7 files changed, 170 insertions, 191 deletions

diff --git a/include/linux/cpuset.h b/include/linux/cpuset.h
index 05ea1dd7d681..a5740fc4d04b 100644
--- a/include/linux/cpuset.h
+++ b/include/linux/cpuset.h
@@ -18,7 +18,6 @@
 
 extern int number_of_cpusets;   /* How many cpusets are defined in system? */
 
-extern int cpuset_init_early(void);
 extern int cpuset_init(void);
 extern void cpuset_init_smp(void);
 extern void cpuset_cpus_allowed(struct task_struct *p, struct cpumask *mask);
@@ -27,7 +26,6 @@ extern void cpuset_cpus_allowed_locked(struct task_struct *p,
 extern nodemask_t cpuset_mems_allowed(struct task_struct *p);
 #define cpuset_current_mems_allowed (current->mems_allowed)
 void cpuset_init_current_mems_allowed(void);
-void cpuset_update_task_memory_state(void);
 int cpuset_nodemask_valid_mems_allowed(nodemask_t *nodemask);
 
 extern int __cpuset_node_allowed_softwall(int node, gfp_t gfp_mask);
@@ -92,9 +90,13 @@ extern void rebuild_sched_domains(void);
 
 extern void cpuset_print_task_mems_allowed(struct task_struct *p);
 
+static inline void set_mems_allowed(nodemask_t nodemask)
+{
+        current->mems_allowed = nodemask;
+}
+
 #else /* !CONFIG_CPUSETS */
 
-static inline int cpuset_init_early(void) { return 0; }
 static inline int cpuset_init(void) { return 0; }
 static inline void cpuset_init_smp(void) {}
 
@@ -116,7 +118,6 @@ static inline nodemask_t cpuset_mems_allowed(struct task_struct *p)
 
 #define cpuset_current_mems_allowed (node_states[N_HIGH_MEMORY])
 static inline void cpuset_init_current_mems_allowed(void) {}
-static inline void cpuset_update_task_memory_state(void) {}
 
 static inline int cpuset_nodemask_valid_mems_allowed(nodemask_t *nodemask)
 {
@@ -188,6 +189,10 @@ static inline void cpuset_print_task_mems_allowed(struct task_struct *p)
 {
 }
 
+static inline void set_mems_allowed(nodemask_t nodemask)
+{
+}
+
 #endif /* !CONFIG_CPUSETS */
 
 #endif /* _LINUX_CPUSET_H */
diff --git a/include/linux/sched.h b/include/linux/sched.h
index c900aa530070..1048bf50540a 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1318,7 +1318,8 @@ struct task_struct {
 /* Thread group tracking */
         u32 parent_exec_id;
         u32 self_exec_id;
-/* Protection of (de-)allocation: mm, files, fs, tty, keyrings */
+/* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
+ * mempolicy */
         spinlock_t alloc_lock;
 
 #ifdef CONFIG_GENERIC_HARDIRQS
@@ -1386,8 +1387,7 @@ struct task_struct {
         cputime_t acct_timexpd; /* stime + utime since last update */
 #endif
 #ifdef CONFIG_CPUSETS
-        nodemask_t mems_allowed;
-        int cpuset_mems_generation;
+        nodemask_t mems_allowed;        /* Protected by alloc_lock */
         int cpuset_mem_spread_rotor;
 #endif
 #ifdef CONFIG_CGROUPS
@@ -1410,7 +1410,7 @@ struct task_struct {
         struct list_head perf_counter_list;
 #endif
 #ifdef CONFIG_NUMA
-        struct mempolicy *mempolicy;
+        struct mempolicy *mempolicy;    /* Protected by alloc_lock */
         short il_next;
 #endif
         atomic_t fs_excl;       /* holding fs exclusive resources */
diff --git a/init/main.c b/init/main.c
index f6204f712e7c..5e0d3f047eaf 100644
--- a/init/main.c
+++ b/init/main.c
@@ -670,7 +670,6 @@ asmlinkage void __init start_kernel(void)
                 initrd_start = 0;
         }
 #endif
-        cpuset_init_early();
         page_cgroup_init();
         enable_debug_pagealloc();
         cpu_hotplug_init();
@@ -867,6 +866,11 @@ static noinline int init_post(void)
 static int __init kernel_init(void * unused)
 {
         lock_kernel();
+
+        /*
+         * init can allocate pages on any node
+         */
+        set_mems_allowed(node_possible_map);
         /*
          * init can run on any cpu.
          */
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index af5a83d52187..7e75a41bd508 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -97,12 +97,6 @@ struct cpuset {
 
         struct cpuset *parent;          /* my parent */
 
-        /*
-         * Copy of global cpuset_mems_generation as of the most
-         * recent time this cpuset changed its mems_allowed.
-         */
-        int mems_generation;
-
         struct fmeter fmeter;           /* memory_pressure filter */
 
         /* partition number for rebuild_sched_domains() */
@@ -176,27 +170,6 @@ static inline int is_spread_slab(const struct cpuset *cs)
         return test_bit(CS_SPREAD_SLAB, &cs->flags);
 }
 
-/*
- * Increment this integer everytime any cpuset changes its
- * mems_allowed value.  Users of cpusets can track this generation
- * number, and avoid having to lock and reload mems_allowed unless
- * the cpuset they're using changes generation.
- *
- * A single, global generation is needed because cpuset_attach_task() could
- * reattach a task to a different cpuset, which must not have its
- * generation numbers aliased with those of that tasks previous cpuset.
- *
- * Generations are needed for mems_allowed because one task cannot
- * modify another's memory placement.  So we must enable every task,
- * on every visit to __alloc_pages(), to efficiently check whether
- * its current->cpuset->mems_allowed has changed, requiring an update
- * of its current->mems_allowed.
- *
- * Since writes to cpuset_mems_generation are guarded by the cgroup lock
- * there is no need to mark it atomic.
- */
-static int cpuset_mems_generation;
-
 static struct cpuset top_cpuset = {
         .flags = ((1 << CS_CPU_EXCLUSIVE) | (1 << CS_MEM_EXCLUSIVE)),
 };
@@ -228,8 +201,9 @@ static struct cpuset top_cpuset = {
  * If a task is only holding callback_mutex, then it has read-only
  * access to cpusets.
  *
- * The task_struct fields mems_allowed and mems_generation may only
- * be accessed in the context of that task, so require no locks.
+ * Now, the task_struct fields mems_allowed and mempolicy may be changed
+ * by other task, we use alloc_lock in the task_struct fields to protect
+ * them.
  *
  * The cpuset_common_file_read() handlers only hold callback_mutex across
  * small pieces of code, such as when reading out possibly multi-word
@@ -349,69 +323,6 @@ static void cpuset_update_task_spread_flag(struct cpuset *cs,
                 tsk->flags &= ~PF_SPREAD_SLAB;
 }
 
-/**
- * cpuset_update_task_memory_state - update task memory placement
- *
- * If the current tasks cpusets mems_allowed changed behind our
- * backs, update current->mems_allowed, mems_generation and task NUMA
- * mempolicy to the new value.
- *
- * Task mempolicy is updated by rebinding it relative to the
- * current->cpuset if a task has its memory placement changed.
- * Do not call this routine if in_interrupt().
- *
- * Call without callback_mutex or task_lock() held.  May be
- * called with or without cgroup_mutex held.  Thanks in part to
- * 'the_top_cpuset_hack', the task's cpuset pointer will never
- * be NULL.  This routine also might acquire callback_mutex during
- * call.
- *
- * Reading current->cpuset->mems_generation doesn't need task_lock
- * to guard the current->cpuset derefence, because it is guarded
- * from concurrent freeing of current->cpuset using RCU.
- *
- * The rcu_dereference() is technically probably not needed,
- * as I don't actually mind if I see a new cpuset pointer but
- * an old value of mems_generation.  However this really only
- * matters on alpha systems using cpusets heavily.  If I dropped
- * that rcu_dereference(), it would save them a memory barrier.
- * For all other arch's, rcu_dereference is a no-op anyway, and for
- * alpha systems not using cpusets, another planned optimization,
- * avoiding the rcu critical section for tasks in the root cpuset
- * which is statically allocated, so can't vanish, will make this
- * irrelevant.  Better to use RCU as intended, than to engage in
- * some cute trick to save a memory barrier that is impossible to
- * test, for alpha systems using cpusets heavily, which might not
- * even exist.
- *
- * This routine is needed to update the per-task mems_allowed data,
- * within the tasks context, when it is trying to allocate memory
- * (in various mm/mempolicy.c routines) and notices that some other
- * task has been modifying its cpuset.
- */
-
-void cpuset_update_task_memory_state(void)
-{
-        int my_cpusets_mem_gen;
-        struct task_struct *tsk = current;
-        struct cpuset *cs;
-
-        rcu_read_lock();
-        my_cpusets_mem_gen = task_cs(tsk)->mems_generation;
-        rcu_read_unlock();
-
-        if (my_cpusets_mem_gen != tsk->cpuset_mems_generation) {
-                mutex_lock(&callback_mutex);
-                task_lock(tsk);
-                cs = task_cs(tsk); /* Maybe changed when task not locked */
-                guarantee_online_mems(cs, &tsk->mems_allowed);
-                tsk->cpuset_mems_generation = cs->mems_generation;
-                task_unlock(tsk);
-                mutex_unlock(&callback_mutex);
-                mpol_rebind_task(tsk, &tsk->mems_allowed);
-        }
-}
-
 /*
  * is_cpuset_subset(p, q) - Is cpuset p a subset of cpuset q?
  *
@@ -1017,14 +928,6 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs,
  *    other task, the task_struct mems_allowed that we are hacking
  *    is for our current task, which must allocate new pages for that
  *    migrating memory region.
- *
- *    We call cpuset_update_task_memory_state() before hacking
- *    our tasks mems_allowed, so that we are assured of being in
- *    sync with our tasks cpuset, and in particular, callbacks to
- *    cpuset_update_task_memory_state() from nested page allocations
- *    won't see any mismatch of our cpuset and task mems_generation
- *    values, so won't overwrite our hacked tasks mems_allowed
- *    nodemask.
  */
 
 static void cpuset_migrate_mm(struct mm_struct *mm, const nodemask_t *from,
@@ -1032,22 +935,37 @@ static void cpuset_migrate_mm(struct mm_struct *mm, const nodemask_t *from,
 {
         struct task_struct *tsk = current;
 
-        cpuset_update_task_memory_state();
-
-        mutex_lock(&callback_mutex);
         tsk->mems_allowed = *to;
-        mutex_unlock(&callback_mutex);
 
         do_migrate_pages(mm, from, to, MPOL_MF_MOVE_ALL);
 
-        mutex_lock(&callback_mutex);
         guarantee_online_mems(task_cs(tsk),&tsk->mems_allowed);
-        mutex_unlock(&callback_mutex);
 }
 
 /*
- * Rebind task's vmas to cpuset's new mems_allowed, and migrate pages to new
- * nodes if memory_migrate flag is set. Called with cgroup_mutex held.
+ * cpuset_change_task_nodemask - change task's mems_allowed and mempolicy
+ * @tsk: the task to change
+ * @newmems: new nodes that the task will be set
+ *
+ * In order to avoid seeing no nodes if the old and new nodes are disjoint,
+ * we structure updates as setting all new allowed nodes, then clearing newly
+ * disallowed ones.
+ *
+ * Called with task's alloc_lock held
+ */
+static void cpuset_change_task_nodemask(struct task_struct *tsk,
+                                        nodemask_t *newmems)
+{
+        nodes_or(tsk->mems_allowed, tsk->mems_allowed, *newmems);
+        mpol_rebind_task(tsk, &tsk->mems_allowed);
+        mpol_rebind_task(tsk, newmems);
+        tsk->mems_allowed = *newmems;
+}
+
+/*
+ * Update task's mems_allowed and rebind its mempolicy and vmas' mempolicy
+ * of it to cpuset's new mems_allowed, and migrate pages to new nodes if
+ * memory_migrate flag is set. Called with cgroup_mutex held.
  */
 static void cpuset_change_nodemask(struct task_struct *p,
                                    struct cgroup_scanner *scan)
@@ -1056,12 +974,19 @@ static void cpuset_change_nodemask(struct task_struct *p,
         struct cpuset *cs;
         int migrate;
         const nodemask_t *oldmem = scan->data;
+        nodemask_t newmems;
+
+        cs = cgroup_cs(scan->cg);
+        guarantee_online_mems(cs, &newmems);
+
+        task_lock(p);
+        cpuset_change_task_nodemask(p, &newmems);
+        task_unlock(p);
 
         mm = get_task_mm(p);
         if (!mm)
                 return;
 
-        cs = cgroup_cs(scan->cg);
         migrate = is_memory_migrate(cs);
 
         mpol_rebind_mm(mm, &cs->mems_allowed);
@@ -1114,10 +1039,10 @@ static void update_tasks_nodemask(struct cpuset *cs, const nodemask_t *oldmem,
 /*
  * Handle user request to change the 'mems' memory placement
  * of a cpuset.  Needs to validate the request, update the
- * cpusets mems_allowed and mems_generation, and for each
- * task in the cpuset, rebind any vma mempolicies and if
- * the cpuset is marked 'memory_migrate', migrate the tasks
- * pages to the new memory.
+ * cpusets mems_allowed, and for each task in the cpuset,
+ * update mems_allowed and rebind task's mempolicy and any vma
+ * mempolicies and if the cpuset is marked 'memory_migrate',
+ * migrate the tasks pages to the new memory.
  *
  * Call with cgroup_mutex held.  May take callback_mutex during call.
  * Will take tasklist_lock, scan tasklist for tasks in cpuset cs,
@@ -1170,7 +1095,6 @@ static int update_nodemask(struct cpuset *cs, struct cpuset *trialcs,
 
         mutex_lock(&callback_mutex);
         cs->mems_allowed = trialcs->mems_allowed;
-        cs->mems_generation = cpuset_mems_generation++;
         mutex_unlock(&callback_mutex);
 
         update_tasks_nodemask(cs, &oldmem, &heap);
@@ -1434,15 +1358,18 @@ static void cpuset_attach(struct cgroup_subsys *ss,
 
         if (cs == &top_cpuset) {
                 cpumask_copy(cpus_attach, cpu_possible_mask);
+                to = node_possible_map;
         } else {
-                mutex_lock(&callback_mutex);
                 guarantee_online_cpus(cs, cpus_attach);
-                mutex_unlock(&callback_mutex);
+                guarantee_online_mems(cs, &to);
         }
         err = set_cpus_allowed_ptr(tsk, cpus_attach);
         if (err)
                 return;
 
+        task_lock(tsk);
+        cpuset_change_task_nodemask(tsk, &to);
+        task_unlock(tsk);
         cpuset_update_task_spread_flag(cs, tsk);
 
         from = oldcs->mems_allowed;
@@ -1848,8 +1775,6 @@ static struct cgroup_subsys_state *cpuset_create(
         struct cpuset *parent;
 
         if (!cont->parent) {
-                /* This is early initialization for the top cgroup */
-                top_cpuset.mems_generation = cpuset_mems_generation++;
                 return &top_cpuset.css;
         }
         parent = cgroup_cs(cont->parent);
@@ -1861,7 +1786,6 @@ static struct cgroup_subsys_state *cpuset_create(
                 return ERR_PTR(-ENOMEM);
         }
 
-        cpuset_update_task_memory_state();
         cs->flags = 0;
         if (is_spread_page(parent))
                 set_bit(CS_SPREAD_PAGE, &cs->flags);
@@ -1870,7 +1794,6 @@ static struct cgroup_subsys_state *cpuset_create(
         set_bit(CS_SCHED_LOAD_BALANCE, &cs->flags);
         cpumask_clear(cs->cpus_allowed);
         nodes_clear(cs->mems_allowed);
-        cs->mems_generation = cpuset_mems_generation++;
         fmeter_init(&cs->fmeter);
         cs->relax_domain_level = -1;
 
@@ -1889,8 +1812,6 @@ static void cpuset_destroy(struct cgroup_subsys *ss, struct cgroup *cont)
 {
         struct cpuset *cs = cgroup_cs(cont);
 
-        cpuset_update_task_memory_state();
-
         if (is_sched_load_balance(cs))
                 update_flag(CS_SCHED_LOAD_BALANCE, cs, 0);
 
@@ -1911,21 +1832,6 @@ struct cgroup_subsys cpuset_subsys = {
         .early_init = 1,
 };
 
-/*
- * cpuset_init_early - just enough so that the calls to
- * cpuset_update_task_memory_state() in early init code
- * are harmless.
- */
-
-int __init cpuset_init_early(void)
-{
-        alloc_cpumask_var(&top_cpuset.cpus_allowed, GFP_NOWAIT);
-
-        top_cpuset.mems_generation = cpuset_mems_generation++;
-        return 0;
-}
-
-
 /**
  * cpuset_init - initialize cpusets at system boot
  *
@@ -1936,11 +1842,13 @@ int __init cpuset_init(void)
 {
         int err = 0;
 
+        if (!alloc_cpumask_var(&top_cpuset.cpus_allowed, GFP_KERNEL))
+                BUG();
+
         cpumask_setall(top_cpuset.cpus_allowed);
         nodes_setall(top_cpuset.mems_allowed);
 
         fmeter_init(&top_cpuset.fmeter);
-        top_cpuset.mems_generation = cpuset_mems_generation++;
         set_bit(CS_SCHED_LOAD_BALANCE, &top_cpuset.flags);
         top_cpuset.relax_domain_level = -1;
 
diff --git a/kernel/kthread.c b/kernel/kthread.c
index 41c88fe40500..7fa441333529 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -9,6 +9,7 @@
 #include <linux/kthread.h>
 #include <linux/completion.h>
 #include <linux/err.h>
+#include <linux/cpuset.h>
 #include <linux/unistd.h>
 #include <linux/file.h>
 #include <linux/module.h>
@@ -236,6 +237,7 @@ int kthreadd(void *unused)
         ignore_signals(tsk);
         set_user_nice(tsk, KTHREAD_NICE_LEVEL);
         set_cpus_allowed_ptr(tsk, cpu_all_mask);
+        set_mems_allowed(node_possible_map);
 
         current->flags |= PF_NOFREEZE | PF_FREEZER_NOSIG;
 
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 3eb4a6fdc043..46bdf9ddf2ba 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -182,13 +182,54 @@ static int mpol_new_bind(struct mempolicy *pol, const nodemask_t *nodes)
         return 0;
 }
 
-/* Create a new policy */
+/*
+ * mpol_set_nodemask is called after mpol_new() to set up the nodemask, if
+ * any, for the new policy.  mpol_new() has already validated the nodes
+ * parameter with respect to the policy mode and flags.  But, we need to
+ * handle an empty nodemask with MPOL_PREFERRED here.
+ *
+ * Must be called holding task's alloc_lock to protect task's mems_allowed
+ * and mempolicy.  May also be called holding the mmap_semaphore for write.
+ */
+static int mpol_set_nodemask(struct mempolicy *pol, const nodemask_t *nodes)
+{
+        nodemask_t cpuset_context_nmask;
+        int ret;
+
+        /* if mode is MPOL_DEFAULT, pol is NULL. This is right. */
+        if (pol == NULL)
+                return 0;
+
+        VM_BUG_ON(!nodes);
+        if (pol->mode == MPOL_PREFERRED && nodes_empty(*nodes))
+                nodes = NULL;   /* explicit local allocation */
+        else {
+                if (pol->flags & MPOL_F_RELATIVE_NODES)
+                        mpol_relative_nodemask(&cpuset_context_nmask, nodes,
+                                               &cpuset_current_mems_allowed);
+                else
+                        nodes_and(cpuset_context_nmask, *nodes,
+                                  cpuset_current_mems_allowed);
+                if (mpol_store_user_nodemask(pol))
+                        pol->w.user_nodemask = *nodes;
+                else
+                        pol->w.cpuset_mems_allowed =
+                                                cpuset_current_mems_allowed;
+        }
+
+        ret = mpol_ops[pol->mode].create(pol,
+                                nodes ? &cpuset_context_nmask : NULL);
+        return ret;
+}
+
+/*
+ * This function just creates a new policy, does some check and simple
+ * initialization. You must invoke mpol_set_nodemask() to set nodes.
+ */
 static struct mempolicy *mpol_new(unsigned short mode, unsigned short flags,
                                   nodemask_t *nodes)
 {
         struct mempolicy *policy;
-        nodemask_t cpuset_context_nmask;
-        int ret;
 
         pr_debug("setting mode %d flags %d nodes[0] %lx\n",
                  mode, flags, nodes ? nodes_addr(*nodes)[0] : -1);
@@ -210,7 +251,6 @@ static struct mempolicy *mpol_new(unsigned short mode, unsigned short flags,
                         if (((flags & MPOL_F_STATIC_NODES) ||
                              (flags & MPOL_F_RELATIVE_NODES)))
                                 return ERR_PTR(-EINVAL);
-                        nodes = NULL;   /* flag local alloc */
                 }
         } else if (nodes_empty(*nodes))
                 return ERR_PTR(-EINVAL);
@@ -221,30 +261,6 @@ static struct mempolicy *mpol_new(unsigned short mode, unsigned short flags,
         policy->mode = mode;
         policy->flags = flags;
 
-        if (nodes) {
-                /*
-                 * cpuset related setup doesn't apply to local allocation
-                 */
-                cpuset_update_task_memory_state();
-                if (flags & MPOL_F_RELATIVE_NODES)
-                        mpol_relative_nodemask(&cpuset_context_nmask, nodes,
-                                               &cpuset_current_mems_allowed);
-                else
-                        nodes_and(cpuset_context_nmask, *nodes,
-                                  cpuset_current_mems_allowed);
-                if (mpol_store_user_nodemask(policy))
-                        policy->w.user_nodemask = *nodes;
-                else
-                        policy->w.cpuset_mems_allowed =
-                                                cpuset_mems_allowed(current);
-        }
-
-        ret = mpol_ops[mode].create(policy,
-                                nodes ? &cpuset_context_nmask : NULL);
-        if (ret < 0) {
-                kmem_cache_free(policy_cache, policy);
-                return ERR_PTR(ret);
-        }
         return policy;
 }
 
@@ -324,6 +340,8 @@ static void mpol_rebind_policy(struct mempolicy *pol,
 /*
  * Wrapper for mpol_rebind_policy() that just requires task
  * pointer, and updates task mempolicy.
+ *
+ * Called with task's alloc_lock held.
  */
 
 void mpol_rebind_task(struct task_struct *tsk, const nodemask_t *new)
@@ -600,8 +618,9 @@ static void mpol_set_task_struct_flag(void)
 static long do_set_mempolicy(unsigned short mode, unsigned short flags,
                              nodemask_t *nodes)
 {
-        struct mempolicy *new;
+        struct mempolicy *new, *old;
         struct mm_struct *mm = current->mm;
+        int ret;
 
         new = mpol_new(mode, flags, nodes);
         if (IS_ERR(new))
@@ -615,20 +634,33 @@ static long do_set_mempolicy(unsigned short mode, unsigned short flags,
          */
         if (mm)
                 down_write(&mm->mmap_sem);
-        mpol_put(current->mempolicy);
+        task_lock(current);
+        ret = mpol_set_nodemask(new, nodes);
+        if (ret) {
+                task_unlock(current);
+                if (mm)
+                        up_write(&mm->mmap_sem);
+                mpol_put(new);
+                return ret;
+        }
+        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);
+        task_unlock(current);
         if (mm)
                 up_write(&mm->mmap_sem);
 
+        mpol_put(old);
         return 0;
 }
 
 /*
  * Return nodemask for policy for get_mempolicy() query
+ *
+ * Called with task's alloc_lock held
  */
 static void get_policy_nodemask(struct mempolicy *p, nodemask_t *nodes)
 {
@@ -674,7 +706,6 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask,
         struct vm_area_struct *vma = NULL;
         struct mempolicy *pol = current->mempolicy;
 
-        cpuset_update_task_memory_state();
         if (flags &
                 ~(unsigned long)(MPOL_F_NODE|MPOL_F_ADDR|MPOL_F_MEMS_ALLOWED))
                 return -EINVAL;
@@ -683,7 +714,9 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask,
                 if (flags & (MPOL_F_NODE|MPOL_F_ADDR))
                         return -EINVAL;
                 *policy = 0;    /* just so it's initialized */
+                task_lock(current);
                 *nmask  = cpuset_current_mems_allowed;
+                task_unlock(current);
                 return 0;
         }
 
@@ -738,8 +771,11 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask,
         }
 
         err = 0;
-        if (nmask)
+        if (nmask) {
+                task_lock(current);
                 get_policy_nodemask(pol, nmask);
+                task_unlock(current);
+        }
 
  out:
         mpol_cond_put(pol);
@@ -979,6 +1015,14 @@ static long do_mbind(unsigned long start, unsigned long len,
                         return err;
         }
         down_write(&mm->mmap_sem);
+        task_lock(current);
+        err = mpol_set_nodemask(new, nmask);
+        task_unlock(current);
+        if (err) {
+                up_write(&mm->mmap_sem);
+                mpol_put(new);
+                return err;
+        }
         vma = check_range(mm, start, end, nmask,
                           flags | MPOL_MF_INVERT, &pagelist);
 
@@ -1545,8 +1589,6 @@ alloc_page_vma(gfp_t gfp, struct vm_area_struct *vma, unsigned long addr)
         struct mempolicy *pol = get_vma_policy(current, vma, addr);
         struct zonelist *zl;
 
-        cpuset_update_task_memory_state();
-
         if (unlikely(pol->mode == MPOL_INTERLEAVE)) {
                 unsigned nid;
 
@@ -1593,8 +1635,6 @@ struct page *alloc_pages_current(gfp_t gfp, unsigned order)
 {
         struct mempolicy *pol = current->mempolicy;
 
-        if ((gfp & __GFP_WAIT) && !in_interrupt())
-                cpuset_update_task_memory_state();
         if (!pol || in_interrupt() || (gfp & __GFP_THISNODE))
                 pol = &default_policy;
 
@@ -1854,6 +1894,8 @@ restart:
  */
 void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol)
 {
+        int ret;
+
         sp->root = RB_ROOT;             /* empty tree == default mempolicy */
         spin_lock_init(&sp->lock);
 
@@ -1863,9 +1905,19 @@ void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol)
 
                 /* contextualize the tmpfs mount point mempolicy */
                 new = mpol_new(mpol->mode, mpol->flags, &mpol->w.user_nodemask);
-                mpol_put(mpol); /* drop our ref on sb mpol */
-                if (IS_ERR(new))
+                if (IS_ERR(new)) {
+                        mpol_put(mpol); /* drop our ref on sb mpol */
                         return;         /* no valid nodemask intersection */
+                }
+
+                task_lock(current);
+                ret = mpol_set_nodemask(new, &mpol->w.user_nodemask);
+                task_unlock(current);
+                mpol_put(mpol); /* drop our ref on sb mpol */
+                if (ret) {
+                        mpol_put(new);
+                        return;
+                }
 
                 /* Create pseudo-vma that contains just the policy */
                 memset(&pvma, 0, sizeof(struct vm_area_struct));
@@ -2086,8 +2138,19 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context)
         new = mpol_new(mode, mode_flags, &nodes);
         if (IS_ERR(new))
                 err = 1;
-        else if (no_context)
-                new->w.user_nodemask = nodes;   /* save for contextualization */
+        else {
+                int ret;
+
+                task_lock(current);
+                ret = mpol_set_nodemask(new, &nodes);
+                task_unlock(current);
+                if (ret)
+                        err = 1;
+                else if (no_context) {
+                        /* save for contextualization */
+                        new->w.user_nodemask = nodes;
+                }
+        }
 
 out:
         /* Restore string for error message */
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 17d5f539a9aa..7cc3179e3591 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1569,10 +1569,7 @@ nofail_alloc:
 
         /* We now go into synchronous reclaim */
         cpuset_memory_pressure_bump();
-        /*
-         * The task's cpuset might have expanded its set of allowable nodes
-         */
-        cpuset_update_task_memory_state();
+
         p->flags |= PF_MEMALLOC;
 
         lockdep_set_current_reclaim_state(gfp_mask);