Re: [v6 04/15] mm: discard memblock data later

From	Pasha Tatashin <pasha.tatashin@oracle.com>
Newsgroups	linux.kernel
Subject	Re: [v6 04/15] mm: discard memblock data later
Date	2017-08-11 21:10 +0200
Message-ID	<udntL-7oX-3@gated-at.bofh.it> (permalink)
References	<ubX8m-5vB-5@gated-at.bofh.it> <ubX8m-5vB-19@gated-at.bofh.it> <udeA9-1Md-3@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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Hi Michal,

This suggestion won't work, because there are arches without memblock 
support: tile, sh...

So, I would still need to have:

#ifdef CONFIG_MEMBLOCK in page_alloc, or define memblock_discard() stubs 
in nobootmem headfile. In either case it would become messier than what 
it is right now.

Pasha

> I have just one nit below
> Acked-by: Michal Hocko <mhocko@suse.com>
> 
> [...]
>> diff --git a/mm/memblock.c b/mm/memblock.c
>> index 2cb25fe4452c..bf14aea6ab70 100644
>> --- a/mm/memblock.c
>> +++ b/mm/memblock.c
>> @@ -285,31 +285,27 @@ static void __init_memblock memblock_remove_region(struct memblock_type *type, u
>>   }
>>   
>>   #ifdef CONFIG_ARCH_DISCARD_MEMBLOCK
> 
> pull this ifdef inside memblock_discard and you do not have an another
> one in page_alloc_init_late
> 
> [...]
>> +/**
>> + * Discard memory and reserved arrays if they were allocated
>> + */
>> +void __init memblock_discard(void)
>>   {
> 
> here
> 
>> -	if (memblock.memory.regions == memblock_memory_init_regions)
>> -		return 0;
>> +	phys_addr_t addr, size;
>>   
>> -	*addr = __pa(memblock.memory.regions);
>> +	if (memblock.reserved.regions != memblock_reserved_init_regions) {
>> +		addr = __pa(memblock.reserved.regions);
>> +		size = PAGE_ALIGN(sizeof(struct memblock_region) *
>> +				  memblock.reserved.max);
>> +		__memblock_free_late(addr, size);
>> +	}
>>   
>> -	return PAGE_ALIGN(sizeof(struct memblock_region) *
>> -			  memblock.memory.max);
>> +	if (memblock.memory.regions == memblock_memory_init_regions) {
>> +		addr = __pa(memblock.memory.regions);
>> +		size = PAGE_ALIGN(sizeof(struct memblock_region) *
>> +				  memblock.memory.max);
>> +		__memblock_free_late(addr, size);
>> +	}
>>   }
>> -
>>   #endif

Thread

[v6 04/15] mm: discard memblock data later Pavel Tatashin <pasha.tatashin@oracle.com> - 2017-08-07 22:50 +0200
  Re: [v6 04/15] mm: discard memblock data later Michal Hocko <mhocko@kernel.org> - 2017-08-11 11:40 +0200
    Re: [v6 04/15] mm: discard memblock data later Mel Gorman <mgorman@techsingularity.net> - 2017-08-11 12:00 +0200
    Re: [v6 04/15] mm: discard memblock data later Pasha Tatashin <pasha.tatashin@oracle.com> - 2017-08-11 18:00 +0200
      Re: [v6 04/15] mm: discard memblock data later Michal Hocko <mhocko@kernel.org> - 2017-08-11 18:10 +0200
        Re: [v6 04/15] mm: discard memblock data later Pasha Tatashin <pasha.tatashin@oracle.com> - 2017-08-11 18:30 +0200
          Re: [v6 04/15] mm: discard memblock data later Michal Hocko <mhocko@kernel.org> - 2017-08-14 13:40 +0200
            Re: [v6 04/15] mm: discard memblock data later Pasha Tatashin <pasha.tatashin@oracle.com> - 2017-08-14 15:40 +0200
    Re: [v6 04/15] mm: discard memblock data later Pasha Tatashin <pasha.tatashin@oracle.com> - 2017-08-11 21:10 +0200
      Re: [v6 04/15] mm: discard memblock data later Michal Hocko <mhocko@kernel.org> - 2017-08-14 13:40 +0200
        Re: [v6 04/15] mm: discard memblock data later Michal Hocko <mhocko@kernel.org> - 2017-08-14 15:50 +0200
        Re: [v6 04/15] mm: discard memblock data later Pasha Tatashin <pasha.tatashin@oracle.com> - 2017-08-14 15:50 +0200

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