ia64/pv_ops/xen: implement xen pv_time_ops. (dcbbecda) · Commits · e / devices / android_kernel_fairphone_FP3

arch/ia64/xen/Makefile

+1 −1

Original line number	Original line	Diff line number	Diff line
	@@ -3,7 +3,7 @@
	#		#

	obj-y := hypercall.o xenivt.o xensetup.o xen_pv_ops.o irq_xen.o \		obj-y := hypercall.o xenivt.o xensetup.o xen_pv_ops.o irq_xen.o \
	hypervisor.o xencomm.o xcom_hcall.o grant-table.o		hypervisor.o xencomm.o xcom_hcall.o grant-table.o time.o

	AFLAGS_xenivt.o += -D__IA64_ASM_PARAVIRTUALIZED_XEN		AFLAGS_xenivt.o += -D__IA64_ASM_PARAVIRTUALIZED_XEN

arch/ia64/xen/time.c

0 → 100644

+180 −0

Original line number	Original line	Diff line number	Diff line
			/******************************************************************************
			* 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/xen/hypervisor.h>

			#include <xen/interface/vcpu.h>

			#include "../kernel/fsyscall_gtod_data.h"

			DEFINE_PER_CPU(struct vcpu_runstate_info, runstate);
			DEFINE_PER_CPU(unsigned long, processed_stolen_time);
			DEFINE_PER_CPU(unsigned long, processed_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(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(processed_blocked_time, cpu) = runstate->time[RUNSTATE_blocked];
			per_cpu(processed_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(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(processed_blocked_time, cpu)))
			blocked = 0;

			if (!time_after_eq(runstate.time[RUNSTATE_runnable] +
			runstate.time[RUNSTATE_offline],
			per_cpu(processed_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_time(NULL, jiffies_to_cputime(stolen));
			account_steal_time(idle_task(cpu), jiffies_to_cputime(blocked));
			run_local_timers();

			if (rcu_pending(cpu))
			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) {
			write_seqlock(&xtime_lock);
			do_timer(stolen + blocked);
			local_cpu_data->itm_next = delta_itm + new_itm;
			write_sequnlock(&xtime_lock);
			} else {
			local_cpu_data->itm_next = delta_itm + new_itm;
			}
			per_cpu(processed_stolen_time, cpu) += NS_PER_TICK * stolen;
			per_cpu(processed_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));
			}

			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,
			};

arch/ia64/xen/time.h

0 → 100644

+23 −0

Original line number	Original line	Diff line number	Diff line
			/******************************************************************************
			* arch/ia64/xen/time.h
			*
			* 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
			*
			*/

			extern struct pv_time_ops xen_time_ops __initdata;

arch/ia64/xen/xen_pv_ops.c

+2 −0

Original line number	Original line	Diff line number	Diff line
	@@ -30,6 +30,7 @@
	#include <asm/xen/privop.h>		#include <asm/xen/privop.h>

	#include "irq_xen.h"		#include "irq_xen.h"
			#include "time.h"

	/***************************************************************************		/***************************************************************************
	* general info		* general info
	@@ -357,6 +358,7 @@ xen_setup_pv_ops(void)
	pv_cpu_ops = xen_cpu_ops;		pv_cpu_ops = xen_cpu_ops;
	pv_iosapic_ops = xen_iosapic_ops;		pv_iosapic_ops = xen_iosapic_ops;
	pv_irq_ops = xen_irq_ops;		pv_irq_ops = xen_irq_ops;
			pv_time_ops = xen_time_ops;

	paravirt_cpu_asm_init(&xen_cpu_asm_switch);		paravirt_cpu_asm_init(&xen_cpu_asm_switch);
	}		}