diff options
Diffstat (limited to 'arch/arm')
| -rw-r--r-- | arch/arm/Kconfig | 20 | ||||
| -rw-r--r-- | arch/arm/include/asm/paravirt.h | 20 | ||||
| -rw-r--r-- | arch/arm/include/asm/xen/hypercall.h | 7 | ||||
| -rw-r--r-- | arch/arm/include/asm/xen/interface.h | 3 | ||||
| -rw-r--r-- | arch/arm/kernel/Makefile | 1 | ||||
| -rw-r--r-- | arch/arm/kernel/paravirt.c | 25 | ||||
| -rw-r--r-- | arch/arm/xen/enlighten.c | 95 | ||||
| -rw-r--r-- | arch/arm/xen/hypercall.S | 1 |
8 files changed, 172 insertions, 0 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index b0e7ff176028..426115f7cb63 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1824,6 +1824,25 @@ config SWIOTLB config IOMMU_HELPER def_bool SWIOTLB +config PARAVIRT + bool "Enable paravirtualization code" + help + This changes the kernel so it can modify itself when it is run + under a hypervisor, potentially improving performance significantly + over full virtualization. + +config PARAVIRT_TIME_ACCOUNTING + bool "Paravirtual steal time accounting" + select PARAVIRT + default n + help + Select this option to enable fine granularity task steal time + accounting. Time spent executing other tasks in parallel with + the current vCPU is discounted from the vCPU power. To account for + that, there can be a small performance impact. + + If in doubt, say N here. + config XEN_DOM0 def_bool y depends on XEN @@ -1837,6 +1856,7 @@ config XEN select ARCH_DMA_ADDR_T_64BIT select ARM_PSCI select SWIOTLB_XEN + select PARAVIRT help Say Y if you want to run Linux in a Virtual Machine on Xen on ARM. diff --git a/arch/arm/include/asm/paravirt.h b/arch/arm/include/asm/paravirt.h new file mode 100644 index 000000000000..8435ff591386 --- /dev/null +++ b/arch/arm/include/asm/paravirt.h @@ -0,0 +1,20 @@ +#ifndef _ASM_ARM_PARAVIRT_H +#define _ASM_ARM_PARAVIRT_H + +#ifdef CONFIG_PARAVIRT +struct static_key; +extern struct static_key paravirt_steal_enabled; +extern struct static_key paravirt_steal_rq_enabled; + +struct pv_time_ops { + unsigned long long (*steal_clock)(int cpu); +}; +extern struct pv_time_ops pv_time_ops; + +static inline u64 paravirt_steal_clock(int cpu) +{ + return pv_time_ops.steal_clock(cpu); +} +#endif + +#endif diff --git a/arch/arm/include/asm/xen/hypercall.h b/arch/arm/include/asm/xen/hypercall.h index 712b50e0a6dc..d769972db8cb 100644 --- a/arch/arm/include/asm/xen/hypercall.h +++ b/arch/arm/include/asm/xen/hypercall.h @@ -35,6 +35,7 @@ #include <xen/interface/xen.h> #include <xen/interface/sched.h> +#include <xen/interface/platform.h> long privcmd_call(unsigned call, unsigned long a1, unsigned long a2, unsigned long a3, @@ -49,6 +50,12 @@ int HYPERVISOR_memory_op(unsigned int cmd, void *arg); int HYPERVISOR_physdev_op(int cmd, void *arg); int HYPERVISOR_vcpu_op(int cmd, int vcpuid, void *extra_args); int HYPERVISOR_tmem_op(void *arg); +int HYPERVISOR_platform_op_raw(void *arg); +static inline int HYPERVISOR_platform_op(struct xen_platform_op *op) +{ + op->interface_version = XENPF_INTERFACE_VERSION; + return HYPERVISOR_platform_op_raw(op); +} int HYPERVISOR_multicall(struct multicall_entry *calls, uint32_t nr); static inline int diff --git a/arch/arm/include/asm/xen/interface.h b/arch/arm/include/asm/xen/interface.h index 50066006e6bd..75d596862892 100644 --- a/arch/arm/include/asm/xen/interface.h +++ b/arch/arm/include/asm/xen/interface.h @@ -27,6 +27,8 @@ (hnd).p = val; \ } while (0) +#define __HYPERVISOR_platform_op_raw __HYPERVISOR_platform_op + #ifndef __ASSEMBLY__ /* Explicitly size integers that represent pfns in the interface with * Xen so that we can have one ABI that works for 32 and 64 bit guests. @@ -76,6 +78,7 @@ struct pvclock_wall_clock { u32 version; u32 sec; u32 nsec; + u32 sec_hi; } __attribute__((__packed__)); #endif diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index f729085ece28..2c5f160be65e 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -81,6 +81,7 @@ obj-$(CONFIG_EFI) += efi.o ifneq ($(CONFIG_ARCH_EBSA110),y) obj-y += io.o endif +obj-$(CONFIG_PARAVIRT) += paravirt.o head-y := head$(MMUEXT).o obj-$(CONFIG_DEBUG_LL) += debug.o diff --git a/arch/arm/kernel/paravirt.c b/arch/arm/kernel/paravirt.c new file mode 100644 index 000000000000..53f371ed4568 --- /dev/null +++ b/arch/arm/kernel/paravirt.c @@ -0,0 +1,25 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * 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. + * + * Copyright (C) 2013 Citrix Systems + * + * Author: Stefano Stabellini <stefano.stabellini@eu.citrix.com> + */ + +#include <linux/export.h> +#include <linux/jump_label.h> +#include <linux/types.h> +#include <asm/paravirt.h> + +struct static_key paravirt_steal_enabled; +struct static_key paravirt_steal_rq_enabled; + +struct pv_time_ops pv_time_ops; +EXPORT_SYMBOL_GPL(pv_time_ops); diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c index fc7ea529f462..75cd7345c654 100644 --- a/arch/arm/xen/enlighten.c +++ b/arch/arm/xen/enlighten.c @@ -12,6 +12,7 @@ #include <xen/page.h> #include <xen/interface/sched.h> #include <xen/xen-ops.h> +#include <asm/paravirt.h> #include <asm/xen/hypervisor.h> #include <asm/xen/hypercall.h> #include <asm/system_misc.h> @@ -25,6 +26,10 @@ #include <linux/cpufreq.h> #include <linux/cpu.h> #include <linux/console.h> +#include <linux/pvclock_gtod.h> +#include <linux/time64.h> +#include <linux/timekeeping.h> +#include <linux/timekeeper_internal.h> #include <linux/mm.h> @@ -79,6 +84,83 @@ int xen_unmap_domain_gfn_range(struct vm_area_struct *vma, } EXPORT_SYMBOL_GPL(xen_unmap_domain_gfn_range); +static unsigned long long xen_stolen_accounting(int cpu) +{ + struct vcpu_runstate_info state; + + BUG_ON(cpu != smp_processor_id()); + + xen_get_runstate_snapshot(&state); + + WARN_ON(state.state != RUNSTATE_running); + + return state.time[RUNSTATE_runnable] + state.time[RUNSTATE_offline]; +} + +static void xen_read_wallclock(struct timespec64 *ts) +{ + u32 version; + struct timespec64 now, ts_monotonic; + struct shared_info *s = HYPERVISOR_shared_info; + struct pvclock_wall_clock *wall_clock = &(s->wc); + + /* get wallclock at system boot */ + do { + version = wall_clock->version; + rmb(); /* fetch version before time */ + now.tv_sec = ((uint64_t)wall_clock->sec_hi << 32) | wall_clock->sec; + now.tv_nsec = wall_clock->nsec; + rmb(); /* fetch time before checking version */ + } while ((wall_clock->version & 1) || (version != wall_clock->version)); + + /* time since system boot */ + ktime_get_ts64(&ts_monotonic); + *ts = timespec64_add(now, ts_monotonic); +} + +static int xen_pvclock_gtod_notify(struct notifier_block *nb, + unsigned long was_set, void *priv) +{ + /* Protected by the calling core code serialization */ + static struct timespec64 next_sync; + + struct xen_platform_op op; + struct timespec64 now, system_time; + struct timekeeper *tk = priv; + + now.tv_sec = tk->xtime_sec; + now.tv_nsec = (long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift); + system_time = timespec64_add(now, tk->wall_to_monotonic); + + /* + * We only take the expensive HV call when the clock was set + * or when the 11 minutes RTC synchronization time elapsed. + */ + if (!was_set && timespec64_compare(&now, &next_sync) < 0) + return NOTIFY_OK; + + op.cmd = XENPF_settime64; + op.u.settime64.mbz = 0; + op.u.settime64.secs = now.tv_sec; + op.u.settime64.nsecs = now.tv_nsec; + op.u.settime64.system_time = timespec64_to_ns(&system_time); + (void)HYPERVISOR_platform_op(&op); + + /* + * Move the next drift compensation time 11 minutes + * ahead. That's emulating the sync_cmos_clock() update for + * the hardware RTC. + */ + next_sync = now; + next_sync.tv_sec += 11 * 60; + + return NOTIFY_OK; +} + +static struct notifier_block xen_pvclock_gtod_notifier = { + .notifier_call = xen_pvclock_gtod_notify, +}; + static void xen_percpu_init(void) { struct vcpu_register_vcpu_info info; @@ -104,6 +186,8 @@ static void xen_percpu_init(void) BUG_ON(err); per_cpu(xen_vcpu, cpu) = vcpup; + xen_setup_runstate_info(cpu); + after_register_vcpu_info: enable_percpu_irq(xen_events_irq, 0); put_cpu(); @@ -271,6 +355,11 @@ static int __init xen_guest_init(void) register_cpu_notifier(&xen_cpu_notifier); + pv_time_ops.steal_clock = xen_stolen_accounting; + static_key_slow_inc(¶virt_steal_enabled); + if (xen_initial_domain()) + pvclock_gtod_register_notifier(&xen_pvclock_gtod_notifier); + return 0; } early_initcall(xen_guest_init); @@ -282,6 +371,11 @@ static int __init xen_pm_init(void) pm_power_off = xen_power_off; arm_pm_restart = xen_restart; + if (!xen_initial_domain()) { + struct timespec64 ts; + xen_read_wallclock(&ts); + do_settimeofday64(&ts); + } return 0; } @@ -307,5 +401,6 @@ EXPORT_SYMBOL_GPL(HYPERVISOR_memory_op); EXPORT_SYMBOL_GPL(HYPERVISOR_physdev_op); EXPORT_SYMBOL_GPL(HYPERVISOR_vcpu_op); EXPORT_SYMBOL_GPL(HYPERVISOR_tmem_op); +EXPORT_SYMBOL_GPL(HYPERVISOR_platform_op); EXPORT_SYMBOL_GPL(HYPERVISOR_multicall); EXPORT_SYMBOL_GPL(privcmd_call); diff --git a/arch/arm/xen/hypercall.S b/arch/arm/xen/hypercall.S index 10fd99c568c6..9a36f4f49c10 100644 --- a/arch/arm/xen/hypercall.S +++ b/arch/arm/xen/hypercall.S @@ -89,6 +89,7 @@ HYPERCALL2(memory_op); HYPERCALL2(physdev_op); HYPERCALL3(vcpu_op); HYPERCALL1(tmem_op); +HYPERCALL1(platform_op_raw); HYPERCALL2(multicall); ENTRY(privcmd_call) |