netns xfrm: /proc/net/xfrm_stat in netns

[safe/jmp/linux-2.6] / kernel / workqueue.c

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index ec7e4f6..d4dc69d 100644 (file)
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -9,7 +9,7 @@
  * Derived from the taskqueue/keventd code by:
  *
  *   David Woodhouse <dwmw2@infradead.org>
- *   Andrew Morton <andrewm@uow.edu.au>
+ *   Andrew Morton
  *   Kai Petzke <wpp@marie.physik.tu-berlin.de>
  *   Theodore Ts'o <tytso@mit.edu>
  *
@@ -62,6 +62,7 @@ struct workqueue_struct {
        const char *name;
        int singlethread;
        int freezeable;         /* Freeze threads during suspend */
+       int rt;
 #ifdef CONFIG_LOCKDEP
        struct lockdep_map lockdep_map;
 #endif
@@ -290,11 +291,11 @@ static void run_workqueue(struct cpu_workqueue_struct *cwq)
 
                BUG_ON(get_wq_data(work) != cwq);
                work_clear_pending(work);
-               lock_acquire(&cwq->wq->lockdep_map, 0, 0, 0, 2, _THIS_IP_);
-               lock_acquire(&lockdep_map, 0, 0, 0, 2, _THIS_IP_);
+               lock_map_acquire(&cwq->wq->lockdep_map);
+               lock_map_acquire(&lockdep_map);
                f(work);
-               lock_release(&lockdep_map, 1, _THIS_IP_);
-               lock_release(&cwq->wq->lockdep_map, 1, _THIS_IP_);
+               lock_map_release(&lockdep_map);
+               lock_map_release(&cwq->wq->lockdep_map);
 
                if (unlikely(in_atomic() || lockdep_depth(current) > 0)) {
                        printk(KERN_ERR "BUG: workqueue leaked lock or atomic: "
@@ -413,8 +414,8 @@ void flush_workqueue(struct workqueue_struct *wq)
        int cpu;
 
        might_sleep();
-       lock_acquire(&wq->lockdep_map, 0, 0, 0, 2, _THIS_IP_);
-       lock_release(&wq->lockdep_map, 1, _THIS_IP_);
+       lock_map_acquire(&wq->lockdep_map);
+       lock_map_release(&wq->lockdep_map);
        for_each_cpu_mask_nr(cpu, *cpu_map)
                flush_cpu_workqueue(per_cpu_ptr(wq->cpu_wq, cpu));
 }
@@ -441,8 +442,8 @@ int flush_work(struct work_struct *work)
        if (!cwq)
                return 0;
 
-       lock_acquire(&cwq->wq->lockdep_map, 0, 0, 0, 2, _THIS_IP_);
-       lock_release(&cwq->wq->lockdep_map, 1, _THIS_IP_);
+       lock_map_acquire(&cwq->wq->lockdep_map);
+       lock_map_release(&cwq->wq->lockdep_map);
 
        prev = NULL;
        spin_lock_irq(&cwq->lock);
@@ -536,8 +537,8 @@ static void wait_on_work(struct work_struct *work)
 
        might_sleep();
 
-       lock_acquire(&work->lockdep_map, 0, 0, 0, 2, _THIS_IP_);
-       lock_release(&work->lockdep_map, 1, _THIS_IP_);
+       lock_map_acquire(&work->lockdep_map);
+       lock_map_release(&work->lockdep_map);
 
        cwq = get_wq_data(work);
        if (!cwq)
@@ -766,6 +767,7 @@ init_cpu_workqueue(struct workqueue_struct *wq, int cpu)
 
 static int create_workqueue_thread(struct cpu_workqueue_struct *cwq, int cpu)
 {
+       struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 };
        struct workqueue_struct *wq = cwq->wq;
        const char *fmt = is_single_threaded(wq) ? "%s" : "%s/%d";
        struct task_struct *p;
@@ -781,7 +783,8 @@ static int create_workqueue_thread(struct cpu_workqueue_struct *cwq, int cpu)
         */
        if (IS_ERR(p))
                return PTR_ERR(p);
-
+       if (cwq->wq->rt)
+               sched_setscheduler_nocheck(p, SCHED_FIFO, &param);
        cwq->thread = p;
 
        return 0;
@@ -801,6 +804,7 @@ static void start_workqueue_thread(struct cpu_workqueue_struct *cwq, int cpu)
 struct workqueue_struct *__create_workqueue_key(const char *name,
                                                int singlethread,
                                                int freezeable,
+                                               int rt,
                                                struct lock_class_key *key,
                                                const char *lock_name)
 {
@@ -822,6 +826,7 @@ struct workqueue_struct *__create_workqueue_key(const char *name,
        lockdep_init_map(&wq->lockdep_map, lock_name, key, 0);
        wq->singlethread = singlethread;
        wq->freezeable = freezeable;
+       wq->rt = rt;
        INIT_LIST_HEAD(&wq->list);
 
        if (singlethread) {
@@ -830,10 +835,21 @@ struct workqueue_struct *__create_workqueue_key(const char *name,
                start_workqueue_thread(cwq, -1);
        } else {
                cpu_maps_update_begin();
+               /*
+                * We must place this wq on list even if the code below fails.
+                * cpu_down(cpu) can remove cpu from cpu_populated_map before
+                * destroy_workqueue() takes the lock, in that case we leak
+                * cwq[cpu]->thread.
+                */
                spin_lock(&workqueue_lock);
                list_add(&wq->list, &workqueues);
                spin_unlock(&workqueue_lock);
-
+               /*
+                * We must initialize cwqs for each possible cpu even if we
+                * are going to call destroy_workqueue() finally. Otherwise
+                * cpu_up() can hit the uninitialized cwq once we drop the
+                * lock.
+                */
                for_each_possible_cpu(cpu) {
                        cwq = init_cpu_workqueue(wq, cpu);
                        if (err || !cpu_online(cpu))
@@ -861,8 +877,8 @@ static void cleanup_workqueue_thread(struct cpu_workqueue_struct *cwq)
        if (cwq->thread == NULL)
                return;
 
-       lock_acquire(&cwq->wq->lockdep_map, 0, 0, 0, 2, _THIS_IP_);
-       lock_release(&cwq->wq->lockdep_map, 1, _THIS_IP_);
+       lock_map_acquire(&cwq->wq->lockdep_map);
+       lock_map_release(&cwq->wq->lockdep_map);
 
        flush_cpu_workqueue(cwq);
        /*
@@ -954,6 +970,51 @@ undo:
        return ret;
 }
 
+#ifdef CONFIG_SMP
+struct work_for_cpu {
+       struct work_struct work;
+       long (*fn)(void *);
+       void *arg;
+       long ret;
+};
+
+static void do_work_for_cpu(struct work_struct *w)
+{
+       struct work_for_cpu *wfc = container_of(w, struct work_for_cpu, work);
+
+       wfc->ret = wfc->fn(wfc->arg);
+}
+
+/**
+ * work_on_cpu - run a function in user context on a particular cpu
+ * @cpu: the cpu to run on
+ * @fn: the function to run
+ * @arg: the function arg
+ *
+ * This will return -EINVAL in the cpu is not online, or the return value
+ * of @fn otherwise.
+ */
+long work_on_cpu(unsigned int cpu, long (*fn)(void *), void *arg)
+{
+       struct work_for_cpu wfc;
+
+       INIT_WORK(&wfc.work, do_work_for_cpu);
+       wfc.fn = fn;
+       wfc.arg = arg;
+       get_online_cpus();
+       if (unlikely(!cpu_online(cpu)))
+               wfc.ret = -EINVAL;
+       else {
+               schedule_work_on(cpu, &wfc.work);
+               flush_work(&wfc.work);
+       }
+       put_online_cpus();
+
+       return wfc.ret;
+}
+EXPORT_SYMBOL_GPL(work_on_cpu);
+#endif /* CONFIG_SMP */
+
 void __init init_workqueues(void)
 {
        cpu_populated_map = cpu_online_map;