Re: [PATCH v4 10/12] target/riscv: Add kvm_riscv_get/put_regs_timer

Add kvm_riscv_get/put_regs_timer to synchronize virtual time context from KVM. To set register of RISCV_TIMER_REG(state) will occur a error from KVM on kvm_timer_state == 0. It's better to adapt in KVM, but it doesn't matter that adaping in QEMU. Signed-off-by: Yifei Jiang <jiangyifei(a)huawei.com&gt; Signed-off-by: Mingwang Li <limingwang(a)huawei.com&gt; Reviewed-by: Anup Patel <anup.patel(a)wdc.com&gt;

--- target/riscv/cpu.h | 7 +++++ target/riscv/kvm.c | 72 ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 79 insertions(+) diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h index 5f54fae7cc..9eceded96c 100644 --- a/target/riscv/cpu.h +++ b/target/riscv/cpu.h @@ -261,6 +261,13 @@ struct CPURISCVState { hwaddr kernel_addr; hwaddr fdt_addr; + + /* kvm timer */ + bool kvm_timer_dirty; + uint64_t kvm_timer_time; + uint64_t kvm_timer_compare; + uint64_t kvm_timer_state; + uint64_t kvm_timer_frequency; }; OBJECT_DECLARE_TYPE(RISCVCPU, RISCVCPUClass, diff --git a/target/riscv/kvm.c b/target/riscv/kvm.c index ded2a8c29d..b1f1d55f29 100644 --- a/target/riscv/kvm.c +++ b/target/riscv/kvm.c @@ -40,6 +40,7 @@ #include "kvm_riscv.h" #include "sbi_ecall_interface.h" #include "chardev/char-fe.h" +#include "migration/migration.h" static uint64_t kvm_riscv_reg_id(CPURISCVState *env, uint64_t type, uint64_t idx) { @@ -64,6 +65,9 @@ static uint64_t kvm_riscv_reg_id(CPURISCVState *env, uint64_t type, uint64_t idx #define RISCV_CSR_REG(env, name) kvm_riscv_reg_id(env, KVM_REG_RISCV_CSR, \ KVM_REG_RISCV_CSR_REG(name)) +#define RISCV_TIMER_REG(env, name) kvm_riscv_reg_id(env, KVM_REG_RISCV_TIMER, \ + KVM_REG_RISCV_TIMER_REG(name)) + #define RISCV_FP_F_REG(env, idx) kvm_riscv_reg_id(env, KVM_REG_RISCV_FP_F, idx) #define RISCV_FP_D_REG(env, idx) kvm_riscv_reg_id(env, KVM_REG_RISCV_FP_D, idx) @@ -84,6 +88,22 @@ static uint64_t kvm_riscv_reg_id(CPURISCVState *env, uint64_t type, uint64_t idx } \ } while(0) +#define KVM_RISCV_GET_TIMER(cs, env, name, reg) \ + do { \ + int ret = kvm_get_one_reg(cs, RISCV_TIMER_REG(env, name), &reg); \ + if (ret) { \ + abort(); \ + } \ + } while(0) + +#define KVM_RISCV_SET_TIMER(cs, env, name, reg) \ + do { \ + int ret = kvm_set_one_reg(cs, RISCV_TIMER_REG(env, time), &reg); \ + if (ret) { \ + abort(); \ + } \ + } while (0) + static int kvm_riscv_get_regs_core(CPUState *cs) { int ret = 0; @@ -235,6 +255,58 @@ static int kvm_riscv_put_regs_fp(CPUState *cs) return ret; } +static void kvm_riscv_get_regs_timer(CPUState *cs) +{ + CPURISCVState *env = &RISCV_CPU(cs)->env; + + if (env->kvm_timer_dirty) { + return; + } + + KVM_RISCV_GET_TIMER(cs, env, time, env->kvm_timer_time); + KVM_RISCV_GET_TIMER(cs, env, compare, env->kvm_timer_compare); + KVM_RISCV_GET_TIMER(cs, env, state, env->kvm_timer_state); + KVM_RISCV_GET_TIMER(cs, env, frequency, env->kvm_timer_frequency); + + env->kvm_timer_dirty = true; +} + +static void kvm_riscv_put_regs_timer(CPUState *cs) +{ + uint64_t reg; + CPURISCVState *env = &RISCV_CPU(cs)->env; + + if (!env->kvm_timer_dirty) { + return; + } + + KVM_RISCV_SET_TIMER(cs, env, time, env->kvm_timer_time); + KVM_RISCV_SET_TIMER(cs, env, compare, env->kvm_timer_compare); + + /* + * To set register of RISCV_TIMER_REG(state) will occur a error from KVM + * on env->kvm_timer_state == 0, It's better to adapt in KVM, but it + * doesn't matter that adaping in QEMU now. + * TODO If KVM changes, adapt here. + */ + if (env->kvm_timer_state) { + KVM_RISCV_SET_TIMER(cs, env, state, env->kvm_timer_state); + } + + /* + * For now, migration will not work between Hosts with different timer + * frequency. Therefore, we should check whether they are the same here + * during the migration. + */ + if (migration_is_running(migrate_get_current()->state)) { + KVM_RISCV_GET_TIMER(cs, env, frequency, reg); + if (reg != env->kvm_timer_frequency) { + error_report("Dst Hosts timer frequency != Src Hosts"); + } + } + + env->kvm_timer_dirty = false; +} const KVMCapabilityInfo kvm_arch_required_capabilities[] = { KVM_CAP_LAST_INFO -- 2.19.1