mmc: dw_mmc: fix unmap sg twice when finding data err

[firefly-linux-kernel-4.4.55.git] / kernel / cpuset.c

diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 02a8ea5c99632907b2ae887015c59bd4ad35da9d..11eaf14b52c2919b63131485d33dd2e7203aca58 100644 (file)
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -57,7 +57,6 @@
 #include <asm/uaccess.h>
 #include <linux/atomic.h>
 #include <linux/mutex.h>
-#include <linux/workqueue.h>
 #include <linux/cgroup.h>
 #include <linux/wait.h>
 
@@ -286,6 +285,8 @@ static struct cpuset top_cpuset = {
 static DEFINE_MUTEX(cpuset_mutex);
 static DEFINE_SPINLOCK(callback_lock);
 
+static struct workqueue_struct *cpuset_migrate_mm_wq;
+
 /*
  * CPU / memory hotplug is handled asynchronously.
  */
@@ -971,31 +972,51 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs,
 }
 
 /*
- * cpuset_migrate_mm
- *
- *    Migrate memory region from one set of nodes to another.
- *
- *    Temporarilly set tasks mems_allowed to target nodes of migration,
- *    so that the migration code can allocate pages on these nodes.
- *
- *    While the mm_struct we are migrating is typically from some
- *    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.
+ * Migrate memory region from one set of nodes to another.  This is
+ * performed asynchronously as it can be called from process migration path
+ * holding locks involved in process management.  All mm migrations are
+ * performed in the queued order and can be waited for by flushing
+ * cpuset_migrate_mm_wq.
  */
 
+struct cpuset_migrate_mm_work {
+       struct work_struct      work;
+       struct mm_struct        *mm;
+       nodemask_t              from;
+       nodemask_t              to;
+};
+
+static void cpuset_migrate_mm_workfn(struct work_struct *work)
+{
+       struct cpuset_migrate_mm_work *mwork =
+               container_of(work, struct cpuset_migrate_mm_work, work);
+
+       /* on a wq worker, no need to worry about %current's mems_allowed */
+       do_migrate_pages(mwork->mm, &mwork->from, &mwork->to, MPOL_MF_MOVE_ALL);
+       mmput(mwork->mm);
+       kfree(mwork);
+}
+
 static void cpuset_migrate_mm(struct mm_struct *mm, const nodemask_t *from,
                                                        const nodemask_t *to)
 {
-       struct task_struct *tsk = current;
-
-       tsk->mems_allowed = *to;
+       struct cpuset_migrate_mm_work *mwork;
 
-       do_migrate_pages(mm, from, to, MPOL_MF_MOVE_ALL);
+       mwork = kzalloc(sizeof(*mwork), GFP_KERNEL);
+       if (mwork) {
+               mwork->mm = mm;
+               mwork->from = *from;
+               mwork->to = *to;
+               INIT_WORK(&mwork->work, cpuset_migrate_mm_workfn);
+               queue_work(cpuset_migrate_mm_wq, &mwork->work);
+       } else {
+               mmput(mm);
+       }
+}
 
-       rcu_read_lock();
-       guarantee_online_mems(task_cs(tsk), &tsk->mems_allowed);
-       rcu_read_unlock();
+static void cpuset_post_attach(void)
+{
+       flush_workqueue(cpuset_migrate_mm_wq);
 }
 
 /*
@@ -1096,7 +1117,8 @@ static void update_tasks_nodemask(struct cpuset *cs)
                mpol_rebind_mm(mm, &cs->mems_allowed);
                if (migrate)
                        cpuset_migrate_mm(mm, &cs->old_mems_allowed, &newmems);
-               mmput(mm);
+               else
+                       mmput(mm);
        }
        css_task_iter_end(&it);
 
@@ -1541,11 +1563,11 @@ static void cpuset_attach(struct cgroup_taskset *tset)
                         * @old_mems_allowed is the right nodesets that we
                         * migrate mm from.
                         */
-                       if (is_memory_migrate(cs)) {
+                       if (is_memory_migrate(cs))
                                cpuset_migrate_mm(mm, &oldcs->old_mems_allowed,
                                                  &cpuset_attach_nodemask_to);
-                       }
-                       mmput(mm);
+                       else
+                               mmput(mm);
                }
        }
 
@@ -1710,6 +1732,7 @@ out_unlock:
        mutex_unlock(&cpuset_mutex);
        kernfs_unbreak_active_protection(of->kn);
        css_put(&cs->css);
+       flush_workqueue(cpuset_migrate_mm_wq);
        return retval ?: nbytes;
 }
 
@@ -2059,6 +2082,7 @@ struct cgroup_subsys cpuset_cgrp_subsys = {
        .can_attach     = cpuset_can_attach,
        .cancel_attach  = cpuset_cancel_attach,
        .attach         = cpuset_attach,
+       .post_attach    = cpuset_post_attach,
        .bind           = cpuset_bind,
        .legacy_cftypes = files,
        .early_init     = 1,
@@ -2355,6 +2379,9 @@ void __init cpuset_init_smp(void)
        top_cpuset.effective_mems = node_states[N_MEMORY];
 
        register_hotmemory_notifier(&cpuset_track_online_nodes_nb);
+
+       cpuset_migrate_mm_wq = alloc_ordered_workqueue("cpuset_migrate_mm", 0);
+       BUG_ON(!cpuset_migrate_mm_wq);
 }
 
 /**