diff options
| -rw-r--r-- | hw/ppc/ppc.c | 66 | ||||
| -rw-r--r-- | hw/ppc/spapr.c | 6 | ||||
| -rw-r--r-- | target/ppc/cpu-qom.h | 3 |
3 files changed, 52 insertions, 23 deletions
diff --git a/hw/ppc/ppc.c b/hw/ppc/ppc.c index f9a4b51d64..d171e60b5c 100644 --- a/hw/ppc/ppc.c +++ b/hw/ppc/ppc.c @@ -847,9 +847,8 @@ static void cpu_ppc_set_tb_clk (void *opaque, uint32_t freq) cpu_ppc_store_purr(cpu, 0x0000000000000000ULL); } -static void timebase_pre_save(void *opaque) +static void timebase_save(PPCTimebase *tb) { - PPCTimebase *tb = opaque; uint64_t ticks = cpu_get_host_ticks(); PowerPCCPU *first_ppc_cpu = POWERPC_CPU(first_cpu); @@ -858,43 +857,30 @@ static void timebase_pre_save(void *opaque) return; } + /* not used anymore, we keep it for compatibility */ tb->time_of_the_day_ns = qemu_clock_get_ns(QEMU_CLOCK_HOST); /* - * tb_offset is only expected to be changed by migration so + * tb_offset is only expected to be changed by QEMU so * there is no need to update it from KVM here */ tb->guest_timebase = ticks + first_ppc_cpu->env.tb_env->tb_offset; } -static int timebase_post_load(void *opaque, int version_id) +static void timebase_load(PPCTimebase *tb) { - PPCTimebase *tb_remote = opaque; CPUState *cpu; PowerPCCPU *first_ppc_cpu = POWERPC_CPU(first_cpu); - int64_t tb_off_adj, tb_off, ns_diff; - int64_t migration_duration_ns, migration_duration_tb, guest_tb, host_ns; + int64_t tb_off_adj, tb_off; unsigned long freq; if (!first_ppc_cpu->env.tb_env) { error_report("No timebase object"); - return -1; + return; } freq = first_ppc_cpu->env.tb_env->tb_freq; - /* - * Calculate timebase on the destination side of migration. - * The destination timebase must be not less than the source timebase. - * We try to adjust timebase by downtime if host clocks are not - * too much out of sync (1 second for now). - */ - host_ns = qemu_clock_get_ns(QEMU_CLOCK_HOST); - ns_diff = MAX(0, host_ns - tb_remote->time_of_the_day_ns); - migration_duration_ns = MIN(NANOSECONDS_PER_SECOND, ns_diff); - migration_duration_tb = muldiv64(freq, migration_duration_ns, - NANOSECONDS_PER_SECOND); - guest_tb = tb_remote->guest_timebase + MIN(0, migration_duration_tb); - tb_off_adj = guest_tb - cpu_get_host_ticks(); + tb_off_adj = tb->guest_timebase - cpu_get_host_ticks(); tb_off = first_ppc_cpu->env.tb_env->tb_offset; trace_ppc_tb_adjust(tb_off, tb_off_adj, tb_off_adj - tb_off, @@ -904,9 +890,44 @@ static int timebase_post_load(void *opaque, int version_id) CPU_FOREACH(cpu) { PowerPCCPU *pcpu = POWERPC_CPU(cpu); pcpu->env.tb_env->tb_offset = tb_off_adj; +#if defined(CONFIG_KVM) + kvm_set_one_reg(cpu, KVM_REG_PPC_TB_OFFSET, + &pcpu->env.tb_env->tb_offset); +#endif } +} - return 0; +void cpu_ppc_clock_vm_state_change(void *opaque, int running, + RunState state) +{ + PPCTimebase *tb = opaque; + + if (running) { + timebase_load(tb); + } else { + timebase_save(tb); + } +} + +/* + * When migrating, read the clock just before migration, + * so that the guest clock counts during the events + * between: + * + * * vm_stop() + * * + * * pre_save() + * + * This reduces clock difference on migration from 5s + * to 0.1s (when max_downtime == 5s), because sending the + * final pages of memory (which happens between vm_stop() + * and pre_save()) takes max_downtime. + */ +static void timebase_pre_save(void *opaque) +{ + PPCTimebase *tb = opaque; + + timebase_save(tb); } const VMStateDescription vmstate_ppc_timebase = { @@ -915,7 +936,6 @@ const VMStateDescription vmstate_ppc_timebase = { .minimum_version_id = 1, .minimum_version_id_old = 1, .pre_save = timebase_pre_save, - .post_load = timebase_post_load, .fields = (VMStateField []) { VMSTATE_UINT64(guest_timebase, PPCTimebase), VMSTATE_INT64(time_of_the_day_ns, PPCTimebase), diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index b71cd7aa43..9fc3fb90a1 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -2129,6 +2129,12 @@ static void ppc_spapr_init(MachineState *machine) qemu_register_reset(spapr_ccs_reset_hook, spapr); qemu_register_boot_set(spapr_boot_set, spapr); + + /* to stop and start vmclock */ + if (kvm_enabled()) { + qemu_add_vm_change_state_handler(cpu_ppc_clock_vm_state_change, + &spapr->tb); + } } static int spapr_kvm_type(const char *vm_type) diff --git a/target/ppc/cpu-qom.h b/target/ppc/cpu-qom.h index d46c31a15d..b7977bad18 100644 --- a/target/ppc/cpu-qom.h +++ b/target/ppc/cpu-qom.h @@ -214,6 +214,9 @@ extern const struct VMStateDescription vmstate_ppc_timebase; .flags = VMS_STRUCT, \ .offset = vmstate_offset_value(_state, _field, PPCTimebase), \ } + +void cpu_ppc_clock_vm_state_change(void *opaque, int running, + RunState state); #endif #endif |