workqueue: fix race condition in schedule_on_each_cpu()

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

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 1232814..67e526b 100644 (file)
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -692,31 +692,29 @@ int schedule_on_each_cpu(work_func_t func)
        if (!works)
                return -ENOMEM;
 
+       get_online_cpus();
+
        /*
-        * when running in keventd don't schedule a work item on itself.
-        * Can just call directly because the work queue is already bound.
-        * This also is faster.
-        * Make this a generic parameter for other workqueues?
+        * When running in keventd don't schedule a work item on
+        * itself.  Can just call directly because the work queue is
+        * already bound.  This also is faster.
         */
-       if (current_is_keventd()) {
+       if (current_is_keventd())
                orig = raw_smp_processor_id();
-               INIT_WORK(per_cpu_ptr(works, orig), func);
-               func(per_cpu_ptr(works, orig));
-       }
 
-       get_online_cpus();
        for_each_online_cpu(cpu) {
                struct work_struct *work = per_cpu_ptr(works, cpu);
 
-               if (cpu == orig)
-                       continue;
                INIT_WORK(work, func);
-               schedule_work_on(cpu, work);
-       }
-       for_each_online_cpu(cpu) {
                if (cpu != orig)
-                       flush_work(per_cpu_ptr(works, cpu));
+                       schedule_work_on(cpu, work);
        }
+       if (orig >= 0)
+               func(per_cpu_ptr(works, orig));
+
+       for_each_online_cpu(cpu)
+               flush_work(per_cpu_ptr(works, cpu));
+
        put_online_cpus();
        free_percpu(works);
        return 0;