Re: [PATCH] rtas_errd: Add support for cpu and memory hotplugging via RTAS event

On 11/04/2014 12:33 PM, Thomas Falcon wrote:
> This patch adds support for handling RTAS hotplug events for cpus and memory
> blocks in addition to such events for pci devices. It includes additional
> support for events indicating an addition or a removal of multiple cpus or
> logical memory blocks. Finally, for debugging purposes, it includes the option
> to handle the event without calling the drmgr command.
> 
> Signed-off-by: Thomas Falcon <[email protected]>

Acked-by: Nathan Fontenot <[email protected]>

Vasant, testing this right now is limited to feeding rtas_errd a cpu or
hotplug memory rtas event. This patch is in preparation for supporting
cpu and memory hotplug on kvm guests that are running older kernels
that do not have the kernel hotplug support for cpu/mem hotplug.

This patch follows the same thing we currently do for pci hotplug and
is just a stop-gap measuere until all of the kernel code makes it
upstream and into the distro releases.

-Nathan 

> ---
>  rtas_errd/hotplug.c | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 
> diff --git a/rtas_errd/hotplug.c b/rtas_errd/hotplug.c
> index 0f84f8d..91036b2 100644
> --- a/rtas_errd/hotplug.c
> +++ b/rtas_errd/hotplug.c
> @@ -24,6 +24,7 @@ void handle_hotplug_event(struct event *re)
>          pid_t child;
>          int status, rc;
>          char drc_index[11];
> +	char count[4];
>          char *drmgr_args[] = { DRMGR_PROGRAM_NOPATH, "-c", NULL, NULL, NULL,
>                          NULL, NULL, "-d4", "-V", NULL};
> 
> @@ -39,6 +40,12 @@ void handle_hotplug_event(struct event *re)
>                                  drmgr_args[2] = "pci";
>                                  drmgr_args[6] = "-n";
>                                  break;
> +			case RTAS_HP_TYPE_CPU:
> +				drmgr_args[2] = "cpu";
> +				break;
> +			case RTAS_HP_TYPE_MEMORY:
> +				drmgr_args[2] = "mem";
> +                                break;
>                          default:
>                                  dbg("Unknown or unsupported hotplug type %d\n",
>  					hotplug->type);
> @@ -63,6 +70,11 @@ void handle_hotplug_event(struct event *re)
>                                  snprintf(drc_index, 11, "%#x", hotplug->u1.drc_index);
>                                  drmgr_args[5] = drc_index;
>                                  break;
> +			case RTAS_HP_ID_DRC_COUNT:
> +				drmgr_args[4] = "-q";
> +				snprintf(count, 4, "%u", hotplug->u1.count);
> +				drmgr_args[5] = count;
> +				break;
>                          default:
>                                  dbg("Unknown or unsupported hotplug identifier %d\n",
>  					hotplug->identifier);
> @@ -73,6 +85,10 @@ void handle_hotplug_event(struct event *re)
>                          drmgr_args[1], drmgr_args[2], drmgr_args[3],
>                          drmgr_args[4], drmgr_args[5], drmgr_args[6]);
> 
> +#ifdef DEBUG
> +		if(no_drmgr)
> +			return;
> +#endif
>                  /* invoke drmgr */
>                  dbg("Invoke drmgr command\n");
> 


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