Hi Peter, On Fri, 22 Mar 2024 20:30:24 -0400 Peter Xu <peterx@xxxxxxxxxx> wrote: > On Fri, Mar 22, 2024 at 10:14:56AM -0700, SeongJae Park wrote: > > Hi Peter, > > Hi, SeongJae, > > > > > On Thu, 21 Mar 2024 18:07:53 -0400 peterx@xxxxxxxxxx wrote: > > > > > From: Peter Xu <peterx@xxxxxxxxxx> > > > > > > These macros can be helpful when we plan to merge hugetlb code into generic > > > code. Move them out and define them even if !THP. > > > > > > We actually already defined HPAGE_PMD_NR for other reasons even if !THP. > > > Reorganize these macros. > > > > > > Reviewed-by: Christoph Hellwig <hch@xxxxxxxxxxxxx> > > > Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx> > > > Signed-off-by: Peter Xu <peterx@xxxxxxxxxx> > > > --- > > > include/linux/huge_mm.h | 17 ++++++----------- > > > 1 file changed, 6 insertions(+), 11 deletions(-) > > > > > > diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h > > > index de0c89105076..3bcdfc7e5d57 100644 > > > --- a/include/linux/huge_mm.h > > > +++ b/include/linux/huge_mm.h > > > @@ -64,9 +64,6 @@ ssize_t single_hugepage_flag_show(struct kobject *kobj, > > > enum transparent_hugepage_flag flag); > > > extern struct kobj_attribute shmem_enabled_attr; > > > > > > -#define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT) > > > -#define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER) > > > - > > > /* > > > * Mask of all large folio orders supported for anonymous THP; all orders up to > > > * and including PMD_ORDER, except order-0 (which is not "huge") and order-1 > > > @@ -87,14 +84,19 @@ extern struct kobj_attribute shmem_enabled_attr; > > > #define thp_vma_allowable_order(vma, vm_flags, smaps, in_pf, enforce_sysfs, order) \ > > > (!!thp_vma_allowable_orders(vma, vm_flags, smaps, in_pf, enforce_sysfs, BIT(order))) > > > > > > -#ifdef CONFIG_TRANSPARENT_HUGEPAGE > > > #define HPAGE_PMD_SHIFT PMD_SHIFT > > > #define HPAGE_PMD_SIZE ((1UL) << HPAGE_PMD_SHIFT) > > > #define HPAGE_PMD_MASK (~(HPAGE_PMD_SIZE - 1)) > > > +#define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT) > > > +#define HPAGE_PMD_NR (1<<HPAGE_PMD_ORDER) > > > > > > #define HPAGE_PUD_SHIFT PUD_SHIFT > > > #define HPAGE_PUD_SIZE ((1UL) << HPAGE_PUD_SHIFT) > > > #define HPAGE_PUD_MASK (~(HPAGE_PUD_SIZE - 1)) > > > +#define HPAGE_PUD_ORDER (HPAGE_PUD_SHIFT-PAGE_SHIFT) > > > +#define HPAGE_PUD_NR (1<<HPAGE_PUD_ORDER) > > > > I just found latest mm-unstable fails one of my build configurations[1] with > > below error. 'git bisect' says this is the first patch set started the > > failure. I haven't looked in deep, but just reporting first. > > > > In file included from .../include/linux/mm.h:1115, > > from .../mm/vmstat.c:14: > > .../mm/vmstat.c: In function 'zoneinfo_show_print': > > .../include/linux/huge_mm.h:87:25: error: 'PMD_SHIFT' undeclared (first use in this function); did you mean 'PUD_SHIFT'? > > 87 | #define HPAGE_PMD_SHIFT PMD_SHIFT > > | ^~~~~~~~~ > > > > [1] https://github.com/awslabs/damon-tests/blob/next/corr/tests/build_m68k.sh > > Apologies for the issue. No problem at all, this blocks nothing in real :) > This is caused by !CONFIG_MMU, I think. > > I thought this would be fairly easy to fix by putting these macros under > CONFIG_PGTABLE_HAS_HUGE_LEAVES, however when doing this I could have found > some other issue that violates this rule.. mm/vmstat.c has referenced > HPAGE_PMD_NR even if vmstat_item_print_in_thp() wanted to guard it only > with CONFIG_THP. > > /home/peterx/git/linux/mm/vmstat.c: In function 'zoneinfo_show_print': > /home/peterx/git/linux/mm/vmstat.c:1689:42: error: 'HPAGE_PMD_NR' undeclared (first use in this function) > 1689 | pages /= HPAGE_PMD_NR; > | ^~~~~~~~~~~~ > /home/peterx/git/linux/mm/vmstat.c:1689:42: note: each undeclared identifier is reported only once for each function it appears in > CC drivers/tty/tty_port.o > /home/peterx/git/linux/mm/vmstat.c: In function 'vmstat_start': > /home/peterx/git/linux/mm/vmstat.c:1822:33: error: 'HPAGE_PMD_NR' undeclared (first use in this function) > 1822 | v[i] /= HPAGE_PMD_NR; > | ^~~~~~~~~~~~ > make[4]: *** [/home/peterx/git/linux/scripts/Makefile.build:243: mm/vmstat.o] Error 1 > > static __always_inline bool vmstat_item_print_in_thp(enum node_stat_item item) > { > if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) > return false; > ... > } > > I think the problem is vmstat_item_print_in_thp() uses IS_ENABLED() however > that won't stop compiler from looking into the "if".. so it'll still try to > find the HPAGE_PMD_NR macro. > > It means, I may need to further change vmstat_item_print_in_thp() to make > this work in the clean way.. by properly switching to a #ifdef. > > For that I'll need to post a formal patch and add people to review. I'll > keep you posted. Thank you for this kind explanation, all makes sense to me. Looking forward to the patch. > > Side note: thank you for your script, just to mention make.cross has been > moved to kbuild/, and it'll also need kbuild.sh now to work. So you may > want to fix your test script (and it worked for you because you kept the > old make.cross around), like: > > wget https://raw.githubusercontent.com/intel/lkp-tests/master/kbuild/make.cross -O ./bin/make.cross > wget https://raw.githubusercontent.com/intel/lkp-tests/master/kbuild/kbuild.sh -O ./bin/kbuild.sh And thank you so much for this nice suggestion. I'll revisit the script soon. Thanks, SJ > > Thanks, > > -- > Peter Xu
