KVM Paravirt clock - take2

274 lines not on this page · raw message

index 6a80d67..fa5d894 100644
@@ -20,6 +20,7 @@
 #include <linux/efi.h>
 #include <linux/bcd.h>
 #include <linux/highmem.h>
+#include <linux/kvm_para.h>
 
 #include <asm/bug.h>
 #include <asm/paravirt.h>

@@ -50,6 +51,13 @@ char *memory_setup(void)
 	return pv_init_ops.memory_setup();
 }
 
+static void paravirt_init_special_features(void)
+{
+#ifdef CONFIG_KVM_CLOCK
+	kvmclock_init();
+#endif
+}
+
 /* Simple instruction patching code. */
 #define DEF_NATIVE(ops, name, code)					\
 	extern const char start_##ops##_##name[], end_##ops##_##name[];	\

@@ -334,7 +342,7 @@ struct pv_info pv_info = {
 struct pv_init_ops pv_init_ops = {
 	.patch = native_patch,
 	.banner = default_banner,
-	.arch_setup = paravirt_nop,
+	.arch_setup = paravirt_init_special_features,
 	.memory_setup = machine_specific_memory_setup,
 };
 

index cc0e914..f833395 100644
@@ -546,6 +546,7 @@ void __init setup_arch(char **cmdline_p)
 	unsigned long max_low_pfn;
 
 	memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
+	parse_early_param();
 	pre_setup_arch_hook();
 	early_cpu_init();
 

@@ -605,8 +606,6 @@ void __init setup_arch(char **cmdline_p)
 	bss_resource.start = virt_to_phys(&__bss_start);
 	bss_resource.end = virt_to_phys(&__bss_stop)-1;
 
-	parse_early_param();
-
 	if (user_defined_memmap) {
 		printk(KERN_INFO "user-defined physical RAM map:\n");
 		print_memory_map("user");

index 22bfeee..fe30099 100644
@@ -33,6 +33,8 @@ int kvm_cpu_has_interrupt(struct kvm_vcpu *v)
 {
 	struct kvm_pic *s;
 
+	if (v->timer_vector != -1)
+		return 1;
 	if (kvm_apic_has_interrupt(v) == -1) {	/* LAPIC */
 		if (kvm_apic_accept_pic_intr(v)) {
 			s = pic_irqchip(v->kvm);	/* PIC */

@@ -44,6 +46,12 @@ int kvm_cpu_has_interrupt(struct kvm_vcpu *v)
 }
 EXPORT_SYMBOL_GPL(kvm_cpu_has_interrupt);
 
+static int kvm_get_pvclock_interrupt(struct kvm_vcpu *v)
+{
+	int ret = v->timer_vector;
+	v->timer_vector = -1;
+	return	ret;
+}
 /*
  * Read pending interrupt vector and intack.
  */

@@ -52,7 +60,9 @@ int kvm_cpu_get_interrupt(struct kvm_vcpu *v)
 	struct kvm_pic *s;
 	int vector;
 
-	vector = kvm_get_apic_interrupt(v);	/* APIC */
+	vector = kvm_get_pvclock_interrupt(v);
+	if (vector == -1)
+		vector = kvm_get_apic_interrupt(v);	/* APIC */
 	if (vector == -1) {
 		if (kvm_apic_accept_pic_intr(v)) {
 			s = pic_irqchip(v->kvm);

index 08b5b21..3d2158c 100644
@@ -362,6 +362,10 @@ struct kvm {
 	struct kvm_mem_alias aliases[KVM_ALIAS_SLOTS];
 	int nmemslots;
 	struct kvm_memory_slot memslots[KVM_MEMORY_SLOTS];
+
+	struct page *clock_page;
+	u64 clock_gpa;
+	int time_needs_update;
 	/*
 	 * Hash table of struct kvm_mmu_page.
 	 */

140 lines not on this page · raw message

index 01452b5..27c65bc 100644
@@ -83,6 +83,9 @@ struct kvm_vcpu {
 	/* emulate context */
 
 	struct x86_emulate_ctxt emulate_ctxt;
+	struct hrtimer oneshooter;
+	int timer_vector;
+
 };
 
 static inline int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t gva,

index c6f3fd8..8dec29f 100644
@@ -10,9 +10,12 @@
  * paravirtualization, the appropriate feature bit should be checked.
  */
 #define KVM_CPUID_FEATURES	0x40000001
+#define KVM_FEATURE_CLOCKEVENTS 0
+#define KVM_FEATURE_CLOCKSOURCE 1
 
 #ifdef __KERNEL__
 #include <asm/processor.h>
+extern void kvmclock_init(void);
 
 /* This instruction is vmcall.  On non-VT architectures, it will generate a
  * trap that we will then rewrite to the appropriate instruction.

@@ -29,6 +32,26 @@
  * noted by the particular hypercall.
  */
 
+#define KVM_HCALL_REGISTER_CLOCK 0
+#define KVM_HCALL_SET_ALARM	1
+#define KVM_HCALL_STOP_ONESHOT 2
+
+struct kvm_hv_clock {
+	u64 tsc_mult;
+	u64 now_ns;
+	/* That's the wall clock, not the water closet */
+	u64 wc_sec;
+	u64 wc_nsec;
+	u64 last_tsc;
+	/* 
+	 * At first, we could use the tsc value as a marker, but Jeremy
+	 * well noted that it will cause us locking problems in 32-bit sys,
+	 * so we have a special version field
+	 */
+	u32 version;
+	u32 stable_tsc; /* use raw tsc for clock_read */
+};
+
 static inline long kvm_hypercall0(unsigned int nr)
 {
 	long ret;

index e4db25f..4c2afd0 100644
@@ -9,6 +9,10 @@
  * - kvm_para_available
  */
 
+#define KVM_CPUID_FEATURES	0x40000001
+#define KVM_FEATURE_CLOCKEVENTS 0
+#define KVM_FEATURE_CLOCKSOURCE 1
+
 /* Return values for hypercalls */
 #define KVM_ENOSYS		1000