From: Dapeng Mi <[email protected]> MSR_CORE_PERF_GLOBAL_OVF_CTRL is a write-only MSR and reads always return zero.
Saving and restoring this MSR is therefore unnecessary. Replace VMSTATE_UINT64 with VMSTATE_UNUSED in the VMStateDescription to ignore env.msr_global_ovf_ctrl during migration. This avoids the need to bump version_id and does not introduce any migration incompatibility. Signed-off-by: Dapeng Mi <[email protected]> Signed-off-by: Zide Chen <[email protected]> --- target/i386/cpu.h | 1 - target/i386/kvm/kvm.c | 6 ------ target/i386/machine.c | 4 ++-- 3 files changed, 2 insertions(+), 9 deletions(-) diff --git a/target/i386/cpu.h b/target/i386/cpu.h index f2b79a8bf1dc..0b480c631ed0 100644 --- a/target/i386/cpu.h +++ b/target/i386/cpu.h @@ -2086,7 +2086,6 @@ typedef struct CPUArchState { uint64_t msr_fixed_ctr_ctrl; uint64_t msr_global_ctrl; uint64_t msr_global_status; - uint64_t msr_global_ovf_ctrl; uint64_t msr_fixed_counters[MAX_FIXED_COUNTERS]; uint64_t msr_gp_counters[MAX_GP_COUNTERS]; uint64_t msr_gp_evtsel[MAX_GP_COUNTERS]; diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c index 7b9b740a8e5a..cffbc90d1c50 100644 --- a/target/i386/kvm/kvm.c +++ b/target/i386/kvm/kvm.c @@ -4069,8 +4069,6 @@ static int kvm_put_msrs(X86CPU *cpu, KvmPutState level) if (has_architectural_pmu_version > 1) { kvm_msr_entry_add(cpu, MSR_CORE_PERF_GLOBAL_STATUS, env->msr_global_status); - kvm_msr_entry_add(cpu, MSR_CORE_PERF_GLOBAL_OVF_CTRL, - env->msr_global_ovf_ctrl); /* Now start the PMU. */ kvm_msr_entry_add(cpu, MSR_CORE_PERF_FIXED_CTR_CTRL, @@ -4588,7 +4586,6 @@ static int kvm_get_msrs(X86CPU *cpu) kvm_msr_entry_add(cpu, MSR_CORE_PERF_FIXED_CTR_CTRL, 0); kvm_msr_entry_add(cpu, MSR_CORE_PERF_GLOBAL_CTRL, 0); kvm_msr_entry_add(cpu, MSR_CORE_PERF_GLOBAL_STATUS, 0); - kvm_msr_entry_add(cpu, MSR_CORE_PERF_GLOBAL_OVF_CTRL, 0); } for (i = 0; i < num_architectural_pmu_fixed_counters; i++) { kvm_msr_entry_add(cpu, MSR_CORE_PERF_FIXED_CTR0 + i, 0); @@ -4917,9 +4914,6 @@ static int kvm_get_msrs(X86CPU *cpu) case MSR_CORE_PERF_GLOBAL_STATUS: env->msr_global_status = msrs[i].data; break; - case MSR_CORE_PERF_GLOBAL_OVF_CTRL: - env->msr_global_ovf_ctrl = msrs[i].data; - break; case MSR_CORE_PERF_FIXED_CTR0 ... MSR_CORE_PERF_FIXED_CTR0 + MAX_FIXED_COUNTERS - 1: env->msr_fixed_counters[index - MSR_CORE_PERF_FIXED_CTR0] = msrs[i].data; break; diff --git a/target/i386/machine.c b/target/i386/machine.c index c9139612813b..1125c8a64ec5 100644 --- a/target/i386/machine.c +++ b/target/i386/machine.c @@ -666,7 +666,7 @@ static bool pmu_enable_needed(void *opaque) int i; if (env->msr_fixed_ctr_ctrl || env->msr_global_ctrl || - env->msr_global_status || env->msr_global_ovf_ctrl) { + env->msr_global_status) { return true; } for (i = 0; i < MAX_FIXED_COUNTERS; i++) { @@ -692,7 +692,7 @@ static const VMStateDescription vmstate_msr_architectural_pmu = { VMSTATE_UINT64(env.msr_fixed_ctr_ctrl, X86CPU), VMSTATE_UINT64(env.msr_global_ctrl, X86CPU), VMSTATE_UINT64(env.msr_global_status, X86CPU), - VMSTATE_UINT64(env.msr_global_ovf_ctrl, X86CPU), + VMSTATE_UNUSED(sizeof(uint64_t)), VMSTATE_UINT64_ARRAY(env.msr_fixed_counters, X86CPU, MAX_FIXED_COUNTERS), VMSTATE_UINT64_ARRAY(env.msr_gp_counters, X86CPU, MAX_GP_COUNTERS), VMSTATE_UINT64_ARRAY(env.msr_gp_evtsel, X86CPU, MAX_GP_COUNTERS), -- 2.52.0
