On Wed, Jun 17, 2020 at 11:38:03AM +0000, Song Bao Hua (Barry Song) wrote: > > > > -----Original Message----- > > From: Will Deacon [mailto:w...@kernel.org] > > Sent: Wednesday, June 17, 2020 10:18 PM > > To: Song Bao Hua (Barry Song) <song.bao....@hisilicon.com> > > Cc: catalin.mari...@arm.com; nsaenzjulie...@suse.de; > > steve.cap...@arm.com; r...@linux.ibm.com; a...@linux-foundation.org; > > linux-arm-ker...@lists.infradead.org; linux-kernel@vger.kernel.org; Linuxarm > > <linux...@huawei.com>; Matthias Brugger <matthias....@gmail.com>; > > Roman Gushchin <g...@fb.com> > > Subject: Re: [PATCH v2] arm64: mm: reserve hugetlb CMA after numa_init > > > > On Wed, Jun 17, 2020 at 10:19:24AM +1200, Barry Song wrote: > > > hugetlb_cma_reserve() is called at the wrong place. numa_init has not been > > > done yet. so all reserved memory will be located at node0. > > > > > > Fixes: cf11e85fc08c ("mm: hugetlb: optionally allocate gigantic hugepages > > using cma") > > > > Damn, wasn't CC'd on that :/ > > > > > Cc: Matthias Brugger <matthias....@gmail.com> > > > Acked-by: Roman Gushchin <g...@fb.com> > > > Signed-off-by: Barry Song <song.bao....@hisilicon.com> > > > --- > > > -v2: add Fixes tag according to Matthias Brugger's comment > > > > > > arch/arm64/mm/init.c | 10 +++++----- > > > 1 file changed, 5 insertions(+), 5 deletions(-) > > > > > > diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c > > > index e631e6425165..41914b483d54 100644 > > > --- a/arch/arm64/mm/init.c > > > +++ b/arch/arm64/mm/init.c > > > @@ -404,11 +404,6 @@ void __init arm64_memblock_init(void) > > > high_memory = __va(memblock_end_of_DRAM() - 1) + 1; > > > > > > dma_contiguous_reserve(arm64_dma32_phys_limit); > > > - > > > -#ifdef CONFIG_ARM64_4K_PAGES > > > - hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT); > > > -#endif > > > > Why is this dependent on CONFIG_ARM64_4K_PAGES? We unconditionally > > select ARCH_HAS_GIGANTIC_PAGE so this seems unnecessary. > > Roman, would you like to answer this question? Have you found any problem if > system > doesn't set 4K_PAGES?
No, I was just following the code in arch/arm64/mm/hugetlbpage.c where all related to PUD-sized pages is guarded by CONFIG_ARM64_4K_PAGES. Actually I did all my testing on x86-64, I don't even have any arm hardware. I'm totally fine with removing this #ifdef if it's not needed. Thanks! > > > > > > - > > > } > > > > > > void __init bootmem_init(void) > > > @@ -424,6 +419,11 @@ void __init bootmem_init(void) > > > min_low_pfn = min; > > > > > > arm64_numa_init(); > > > + > > > +#ifdef CONFIG_ARM64_4K_PAGES > > > + hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT); > > > +#endif > > > > A comment here wouldn't hurt, as it does look a lot more natural next > > to dma_contiguous_reserve(). > > Will add some comment here. > > > > > Will > > barry
