Commit 74d2c3a0 authored by Oleg Nesterov's avatar Oleg Nesterov Committed by Linus Torvalds
Browse files

mempolicy: introduce __get_vma_policy(), export get_task_policy() 



Extract the code which looks for vma's policy from get_vma_policy()
into the new helper, __get_vma_policy(). Export get_task_policy().

Signed-off-by: default avatarOleg Nesterov <oleg@redhat.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 6b6482bb

include/linux/mempolicy.h

+3 −0
Original line number Diff line number Diff line
@@ -134,6 +134,9 @@ void mpol_free_shared_policy(struct shared_policy *p); 
struct mempolicy *mpol_shared_policy_lookup(struct shared_policy *sp,

					    unsigned long idx);



struct mempolicy *get_task_policy(struct task_struct *p);

struct mempolicy *__get_vma_policy(struct vm_area_struct *vma,

		unsigned long addr);

struct mempolicy *get_vma_policy(struct task_struct *tsk,

		struct vm_area_struct *vma, unsigned long addr);

bool vma_policy_mof(struct vm_area_struct *vma);

mm/mempolicy.c

+26 −18
Original line number Diff line number Diff line
@@ -123,7 +123,7 @@ static struct mempolicy default_policy = { 


static struct mempolicy preferred_node_policy[MAX_NUMNODES];



static struct mempolicy *get_task_policy(struct task_struct *p)

struct mempolicy *get_task_policy(struct task_struct *p)

{

	struct mempolicy *pol = p->mempolicy;

	int node;
@@ -1603,23 +1603,8 @@ COMPAT_SYSCALL_DEFINE6(mbind, compat_ulong_t, start, compat_ulong_t, len, 


#endif



/*

 * get_vma_policy(@task, @vma, @addr)

 * @task: task for fallback if vma policy == default

 * @vma: virtual memory area whose policy is sought

 * @addr: address in @vma for shared policy lookup

 *

 * Returns effective policy for a VMA at specified address.

 * Falls back to @task or system default policy, as necessary.

 * Current or other task's task mempolicy and non-shared vma policies must be

 * protected by task_lock(task) by the caller.

 * Shared policies [those marked as MPOL_F_SHARED] require an extra reference

 * count--added by the get_policy() vm_op, as appropriate--to protect against

 * freeing by another task.  It is the caller's responsibility to free the

 * extra reference for shared policies.

 */

struct mempolicy *get_vma_policy(struct task_struct *task,

		struct vm_area_struct *vma, unsigned long addr)

struct mempolicy *__get_vma_policy(struct vm_area_struct *vma,

						unsigned long addr)

{

	struct mempolicy *pol = NULL;
@@ -1640,6 +1625,29 @@ struct mempolicy *get_vma_policy(struct task_struct *task, 
		}

	}



	return pol;

}



/*

 * get_vma_policy(@task, @vma, @addr)

 * @task: task for fallback if vma policy == default

 * @vma: virtual memory area whose policy is sought

 * @addr: address in @vma for shared policy lookup

 *

 * Returns effective policy for a VMA at specified address.

 * Falls back to @task or system default policy, as necessary.

 * Current or other task's task mempolicy and non-shared vma policies must be

 * protected by task_lock(task) by the caller.

 * Shared policies [those marked as MPOL_F_SHARED] require an extra reference

 * count--added by the get_policy() vm_op, as appropriate--to protect against

 * freeing by another task.  It is the caller's responsibility to free the

 * extra reference for shared policies.

 */

struct mempolicy *get_vma_policy(struct task_struct *task,

		struct vm_area_struct *vma, unsigned long addr)

{

	struct mempolicy *pol = __get_vma_policy(vma, addr);



	if (!pol)

		pol = get_task_policy(task);

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