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authorGleb Natapov <gleb@redhat.com>2010-10-14 11:22:51 +0200
committerAvi Kivity <avi@redhat.com>2011-01-12 11:23:14 +0200
commitfd10cde9294f73eeccbc16f3fec1ae6cde7b800c (patch)
tree6d49e440289c783ff1d5c635c57acd07a6b9c147 /arch/x86/kernel
parent344d9588a9df06182684168be4f1408b55c7da3e (diff)
KVM paravirt: Add async PF initialization to PV guest.
Enable async PF in a guest if async PF capability is discovered. Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Diffstat (limited to 'arch/x86/kernel')
-rw-r--r--arch/x86/kernel/kvm.c92
1 files changed, 92 insertions, 0 deletions
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index e6db17976b8..032d03b6b54 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -27,16 +27,30 @@
#include <linux/mm.h>
#include <linux/highmem.h>
#include <linux/hardirq.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
#include <asm/timer.h>
+#include <asm/cpu.h>
#define MMU_QUEUE_SIZE 1024
+static int kvmapf = 1;
+
+static int parse_no_kvmapf(char *arg)
+{
+ kvmapf = 0;
+ return 0;
+}
+
+early_param("no-kvmapf", parse_no_kvmapf);
+
struct kvm_para_state {
u8 mmu_queue[MMU_QUEUE_SIZE];
int mmu_queue_len;
};
static DEFINE_PER_CPU(struct kvm_para_state, para_state);
+static DEFINE_PER_CPU(struct kvm_vcpu_pv_apf_data, apf_reason) __aligned(64);
static struct kvm_para_state *kvm_para_state(void)
{
@@ -231,12 +245,86 @@ static void __init paravirt_ops_setup(void)
#endif
}
+void __cpuinit kvm_guest_cpu_init(void)
+{
+ if (!kvm_para_available())
+ return;
+
+ if (kvm_para_has_feature(KVM_FEATURE_ASYNC_PF) && kvmapf) {
+ u64 pa = __pa(&__get_cpu_var(apf_reason));
+
+ wrmsrl(MSR_KVM_ASYNC_PF_EN, pa | KVM_ASYNC_PF_ENABLED);
+ __get_cpu_var(apf_reason).enabled = 1;
+ printk(KERN_INFO"KVM setup async PF for cpu %d\n",
+ smp_processor_id());
+ }
+}
+
+static void kvm_pv_disable_apf(void *unused)
+{
+ if (!__get_cpu_var(apf_reason).enabled)
+ return;
+
+ wrmsrl(MSR_KVM_ASYNC_PF_EN, 0);
+ __get_cpu_var(apf_reason).enabled = 0;
+
+ printk(KERN_INFO"Unregister pv shared memory for cpu %d\n",
+ smp_processor_id());
+}
+
+static int kvm_pv_reboot_notify(struct notifier_block *nb,
+ unsigned long code, void *unused)
+{
+ if (code == SYS_RESTART)
+ on_each_cpu(kvm_pv_disable_apf, NULL, 1);
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block kvm_pv_reboot_nb = {
+ .notifier_call = kvm_pv_reboot_notify,
+};
+
#ifdef CONFIG_SMP
static void __init kvm_smp_prepare_boot_cpu(void)
{
WARN_ON(kvm_register_clock("primary cpu clock"));
+ kvm_guest_cpu_init();
native_smp_prepare_boot_cpu();
}
+
+static void kvm_guest_cpu_online(void *dummy)
+{
+ kvm_guest_cpu_init();
+}
+
+static void kvm_guest_cpu_offline(void *dummy)
+{
+ kvm_pv_disable_apf(NULL);
+}
+
+static int __cpuinit kvm_cpu_notify(struct notifier_block *self,
+ unsigned long action, void *hcpu)
+{
+ int cpu = (unsigned long)hcpu;
+ switch (action) {
+ case CPU_ONLINE:
+ case CPU_DOWN_FAILED:
+ case CPU_ONLINE_FROZEN:
+ smp_call_function_single(cpu, kvm_guest_cpu_online, NULL, 0);
+ break;
+ case CPU_DOWN_PREPARE:
+ case CPU_DOWN_PREPARE_FROZEN:
+ smp_call_function_single(cpu, kvm_guest_cpu_offline, NULL, 1);
+ break;
+ default:
+ break;
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block __cpuinitdata kvm_cpu_notifier = {
+ .notifier_call = kvm_cpu_notify,
+};
#endif
void __init kvm_guest_init(void)
@@ -245,7 +333,11 @@ void __init kvm_guest_init(void)
return;
paravirt_ops_setup();
+ register_reboot_notifier(&kvm_pv_reboot_nb);
#ifdef CONFIG_SMP
smp_ops.smp_prepare_boot_cpu = kvm_smp_prepare_boot_cpu;
+ register_cpu_notifier(&kvm_cpu_notifier);
+#else
+ kvm_guest_cpu_init();
#endif
}