Patchwork [-V6,16/27] mm/THP: HPAGE_SHIFT is not a #define on some arch

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Submitter Aneesh Kumar K.V
Date April 22, 2013, 10 a.m.
Message ID <1366624861-24948-17-git-send-email-aneesh.kumar@linux.vnet.ibm.com>
Download mbox | patch
Permalink /patch/238413/
State Superseded
Headers show

Comments

Aneesh Kumar K.V - April 22, 2013, 10 a.m.
From: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>

On archs like powerpc that support different hugepage sizes, HPAGE_SHIFT
and other derived values like HPAGE_PMD_ORDER are not constants. So move
that to hugepage_init

Cc: Andrea Arcangeli <aarcange@redhat.com>

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
---
 include/linux/huge_mm.h |    3 ---
 mm/huge_memory.c        |    9 ++++++---
 2 files changed, 6 insertions(+), 6 deletions(-)
Andrea Arcangeli - April 22, 2013, 3:43 p.m.
On Mon, Apr 22, 2013 at 03:30:50PM +0530, Aneesh Kumar K.V wrote:
> From: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
> 
> On archs like powerpc that support different hugepage sizes, HPAGE_SHIFT
> and other derived values like HPAGE_PMD_ORDER are not constants. So move
> that to hugepage_init
> 
> Cc: Andrea Arcangeli <aarcange@redhat.com>
> 
> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>

Patch

diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index ee1c244..bdc5aef 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -119,9 +119,6 @@  extern void __split_huge_page_pmd(struct vm_area_struct *vma,
 	} while (0)
 extern void split_huge_page_pmd_mm(struct mm_struct *mm, unsigned long address,
 		pmd_t *pmd);
-#if HPAGE_PMD_ORDER > MAX_ORDER
-#error "hugepages can't be allocated by the buddy allocator"
-#endif
 extern int hugepage_madvise(struct vm_area_struct *vma,
 			    unsigned long *vm_flags, int advice);
 extern void __vma_adjust_trans_huge(struct vm_area_struct *vma,
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index e2f7f5aa..78bd84f 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -45,7 +45,7 @@  unsigned long transparent_hugepage_flags __read_mostly =
 	(1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG);
 
 /* default scan 8*512 pte (or vmas) every 30 second */
-static unsigned int khugepaged_pages_to_scan __read_mostly = HPAGE_PMD_NR*8;
+static unsigned int khugepaged_pages_to_scan __read_mostly;
 static unsigned int khugepaged_pages_collapsed;
 static unsigned int khugepaged_full_scans;
 static unsigned int khugepaged_scan_sleep_millisecs __read_mostly = 10000;
@@ -60,7 +60,7 @@  static DECLARE_WAIT_QUEUE_HEAD(khugepaged_wait);
  * it would have happened if the vma was large enough during page
  * fault.
  */
-static unsigned int khugepaged_max_ptes_none __read_mostly = HPAGE_PMD_NR-1;
+static unsigned int khugepaged_max_ptes_none __read_mostly;
 
 static int khugepaged(void *none);
 static int khugepaged_slab_init(void);
@@ -620,11 +620,14 @@  static int __init hugepage_init(void)
 	int err;
 	struct kobject *hugepage_kobj;
 
-	if (!has_transparent_hugepage()) {
+	if (!has_transparent_hugepage() || (HPAGE_PMD_ORDER > MAX_ORDER)) {
 		transparent_hugepage_flags = 0;
 		return -EINVAL;
 	}
 
+	khugepaged_pages_to_scan = HPAGE_PMD_NR*8;
+	khugepaged_max_ptes_none = HPAGE_PMD_NR-1;
+
 	err = hugepage_init_sysfs(&hugepage_kobj);
 	if (err)
 		return err;