On 19/11/2015 16:10, Matthew Rosato wrote:
> From: Bharata B Rao <bhar...@linux.vnet.ibm.com>
>
> This sync API will be used by the CPU hotplug code to wait for the CPU to
> completely get removed before flagging the failure to the device_add
> command.
>
> Sync version of this call is needed to correctly recover from CPU
> realization failures when ->plug() handler fails.
>
> Signed-off-by: Bharata B Rao <bhar...@linux.vnet.ibm.com>
> Signed-off-by: Matthew Rosato <mjros...@linux.vnet.ibm.com>
> [Call cpu_remove() directly from cpu_remove_sync()]
Are you using it in these patches?
Paolo
> ---
> cpus.c | 12 ++++++++++++
> include/qom/cpu.h | 8 ++++++++
> 2 files changed, 20 insertions(+)
>
> diff --git a/cpus.c b/cpus.c
> index af2b274..c2444ba 100644
> --- a/cpus.c
> +++ b/cpus.c
> @@ -1070,6 +1070,8 @@ static void *qemu_kvm_cpu_thread_fn(void *arg)
> qemu_kvm_wait_io_event(cpu);
> if (cpu->exit && !cpu_can_run(cpu)) {
> qemu_kvm_destroy_vcpu(cpu);
> + cpu->created = false;
> + qemu_cond_signal(&qemu_cpu_cond);
> qemu_mutex_unlock(&qemu_global_mutex);
> return NULL;
> }
> @@ -1174,6 +1176,8 @@ static void *qemu_tcg_cpu_thread_fn(void *arg)
> }
> if (remove_cpu) {
> qemu_tcg_destroy_vcpu(remove_cpu);
> + cpu->created = false;
> + qemu_cond_signal(&qemu_cpu_cond);
> remove_cpu = NULL;
> }
> }
> @@ -1339,6 +1343,14 @@ void cpu_remove(CPUState *cpu)
> qemu_cpu_kick(cpu);
> }
>
> +void cpu_remove_sync(CPUState *cpu)
> +{
> + cpu_remove(cpu);
> + while (cpu->created) {
> + qemu_cond_wait(&qemu_cpu_cond, &qemu_global_mutex);
> + }
> +}
> +
> /* For temporary buffers for forming a name */
> #define VCPU_THREAD_NAME_SIZE 16
>
> diff --git a/include/qom/cpu.h b/include/qom/cpu.h
> index 6a1d887..dc2b566 100644
> --- a/include/qom/cpu.h
> +++ b/include/qom/cpu.h
> @@ -705,6 +705,14 @@ void cpu_resume(CPUState *cpu);
> */
> void cpu_remove(CPUState *cpu);
>
> + /**
> + * cpu_remove_sync:
> + * @cpu: The CPU to remove.
> + *
> + * Requests the CPU to be removed and waits till it is removed.
> + */
> +void cpu_remove_sync(CPUState *cpu);
> +
> /**
> * qemu_init_vcpu:
> * @cpu: The vCPU to initialize.
>
