https://github.com/torvalds/linux
Tip revision: 55922c9d1b84b89cb946c777fddccb3247e7df2c authored by Linus Torvalds on 30 May 2011, 00:43:36 UTC
Linux 3.0-rc1
Linux 3.0-rc1
Tip revision: 55922c9
mempolicy.h
#ifndef _LINUX_MEMPOLICY_H
#define _LINUX_MEMPOLICY_H 1
#include <linux/errno.h>
/*
* NUMA memory policies for Linux.
* Copyright 2003,2004 Andi Kleen SuSE Labs
*/
/*
* Both the MPOL_* mempolicy mode and the MPOL_F_* optional mode flags are
* passed by the user to either set_mempolicy() or mbind() in an 'int' actual.
* The MPOL_MODE_FLAGS macro determines the legal set of optional mode flags.
*/
/* Policies */
enum {
MPOL_DEFAULT,
MPOL_PREFERRED,
MPOL_BIND,
MPOL_INTERLEAVE,
MPOL_MAX, /* always last member of enum */
};
enum mpol_rebind_step {
MPOL_REBIND_ONCE, /* do rebind work at once(not by two step) */
MPOL_REBIND_STEP1, /* first step(set all the newly nodes) */
MPOL_REBIND_STEP2, /* second step(clean all the disallowed nodes)*/
MPOL_REBIND_NSTEP,
};
/* Flags for set_mempolicy */
#define MPOL_F_STATIC_NODES (1 << 15)
#define MPOL_F_RELATIVE_NODES (1 << 14)
/*
* MPOL_MODE_FLAGS is the union of all possible optional mode flags passed to
* either set_mempolicy() or mbind().
*/
#define MPOL_MODE_FLAGS (MPOL_F_STATIC_NODES | MPOL_F_RELATIVE_NODES)
/* Flags for get_mempolicy */
#define MPOL_F_NODE (1<<0) /* return next IL mode instead of node mask */
#define MPOL_F_ADDR (1<<1) /* look up vma using address */
#define MPOL_F_MEMS_ALLOWED (1<<2) /* return allowed memories */
/* Flags for mbind */
#define MPOL_MF_STRICT (1<<0) /* Verify existing pages in the mapping */
#define MPOL_MF_MOVE (1<<1) /* Move pages owned by this process to conform to mapping */
#define MPOL_MF_MOVE_ALL (1<<2) /* Move every page to conform to mapping */
#define MPOL_MF_INTERNAL (1<<3) /* Internal flags start here */
/*
* Internal flags that share the struct mempolicy flags word with
* "mode flags". These flags are allocated from bit 0 up, as they
* are never OR'ed into the mode in mempolicy API arguments.
*/
#define MPOL_F_SHARED (1 << 0) /* identify shared policies */
#define MPOL_F_LOCAL (1 << 1) /* preferred local allocation */
#define MPOL_F_REBINDING (1 << 2) /* identify policies in rebinding */
#ifdef __KERNEL__
#include <linux/mmzone.h>
#include <linux/slab.h>
#include <linux/rbtree.h>
#include <linux/spinlock.h>
#include <linux/nodemask.h>
#include <linux/pagemap.h>
struct mm_struct;
#ifdef CONFIG_NUMA
/*
* Describe a memory policy.
*
* A mempolicy can be either associated with a process or with a VMA.
* For VMA related allocations the VMA policy is preferred, otherwise
* the process policy is used. Interrupts ignore the memory policy
* of the current process.
*
* Locking policy for interlave:
* In process context there is no locking because only the process accesses
* its own state. All vma manipulation is somewhat protected by a down_read on
* mmap_sem.
*
* Freeing policy:
* Mempolicy objects are reference counted. A mempolicy will be freed when
* mpol_put() decrements the reference count to zero.
*
* Duplicating policy objects:
* mpol_dup() allocates a new mempolicy and copies the specified mempolicy
* to the new storage. The reference count of the new object is initialized
* to 1, representing the caller of mpol_dup().
*/
struct mempolicy {
atomic_t refcnt;
unsigned short mode; /* See MPOL_* above */
unsigned short flags; /* See set_mempolicy() MPOL_F_* above */
union {
short preferred_node; /* preferred */
nodemask_t nodes; /* interleave/bind */
/* undefined for default */
} v;
union {
nodemask_t cpuset_mems_allowed; /* relative to these nodes */
nodemask_t user_nodemask; /* nodemask passed by user */
} w;
};
/*
* Support for managing mempolicy data objects (clone, copy, destroy)
* The default fast path of a NULL MPOL_DEFAULT policy is always inlined.
*/
extern void __mpol_put(struct mempolicy *pol);
static inline void mpol_put(struct mempolicy *pol)
{
if (pol)
__mpol_put(pol);
}
/*
* Does mempolicy pol need explicit unref after use?
* Currently only needed for shared policies.
*/
static inline int mpol_needs_cond_ref(struct mempolicy *pol)
{
return (pol && (pol->flags & MPOL_F_SHARED));
}
static inline void mpol_cond_put(struct mempolicy *pol)
{
if (mpol_needs_cond_ref(pol))
__mpol_put(pol);
}
extern struct mempolicy *__mpol_cond_copy(struct mempolicy *tompol,
struct mempolicy *frompol);
static inline struct mempolicy *mpol_cond_copy(struct mempolicy *tompol,
struct mempolicy *frompol)
{
if (!frompol)
return frompol;
return __mpol_cond_copy(tompol, frompol);
}
extern struct mempolicy *__mpol_dup(struct mempolicy *pol);
static inline struct mempolicy *mpol_dup(struct mempolicy *pol)
{
if (pol)
pol = __mpol_dup(pol);
return pol;
}
#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)
{
if (pol)
atomic_inc(&pol->refcnt);
}
extern int __mpol_equal(struct mempolicy *a, struct mempolicy *b);
static inline int mpol_equal(struct mempolicy *a, struct mempolicy *b)
{
if (a == b)
return 1;
return __mpol_equal(a, b);
}
/*
* Tree of shared policies for a shared memory region.
* Maintain the policies in a pseudo mm that contains vmas. The vmas
* carry the policy. As a special twist the pseudo mm is indexed in pages, not
* bytes, so that we can work with shared memory segments bigger than
* unsigned long.
*/
struct sp_node {
struct rb_node nd;
unsigned long start, end;
struct mempolicy *policy;
};
struct shared_policy {
struct rb_root root;
spinlock_t lock;
};
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,
struct mempolicy *new);
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_vma_policy(struct task_struct *tsk,
struct vm_area_struct *vma, unsigned long addr);
extern void numa_default_policy(void);
extern void numa_policy_init(void);
extern void mpol_rebind_task(struct task_struct *tsk, const nodemask_t *new,
enum mpol_rebind_step step);
extern void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new);
extern void mpol_fix_fork_child_flag(struct task_struct *p);
extern struct zonelist *huge_zonelist(struct vm_area_struct *vma,
unsigned long addr, gfp_t gfp_flags,
struct mempolicy **mpol, nodemask_t **nodemask);
extern bool init_nodemask_of_mempolicy(nodemask_t *mask);
extern bool mempolicy_nodemask_intersects(struct task_struct *tsk,
const nodemask_t *mask);
extern unsigned slab_node(struct mempolicy *policy);
extern enum zone_type policy_zone;
static inline void check_highest_zone(enum zone_type k)
{
if (k > policy_zone && k != ZONE_MOVABLE)
policy_zone = k;
}
int do_migrate_pages(struct mm_struct *mm,
const nodemask_t *from_nodes, const nodemask_t *to_nodes, int flags);
#ifdef CONFIG_TMPFS
extern int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context);
#endif
extern int mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol,
int no_context);
/* Check if a vma is migratable */
static inline int vma_migratable(struct vm_area_struct *vma)
{
if (vma->vm_flags & (VM_IO|VM_HUGETLB|VM_PFNMAP|VM_RESERVED))
return 0;
/*
* Migration allocates pages in the highest zone. If we cannot
* do so then migration (at least from node to node) is not
* possible.
*/
if (vma->vm_file &&
gfp_zone(mapping_gfp_mask(vma->vm_file->f_mapping))
< policy_zone)
return 0;
return 1;
}
#else
struct mempolicy {};
static inline int mpol_equal(struct mempolicy *a, struct mempolicy *b)
{
return 1;
}
static inline void mpol_put(struct mempolicy *p)
{
}
static inline void mpol_cond_put(struct mempolicy *pol)
{
}
static inline struct mempolicy *mpol_cond_copy(struct mempolicy *to,
struct mempolicy *from)
{
return from;
}
static inline void mpol_get(struct mempolicy *pol)
{
}
static inline struct mempolicy *mpol_dup(struct mempolicy *old)
{
return NULL;
}
struct shared_policy {};
static inline int mpol_set_shared_policy(struct shared_policy *info,
struct vm_area_struct *vma,
struct mempolicy *new)
{
return -EINVAL;
}
static inline void mpol_shared_policy_init(struct shared_policy *sp,
struct mempolicy *mpol)
{
}
static inline void mpol_free_shared_policy(struct shared_policy *p)
{
}
static inline struct mempolicy *
mpol_shared_policy_lookup(struct shared_policy *sp, unsigned long idx)
{
return NULL;
}
#define vma_policy(vma) NULL
#define vma_set_policy(vma, pol) do {} while(0)
static inline void numa_policy_init(void)
{
}
static inline void numa_default_policy(void)
{
}
static inline void mpol_rebind_task(struct task_struct *tsk,
const nodemask_t *new,
enum mpol_rebind_step step)
{
}
static inline void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new)
{
}
static inline void mpol_fix_fork_child_flag(struct task_struct *p)
{
}
static inline struct zonelist *huge_zonelist(struct vm_area_struct *vma,
unsigned long addr, gfp_t gfp_flags,
struct mempolicy **mpol, nodemask_t **nodemask)
{
*mpol = NULL;
*nodemask = NULL;
return node_zonelist(0, gfp_flags);
}
static inline bool init_nodemask_of_mempolicy(nodemask_t *m)
{
return false;
}
static inline bool mempolicy_nodemask_intersects(struct task_struct *tsk,
const nodemask_t *mask)
{
return false;
}
static inline int do_migrate_pages(struct mm_struct *mm,
const nodemask_t *from_nodes,
const nodemask_t *to_nodes, int flags)
{
return 0;
}
static inline void check_highest_zone(int k)
{
}
#ifdef CONFIG_TMPFS
static inline int mpol_parse_str(char *str, struct mempolicy **mpol,
int no_context)
{
return 1; /* error */
}
#endif
static inline int mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol,
int no_context)
{
return 0;
}
#endif /* CONFIG_NUMA */
#endif /* __KERNEL__ */
#endif