[RFC,v5,1/3] Introduce async_run_on_cpu()

Introduce an asynchronous version of run_on_cpu() i.e. the caller
 doesn't have to block till the call back routine finishes execution
 on the target vcpu.

Signed-off-by: Chegu Vinod <chegu_vinod@hp.com>
---
 cpus.c                |   29 +++++++++++++++++++++++++++++
 include/qemu-common.h |    1 +
 include/qom/cpu.h     |   10 ++++++++++
 3 files changed, 40 insertions(+), 0 deletions(-)

Il 09/05/2013 21:43, Chegu Vinod ha scritto:
>  Introduce an asynchronous version of run_on_cpu() i.e. the caller
>  doesn't have to block till the call back routine finishes execution
>  on the target vcpu.
> 
> Signed-off-by: Chegu Vinod <chegu_vinod@hp.com>
> ---
>  cpus.c                |   29 +++++++++++++++++++++++++++++
>  include/qemu-common.h |    1 +
>  include/qom/cpu.h     |   10 ++++++++++
>  3 files changed, 40 insertions(+), 0 deletions(-)
> 
> diff --git a/cpus.c b/cpus.c
> index c232265..8cd4eab 100644
> --- a/cpus.c
> +++ b/cpus.c
> @@ -653,6 +653,7 @@ void run_on_cpu(CPUState *cpu, void (*func)(void *data), void *data)
>  
>      wi.func = func;
>      wi.data = data;
> +    wi.free = false;
>      if (cpu->queued_work_first == NULL) {
>          cpu->queued_work_first = &wi;
>      } else {
> @@ -671,6 +672,31 @@ void run_on_cpu(CPUState *cpu, void (*func)(void *data), void *data)
>      }
>  }
>  
> +void async_run_on_cpu(CPUState *cpu, void (*func)(void *data), void *data)
> +{
> +    struct qemu_work_item *wi;
> +
> +    if (qemu_cpu_is_self(cpu)) {
> +        func(data);
> +        return;
> +    }
> +
> +    wi = g_malloc0(sizeof(struct qemu_work_item));
> +    wi->func = func;
> +    wi->data = data;
> +    wi->free = true;
> +    if (cpu->queued_work_first == NULL) {
> +        cpu->queued_work_first = wi;
> +    } else {
> +        cpu->queued_work_last->next = wi;
> +    }
> +    cpu->queued_work_last = wi;
> +    wi->next = NULL;
> +    wi->done = false;
> +
> +    qemu_cpu_kick(cpu);
> +}
> +
>  static void flush_queued_work(CPUState *cpu)
>  {
>      struct qemu_work_item *wi;
> @@ -683,6 +709,9 @@ static void flush_queued_work(CPUState *cpu)
>          cpu->queued_work_first = wi->next;
>          wi->func(wi->data);
>          wi->done = true;
> +        if (wi->free) {
> +            g_free(wi);
> +        }
>      }
>      cpu->queued_work_last = NULL;
>      qemu_cond_broadcast(&qemu_work_cond);
> diff --git a/include/qemu-common.h b/include/qemu-common.h
> index b399d85..bad6e1f 100644
> --- a/include/qemu-common.h
> +++ b/include/qemu-common.h
> @@ -286,6 +286,7 @@ struct qemu_work_item {
>      void (*func)(void *data);
>      void *data;
>      int done;
> +    bool free;
>  };
>  
>  #ifdef CONFIG_USER_ONLY
> diff --git a/include/qom/cpu.h b/include/qom/cpu.h
> index 7cd9442..46465e9 100644
> --- a/include/qom/cpu.h
> +++ b/include/qom/cpu.h
> @@ -265,6 +265,16 @@ bool cpu_is_stopped(CPUState *cpu);
>  void run_on_cpu(CPUState *cpu, void (*func)(void *data), void *data);
>  
>  /**
> + * async_run_on_cpu:
> + * @cpu: The vCPU to run on.
> + * @func: The function to be executed.
> + * @data: Data to pass to the function.
> + *
> + * Schedules the function @func for execution on the vCPU @cpu asynchronously.
> + */
> +void async_run_on_cpu(CPUState *cpu, void (*func)(void *data), void *data);
> +
> +/**
>   * qemu_for_each_cpu:
>   * @func: The function to be executed.
>   * @data: Data to pass to the function.
> 

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>