On Thu, Aug 06, 2015 at 10:57:10AM +0530, Bharata B Rao wrote: > 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 <[email protected]> > --- > cpus.c | 14 ++++++++++++++ > include/qom/cpu.h | 8 ++++++++ > 2 files changed, 22 insertions(+) > > diff --git a/cpus.c b/cpus.c > index 73ae2e7..9d9644e 100644 > --- a/cpus.c > +++ b/cpus.c > @@ -999,6 +999,8 @@ 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; > } > @@ -1104,6 +1106,8 @@ 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; > } > } > @@ -1283,6 +1287,16 @@ void cpu_remove(CPUState *cpu) > qemu_cpu_kick(cpu); > } > > +void cpu_remove_sync(CPUState *cpu) > +{ > + cpu->stop = true; > + cpu->exit = true; > + qemu_cpu_kick(cpu);
It would be nicer for this to call the async cpu_remove() above, to
ensure they stay in sync.
> + 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 136d9fe..65c6852 100644
> --- a/include/qom/cpu.h
> +++ b/include/qom/cpu.h
> @@ -655,6 +655,14 @@ 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.
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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