* Andrew Morton <andrewm@uow.edu.au>
* Kai Petzke <wpp@marie.physik.tu-berlin.de>
* Theodore Ts'o <tytso@mit.edu>
+ *
+ * Made to use alloc_percpu by Christoph Lameter <clameter@sgi.com>.
*/
#include <linux/module.h>
#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 cpu 0's).
+ * The per-CPU workqueue (if single thread, we always use the first
+ * possible cpu).
*
* The sequence counters are for flush_scheduled_work(). It wants to wait
* until until all currently-scheduled works are completed, but it doesn't
* per-CPU workqueues:
*/
struct workqueue_struct {
- struct cpu_workqueue_struct cpu_wq[NR_CPUS];
+ struct cpu_workqueue_struct *cpu_wq;
const char *name;
struct list_head list; /* Empty if single thread */
};
static DEFINE_SPINLOCK(workqueue_lock);
static LIST_HEAD(workqueues);
+static int singlethread_cpu;
+
/* If it's single threaded, it isn't in the list of workqueues. */
static inline int is_single_threaded(struct workqueue_struct *wq)
{
if (!test_and_set_bit(0, &work->pending)) {
if (unlikely(is_single_threaded(wq)))
- cpu = 0;
+ cpu = singlethread_cpu;
BUG_ON(!list_empty(&work->entry));
- __queue_work(wq->cpu_wq + cpu, work);
+ __queue_work(per_cpu_ptr(wq->cpu_wq, cpu), work);
ret = 1;
}
put_cpu();
int cpu = smp_processor_id();
if (unlikely(is_single_threaded(wq)))
- cpu = 0;
+ cpu = singlethread_cpu;
- __queue_work(wq->cpu_wq + cpu, work);
+ __queue_work(per_cpu_ptr(wq->cpu_wq, cpu), work);
}
int fastcall queue_delayed_work(struct workqueue_struct *wq,
return ret;
}
-static inline void run_workqueue(struct cpu_workqueue_struct *cwq)
+static void run_workqueue(struct cpu_workqueue_struct *cwq)
{
unsigned long flags;
might_sleep();
if (is_single_threaded(wq)) {
- /* Always use cpu 0's area. */
- flush_cpu_workqueue(wq->cpu_wq + 0);
+ /* Always use first cpu's area. */
+ flush_cpu_workqueue(per_cpu_ptr(wq->cpu_wq, singlethread_cpu));
} else {
int cpu;
lock_cpu_hotplug();
for_each_online_cpu(cpu)
- flush_cpu_workqueue(wq->cpu_wq + cpu);
+ flush_cpu_workqueue(per_cpu_ptr(wq->cpu_wq, cpu));
unlock_cpu_hotplug();
}
}
static struct task_struct *create_workqueue_thread(struct workqueue_struct *wq,
int cpu)
{
- struct cpu_workqueue_struct *cwq = wq->cpu_wq + cpu;
+ struct cpu_workqueue_struct *cwq = per_cpu_ptr(wq->cpu_wq, cpu);
struct task_struct *p;
spin_lock_init(&cwq->lock);
struct workqueue_struct *wq;
struct task_struct *p;
- BUG_ON(strlen(name) > 10);
-
- wq = kmalloc(sizeof(*wq), GFP_KERNEL);
+ wq = kzalloc(sizeof(*wq), GFP_KERNEL);
if (!wq)
return NULL;
- memset(wq, 0, sizeof(*wq));
+
+ wq->cpu_wq = alloc_percpu(struct cpu_workqueue_struct);
+ if (!wq->cpu_wq) {
+ kfree(wq);
+ return NULL;
+ }
wq->name = name;
/* We don't need the distraction of CPUs appearing and vanishing. */
lock_cpu_hotplug();
if (singlethread) {
INIT_LIST_HEAD(&wq->list);
- p = create_workqueue_thread(wq, 0);
+ p = create_workqueue_thread(wq, singlethread_cpu);
if (!p)
destroy = 1;
else
unsigned long flags;
struct task_struct *p;
- cwq = wq->cpu_wq + cpu;
+ cwq = per_cpu_ptr(wq->cpu_wq, cpu);
spin_lock_irqsave(&cwq->lock, flags);
p = cwq->thread;
cwq->thread = NULL;
/* We don't need the distraction of CPUs appearing and vanishing. */
lock_cpu_hotplug();
if (is_single_threaded(wq))
- cleanup_workqueue_thread(wq, 0);
+ cleanup_workqueue_thread(wq, singlethread_cpu);
else {
for_each_online_cpu(cpu)
cleanup_workqueue_thread(wq, cpu);
spin_unlock(&workqueue_lock);
}
unlock_cpu_hotplug();
+ free_percpu(wq->cpu_wq);
kfree(wq);
}
return ret;
}
+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);
+
+ if (!work)
+ return -ENOMEM;
+ for_each_online_cpu(cpu) {
+ INIT_WORK(work + cpu, func, info);
+ __queue_work(per_cpu_ptr(keventd_wq->cpu_wq, cpu),
+ work + cpu);
+ }
+ flush_workqueue(keventd_wq);
+ kfree(work);
+ return 0;
+}
+
void flush_scheduled_work(void)
{
flush_workqueue(keventd_wq);
}
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;
BUG_ON(!keventd_wq);
- cwq = keventd_wq->cpu_wq + cpu;
+ cwq = per_cpu_ptr(keventd_wq->cpu_wq, cpu);
if (current == cwq->thread)
ret = 1;
/* Take the work from this (downed) CPU. */
static void take_over_work(struct workqueue_struct *wq, unsigned int cpu)
{
- struct cpu_workqueue_struct *cwq = wq->cpu_wq + cpu;
+ struct cpu_workqueue_struct *cwq = per_cpu_ptr(wq->cpu_wq, cpu);
LIST_HEAD(list);
struct work_struct *work;
printk("Taking work for %s\n", wq->name);
work = list_entry(list.next,struct work_struct,entry);
list_del(&work->entry);
- __queue_work(wq->cpu_wq + smp_processor_id(), work);
+ __queue_work(per_cpu_ptr(wq->cpu_wq, smp_processor_id()), work);
}
spin_unlock_irq(&cwq->lock);
}
/* We're holding the cpucontrol mutex here */
-static int __devinit workqueue_cpu_callback(struct notifier_block *nfb,
+static int workqueue_cpu_callback(struct notifier_block *nfb,
unsigned long action,
void *hcpu)
{
case CPU_UP_PREPARE:
/* Create a new workqueue thread for it. */
list_for_each_entry(wq, &workqueues, list) {
- if (create_workqueue_thread(wq, hotcpu) < 0) {
+ if (!create_workqueue_thread(wq, hotcpu)) {
printk("workqueue for %i failed\n", hotcpu);
return NOTIFY_BAD;
}
case CPU_ONLINE:
/* Kick off worker threads. */
list_for_each_entry(wq, &workqueues, list) {
- kthread_bind(wq->cpu_wq[hotcpu].thread, hotcpu);
- wake_up_process(wq->cpu_wq[hotcpu].thread);
+ struct cpu_workqueue_struct *cwq;
+
+ cwq = per_cpu_ptr(wq->cpu_wq, hotcpu);
+ kthread_bind(cwq->thread, hotcpu);
+ wake_up_process(cwq->thread);
}
break;
case CPU_UP_CANCELED:
list_for_each_entry(wq, &workqueues, list) {
/* Unbind so it can run. */
- kthread_bind(wq->cpu_wq[hotcpu].thread,
- smp_processor_id());
+ kthread_bind(per_cpu_ptr(wq->cpu_wq, hotcpu)->thread,
+ any_online_cpu(cpu_online_map));
cleanup_workqueue_thread(wq, hotcpu);
}
break;
void init_workqueues(void)
{
+ singlethread_cpu = first_cpu(cpu_possible_map);
hotcpu_notifier(workqueue_cpu_callback, 0);
keventd_wq = create_workqueue("events");
BUG_ON(!keventd_wq);