X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=kernel%2Fworkqueue.c;h=59f0b42bd89e0e819a1a67145f48a11f2898bbd2;hb=8f7c58814eb75bf97b8bc18d107b2e26f28b6585;hp=b052e2c4c71053720e87606e20924cfec5f3f27c;hpb=f1dccedc8148026d9071c6805f7cb77374a9e56f;p=powerpc.git

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index b052e2c4c7..59f0b42bd8 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -27,6 +27,7 @@
 #include <linux/cpu.h>
 #include <linux/notifier.h>
 #include <linux/kthread.h>
+#include <linux/hardirq.h>
 
 /*
  * The per-CPU workqueue (if single thread, we always use the first
@@ -427,22 +428,34 @@ int schedule_delayed_work_on(int cpu,
 	return ret;
 }
 
-int schedule_on_each_cpu(void (*func) (void *info), void *info)
+/**
+ * schedule_on_each_cpu - call a function on each online CPU from keventd
+ * @func: the function to call
+ * @info: a pointer to pass to func()
+ *
+ * Returns zero on success.
+ * Returns -ve errno on failure.
+ *
+ * Appears to be racy against CPU hotplug.
+ *
+ * schedule_on_each_cpu() is very slow.
+ */
+int schedule_on_each_cpu(void (*func)(void *info), void *info)
 {
 	int cpu;
-	struct work_struct *work;
-
-	work = kmalloc(NR_CPUS * sizeof(struct work_struct), GFP_KERNEL);
+	struct work_struct *works;
 
-	if (!work)
+	works = alloc_percpu(struct work_struct);
+	if (!works)
 		return -ENOMEM;
+
 	for_each_online_cpu(cpu) {
-		INIT_WORK(work + cpu, func, info);
+		INIT_WORK(per_cpu_ptr(works, cpu), func, info);
 		__queue_work(per_cpu_ptr(keventd_wq->cpu_wq, cpu),
-				work + cpu);
+				per_cpu_ptr(works, cpu));
 	}
 	flush_workqueue(keventd_wq);
-	kfree(work);
+	free_percpu(works);
 	return 0;
 }
 
@@ -476,6 +489,34 @@ void cancel_rearming_delayed_work(struct work_struct *work)
 }
 EXPORT_SYMBOL(cancel_rearming_delayed_work);
 
+/**
+ * execute_in_process_context - reliably execute the routine with user context
+ * @fn:		the function to execute
+ * @data:	data to pass to the function
+ * @ew:		guaranteed storage for the execute work structure (must
+ *		be available when the work executes)
+ *
+ * Executes the function immediately if process context is available,
+ * otherwise schedules the function for delayed execution.
+ *
+ * Returns:	0 - function was executed
+ *		1 - function was scheduled for execution
+ */
+int execute_in_process_context(void (*fn)(void *data), void *data,
+			       struct execute_work *ew)
+{
+	if (!in_interrupt()) {
+		fn(data);
+		return 0;
+	}
+
+	INIT_WORK(&ew->work, fn, data);
+	schedule_work(&ew->work);
+
+	return 1;
+}
+EXPORT_SYMBOL_GPL(execute_in_process_context);
+
 int keventd_up(void)
 {
 	return keventd_wq != NULL;
@@ -502,11 +543,11 @@ int current_is_keventd(void)
 static void take_over_work(struct workqueue_struct *wq, unsigned int cpu)
 {
 	struct cpu_workqueue_struct *cwq = per_cpu_ptr(wq->cpu_wq, cpu);
-	LIST_HEAD(list);
+	struct list_head list;
 	struct work_struct *work;
 
 	spin_lock_irq(&cwq->lock);
-	list_splice_init(&cwq->worklist, &list);
+	list_replace_init(&cwq->worklist, &list);
 
 	while (!list_empty(&list)) {
 		printk("Taking work for %s\n", wq->name);
@@ -549,6 +590,8 @@ static int __devinit workqueue_cpu_callback(struct notifier_block *nfb,
 
 	case CPU_UP_CANCELED:
 		list_for_each_entry(wq, &workqueues, list) {
+			if (!per_cpu_ptr(wq->cpu_wq, hotcpu)->thread)
+				continue;
 			/* Unbind so it can run. */
 			kthread_bind(per_cpu_ptr(wq->cpu_wq, hotcpu)->thread,
 				     any_online_cpu(cpu_online_map));