From 74d2c3a05cc6c1eef2d7236a9919036ed85ddaaf Mon Sep 17 00:00:00 2001 From: Oleg Nesterov Date: Thu, 9 Oct 2014 15:27:50 -0700 Subject: [PATCH] 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: Oleg Nesterov Cc: KAMEZAWA Hiroyuki Cc: David Rientjes Cc: KOSAKI Motohiro Cc: Alexander Viro Cc: Cyrill Gorcunov Cc: "Eric W. Biederman" Cc: "Kirill A. Shutemov" Cc: Peter Zijlstra Cc: Hugh Dickins Cc: Andi Kleen Cc: Naoya Horiguchi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/mempolicy.h | 3 +++ mm/mempolicy.c | 44 +++++++++++++++++++++++---------------- 2 files changed, 29 insertions(+), 18 deletions(-) diff --git a/include/linux/mempolicy.h b/include/linux/mempolicy.h index 5e4bfcedd2ce..e1abe249892a 100644 --- a/include/linux/mempolicy.h +++ b/include/linux/mempolicy.h @@ -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); diff --git a/mm/mempolicy.c b/mm/mempolicy.c index ad27bbc757bf..4378c334e89b 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -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); -- 2.20.1