Re: [PATCH] Driver core / memory: Simplify __memory_block_change_state()

[Tang Chen <tangchen@cn.fujitsu.com>]

Reviewed-by: Tang Chen <tangchen@cn.fujitsu.com>

Thanks. :)

On 05/23/2013 06:06 AM, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki<rafael.j.wysocki@intel.com>
>
> As noted by Tang Chen, the last_online field in struct memory_block
> introduced by commit 4960e05 (Driver core: Introduce offline/online
> callbacks for memory blocks) is not really necessary, because
> online_pages() restores the previous state if passed ONLINE_KEEP as
> the last argument.  Therefore, remove that field along with the code
> referring to it.
>
> References: http://marc.info/?l=linux-kernel&m=136919777305599&w=2
> Signed-off-by: Rafael J. Wysocki<rafael.j.wysocki@intel.com>
> ---
>
> Hi,
>
> The patch is on top (and the commit mentioned in the changelog is present in)
> the acpi-hotplug branch of the linux-pm.git tree.
>
> Thanks,
> Rafael
>
> ---
>   drivers/base/memory.c  |   11 ++---------
>   include/linux/memory.h |    1 -
>   2 files changed, 2 insertions(+), 10 deletions(-)
>
> Index: linux-pm/drivers/base/memory.c
> ===================================================================
> --- linux-pm.orig/drivers/base/memory.c
> +++ linux-pm/drivers/base/memory.c
> @@ -291,13 +291,7 @@ static int __memory_block_change_state(s
>   		mem->state = MEM_GOING_OFFLINE;
>
>   	ret = memory_block_action(mem->start_section_nr, to_state, online_type);
> -	if (ret) {
> -		mem->state = from_state_req;
> -	} else {
> -		mem->state = to_state;
> -		if (to_state == MEM_ONLINE)
> -			mem->last_online = online_type;
> -	}
> +	mem->state = ret ? from_state_req : to_state;
>   	return ret;
>   }
>
> @@ -310,7 +304,7 @@ static int memory_subsys_online(struct d
>
>   	ret = mem->state == MEM_ONLINE ? 0 :
>   		__memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE,
> -					    mem->last_online);
> +					    ONLINE_KEEP);
>
>   	mutex_unlock(&mem->state_mutex);
>   	return ret;
> @@ -618,7 +612,6 @@ static int init_memory_block(struct memo
>   			base_memory_block_id(scn_nr) * sections_per_block;
>   	mem->end_section_nr = mem->start_section_nr + sections_per_block - 1;
>   	mem->state = state;
> -	mem->last_online = ONLINE_KEEP;
>   	mem->section_count++;
>   	mutex_init(&mem->state_mutex);
>   	start_pfn = section_nr_to_pfn(mem->start_section_nr);
> Index: linux-pm/include/linux/memory.h
> ===================================================================
> --- linux-pm.orig/include/linux/memory.h
> +++ linux-pm/include/linux/memory.h
> @@ -26,7 +26,6 @@ struct memory_block {
>   	unsigned long start_section_nr;
>   	unsigned long end_section_nr;
>   	unsigned long state;
> -	int last_online;
>   	int section_count;
>
>   	/*
>
>