Re: [PATCH v2 12/12] mm: memory_hotplug: memory hotremove supports thp migration
From: Naoya Horiguchi
Date: Mon Nov 07 2016 - 20:42:23 EST
On Tue, Nov 08, 2016 at 08:30:10AM +0800, kbuild test robot wrote:
> Hi Naoya,
>
> [auto build test WARNING on mmotm/master]
> [also build test WARNING on next-20161028]
> [cannot apply to v4.9-rc4]
> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
>
> url: https://github.com/0day-ci/linux/commits/Naoya-Horiguchi/mm-x86-move-_PAGE_SWP_SOFT_DIRTY-from-bit-7-to-bit-6/20161108-080615
> base: git://git.cmpxchg.org/linux-mmotm.git master
> config: x86_64-randconfig-x003-201645 (attached as .config)
> compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
> reproduce:
> # save the attached .config to linux build tree
> make ARCH=x86_64
>
> All warnings (new ones prefixed by >>):
>
> mm/memory_hotplug.c: In function 'try_offline_node':
> mm/memory_hotplug.c:2131:6: warning: unused variable 'i' [-Wunused-variable]
> int i;
> ^
> In file included from include/uapi/linux/stddef.h:1:0,
> from include/linux/stddef.h:4,
> from mm/memory_hotplug.c:7:
This seems unrelated to my patchset, but the fix is easy.
I'll post a separate patch later.
> mm/memory_hotplug.c: In function 'new_node_page':
> include/linux/compiler.h:518:38: error: call to '__compiletime_assert_1575' declared with attribute error: BUILD_BUG failed
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^
> include/linux/compiler.h:160:16: note: in definition of macro '__trace_if'
> ______r = !!(cond); \
> ^~~~
> >> mm/memory_hotplug.c:1575:2: note: in expansion of macro 'if'
> if (new_page && order == HPAGE_PMD_ORDER)
> ^~
> include/linux/compiler.h:506:2: note: in expansion of macro '__compiletime_assert'
> __compiletime_assert(condition, msg, prefix, suffix)
> ^~~~~~~~~~~~~~~~~~~~
> include/linux/compiler.h:518:2: note: in expansion of macro '_compiletime_assert'
> _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__)
> ^~~~~~~~~~~~~~~~~~~
> include/linux/bug.h:54:37: note: in expansion of macro 'compiletime_assert'
> #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
> ^~~~~~~~~~~~~~~~~~
> include/linux/bug.h:88:21: note: in expansion of macro 'BUILD_BUG_ON_MSG'
> #define BUILD_BUG() BUILD_BUG_ON_MSG(1, "BUILD_BUG failed")
> ^~~~~~~~~~~~~~~~
> include/linux/huge_mm.h:181:28: note: in expansion of macro 'BUILD_BUG'
> #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
> ^~~~~~~~~
> include/linux/huge_mm.h:56:26: note: in expansion of macro 'HPAGE_PMD_SHIFT'
> #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT)
> ^~~~~~~~~~~~~~~
> mm/memory_hotplug.c:1575:27: note: in expansion of macro 'HPAGE_PMD_ORDER'
> if (new_page && order == HPAGE_PMD_ORDER)
> ^~~~~~~~~~~~~~~
HPAGE_PMD_ORDER is not available in non-thp code now, so let's add
a simple wrapper to access it in generic code.
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index 3c252cdef587..b75a9a1bbf3e 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -148,6 +148,12 @@ static inline int hpage_nr_pages(struct page *page)
return HPAGE_PMD_NR;
return 1;
}
+static inline int hpage_order(struct page *page)
+{
+ if (unlikely(PageTransHuge(page)))
+ return HPAGE_PMD_ORDER;
+ return 0;
+}
extern int do_huge_pmd_numa_page(struct fault_env *fe, pmd_t orig_pmd);
@@ -183,6 +189,7 @@ static inline bool thp_migration_supported(void)
#define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
#define hpage_nr_pages(x) 1
+#define hpage_order(x) 0
#define transparent_hugepage_enabled(__vma) 0
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index a9c3fe1b55ea..d612a75ceec4 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1555,7 +1555,7 @@ static struct page *new_node_page(struct page *page, unsigned long private,
next_node_in(nid, nmask));
if (thp_migration_supported() && PageTransHuge(page)) {
- order = HPAGE_PMD_ORDER;
+ order = hpage_order(page);
gfp_mask |= GFP_TRANSHUGE;
}
@@ -1572,7 +1572,7 @@ static struct page *new_node_page(struct page *page, unsigned long private,
new_page = __alloc_pages(gfp_mask, order,
node_zonelist(nid, gfp_mask));
- if (new_page && order == HPAGE_PMD_ORDER)
+ if (new_page && order == hpage_order(page))
prep_transhuge_page(new_page);
return new_page;
@@ -1606,7 +1606,7 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
continue;
} else if (thp_migration_supported() && PageTransHuge(page))
pfn = page_to_pfn(compound_head(page))
- + HPAGE_PMD_NR - 1;
+ + hpage_nr_pages(page) - 1;
if (!get_page_unless_zero(page))
continue;
These changes are applied in the next version.
Thanks,
Naoya Horiguchi
>
> vim +/if +1575 mm/memory_hotplug.c
>
> 1559 gfp_mask |= GFP_TRANSHUGE;
> 1560 }
> 1561
> 1562 node_clear(nid, nmask);
> 1563
> 1564 if (PageHighMem(page)
> 1565 || (zone_idx(page_zone(page)) == ZONE_MOVABLE))
> 1566 gfp_mask |= __GFP_HIGHMEM;
> 1567
> 1568 if (!nodes_empty(nmask))
> 1569 new_page = __alloc_pages_nodemask(gfp_mask, order,
> 1570 node_zonelist(nid, gfp_mask), &nmask);
> 1571 if (!new_page)
> 1572 new_page = __alloc_pages(gfp_mask, order,
> 1573 node_zonelist(nid, gfp_mask));
> 1574
> > 1575 if (new_page && order == HPAGE_PMD_ORDER)
> 1576 prep_transhuge_page(new_page);
> 1577
> 1578 return new_page;
> 1579 }
> 1580
> 1581 #define NR_OFFLINE_AT_ONCE_PAGES (256)
> 1582 static int
> 1583 do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
>
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