> -----Original Message----- > From: liwei (CM) > Sent: Wednesday, July 8, 2020 7:52 PM > To: Song Bao Hua (Barry Song) <[email protected]>; > [email protected]; [email protected] > Cc: fengbaopeng <[email protected]>; [email protected]; > [email protected]; [email protected]; > [email protected]; [email protected]; sujunfei > <[email protected]>; Xiaqing (A) <[email protected]>; > Yaobaofeng (Yaobaofeng) <[email protected]> > Subject: 答复: [PATCH] arm64: mm: free unused memmap for sparse memory > model that define VMEMMAP > > Hi, baohua > > Thank you for your attention. > > In my understanding of the MEMORY_HOTPLUG this patch has no effect on it. > The reason is that in sparse_add_one_section() the memory that memmap > needs from Slab if kernel start completed，this memory has nothing to do with > memblock alloc/ free memory in the process of kernel start. > > You may have a look vmemmap_alloc_block () this function. > > If I don't understand right welcome pointed out in a timely manner.
At the first glance of this patch, I suspect that this bootmem may be used by hot-added memory. If you confirm this won't happen, please ignore my noise. BTW, next time, bear in mind that top-post is not a good way to reply mail :-) > > Thanks! > > > -----邮件原件----- > 发件人: Song Bao Hua (Barry Song) > 发送时间: 2020年7月8日 15:19 > 收件人: liwei (CM) <[email protected]>; [email protected]; > [email protected] > 抄送: fengbaopeng <[email protected]>; [email protected]; > [email protected]; [email protected]; > [email protected]; [email protected]; sujunfei > <[email protected]> > 主题: RE: [PATCH] arm64: mm: free unused memmap for sparse memory > model that define VMEMMAP > > > > > -----Original Message----- > > From: liwei (CM) > > Sent: Wednesday, July 8, 2020 1:56 PM > > To: [email protected]; [email protected] > > Cc: liwei (CM) <[email protected]>; fengbaopeng > > <[email protected]>; [email protected]; > > [email protected]; [email protected]; Song Bao Hua (Barry Song) > > <[email protected]>; [email protected]; > > [email protected]; sujunfei <[email protected]> > > Subject: [PATCH] arm64: mm: free unused memmap for sparse memory > model > > that define VMEMMAP > > > > For the memory hole, sparse memory model that define > SPARSEMEM_VMEMMAP > > do not free the reserved memory for the page map, this patch do it. > > Hello Wei, > Just curious if this patch breaks MEMORY_HOTPLUG? > > > > > Signed-off-by: Wei Li <[email protected]> > > Signed-off-by: Chen Feng <[email protected]> > > Signed-off-by: Xia Qing <[email protected]> > > --- > > arch/arm64/mm/init.c | 81 > > +++++++++++++++++++++++++++++++++++++++++++++------- > > 1 file changed, 71 insertions(+), 10 deletions(-) > > > > diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index > > 1e93cfc7c47a..d1b56b47d5ba 100644 > > --- a/arch/arm64/mm/init.c > > +++ b/arch/arm64/mm/init.c > > @@ -441,7 +441,48 @@ void __init bootmem_init(void) > > memblock_dump_all(); > > } > > > > Thanks > Barry
