diff options
Diffstat (limited to 'include/linux/mempolicy.h')
-rw-r--r-- | include/linux/mempolicy.h | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/include/linux/mempolicy.h b/include/linux/mempolicy.h new file mode 100644 index 000000000000..8480aef10e62 --- /dev/null +++ b/include/linux/mempolicy.h @@ -0,0 +1,229 @@ +#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 + */ + +/* Policies */ +#define MPOL_DEFAULT 0 +#define MPOL_PREFERRED 1 +#define MPOL_BIND 2 +#define MPOL_INTERLEAVE 3 + +#define MPOL_MAX MPOL_INTERLEAVE + +/* Flags for get_mem_policy */ +#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 */ + +/* Flags for mbind */ +#define MPOL_MF_STRICT (1<<0) /* Verify existing pages in the mapping */ + +#ifdef __KERNEL__ + +#include <linux/config.h> +#include <linux/mmzone.h> +#include <linux/bitmap.h> +#include <linux/slab.h> +#include <linux/rbtree.h> +#include <linux/spinlock.h> + +struct vm_area_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. For allocating in the interleave policy the page_table_lock + * must be also aquired to protect il_next. + * + * Freeing policy: + * When policy is MPOL_BIND v.zonelist is kmalloc'ed and must be kfree'd. + * All other policies don't have any external state. mpol_free() handles this. + * + * Copying policy objects: + * For MPOL_BIND the zonelist must be always duplicated. mpol_clone() does this. + */ +struct mempolicy { + atomic_t refcnt; + short policy; /* See MPOL_* above */ + union { + struct zonelist *zonelist; /* bind */ + short preferred_node; /* preferred */ + DECLARE_BITMAP(nodes, MAX_NUMNODES); /* interleave */ + /* undefined for default */ + } v; +}; + +/* + * 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_free(struct mempolicy *pol); +static inline void mpol_free(struct mempolicy *pol) +{ + if (pol) + __mpol_free(pol); +} + +extern struct mempolicy *__mpol_copy(struct mempolicy *pol); +static inline struct mempolicy *mpol_copy(struct mempolicy *pol) +{ + if (pol) + pol = __mpol_copy(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); +} +#define vma_mpol_equal(a,b) mpol_equal(vma_policy(a), vma_policy(b)) + +/* Could later add inheritance of the process policy here. */ + +#define mpol_set_vma_default(vma) ((vma)->vm_policy = NULL) + +/* + * Hugetlb policy. i386 hugetlb so far works with node numbers + * instead of zone lists, so give it special interfaces for now. + */ +extern int mpol_first_node(struct vm_area_struct *vma, unsigned long addr); +extern int mpol_node_valid(int nid, struct vm_area_struct *vma, + unsigned long addr); + +/* + * 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; +}; + +static inline void mpol_shared_policy_init(struct shared_policy *info) +{ + info->root = RB_ROOT; + spin_lock_init(&info->lock); +} + +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); + +extern void numa_default_policy(void); +extern void numa_policy_init(void); + +#else + +struct mempolicy {}; + +static inline int mpol_equal(struct mempolicy *a, struct mempolicy *b) +{ + return 1; +} +#define vma_mpol_equal(a,b) 1 + +#define mpol_set_vma_default(vma) do {} while(0) + +static inline void mpol_free(struct mempolicy *p) +{ +} + +static inline void mpol_get(struct mempolicy *pol) +{ +} + +static inline struct mempolicy *mpol_copy(struct mempolicy *old) +{ + return NULL; +} + +static inline int mpol_first_node(struct vm_area_struct *vma, unsigned long a) +{ + return numa_node_id(); +} + +static inline int +mpol_node_valid(int nid, struct vm_area_struct *vma, unsigned long a) +{ + return 1; +} + +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 *info) +{ +} + +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) +{ +} + +#endif /* CONFIG_NUMA */ +#endif /* __KERNEL__ */ + +#endif |