[Qemu-devel] Re: [PATCH 5/6] enable cpu hotplug

[Anthony Liguori]

Glauber Costa wrote:
> This patch enable cpu hotplug to happen via acpi events.
> Note that all it does is generate acpi messages. It still needs
> guest cooperation, in the very way as real hardware.
>
> It is basically what we have in kvm, but in a qemuish style, with
> a few improvements.
>
> Signed-off-by: Glauber Costa <address@hidden>
> ---
>  cpu-all.h |    1 +
>  exec.c    |   13 +++++++++++
>  hw/acpi.c |   69 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  monitor.c |   21 ++++++++++++++++++
>  sysemu.h  |    1 +
>  5 files changed, 105 insertions(+), 0 deletions(-)
>
> diff --git a/cpu-all.h b/cpu-all.h
> index aaaa70d..a0c97f7 100644
> --- a/cpu-all.h
> +++ b/cpu-all.h
> @@ -745,6 +745,7 @@ int page_check_range(target_ulong start, target_ulong len, 
> int flags);
>
>  void cpu_exec_init_all(unsigned long tb_size);
>  CPUState *cpu_copy(CPUState *env);
> +CPUState *qemu_get_cpu(int cpu);
>
>  void cpu_dump_state(CPUState *env, FILE *f,
>                      int (*cpu_fprintf)(FILE *f, const char *fmt, ...),
> diff --git a/exec.c b/exec.c
> index 13e43d0..a7ac18f 100644
> --- a/exec.c
> +++ b/exec.c
> @@ -538,6 +538,19 @@ static int cpu_common_load(QEMUFile *f, void *opaque, int 
> version_id)
>  }
>  #endif
>
> +CPUState *qemu_get_cpu(int cpu)
> +{
> +    CPUState *env = first_cpu;
> +
> +    while (env) {
> +        if (env->cpu_index == cpu)
> +            break;
> +        env = env->next_cpu;
> +    }
> +
> +    return env;
> +}
> +
>  void cpu_exec_init(CPUState *env)
>  {
>      CPUState **penv;
> diff --git a/hw/acpi.c b/hw/acpi.c
> index 22fbc4a..10c0e69 100644
> --- a/hw/acpi.c
> +++ b/hw/acpi.c
> @@ -26,6 +26,7 @@
>  #include "kvm.h"
>
>  //#define DEBUG
> +//#define DEBUG_CPU
>   

Consider introducing a cpu_dprintf() or something like that.

> @@ -709,11 +712,44 @@ static void pciej_write(void *opaque, uint32_t addr, 
> uint32_t val)
>  #endif
>  }
>
> +static uint32_t cpuhotplug_read(void *opaque, uint32_t addr)
> +{
> +    if ((addr < PROC_BASE) || (addr > (PROC_BASE + 31))) {
> +        /* should never happen, so return a poison */
> +        return 0xabcdefab;
> +    }
> +    else {
>   

Should be one line.

> +void qemu_system_cpu_hot_add(int cpu, int state)
> +{
> +    CPUState *env;
> +
> +    if ((state) && !qemu_get_cpu(cpu)) {
> +#ifdef DEBUG_CPU
> +        printf("creatng new cpu %d\n", cpu);
> +#endif
> +        env = pc_new_cpu(cpu, first_cpu->cpu_model_str, 1);
> +        enable_processor(&gpe, cpu);
> +    }
> +    else {
>   

Should be one line.

> +
> +    if (!strcmp(status, "online"))
> +       state = 1;
> +    else if (!strcmp(status, "offline"))
> +       state = 0;
>   

Should have {}s.


--
Regards,

Anthony Liguori