Re: [PATCH 2/2] fs/aio.c: use get_user_pages_non_movable() to pin ring pages when support memory hotremove

[Lin Feng <linfeng@cn.fujitsu.com>]

Hi Jeff,

On 02/04/2013 11:18 PM, Jeff Moyer wrote:
>> ---
>>  fs/aio.c | 6 ++++++
>>  1 file changed, 6 insertions(+)
>>
>> diff --git a/fs/aio.c b/fs/aio.c
>> index 71f613c..0e9b30a 100644
>> --- a/fs/aio.c
>> +++ b/fs/aio.c
>> @@ -138,9 +138,15 @@ static int aio_setup_ring(struct kioctx *ctx)
>>  	}
>>  
>>  	dprintk("mmap address: 0x%08lx\n", info->mmap_base);
>> +#ifdef CONFIG_MEMORY_HOTREMOVE
>> +	info->nr_pages = get_user_pages_non_movable(current, ctx->mm,
>> +					info->mmap_base, nr_pages,
>> +					1, 0, info->ring_pages, NULL);
>> +#else
>>  	info->nr_pages = get_user_pages(current, ctx->mm,
>>  					info->mmap_base, nr_pages, 
>>  					1, 0, info->ring_pages, NULL);
>> +#endif
> 
> Can't you hide this in your 1/1 patch, by providing this function as
> just a static inline wrapper around get_user_pages when
> CONFIG_MEMORY_HOTREMOVE is not enabled?
Good idea, it makes the callers more neatly :)

thanks,
linfeng