Logic memory-remove code fails to correctly account the Total High Memory
when a memory block which contains High Memory is offlined as shown in the
example below. The following patch fixes it.
cat /proc/meminfo
MemTotal: 7079452 kB
MemFree: 5805976 kB
Buffers: 94372 kB
Cached: 872000 kB
SwapCached: 0 kB
Active: 626936 kB
Inactive: 519236 kB
Active(anon): 180780 kB
Inactive(anon): 222944 kB
Active(file): 446156 kB
Inactive(file): 296292 kB
Unevictable: 0 kB
Mlocked: 0 kB
HighTotal: 7294672 kB
HighFree: 5181024 kB
LowTotal: 4294752076 kB
LowFree: 624952 kB
Signed-off-by: Wanpeng Li <[email protected]>
---
mm/page_alloc.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 98cbdf6..80474b2 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -6140,6 +6140,10 @@ __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
list_del(&page->lru);
rmv_page_order(page);
zone->free_area[order].nr_free--;
+#ifdef CONFIG_HIGHMEM
+ if (PageHighMem(page))
+ totalhigh_pages -= 1 << order;
+#endif
for (i = 0; i < (1 << order); i++)
SetPageReserved((page+i));
pfn += (1 << order);
--
1.8.1.2
hugetlb_prefault are not used any more, this patch remove it.
Signed-off-by: Wanpeng Li <[email protected]>
---
include/linux/hugetlb.h | 2 --
1 file changed, 2 deletions(-)
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 6b4890f..a811149 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -55,7 +55,6 @@ void __unmap_hugepage_range_final(struct mmu_gather *tlb,
void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
unsigned long start, unsigned long end,
struct page *ref_page);
-int hugetlb_prefault(struct address_space *, struct vm_area_struct *);
void hugetlb_report_meminfo(struct seq_file *);
int hugetlb_report_node_meminfo(int, char *);
void hugetlb_show_meminfo(void);
@@ -110,7 +109,6 @@ static inline unsigned long hugetlb_total_pages(void)
#define follow_hugetlb_page(m,v,p,vs,a,b,i,w) ({ BUG(); 0; })
#define follow_huge_addr(mm, addr, write) ERR_PTR(-EINVAL)
#define copy_hugetlb_page_range(src, dst, vma) ({ BUG(); 0; })
-#define hugetlb_prefault(mapping, vma) ({ BUG(); 0; })
static inline void hugetlb_report_meminfo(struct seq_file *m)
{
}
--
1.8.1.2
Use already exist interface huge_page_shift instead of h->order + PAGE_SHIFT.
Signed-off-by: Wanpeng Li <[email protected]>
---
mm/hugetlb.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index f8feeec..b6ff0ee 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -319,7 +319,7 @@ unsigned long vma_kernel_pagesize(struct vm_area_struct *vma)
hstate = hstate_vma(vma);
- return 1UL << (hstate->order + PAGE_SHIFT);
+ return 1UL << huge_page_shift(hstate);
}
EXPORT_SYMBOL_GPL(vma_kernel_pagesize);
--
1.8.1.2
get_pageblock_flags and set_pageblock_flags are not used any
more, this patch remove them.
Signed-off-by: Wanpeng Li <[email protected]>
---
include/linux/pageblock-flags.h | 6 ------
1 file changed, 6 deletions(-)
diff --git a/include/linux/pageblock-flags.h b/include/linux/pageblock-flags.h
index be655e4..2ee8cd2 100644
--- a/include/linux/pageblock-flags.h
+++ b/include/linux/pageblock-flags.h
@@ -80,10 +80,4 @@ void set_pageblock_flags_group(struct page *page, unsigned long flags,
PB_migrate_skip)
#endif /* CONFIG_COMPACTION */
-#define get_pageblock_flags(page) \
- get_pageblock_flags_group(page, 0, PB_migrate_end)
-#define set_pageblock_flags(page, flags) \
- set_pageblock_flags_group(page, flags, \
- 0, PB_migrate_end)
-
#endif /* PAGEBLOCK_FLAGS_H */
--
1.8.1.2
On Wed 22-05-13 17:29:27, Wanpeng Li wrote:
> Logic memory-remove code fails to correctly account the Total High Memory
> when a memory block which contains High Memory is offlined as shown in the
> example below. The following patch fixes it.
>
> cat /proc/meminfo
> MemTotal: 7079452 kB
> MemFree: 5805976 kB
> Buffers: 94372 kB
> Cached: 872000 kB
> SwapCached: 0 kB
> Active: 626936 kB
> Inactive: 519236 kB
> Active(anon): 180780 kB
> Inactive(anon): 222944 kB
> Active(file): 446156 kB
> Inactive(file): 296292 kB
> Unevictable: 0 kB
> Mlocked: 0 kB
> HighTotal: 7294672 kB
> HighFree: 5181024 kB
> LowTotal: 4294752076 kB
> LowFree: 624952 kB
Ok, so the HighTotal is higher than MemTotal but it would have been more
straightforward to show number of HighTotal before hotremove, show how
much memory has been removed and the number after.
It is not clear which stable kernels need this fix as well.
>
> Signed-off-by: Wanpeng Li <[email protected]>
Anyway
Reviewed-by: Michal Hocko <[email protected]>
with a nit pick bellow
> ---
> mm/page_alloc.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 98cbdf6..80474b2 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -6140,6 +6140,10 @@ __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
> list_del(&page->lru);
> rmv_page_order(page);
> zone->free_area[order].nr_free--;
> +#ifdef CONFIG_HIGHMEM
> + if (PageHighMem(page))
> + totalhigh_pages -= 1 << order;
> +#endif
ifdef shouldn't be necessary as PageHighMem should default to false for
!CONFIG_HIGHMEM AFAICS.
> for (i = 0; i < (1 << order); i++)
> SetPageReserved((page+i));
> pfn += (1 << order);
> --
> 1.8.1.2
>
> --
> To unsubscribe, send a message with 'unsubscribe linux-mm' in
> the body to [email protected]. For more info on Linux MM,
> see: http://www.linux-mm.org/ .
> Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
--
Michal Hocko
SUSE Labs
On Wed 22-05-13 17:29:28, Wanpeng Li wrote:
> get_pageblock_flags and set_pageblock_flags are not used any
> more, this patch remove them.
>
> Signed-off-by: Wanpeng Li <[email protected]>
Yes, git grep agrees
Reviewed-by: Michal Hocko <[email protected]>
> ---
> include/linux/pageblock-flags.h | 6 ------
> 1 file changed, 6 deletions(-)
>
> diff --git a/include/linux/pageblock-flags.h b/include/linux/pageblock-flags.h
> index be655e4..2ee8cd2 100644
> --- a/include/linux/pageblock-flags.h
> +++ b/include/linux/pageblock-flags.h
> @@ -80,10 +80,4 @@ void set_pageblock_flags_group(struct page *page, unsigned long flags,
> PB_migrate_skip)
> #endif /* CONFIG_COMPACTION */
>
> -#define get_pageblock_flags(page) \
> - get_pageblock_flags_group(page, 0, PB_migrate_end)
> -#define set_pageblock_flags(page, flags) \
> - set_pageblock_flags_group(page, flags, \
> - 0, PB_migrate_end)
> -
> #endif /* PAGEBLOCK_FLAGS_H */
> --
> 1.8.1.2
>
> --
> To unsubscribe, send a message with 'unsubscribe linux-mm' in
> the body to [email protected]. For more info on Linux MM,
> see: http://www.linux-mm.org/ .
> Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
--
Michal Hocko
SUSE Labs
On Wed 22-05-13 17:29:29, Wanpeng Li wrote:
> hugetlb_prefault are not used any more, this patch remove it.
>
> Signed-off-by: Wanpeng Li <[email protected]>
Reviewed-by: Michal Hocko <[email protected]>
> ---
> include/linux/hugetlb.h | 2 --
> 1 file changed, 2 deletions(-)
>
> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
> index 6b4890f..a811149 100644
> --- a/include/linux/hugetlb.h
> +++ b/include/linux/hugetlb.h
> @@ -55,7 +55,6 @@ void __unmap_hugepage_range_final(struct mmu_gather *tlb,
> void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
> unsigned long start, unsigned long end,
> struct page *ref_page);
> -int hugetlb_prefault(struct address_space *, struct vm_area_struct *);
> void hugetlb_report_meminfo(struct seq_file *);
> int hugetlb_report_node_meminfo(int, char *);
> void hugetlb_show_meminfo(void);
> @@ -110,7 +109,6 @@ static inline unsigned long hugetlb_total_pages(void)
> #define follow_hugetlb_page(m,v,p,vs,a,b,i,w) ({ BUG(); 0; })
> #define follow_huge_addr(mm, addr, write) ERR_PTR(-EINVAL)
> #define copy_hugetlb_page_range(src, dst, vma) ({ BUG(); 0; })
> -#define hugetlb_prefault(mapping, vma) ({ BUG(); 0; })
> static inline void hugetlb_report_meminfo(struct seq_file *m)
> {
> }
> --
> 1.8.1.2
>
--
Michal Hocko
SUSE Labs
On Wed 22-05-13 17:29:30, Wanpeng Li wrote:
> Use already exist interface huge_page_shift instead of h->order + PAGE_SHIFT.
alloc_bootmem_huge_page in powerpc uses the same construct so maybe you
want to udpate that one as well.
>
> Signed-off-by: Wanpeng Li <[email protected]>
Reviewed-by: Michal Hocko <[email protected]>
> ---
> mm/hugetlb.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index f8feeec..b6ff0ee 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -319,7 +319,7 @@ unsigned long vma_kernel_pagesize(struct vm_area_struct *vma)
>
> hstate = hstate_vma(vma);
>
> - return 1UL << (hstate->order + PAGE_SHIFT);
> + return 1UL << huge_page_shift(hstate);
> }
> EXPORT_SYMBOL_GPL(vma_kernel_pagesize);
>
> --
> 1.8.1.2
>
> --
> To unsubscribe, send a message with 'unsubscribe linux-mm' in
> the body to [email protected]. For more info on Linux MM,
> see: http://www.linux-mm.org/ .
> Don't email: <a href=mailto:"[email protected]"> [email protected] </a>
--
Michal Hocko
SUSE Labs
On Wed 22-05-13 12:49:37, Michal Hocko wrote:
> On Wed 22-05-13 17:29:27, Wanpeng Li wrote:
> > Logic memory-remove code fails to correctly account the Total High Memory
> > when a memory block which contains High Memory is offlined as shown in the
> > example below. The following patch fixes it.
> >
> > cat /proc/meminfo
> > MemTotal: 7079452 kB
> > MemFree: 5805976 kB
> > Buffers: 94372 kB
> > Cached: 872000 kB
> > SwapCached: 0 kB
> > Active: 626936 kB
> > Inactive: 519236 kB
> > Active(anon): 180780 kB
> > Inactive(anon): 222944 kB
> > Active(file): 446156 kB
> > Inactive(file): 296292 kB
> > Unevictable: 0 kB
> > Mlocked: 0 kB
> > HighTotal: 7294672 kB
> > HighFree: 5181024 kB
> > LowTotal: 4294752076 kB
> > LowFree: 624952 kB
>
> Ok, so the HighTotal is higher than MemTotal but it would have been more
> straightforward to show number of HighTotal before hotremove, show how
> much memory has been removed and the number after.
>
> It is not clear which stable kernels need this fix as well.
>
> >
> > Signed-off-by: Wanpeng Li <[email protected]>
>
> Anyway
> Reviewed-by: Michal Hocko <[email protected]>
>
> with a nit pick bellow
>
> > ---
> > mm/page_alloc.c | 4 ++++
> > 1 file changed, 4 insertions(+)
> >
> > diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> > index 98cbdf6..80474b2 100644
> > --- a/mm/page_alloc.c
> > +++ b/mm/page_alloc.c
> > @@ -6140,6 +6140,10 @@ __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
> > list_del(&page->lru);
> > rmv_page_order(page);
> > zone->free_area[order].nr_free--;
> > +#ifdef CONFIG_HIGHMEM
> > + if (PageHighMem(page))
> > + totalhigh_pages -= 1 << order;
> > +#endif
Hmm, it seems that my old gcc (4.3.4) doesn't like this.
mm/page_alloc.c:6202: error: lvalue required as left operand of assignment
I am not sure this is a compiler bug because PAGEFLAG_FALSE is clearly
returning 0 which should make the whole if a no-op... But maybe we
shouldn't be more clever than compiler.
Andrew, could you fold this follow up fix for
mm-memory-hotplug-fix-lowmem-count-overflow-when-offline-pages.patch
Sorr about the confusion I brought to this.
---
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 717286e..c164e5f 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -6198,8 +6198,10 @@ __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
list_del(&page->lru);
rmv_page_order(page);
zone->free_area[order].nr_free--;
+#ifdef CONFIG_HIGHMEM
if (PageHighMem(page))
totalhigh_pages -= 1 << order;
+#endif
for (i = 0; i < (1 << order); i++)
SetPageReserved((page+i));
pfn += (1 << order);
--
Michal Hocko
SUSE Labs