mm: mempolicy: turn vma_set_policy() into vma_dup_policy()
Simple cleanup. Every user of vma_set_policy() does the same work, this
looks a bit annoying imho. And the new trivial helper which does
mpol_dup() + vma_set_policy() to simplify the callers.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/mempolicy.h b/include/linux/mempolicy.h
index 0d7df39..b2f8977 100644
--- a/include/linux/mempolicy.h
+++ b/include/linux/mempolicy.h
@@ -91,7 +91,6 @@
}
#define vma_policy(vma) ((vma)->vm_policy)
-#define vma_set_policy(vma, pol) ((vma)->vm_policy = (pol))
static inline void mpol_get(struct mempolicy *pol)
{
@@ -126,6 +125,7 @@
spinlock_t lock;
};
+int vma_dup_policy(struct vm_area_struct *src, struct vm_area_struct *dst);
void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol);
int mpol_set_shared_policy(struct shared_policy *info,
struct vm_area_struct *vma,
@@ -240,7 +240,12 @@
}
#define vma_policy(vma) NULL
-#define vma_set_policy(vma, pol) do {} while(0)
+
+static inline int
+vma_dup_policy(struct vm_area_struct *src, struct vm_area_struct *dst)
+{
+ return 0;
+}
static inline void numa_policy_init(void)
{
diff --git a/kernel/fork.c b/kernel/fork.c
index 84703db..81ccb4f 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -351,7 +351,6 @@
struct rb_node **rb_link, *rb_parent;
int retval;
unsigned long charge;
- struct mempolicy *pol;
uprobe_start_dup_mmap();
down_write(&oldmm->mmap_sem);
@@ -400,11 +399,9 @@
goto fail_nomem;
*tmp = *mpnt;
INIT_LIST_HEAD(&tmp->anon_vma_chain);
- pol = mpol_dup(vma_policy(mpnt));
- retval = PTR_ERR(pol);
- if (IS_ERR(pol))
+ retval = vma_dup_policy(mpnt, tmp);
+ if (retval)
goto fail_nomem_policy;
- vma_set_policy(tmp, pol);
tmp->vm_mm = mm;
if (anon_vma_fork(tmp, mpnt))
goto fail_nomem_anon_vma_fork;
@@ -472,7 +469,7 @@
uprobe_end_dup_mmap();
return retval;
fail_nomem_anon_vma_fork:
- mpol_put(pol);
+ mpol_put(vma_policy(tmp));
fail_nomem_policy:
kmem_cache_free(vm_area_cachep, tmp);
fail_nomem:
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 4baf12e..6b1d426 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -2065,6 +2065,16 @@
}
EXPORT_SYMBOL(alloc_pages_current);
+int vma_dup_policy(struct vm_area_struct *src, struct vm_area_struct *dst)
+{
+ struct mempolicy *pol = mpol_dup(vma_policy(src));
+
+ if (IS_ERR(pol))
+ return PTR_ERR(pol);
+ dst->vm_policy = pol;
+ return 0;
+}
+
/*
* If mpol_dup() sees current->cpuset == cpuset_being_rebound, then it
* rebinds the mempolicy its copying by calling mpol_rebind_policy()
diff --git a/mm/mmap.c b/mm/mmap.c
index f9c97d1..14f6bb4 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2380,7 +2380,6 @@
static int __split_vma(struct mm_struct * mm, struct vm_area_struct * vma,
unsigned long addr, int new_below)
{
- struct mempolicy *pol;
struct vm_area_struct *new;
int err = -ENOMEM;
@@ -2404,12 +2403,9 @@
new->vm_pgoff += ((addr - vma->vm_start) >> PAGE_SHIFT);
}
- pol = mpol_dup(vma_policy(vma));
- if (IS_ERR(pol)) {
- err = PTR_ERR(pol);
+ err = vma_dup_policy(vma, new);
+ if (err)
goto out_free_vma;
- }
- vma_set_policy(new, pol);
if (anon_vma_clone(new, vma))
goto out_free_mpol;
@@ -2437,7 +2433,7 @@
fput(new->vm_file);
unlink_anon_vmas(new);
out_free_mpol:
- mpol_put(pol);
+ mpol_put(vma_policy(new));
out_free_vma:
kmem_cache_free(vm_area_cachep, new);
out_err:
@@ -2780,7 +2776,6 @@
struct mm_struct *mm = vma->vm_mm;
struct vm_area_struct *new_vma, *prev;
struct rb_node **rb_link, *rb_parent;
- struct mempolicy *pol;
bool faulted_in_anon_vma = true;
/*
@@ -2825,10 +2820,8 @@
new_vma->vm_start = addr;
new_vma->vm_end = addr + len;
new_vma->vm_pgoff = pgoff;
- pol = mpol_dup(vma_policy(vma));
- if (IS_ERR(pol))
+ if (vma_dup_policy(vma, new_vma))
goto out_free_vma;
- vma_set_policy(new_vma, pol);
INIT_LIST_HEAD(&new_vma->anon_vma_chain);
if (anon_vma_clone(new_vma, vma))
goto out_free_mempol;
@@ -2843,7 +2836,7 @@
return new_vma;
out_free_mempol:
- mpol_put(pol);
+ mpol_put(vma_policy(new_vma));
out_free_vma:
kmem_cache_free(vm_area_cachep, new_vma);
return NULL;