Re: [PATCH v2 7/8] mm/memory_hotplug: convert memhp_auto_online to store an online_type

[Michal Hocko]

On Tue 17-03-20 11:49:41, David Hildenbrand wrote:
> ... and rename it to memhp_default_online_type. This is a preparation
> for more detailed default online behavior.
> 
> Reviewed-by: Wei Yang <richard.weiyang@xxxxxxxxx>
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Cc: Michal Hocko <mhocko@xxxxxxxxxx>
> Cc: Oscar Salvador <osalvador@xxxxxxx>
> Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx>
> Cc: Baoquan He <bhe@xxxxxxxxxx>
> Cc: Wei Yang <richard.weiyang@xxxxxxxxx>
> Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>

Acked-by: Michal Hocko <mhocko@xxxxxxxx>

> ---
>  drivers/base/memory.c          | 10 ++++------
>  include/linux/memory_hotplug.h |  3 ++-
>  mm/memory_hotplug.c            | 11 ++++++-----
>  3 files changed, 12 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/base/memory.c b/drivers/base/memory.c
> index 8a7f29c0bf97..8d3e16dab69f 100644
> --- a/drivers/base/memory.c
> +++ b/drivers/base/memory.c
> @@ -386,10 +386,8 @@ static DEVICE_ATTR_RO(block_size_bytes);
>  static ssize_t auto_online_blocks_show(struct device *dev,
>  				       struct device_attribute *attr, char *buf)
>  {
> -	if (memhp_auto_online)
> -		return sprintf(buf, "online\n");
> -	else
> -		return sprintf(buf, "offline\n");
> +	return sprintf(buf, "%s\n",
> +		       online_type_to_str[memhp_default_online_type]);
>  }
>  
>  static ssize_t auto_online_blocks_store(struct device *dev,
> @@ -397,9 +395,9 @@ static ssize_t auto_online_blocks_store(struct device *dev,
>  					const char *buf, size_t count)
>  {
>  	if (sysfs_streq(buf, "online"))
> -		memhp_auto_online = true;
> +		memhp_default_online_type = MMOP_ONLINE;
>  	else if (sysfs_streq(buf, "offline"))
> -		memhp_auto_online = false;
> +		memhp_default_online_type = MMOP_OFFLINE;
>  	else
>  		return -EINVAL;
>  
> diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
> index c2e06ed5e0e9..c6e090b34c4b 100644
> --- a/include/linux/memory_hotplug.h
> +++ b/include/linux/memory_hotplug.h
> @@ -117,7 +117,8 @@ extern int arch_add_memory(int nid, u64 start, u64 size,
>  			struct mhp_restrictions *restrictions);
>  extern u64 max_mem_size;
>  
> -extern bool memhp_auto_online;
> +/* Default online_type (MMOP_*) when new memory blocks are added. */
> +extern int memhp_default_online_type;
>  /* If movable_node boot option specified */
>  extern bool movable_node_enabled;
>  static inline bool movable_node_is_enabled(void)
> diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
> index 2d2aae830b92..1975a2b99a2b 100644
> --- a/mm/memory_hotplug.c
> +++ b/mm/memory_hotplug.c
> @@ -67,17 +67,17 @@ void put_online_mems(void)
>  bool movable_node_enabled = false;
>  
>  #ifndef CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE
> -bool memhp_auto_online;
> +int memhp_default_online_type = MMOP_OFFLINE;
>  #else
> -bool memhp_auto_online = true;
> +int memhp_default_online_type = MMOP_ONLINE;
>  #endif
>  
>  static int __init setup_memhp_default_state(char *str)
>  {
>  	if (!strcmp(str, "online"))
> -		memhp_auto_online = true;
> +		memhp_default_online_type = MMOP_ONLINE;
>  	else if (!strcmp(str, "offline"))
> -		memhp_auto_online = false;
> +		memhp_default_online_type = MMOP_OFFLINE;
>  
>  	return 1;
>  }
> @@ -990,6 +990,7 @@ static int check_hotplug_memory_range(u64 start, u64 size)
>  
>  static int online_memory_block(struct memory_block *mem, void *arg)
>  {
> +	mem->online_type = memhp_default_online_type;
>  	return device_online(&mem->dev);
>  }
>  
> @@ -1062,7 +1063,7 @@ int __ref add_memory_resource(int nid, struct resource *res)
>  	mem_hotplug_done();
>  
>  	/* online pages if requested */
> -	if (memhp_auto_online)
> +	if (memhp_default_online_type != MMOP_OFFLINE)
>  		walk_memory_blocks(start, size, NULL, online_memory_block);
>  
>  	return ret;
> -- 
> 2.24.1

-- 
Michal Hocko
SUSE Labs