kvm: reset state from the CPU's reset method

Now that we have a CPU object with a reset method, it is better to
keep the KVM reset close to the CPU reset.  Using qemu_register_reset
as we do now keeps them far apart.

With this patch, PPC no longer calls the kvm_arch_ function, so
it can get removed there.  Other arches call it from their CPU
reset handler, and the function gets an ARMCPU/X86CPU/S390CPU.

Note that ARM- and s390-specific functions are called kvm_arm_*
and kvm_s390_*, while x86-specific functions are called kvm_arch_*.
That follows the convention used by the different architectures.
Changing that is the topic of a separate patch.

Reviewed-by: Gleb Natapov <gnatapov@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

include/sysemu/kvm.h

@@ -245,8 +245,6 @@ int kvm_arch_init_vcpu(CPUState *cpu);
 /* Returns VCPU ID to be used on KVM_CREATE_VCPU ioctl() */
 unsigned long kvm_arch_vcpu_id(CPUState *cpu);
 
-void kvm_arch_reset_vcpu(CPUState *cpu);
-
 int kvm_arch_on_sigbus_vcpu(CPUState *cpu, int code, void *addr);
 int kvm_arch_on_sigbus(int code, void *addr);
 

kvm-all.c

@@ -223,13 +223,6 @@ static int kvm_set_user_memory_region(KVMState *s, KVMSlot *slot)
     return kvm_vm_ioctl(s, KVM_SET_USER_MEMORY_REGION, &mem);
 }
 
-static void kvm_reset_vcpu(void *opaque)
-{
-    CPUState *cpu = opaque;
-
-    kvm_arch_reset_vcpu(cpu);
-}
-
 int kvm_init_vcpu(CPUState *cpu)
 {
     KVMState *s = kvm_state;
@@ -269,10 +262,6 @@ int kvm_init_vcpu(CPUState *cpu)
     }
 
     ret = kvm_arch_init_vcpu(cpu);
-    if (ret == 0) {
-        qemu_register_reset(kvm_reset_vcpu, cpu);
-        kvm_arch_reset_vcpu(cpu);
-    }
 err:
     return ret;
 }

target-arm/cpu.c

@@ -29,6 +29,7 @@
 #include "hw/arm/arm.h"
 #include "sysemu/sysemu.h"
 #include "sysemu/kvm.h"
+#include "kvm_arm.h"
 
 static void arm_cpu_set_pc(CPUState *cs, vaddr value)
 {
@@ -165,6 +166,12 @@ static void arm_cpu_reset(CPUState *s)
      * tb_flush().
      */
     tb_flush(env);
+
+#ifndef CONFIG_USER_ONLY
+    if (kvm_enabled()) {
+        kvm_arm_reset_vcpu(cpu);
+    }
+#endif
 }
 
 #ifndef CONFIG_USER_ONLY

target-arm/kvm32.c

@@ -510,11 +510,9 @@ int kvm_arch_get_registers(CPUState *cs)
     return 0;
 }
 
-void kvm_arch_reset_vcpu(CPUState *cs)
+void kvm_arm_reset_vcpu(ARMCPU *cpu)
 {
     /* Feed the kernel back its initial register state */
-    ARMCPU *cpu = ARM_CPU(cs);
-
     memmove(cpu->cpreg_values, cpu->cpreg_reset_values,
             cpu->cpreg_array_len * sizeof(cpu->cpreg_values[0]));
 

target-arm/kvm64.c

@@ -260,6 +260,6 @@ int kvm_arch_get_registers(CPUState *cs)
     return ret;
 }
 
-void kvm_arch_reset_vcpu(CPUState *cs)
+void kvm_arm_reset_vcpu(ARMCPU *cpu)
 {
 }

target-arm/kvm_arm.h

@@ -67,6 +67,14 @@ bool write_list_to_kvmstate(ARMCPU *cpu);
  */
 bool write_kvmstate_to_list(ARMCPU *cpu);
 
+/**
+ * kvm_arm_reset_vcpu:
+ * @cpu: ARMCPU
+ *
+ * Called at reset time to kernel registers to their initial values.
+ */
+void kvm_arm_reset_vcpu(ARMCPU *cpu);
+
 #ifdef CONFIG_KVM
 /**
  * kvm_arm_create_scratch_host_vcpu:

target-i386/cpu.c

@@ -24,6 +24,7 @@
 #include "cpu.h"
 #include "sysemu/kvm.h"
 #include "sysemu/cpus.h"
+#include "kvm_i386.h"
 #include "topology.h"
 
 #include "qemu/option.h"
@@ -2494,6 +2495,10 @@ static void x86_cpu_reset(CPUState *s)
     }
 
     s->halted = !cpu_is_bsp(cpu);
+
+    if (kvm_enabled()) {
+        kvm_arch_reset_vcpu(cpu);
+    }
 #endif
 }
 

target-i386/kvm.c

@@ -723,9 +723,8 @@ int kvm_arch_init_vcpu(CPUState *cs)
     return 0;
 }
 
-void kvm_arch_reset_vcpu(CPUState *cs)
+void kvm_arch_reset_vcpu(X86CPU *cpu)
 {
-    X86CPU *cpu = X86_CPU(cs);
     CPUX86State *env = &cpu->env;
 
     env->exception_injected = -1;

target-i386/kvm_i386.h

@@ -14,6 +14,7 @@
 #include "sysemu/kvm.h"
 
 bool kvm_allows_irq0_override(void);
+void kvm_arch_reset_vcpu(X86CPU *cs);
 
 int kvm_device_pci_assign(KVMState *s, PCIHostDeviceAddress *dev_addr,
                           uint32_t flags, uint32_t *dev_id);

target-ppc/kvm.c

@@ -430,10 +430,6 @@ int kvm_arch_init_vcpu(CPUState *cs)
     return ret;
 }
 
-void kvm_arch_reset_vcpu(CPUState *cpu)
-{
-}
-
 static void kvm_sw_tlb_put(PowerPCCPU *cpu)
 {
     CPUPPCState *env = &cpu->env;

target-s390x/cpu.c

@@ -152,6 +152,10 @@ static void s390_cpu_full_reset(CPUState *s)
      * after incrementing the cpu counter */
 #if !defined(CONFIG_USER_ONLY)
     s->halted = 1;
+
+    if (kvm_enabled()) {
+        kvm_s390_reset_vcpu(cpu);
+    }
 #endif
     tlb_flush(s, 1);
 }

target-s390x/cpu.h

@@ -359,11 +359,16 @@ void s390x_cpu_timer(void *opaque);
 int s390_virtio_hypercall(CPUS390XState *env);
 
 #ifdef CONFIG_KVM
+void kvm_s390_reset_vcpu(S390CPU *cpu);
 void kvm_s390_interrupt(S390CPU *cpu, int type, uint32_t code);
 void kvm_s390_virtio_irq(S390CPU *cpu, int config_change, uint64_t token);
 void kvm_s390_interrupt_internal(S390CPU *cpu, int type, uint32_t parm,
                                  uint64_t parm64, int vm);
 #else
+static inline void kvm_s390_reset_vcpu(S390CPU *cpu)
+{
+}
+
 static inline void kvm_s390_interrupt(S390CPU *cpu, int type, uint32_t code)
 {
 }

target-s390x/kvm.c

@@ -117,14 +117,16 @@ int kvm_arch_init_vcpu(CPUState *cpu)
     return 0;
 }
 
-void kvm_arch_reset_vcpu(CPUState *cpu)
+void kvm_s390_reset_vcpu(S390CPU *cpu)
 {
+    CPUState *cs = CPU(cpu);
+
     /* The initial reset call is needed here to reset in-kernel
      * vcpu data that we can't access directly from QEMU
      * (i.e. with older kernels which don't support sync_regs/ONE_REG).
      * Before this ioctl cpu_synchronize_state() is called in common kvm
      * code (kvm-all) */
-    if (kvm_vcpu_ioctl(cpu, KVM_S390_INITIAL_RESET, NULL)) {
+    if (kvm_vcpu_ioctl(cs, KVM_S390_INITIAL_RESET, NULL)) {
         perror("Can't reset vcpu\n");
     }
 }