[PATCH 15/21] qemu-kvm: Clean up mpstate synchronization

Jan Kiszka
2010-02-02T08:19:35Z

Push mpstate reading/writing into kvm_arch_load/save_regs and, on x86,
properly synchronize with halted in the accessor functions.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---
hw/apic.c | 7 ----
qemu-kvm-ia64.c | 4 ++-
qemu-kvm-x86.c | 88 +++++++++++++++++++++++++++---------------------
qemu-kvm.c | 30 -----------------
qemu-kvm.h | 15 --------
target-i386/machine.c | 6 ---
target-ia64/machine.c | 3 ++
7 files changed, 55 insertions(+), 98 deletions(-)

diff --git a/hw/apic.c b/hw/apic.c
index 3e03e10..092c61e 100644
--- a/hw/apic.c
+++ b/hw/apic.c
@@ -507,13 +507,6 @@ void apic_init_reset(CPUState *env)
s->wait_for_sipi = 1;

env->halted = !(s->apicbase & MSR_IA32_APICBASE_BSP);
-#ifdef KVM_CAP_MP_STATE
- if (kvm_enabled() && kvm_irqchip_in_kernel()) {
- env->mp_state
- = env->halted ? KVM_MP_STATE_UNINITIALIZED : KVM_MP_STATE_RUNNABLE;
- kvm_load_mpstate(env);
- }
-#endif
}

static void apic_startup(APICState *s, int vector_num)
diff --git a/qemu-kvm-ia64.c b/qemu-kvm-ia64.c
index fc8110e..39bcbeb 100644
--- a/qemu-kvm-ia64.c
+++ b/qemu-kvm-ia64.c
@@ -124,7 +124,9 @@ void kvm_arch_cpu_reset(CPUState *env)
{
if (kvm_irqchip_in_kernel(kvm_context)) {
#ifdef KVM_CAP_MP_STATE
- kvm_reset_mpstate(env->kvm_cpu_state.vcpu_ctx);
+ struct kvm_mp_state mp_state = {.mp_state = KVM_MP_STATE_UNINITIALIZED
+ };
+ kvm_set_mpstate(env, &mp_state);
#endif
} else {
env->interrupt_request &= ~CPU_INTERRUPT_HARD;
diff --git a/qemu-kvm-x86.c b/qemu-kvm-x86.c
index 63cd095..6b5895f 100644
--- a/qemu-kvm-x86.c
+++ b/qemu-kvm-x86.c
@@ -754,6 +754,48 @@ static int get_msr_entry(struct kvm_msr_entry *entry, CPUState *env)
return 0;
}

+static void kvm_arch_save_mpstate(CPUState *env)
+{
+#ifdef KVM_CAP_MP_STATE
+ int r;
+ struct kvm_mp_state mp_state;
+
+ r = kvm_get_mpstate(env, &mp_state);
+ if (r < 0) {
+ env->mp_state = -1;
+ } else {
+ env->mp_state = mp_state.mp_state;
+ if (kvm_irqchip_in_kernel()) {
+ env->halted = (env->mp_state == KVM_MP_STATE_HALTED);
+ }
+ }
+#else
+ env->mp_state = -1;
+#endif
+}
+
+static void kvm_arch_load_mpstate(CPUState *env)
+{
+#ifdef KVM_CAP_MP_STATE
+ struct kvm_mp_state mp_state;
+
+ /*
+ * -1 indicates that the host did not support GET_MP_STATE ioctl,
+ * so don't touch it.
+ */
+ if (env->mp_state != -1) {
+ if (kvm_irqchip_in_kernel()) {
+ env->mp_state = env->halted ? KVM_MP_STATE_UNINITIALIZED :
+ KVM_MP_STATE_RUNNABLE;
+ /* Avoid deadlock: no user space IRQ will ever clear it. */
+ env->halted = 0;
+ }
+ mp_state.mp_state = env->mp_state;
+ kvm_set_mpstate(env, &mp_state);
+ }
+#endif
+}
+
static void set_v8086_seg(struct kvm_segment *lhs, const SegmentCache *rhs)
{
lhs->selector = rhs->selector;
@@ -926,6 +968,10 @@ void kvm_arch_load_regs(CPUState *env, int level)
rc = kvm_set_msrs(env, msrs, n);
if (rc == -1)
perror("kvm_set_msrs FAILED");
+
+ if (level >= KVM_PUT_RESET_STATE) {
+ kvm_arch_load_mpstate(env);
+ }
}

void kvm_load_tsc(CPUState *env)
@@ -940,36 +986,6 @@ void kvm_load_tsc(CPUState *env)
perror("kvm_set_tsc FAILED.\n");
}

-void kvm_arch_save_mpstate(CPUState *env)
-{
-#ifdef KVM_CAP_MP_STATE
- int r;
- struct kvm_mp_state mp_state;
-
- r = kvm_get_mpstate(env, &mp_state);
- if (r < 0)
- env->mp_state = -1;
- else
- env->mp_state = mp_state.mp_state;
-#else
- env->mp_state = -1;
-#endif
-}
-
-void kvm_arch_load_mpstate(CPUState *env)
-{
-#ifdef KVM_CAP_MP_STATE
- struct kvm_mp_state mp_state = { .mp_state = env->mp_state };
-
- /*
- * -1 indicates that the host did not support GET_MP_STATE ioctl,
- * so don't touch it.
- */
- if (env->mp_state != -1)
- kvm_set_mpstate(env, &mp_state);
-#endif
-}
-
void kvm_arch_save_regs(CPUState *env)
{
struct kvm_regs regs;
@@ -1366,15 +1382,9 @@ void kvm_arch_cpu_reset(CPUState *env)
{
kvm_arch_reset_vcpu(env);
kvm_put_vcpu_events(env);
- if (!cpu_is_bsp(env)) {
- if (kvm_irqchip_in_kernel()) {
-#ifdef KVM_CAP_MP_STATE
- kvm_reset_mpstate(env);
-#endif
- } else {
- env->interrupt_request &= ~CPU_INTERRUPT_HARD;
- env->halted = 1;
- }
+ if (!cpu_is_bsp(env) && !kvm_irqchip_in_kernel()) {
+ env->interrupt_request &= ~CPU_INTERRUPT_HARD;
+ env->halted = 1;
}
}

diff --git a/qemu-kvm.c b/qemu-kvm.c
index 53030f1..efa6a29 100644
--- a/qemu-kvm.c
+++ b/qemu-kvm.c
@@ -1579,36 +1579,6 @@ void kvm_update_interrupt_request(CPUState *env)
}
}

-static void kvm_do_load_mpstate(void *_env)
-{
- CPUState *env = _env;
-
- kvm_arch_load_mpstate(env);
-}
-
-void kvm_load_mpstate(CPUState *env)
-{
- if (kvm_enabled() && qemu_system_ready && kvm_vcpu_inited(env))
- on_vcpu(env, kvm_do_load_mpstate, env);
-}
-
-static void kvm_do_save_mpstate(void *_env)
-{
- CPUState *env = _env;
-
- kvm_arch_save_mpstate(env);
-#ifdef KVM_CAP_MP_STATE
- if (kvm_irqchip_in_kernel())
- env->halted = (env->mp_state == KVM_MP_STATE_HALTED);
-#endif
-}
-
-void kvm_save_mpstate(CPUState *env)
-{
- if (kvm_enabled())
- on_vcpu(env, kvm_do_save_mpstate, env);
-}
-
int kvm_cpu_exec(CPUState *env)
{
int r;
diff --git a/qemu-kvm.h b/qemu-kvm.h
index 6d785a0..aa7bcce 100644
--- a/qemu-kvm.h
+++ b/qemu-kvm.h
@@ -299,16 +299,6 @@ int kvm_get_mpstate(CPUState *env, struct kvm_mp_state *mp_state);
*
*/
int kvm_set_mpstate(CPUState *env, struct kvm_mp_state *mp_state);
-/*!
- * * \brief Reset VCPU MP state
- *
- */
-static inline int kvm_reset_mpstate(CPUState *env)
-{
- struct kvm_mp_state mp_state = {.mp_state = KVM_MP_STATE_UNINITIALIZED
- };
- return kvm_set_mpstate(env, &mp_state);
-}
#endif

/*!
@@ -874,8 +864,6 @@ static inline void kvm_inject_x86_mce(CPUState *cenv, int bank,
int kvm_main_loop(void);
int kvm_init_ap(void);
int kvm_vcpu_inited(CPUState *env);
-void kvm_load_mpstate(CPUState *env);
-void kvm_save_mpstate(CPUState *env);
void kvm_apic_init(CPUState *env);
/* called from vcpu initialization */
void qemu_kvm_load_lapic(CPUState *env);
@@ -909,8 +897,6 @@ int kvm_arch_qemu_create_context(void);

void kvm_arch_save_regs(CPUState *env);
void kvm_arch_load_regs(CPUState *env, int level);
-void kvm_arch_load_mpstate(CPUState *env);
-void kvm_arch_save_mpstate(CPUState *env);
int kvm_arch_has_work(CPUState *env);
void kvm_arch_process_irqchip_events(CPUState *env);
int kvm_arch_try_push_interrupts(void *opaque);
@@ -979,7 +965,6 @@ void kvm_load_tsc(CPUState *env);
#ifdef TARGET_I386
#define qemu_kvm_has_pit_state2() (0)
#endif
-#define kvm_save_mpstate(env) do {} while(0)
#define qemu_kvm_cpu_stop(env) do {} while(0)
static inline void kvm_load_tsc(CPUState *env)
{
diff --git a/target-i386/machine.c b/target-i386/machine.c
index bebde82..61e6a87 100644
--- a/target-i386/machine.c
+++ b/target-i386/machine.c
@@ -323,7 +323,6 @@ static void cpu_pre_save(void *opaque)
int i;

if (kvm_enabled()) {
- kvm_save_mpstate(env);
kvm_get_vcpu_events(env);
}

@@ -362,12 +361,7 @@ static int cpu_post_load(void *opaque, int version_id)
tlb_flush(env, 1);

if (kvm_enabled()) {
- /* when in-kernel irqchip is used, env->halted causes deadlock
- because no userspace IRQs will ever clear this flag */
- env->halted = 0;
-
kvm_load_tsc(env);
- kvm_load_mpstate(env);
kvm_put_vcpu_events(env);
}

diff --git a/target-ia64/machine.c b/target-ia64/machine.c
index fdbeeef..8cf5bdd 100644
--- a/target-ia64/machine.c
+++ b/target-ia64/machine.c
@@ -4,6 +4,9 @@
#include "exec-all.h"
#include "qemu-kvm.h"

+void kvm_arch_save_mpstate(CPUState *env);
+void kvm_arch_load_mpstate(CPUState *env);
+
void cpu_save(QEMUFile *f, void *opaque)
{
CPUState *env = opaque;
--
1.6.0.2