[patch -mm 2/2] mempolicy: use default_policy mode instead of MPOL_DEFAULT

[David Rientjes <rientjes@google.com>]

default_policy is defined in mm/mempolicy.c as the default system policy:

	struct mempolicy default_policy = {
		.refcnt = ATOMIC_INIT(1),
		.policy = MPOL_DEFAULT,
	};

So instead of checking for comparisons against a mempolicy's mode to
MPOL_DEFAULT or falling back stricly to MPOL_DEFAULT throughout the code,
we should use the mode that is defined in this struct.

Cc: Paul Jackson <pj@sgi.com>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: David Rientjes <rientjes@google.com>
---
 mm/mempolicy.c |   12 ++++++------
 1 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -185,7 +185,7 @@ static struct mempolicy *mpol_new(unsigned short mode, unsigned short flags,
 			return ERR_PTR(-EINVAL);
 	} else if (nodes && nodes_empty(*nodes))
 		return ERR_PTR(-EINVAL);
-	if (mode == MPOL_DEFAULT)
+	if (mode == default_policy.policy)
 		return NULL;
 	policy = kmem_cache_alloc(policy_cache, GFP_KERNEL);
 	if (!policy)
@@ -1232,7 +1232,7 @@ static struct mempolicy * get_vma_policy(struct task_struct *task,
 			pol = vma->vm_ops->get_policy(vma, addr);
 			shared_pol = 1;	/* if pol non-NULL, add ref below */
 		} else if (vma->vm_policy &&
-				vma->vm_policy->policy != MPOL_DEFAULT)
+			   vma->vm_policy->policy != default_policy.policy)
 			pol = vma->vm_policy;
 	}
 	if (!pol)
@@ -1588,7 +1588,7 @@ void __mpol_free(struct mempolicy *p)
 {
 	if (!atomic_dec_and_test(&p->refcnt))
 		return;
-	p->policy = MPOL_DEFAULT;
+	p->policy = default_policy.policy;
 	kmem_cache_free(policy_cache, p);
 }
 
@@ -1752,10 +1752,10 @@ void mpol_shared_policy_init(struct shared_policy *info, unsigned short policy,
 	info->root = RB_ROOT;
 	spin_lock_init(&info->lock);
 
-	if (policy != MPOL_DEFAULT) {
+	if (policy != default_policy.policy) {
 		struct mempolicy *newpol;
 
-		/* Falls back to MPOL_DEFAULT on any error */
+		/* Falls back to default_policy on any error */
 		newpol = mpol_new(policy, flags, policy_nodes);
 		if (!IS_ERR(newpol)) {
 			/* Create pseudo-vma that contains just the policy */
@@ -1860,7 +1860,7 @@ void __init numa_policy_init(void)
 /* Reset policy of current process to default */
 void numa_default_policy(void)
 {
-	do_set_mempolicy(MPOL_DEFAULT, 0, NULL);
+	do_set_mempolicy(default_policy.policy, 0, NULL);
 }
 
 /*