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Diffstat (limited to 'arch/ia64/xen/time.c')
-rw-r--r-- | arch/ia64/xen/time.c | 257 |
1 files changed, 0 insertions, 257 deletions
diff --git a/arch/ia64/xen/time.c b/arch/ia64/xen/time.c deleted file mode 100644 index 1f8244a..0000000 --- a/arch/ia64/xen/time.c +++ /dev/null @@ -1,257 +0,0 @@ -/****************************************************************************** - * arch/ia64/xen/time.c - * - * Copyright (c) 2008 Isaku Yamahata <yamahata at valinux co jp> - * VA Linux Systems Japan K.K. - * - * 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. 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA - * - */ - -#include <linux/delay.h> -#include <linux/kernel_stat.h> -#include <linux/posix-timers.h> -#include <linux/irq.h> -#include <linux/clocksource.h> - -#include <asm/timex.h> - -#include <asm/xen/hypervisor.h> - -#include <xen/interface/vcpu.h> - -#include "../kernel/fsyscall_gtod_data.h" - -static DEFINE_PER_CPU(struct vcpu_runstate_info, xen_runstate); -static DEFINE_PER_CPU(unsigned long, xen_stolen_time); -static DEFINE_PER_CPU(unsigned long, xen_blocked_time); - -/* taken from i386/kernel/time-xen.c */ -static void xen_init_missing_ticks_accounting(int cpu) -{ - struct vcpu_register_runstate_memory_area area; - struct vcpu_runstate_info *runstate = &per_cpu(xen_runstate, cpu); - int rc; - - memset(runstate, 0, sizeof(*runstate)); - - area.addr.v = runstate; - rc = HYPERVISOR_vcpu_op(VCPUOP_register_runstate_memory_area, cpu, - &area); - WARN_ON(rc && rc != -ENOSYS); - - per_cpu(xen_blocked_time, cpu) = runstate->time[RUNSTATE_blocked]; - per_cpu(xen_stolen_time, cpu) = runstate->time[RUNSTATE_runnable] - + runstate->time[RUNSTATE_offline]; -} - -/* - * Runstate accounting - */ -/* stolen from arch/x86/xen/time.c */ -static void get_runstate_snapshot(struct vcpu_runstate_info *res) -{ - u64 state_time; - struct vcpu_runstate_info *state; - - BUG_ON(preemptible()); - - state = &__get_cpu_var(xen_runstate); - - /* - * The runstate info is always updated by the hypervisor on - * the current CPU, so there's no need to use anything - * stronger than a compiler barrier when fetching it. - */ - do { - state_time = state->state_entry_time; - rmb(); - *res = *state; - rmb(); - } while (state->state_entry_time != state_time); -} - -#define NS_PER_TICK (1000000000LL/HZ) - -static unsigned long -consider_steal_time(unsigned long new_itm) -{ - unsigned long stolen, blocked; - unsigned long delta_itm = 0, stolentick = 0; - int cpu = smp_processor_id(); - struct vcpu_runstate_info runstate; - struct task_struct *p = current; - - get_runstate_snapshot(&runstate); - - /* - * Check for vcpu migration effect - * In this case, itc value is reversed. - * This causes huge stolen value. - * This function just checks and reject this effect. - */ - if (!time_after_eq(runstate.time[RUNSTATE_blocked], - per_cpu(xen_blocked_time, cpu))) - blocked = 0; - - if (!time_after_eq(runstate.time[RUNSTATE_runnable] + - runstate.time[RUNSTATE_offline], - per_cpu(xen_stolen_time, cpu))) - stolen = 0; - - if (!time_after(delta_itm + new_itm, ia64_get_itc())) - stolentick = ia64_get_itc() - new_itm; - - do_div(stolentick, NS_PER_TICK); - stolentick++; - - do_div(stolen, NS_PER_TICK); - - if (stolen > stolentick) - stolen = stolentick; - - stolentick -= stolen; - do_div(blocked, NS_PER_TICK); - - if (blocked > stolentick) - blocked = stolentick; - - if (stolen > 0 || blocked > 0) { - account_steal_ticks(stolen); - account_idle_ticks(blocked); - run_local_timers(); - - rcu_check_callbacks(cpu, user_mode(get_irq_regs())); - - scheduler_tick(); - run_posix_cpu_timers(p); - delta_itm += local_cpu_data->itm_delta * (stolen + blocked); - - if (cpu == time_keeper_id) - xtime_update(stolen + blocked); - - local_cpu_data->itm_next = delta_itm + new_itm; - - per_cpu(xen_stolen_time, cpu) += NS_PER_TICK * stolen; - per_cpu(xen_blocked_time, cpu) += NS_PER_TICK * blocked; - } - return delta_itm; -} - -static int xen_do_steal_accounting(unsigned long *new_itm) -{ - unsigned long delta_itm; - delta_itm = consider_steal_time(*new_itm); - *new_itm += delta_itm; - if (time_after(*new_itm, ia64_get_itc()) && delta_itm) - return 1; - - return 0; -} - -static void xen_itc_jitter_data_reset(void) -{ - u64 lcycle, ret; - - do { - lcycle = itc_jitter_data.itc_lastcycle; - ret = cmpxchg(&itc_jitter_data.itc_lastcycle, lcycle, 0); - } while (unlikely(ret != lcycle)); -} - -/* based on xen_sched_clock() in arch/x86/xen/time.c. */ -/* - * This relies on HAVE_UNSTABLE_SCHED_CLOCK. If it can't be defined, - * something similar logic should be implemented here. - */ -/* - * Xen sched_clock implementation. Returns the number of unstolen - * nanoseconds, which is nanoseconds the VCPU spent in RUNNING+BLOCKED - * states. - */ -static unsigned long long xen_sched_clock(void) -{ - struct vcpu_runstate_info runstate; - - unsigned long long now; - unsigned long long offset; - unsigned long long ret; - - /* - * Ideally sched_clock should be called on a per-cpu basis - * anyway, so preempt should already be disabled, but that's - * not current practice at the moment. - */ - preempt_disable(); - - /* - * both ia64_native_sched_clock() and xen's runstate are - * based on mAR.ITC. So difference of them makes sense. - */ - now = ia64_native_sched_clock(); - - get_runstate_snapshot(&runstate); - - WARN_ON(runstate.state != RUNSTATE_running); - - offset = 0; - if (now > runstate.state_entry_time) - offset = now - runstate.state_entry_time; - ret = runstate.time[RUNSTATE_blocked] + - runstate.time[RUNSTATE_running] + - offset; - - preempt_enable(); - - return ret; -} - -struct pv_time_ops xen_time_ops __initdata = { - .init_missing_ticks_accounting = xen_init_missing_ticks_accounting, - .do_steal_accounting = xen_do_steal_accounting, - .clocksource_resume = xen_itc_jitter_data_reset, - .sched_clock = xen_sched_clock, -}; - -/* Called after suspend, to resume time. */ -static void xen_local_tick_resume(void) -{ - /* Just trigger a tick. */ - ia64_cpu_local_tick(); - touch_softlockup_watchdog(); -} - -void -xen_timer_resume(void) -{ - unsigned int cpu; - - xen_local_tick_resume(); - - for_each_online_cpu(cpu) - xen_init_missing_ticks_accounting(cpu); -} - -static void ia64_cpu_local_tick_fn(void *unused) -{ - xen_local_tick_resume(); - xen_init_missing_ticks_accounting(smp_processor_id()); -} - -void -xen_timer_resume_on_aps(void) -{ - smp_call_function(&ia64_cpu_local_tick_fn, NULL, 1); -} |