return err;
}
-/*
- * Update task->flags PF_MEMPOLICY bit: set iff non-default
- * mempolicy. Allows more rapid checking of this (combined perhaps
- * with other PF_* flag bits) on memory allocation hot code paths.
- *
- * If called from outside this file, the task 'p' should -only- be
- * a newly forked child not yet visible on the task list, because
- * manipulating the task flags of a visible task is not safe.
- *
- * The above limitation is why this routine has the funny name
- * mpol_fix_fork_child_flag().
- *
- * It is also safe to call this with a task pointer of current,
- * which the static wrapper mpol_set_task_struct_flag() does,
- * for use within this file.
- */
-
-void mpol_fix_fork_child_flag(struct task_struct *p)
-{
- if (p->mempolicy)
- p->flags |= PF_MEMPOLICY;
- else
- p->flags &= ~PF_MEMPOLICY;
-}
-
-static void mpol_set_task_struct_flag(void)
-{
- mpol_fix_fork_child_flag(current);
-}
-
/* Set the process memory policy */
static long do_set_mempolicy(unsigned short mode, unsigned short flags,
nodemask_t *nodes)
}
old = current->mempolicy;
current->mempolicy = new;
- mpol_set_task_struct_flag();
if (new && new->mode == MPOL_INTERLEAVE &&
nodes_weight(new->v.nodes))
current->il_next = first_node(new->v.nodes);
#ifdef CONFIG_COMPAT
-asmlinkage long compat_sys_get_mempolicy(int __user *policy,
- compat_ulong_t __user *nmask,
- compat_ulong_t maxnode,
- compat_ulong_t addr, compat_ulong_t flags)
+COMPAT_SYSCALL_DEFINE5(get_mempolicy, int __user *, policy,
+ compat_ulong_t __user *, nmask,
+ compat_ulong_t, maxnode,
+ compat_ulong_t, addr, compat_ulong_t, flags)
{
long err;
unsigned long __user *nm = NULL;
return err;
}
-asmlinkage long compat_sys_set_mempolicy(int mode, compat_ulong_t __user *nmask,
- compat_ulong_t maxnode)
+COMPAT_SYSCALL_DEFINE3(set_mempolicy, int, mode, compat_ulong_t __user *, nmask,
+ compat_ulong_t, maxnode)
{
long err = 0;
unsigned long __user *nm = NULL;
return sys_set_mempolicy(mode, nm, nr_bits+1);
}
-asmlinkage long compat_sys_mbind(compat_ulong_t start, compat_ulong_t len,
- compat_ulong_t mode, compat_ulong_t __user *nmask,
- compat_ulong_t maxnode, compat_ulong_t flags)
+COMPAT_SYSCALL_DEFINE6(mbind, compat_ulong_t, start, compat_ulong_t, len,
+ compat_ulong_t, mode, compat_ulong_t __user *, nmask,
+ compat_ulong_t, maxnode, compat_ulong_t, flags)
{
long err = 0;
unsigned long __user *nm = NULL;
/*
* Depending on the memory policy provide a node from which to allocate the
* next slab entry.
- * @policy must be protected by freeing by the caller. If @policy is
- * the current task's mempolicy, this protection is implicit, as only the
- * task can change it's policy. The system default policy requires no
- * such protection.
*/
-unsigned slab_node(void)
+unsigned int mempolicy_slab_node(void)
{
struct mempolicy *policy;
+ int node = numa_mem_id();
if (in_interrupt())
- return numa_node_id();
+ return node;
policy = current->mempolicy;
if (!policy || policy->flags & MPOL_F_LOCAL)
- return numa_node_id();
+ return node;
switch (policy->mode) {
case MPOL_PREFERRED:
struct zonelist *zonelist;
struct zone *zone;
enum zone_type highest_zoneidx = gfp_zone(GFP_KERNEL);
- zonelist = &NODE_DATA(numa_node_id())->node_zonelists[0];
+ zonelist = &NODE_DATA(node)->node_zonelists[0];
(void)first_zones_zonelist(zonelist, highest_zoneidx,
&policy->v.nodes,
&zone);
- return zone ? zone->node : numa_node_id();
+ return zone ? zone->node : node;
}
default:
* If the effective policy is 'BIND, returns a pointer to the mempolicy's
* @nodemask for filtering the zonelist.
*
- * Must be protected by get_mems_allowed()
+ * Must be protected by read_mems_allowed_begin()
*/
struct zonelist *huge_zonelist(struct vm_area_struct *vma, unsigned long addr,
gfp_t gfp_flags, struct mempolicy **mpol,
retry_cpuset:
pol = get_vma_policy(current, vma, addr);
- cpuset_mems_cookie = get_mems_allowed();
+ cpuset_mems_cookie = read_mems_allowed_begin();
if (unlikely(pol->mode == MPOL_INTERLEAVE)) {
unsigned nid;
nid = interleave_nid(pol, vma, addr, PAGE_SHIFT + order);
mpol_cond_put(pol);
page = alloc_page_interleave(gfp, order, nid);
- if (unlikely(!put_mems_allowed(cpuset_mems_cookie) && !page))
+ if (unlikely(!page && read_mems_allowed_retry(cpuset_mems_cookie)))
goto retry_cpuset;
return page;
policy_nodemask(gfp, pol));
if (unlikely(mpol_needs_cond_ref(pol)))
__mpol_put(pol);
- if (unlikely(!put_mems_allowed(cpuset_mems_cookie) && !page))
+ if (unlikely(!page && read_mems_allowed_retry(cpuset_mems_cookie)))
goto retry_cpuset;
return page;
}
pol = &default_policy;
retry_cpuset:
- cpuset_mems_cookie = get_mems_allowed();
+ cpuset_mems_cookie = read_mems_allowed_begin();
/*
* No reference counting needed for current->mempolicy
policy_zonelist(gfp, pol, numa_node_id()),
policy_nodemask(gfp, pol));
- if (unlikely(!put_mems_allowed(cpuset_mems_cookie) && !page))
+ if (unlikely(!page && read_mems_allowed_retry(cpuset_mems_cookie)))
goto retry_cpuset;
return page;
kmem_cache_free(sn_cache, n);
}
-#ifdef CONFIG_NUMA_BALANCING
-static bool numa_migrate_deferred(struct task_struct *p, int last_cpupid)
-{
- /* Never defer a private fault */
- if (cpupid_match_pid(p, last_cpupid))
- return false;
-
- if (p->numa_migrate_deferred) {
- p->numa_migrate_deferred--;
- return true;
- }
- return false;
-}
-
-static inline void defer_numa_migrate(struct task_struct *p)
-{
- p->numa_migrate_deferred = sysctl_numa_balancing_migrate_deferred;
-}
-#else
-static inline bool numa_migrate_deferred(struct task_struct *p, int last_cpupid)
-{
- return false;
-}
-
-static inline void defer_numa_migrate(struct task_struct *p)
-{
-}
-#endif /* CONFIG_NUMA_BALANCING */
-
/**
* mpol_misplaced - check whether current page node is valid in policy
*
/* Migrate the page towards the node whose CPU is referencing it */
if (pol->flags & MPOL_F_MORON) {
- int last_cpupid;
- int this_cpupid;
-
polnid = thisnid;
- this_cpupid = cpu_pid_to_cpupid(thiscpu, current->pid);
-
- /*
- * Multi-stage node selection is used in conjunction
- * with a periodic migration fault to build a temporal
- * task<->page relation. By using a two-stage filter we
- * remove short/unlikely relations.
- *
- * Using P(p) ~ n_p / n_t as per frequentist
- * probability, we can equate a task's usage of a
- * particular page (n_p) per total usage of this
- * page (n_t) (in a given time-span) to a probability.
- *
- * Our periodic faults will sample this probability and
- * getting the same result twice in a row, given these
- * samples are fully independent, is then given by
- * P(n)^2, provided our sample period is sufficiently
- * short compared to the usage pattern.
- *
- * This quadric squishes small probabilities, making
- * it less likely we act on an unlikely task<->page
- * relation.
- */
- last_cpupid = page_cpupid_xchg_last(page, this_cpupid);
- if (!cpupid_pid_unset(last_cpupid) && cpupid_to_nid(last_cpupid) != thisnid) {
-
- /* See sysctl_numa_balancing_migrate_deferred comment */
- if (!cpupid_match_pid(current, last_cpupid))
- defer_numa_migrate(current);
- goto out;
- }
-
- /*
- * The quadratic filter above reduces extraneous migration
- * of shared pages somewhat. This code reduces it even more,
- * reducing the overhead of page migrations of shared pages.
- * This makes workloads with shared pages rely more on
- * "move task near its memory", and less on "move memory
- * towards its task", which is exactly what we want.
- */
- if (numa_migrate_deferred(current, last_cpupid))
+ if (!should_numa_migrate_memory(current, page, curnid, thiscpu))
goto out;
}
projects / linux.git / blobdiff