Re: [PATCH] memblock: Introduce memblock_reserve_node()

["Yajun Deng" <yajun.deng@linux.dev>]

June 27, 2023 10:33 PM, "Mike Rapoport" <rppt@kernel.org> wrote:

> On Tue, Jun 27, 2023 at 12:13:16AM +0000, Yajun Deng wrote:
> 
>> June 26, 2023 2:21 PM, "Mike Rapoport" <rppt@kernel.org> wrote:
>> 
>> On Sun, Jun 25, 2023 at 07:39:10AM +0000, Yajun Deng wrote:
>> 
>> June 25, 2023 1:08 PM, "Mike Rapoport" <rppt@kernel.org> wrote:
>> 
>> On Sat, Jun 24, 2023 at 10:46:22AM +0800, Yajun Deng wrote:
>> 
>> It only returns address now in memblock_find_in_range_node(), we can add a
>> parameter pointing to integer for node id of the range, which can be used
>> to pass the node id to the new reserve region.
>> 
>> Introduce memblock_reserve_node() so that the node id can be passed to
>> the reserve region in memblock_alloc_range_nid().
>> 
>> Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
>> 
>> What problem does this patch solve?
>> 
>> If we set nid and flags in memblock_alloc_range_nid(), we may not need
>> memblock_set_node() in memmap_init_reserved_pages().
>> 
>> When memblock_reserve() is called before NUMA setup, the node ids are still
>> unset in memblock.memory, so very early reservations will be missed and we
>> still have to update node ids in memblock.reserved later.
>> 
>> Even so, we still need to pass the 'flags' to the new reserve region.
>> choose_memblock_flags() may return MEMBLOCK_MIRROR in memblock_alloc_range_nid(),
>> memblock_reserve() couldn't pass this flag in this case.
> 
> flags are only relevant to memblock.memory, we don't care about the flags
> in memblock.reserved.
> 

get it.

>> I tested this patch and delete memblock_set_node() in memmap_init_reserved_pages().
>> It works fine. I did not delete memblock_set_node() in this patch just in case.
>> 
>> --
>> Sincerely yours,
>> Mike.
> 
> --
> Sincerely yours,
> Mike.