Kernel/linux-next
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git synced 2025-01-15 10:27:53 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

arm/xen: Convert to hotplug state machine

Browse Source 
Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.

The get_cpu() in xen_starting_cpu() boils down to preempt_disable() since
we already know the CPU we run on. Disabling preemption shouldn't be required
here from what I see since it we don't switch CPUs while invoking the function.

Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: rt@linutronix.de
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/20160713153336.971559670@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Richard Cochran 2016-07-13 17:16:52 +00:00 committed by Ingo Molnar
parent 26b8768868
commit 4761adb6f4
2 changed files with 12 additions and 30 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

41
arch/arm/xen/enlighten.c
View File

@ -161,12 +161,11 @@ static struct notifier_block xen_pvclock_gtod_notifier = {
.notifier_call = xen_pvclock_gtod_notify,
};
static void xen_percpu_init(void)
static int xen_starting_cpu(unsigned int cpu)
{
struct vcpu_register_vcpu_info info;
struct vcpu_info *vcpup;
int err;
int cpu = get_cpu();
/*
* VCPUOP_register_vcpu_info cannot be called twice for the same
@ -190,7 +189,13 @@ static void xen_percpu_init(void)
after_register_vcpu_info:
enable_percpu_irq(xen_events_irq, 0);
put_cpu();
return 0;
}
static int xen_dying_cpu(unsigned int cpu)
{
disable_percpu_irq(xen_events_irq);
return 0;
}
static void xen_restart(enum reboot_mode reboot_mode, const char *cmd)
@ -209,28 +214,6 @@ static void xen_power_off(void)
BUG_ON(rc);
}
static int xen_cpu_notification(struct notifier_block *self,
unsigned long action,
void *hcpu)
{
switch (action) {
case CPU_STARTING:
xen_percpu_init();
break;
case CPU_DYING:
disable_percpu_irq(xen_events_irq);
break;
default:
break;
}
return NOTIFY_OK;
}
static struct notifier_block xen_cpu_notifier = {
.notifier_call = xen_cpu_notification,
};
static irqreturn_t xen_arm_callback(int irq, void *arg)
{
xen_hvm_evtchn_do_upcall();
@ -351,16 +334,14 @@ static int __init xen_guest_init(void)
return -EINVAL;
}
xen_percpu_init();
register_cpu_notifier(&xen_cpu_notifier);
pv_time_ops.steal_clock = xen_stolen_accounting;
static_key_slow_inc(&paravirt_steal_enabled);
if (xen_initial_domain())
pvclock_gtod_register_notifier(&xen_pvclock_gtod_notifier);
return 0;
return cpuhp_setup_state(CPUHP_AP_ARM_XEN_STARTING,
"AP_ARM_XEN_STARTING", xen_starting_cpu,
xen_dying_cpu);
}
early_initcall(xen_guest_init);

1
include/linux/cpuhotplug.h
View File

@ -47,6 +47,7 @@ enum cpuhp_state {
CPUHP_AP_KVM_STARTING,
CPUHP_AP_KVM_ARM_VGIC_STARTING,
CPUHP_AP_KVM_ARM_TIMER_STARTING,
CPUHP_AP_ARM_XEN_STARTING,
CPUHP_AP_LEDTRIG_STARTING,
CPUHP_AP_NOTIFY_STARTING,
CPUHP_AP_ONLINE,