* Account time to the idle process. */
- account_steal_time(idle_task(cpu), jiffies_to_cputime(no_idle_hz_jiffies));
-}
-#endif
-
-/* Update per-cpu stolen time. */
-static void vmi_account_stolen_cycles(int cpu,
- unsigned long long cur_real_cycles,
- unsigned long long cur_avail_cycles)
-{
- long long stolen_cycles_not_accounted;
- unsigned long stolen_jiffies = 0;
-
- if (cur_real_cycles < cur_avail_cycles)
- return;
-
- stolen_cycles_not_accounted = cur_real_cycles - cur_avail_cycles -
- per_cpu(stolen_cycles_accounted_cpu, cpu);
-
- while (stolen_cycles_not_accounted >= cycles_per_jiffy) {
- stolen_jiffies++;
- stolen_cycles_not_accounted -= cycles_per_jiffy;
- per_cpu(stolen_cycles_accounted_cpu, cpu) += cycles_per_jiffy;
- }
- /* HACK: pass NULL to force time onto cpustat->steal. */
- account_steal_time(NULL, jiffies_to_cputime(stolen_jiffies));
-}
-
-/* Body of either IRQ0 interrupt handler (UP no local-APIC) or
- * local-APIC LVTT interrupt handler (UP & local-APIC or SMP). */
-static void vmi_local_timer_interrupt(int cpu)
-{
- unsigned long long cur_real_cycles, cur_process_times_cycles;
-
- cur_real_cycles = read_real_cycles();
- cur_process_times_cycles = read_available_cycles();
- /* Update system wide (real) time state (xtime, jiffies). */
- vmi_account_real_cycles(cur_real_cycles);
- /* Update per-cpu process times. */
- vmi_account_process_times_cycles(get_irq_regs(), cpu, cur_process_times_cycles);
- /* Update time stolen from this cpu by the hypervisor. */
- vmi_account_stolen_cycles(cpu, cur_real_cycles, cur_process_times_cycles);
-}
-
-#ifdef CONFIG_NO_IDLE_HZ
-
-/* Must be called only from idle loop, with interrupts disabled. */
-int vmi_stop_hz_timer(void)
-{
- /* Note that cpu_set, cpu_clear are (SMP safe) atomic on x86. */
-
- unsigned long seq, next;
- unsigned long long real_cycles_expiry;
- int cpu = smp_processor_id();
-
- BUG_ON(!irqs_disabled());
- if (sysctl_hz_timer != 0)
- return 0;
-
- cpu_set(cpu, nohz_cpu_mask);
- smp_mb();
-
- if (rcu_needs_cpu(cpu) || local_softirq_pending() ||
- (next = next_timer_interrupt(),
- time_before_eq(next, jiffies + HZ/CONFIG_VMI_ALARM_HZ))) {
- cpu_clear(cpu, nohz_cpu_mask);
- return 0;
- }
-
- /* Convert jiffies to the real cycle counter. */
- do {
- seq = read_seqbegin(&xtime_lock);
- real_cycles_expiry = real_cycles_accounted_system +
- (long)(next - jiffies) * cycles_per_jiffy;
- } while (read_seqretry(&xtime_lock, seq));
-
- /* This cpu is going idle. Disable the periodic alarm. */
- vmi_timer_ops.cancel_alarm(VMI_CYCLES_AVAILABLE);
- per_cpu(idle_start_jiffies, cpu) = jiffies;
- /* Set the real time alarm to expire at the next event. */
- vmi_timer_ops.set_alarm(
- VMI_ALARM_WIRING | VMI_ALARM_IS_ONESHOT | VMI_CYCLES_REAL,
- real_cycles_expiry, 0);
- return 1;
-}
-
-static void vmi_reenable_hz_timer(int cpu)
-{
- /* For /proc/vmi/info idle_hz stat. */
- per_cpu(vmi_idle_no_hz_jiffies, cpu) += jiffies - per_cpu(idle_start_jiffies, cpu);
- per_cpu(vmi_idle_no_hz_irqs, cpu)++;
-
- /* Don't bother explicitly cancelling the one-shot alarm -- at
- * worse we will receive a spurious timer interrupt. */
- vmi_timer_ops.set_alarm(
- VMI_ALARM_WIRING | VMI_ALARM_IS_PERIODIC | VMI_CYCLES_AVAILABLE,
- per_cpu(process_times_cycles_accounted_cpu, cpu) + cycles_per_alarm,
- cycles_per_alarm);
- /* Indicate this cpu is no longer nohz idle. */
- cpu_clear(cpu, nohz_cpu_mask);
-}
-
-/* Called from interrupt handlers when (local) HZ timer is disabled. */
-void vmi_account_time_restart_hz_timer(void)
-{
- unsigned long long cur_real_cycles, cur_process_times_cycles;
- int cpu = smp_processor_id();
-
- BUG_ON(!irqs_disabled());
- /* Account the time during which the HZ timer was disabled. */
- cur_real_cycles = read_real_cycles();
- cur_process_times_cycles = read_available_cycles();
- /* Update system wide (real) time state (xtime, jiffies). */
- vmi_account_real_cycles(cur_real_cycles);
- /* Update per-cpu idle times. */
- vmi_account_no_hz_idle_cycles(cpu, cur_process_times_cycles);
- /* Update time stolen from this cpu by the hypervisor. */
- vmi_account_stolen_cycles(cpu, cur_real_cycles, cur_process_times_cycles);
- /* Reenable the hz timer. */
- vmi_reenable_hz_timer(cpu);
-}
-
-#endif /* CONFIG_NO_IDLE_HZ */
-
-/* UP (and no local-APIC) VMI-timer alarm interrupt handler.
- * Handler for IRQ0. Not used when SMP or X86_LOCAL_APIC after
- * APIC setup and setup_boot_vmi_alarm() is called. */
-static irqreturn_t vmi_timer_interrupt(int irq, void *dev_id)
-{
- vmi_local_timer_interrupt(smp_processor_id());
- return IRQ_HANDLED;
-}
-
-#ifdef CONFIG_X86_LOCAL_APIC
-
-/* SMP VMI-timer alarm interrupt handler. Handler for LVTT vector.
- * Also used in UP when CONFIG_X86_LOCAL_APIC.
- * The wrapper code is from arch/i386/kernel/apic.c#smp_apic_timer_interrupt. */
-void smp_apic_vmi_timer_interrupt(struct pt_regs *regs)
-{
- struct pt_regs *old_regs = set_irq_regs(regs);
- int cpu = smp_processor_id();
-
- /*
- * the NMI deadlock-detector uses this.
- */
- per_cpu(irq_stat,cpu).apic_timer_irqs++;
-
- /*
- * NOTE! We'd better ACK the irq immediately,
- * because timer handling can be slow.
- */
- ack_APIC_irq();
-
- /*
- * update_process_times() expects us to have done irq_enter().
- * Besides, if we don't timer interrupts ignore the global
- * interrupt lock, which is the WrongThing (tm) to do.
- */
- irq_enter();
- vmi_local_timer_interrupt(cpu);
- irq_exit();
- set_irq_regs(old_regs);
-}
-
-#endif /* CONFIG_X86_LOCAL_APIC */