mm: do not use mm->nr_pmds on !MMU configurations

mm->nr_pmds doesn't make sense on !MMU configurations

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/include/linux/mm.h b/include/linux/mm.h
index af4ff88a11e0899e88778edf4b6bf142acb37d70..bd52e2f140276d9aa22caf7753463f1de2960d85 100644 (file)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1447,13 +1447,15 @@ static inline int __pud_alloc(struct mm_struct *mm, pgd_t *pgd,
 int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address);
 #endif
 
-#ifdef __PAGETABLE_PMD_FOLDED
+#if defined(__PAGETABLE_PMD_FOLDED) || !defined(CONFIG_MMU)
 static inline int __pmd_alloc(struct mm_struct *mm, pud_t *pud,
                                                unsigned long address)
 {
        return 0;
 }
 
+static inline void mm_nr_pmds_init(struct mm_struct *mm) {}
+
 static inline unsigned long mm_nr_pmds(struct mm_struct *mm)
 {
        return 0;
@@ -1465,6 +1467,11 @@ static inline void mm_dec_nr_pmds(struct mm_struct *mm) {}
 #else
 int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address);
 
+static inline void mm_nr_pmds_init(struct mm_struct *mm)
+{
+       atomic_long_set(&mm->nr_pmds, 0);
+}
+
 static inline unsigned long mm_nr_pmds(struct mm_struct *mm)
 {
        return atomic_long_read(&mm->nr_pmds);

diff --git a/kernel/fork.c b/kernel/fork.c
index 66e19c251581d1ddf52090bc37a23c645d19dd80..cf65139615a0d38e3fef37ee3a6e2e270c01ccaf 100644 (file)
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -555,9 +555,7 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p)
        INIT_LIST_HEAD(&mm->mmlist);
        mm->core_state = NULL;
        atomic_long_set(&mm->nr_ptes, 0);
-#ifndef __PAGETABLE_PMD_FOLDED
-       atomic_long_set(&mm->nr_pmds, 0);
-#endif
+       mm_nr_pmds_init(mm);
        mm->map_count = 0;
        mm->locked_vm = 0;
        mm->pinned_vm = 0;