From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Andrew Morton <akpm@osdl.org>, linux-kernel@vger.kernel.org
Cc: Ingo Molnar <mingo@elte.hu>, Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: [PATCH 6/7] schedule_on_each_cpu_wq()
Date: Sun, 28 Jan 2007 12:51:24 +0100 [thread overview]
Message-ID: <20070128120510.851511000@programming.kicks-ass.net> (raw)
In-Reply-To: 20070128115118.837777000@programming.kicks-ass.net
[-- Attachment #1: s_files-schedule_on_each_cpu_wq.patch --]
[-- Type: text/plain, Size: 3618 bytes --]
From: Ingo Molnar <mingo@elte.hu>
Provide a schedule_on_each_cpu_wq() function that uses a workqueue to do all
the work. This avoid the calling process to schedule.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
---
include/linux/workqueue.h | 1
kernel/workqueue.c | 66 ++++++++++++++++++++++++++++++++++++++--------
2 files changed, 56 insertions(+), 11 deletions(-)
Index: linux-2.6/include/linux/workqueue.h
===================================================================
--- linux-2.6.orig/include/linux/workqueue.h 2007-01-13 21:04:11.000000000 +0100
+++ linux-2.6/include/linux/workqueue.h 2007-01-27 21:12:16.000000000 +0100
@@ -179,6 +179,7 @@ extern int FASTCALL(schedule_delayed_wor
extern int schedule_delayed_work_on(int cpu, struct delayed_work *work, unsigned long delay);
extern int schedule_on_each_cpu(work_func_t func);
+extern int schedule_on_each_cpu_wq(struct workqueue_struct *wq, work_func_t func);
extern void flush_scheduled_work(void);
extern int current_is_keventd(void);
extern int keventd_up(void);
Index: linux-2.6/kernel/workqueue.c
===================================================================
--- linux-2.6.orig/kernel/workqueue.c 2007-01-13 21:04:12.000000000 +0100
+++ linux-2.6/kernel/workqueue.c 2007-01-27 21:12:16.000000000 +0100
@@ -296,6 +296,20 @@ int queue_delayed_work_on(int cpu, struc
}
EXPORT_SYMBOL_GPL(queue_delayed_work_on);
+static void leak_check(void *func)
+{
+ if (!in_atomic() && lockdep_depth(current) <= 0)
+ return;
+ printk(KERN_ERR "BUG: workqueue leaked lock or atomic: "
+ "%s/0x%08x/%d\n",
+ current->comm, preempt_count(),
+ current->pid);
+ printk(KERN_ERR " last function: ");
+ print_symbol("%s\n", (unsigned long)func);
+ debug_show_held_locks(current);
+ dump_stack();
+}
+
static void run_workqueue(struct cpu_workqueue_struct *cwq)
{
unsigned long flags;
@@ -323,18 +337,10 @@ static void run_workqueue(struct cpu_wor
BUG_ON(get_wq_data(work) != cwq);
if (!test_bit(WORK_STRUCT_NOAUTOREL, work_data_bits(work)))
work_release(work);
- f(work);
- if (unlikely(in_atomic() || lockdep_depth(current) > 0)) {
- printk(KERN_ERR "BUG: workqueue leaked lock or atomic: "
- "%s/0x%08x/%d\n",
- current->comm, preempt_count(),
- current->pid);
- printk(KERN_ERR " last function: ");
- print_symbol("%s\n", (unsigned long)f);
- debug_show_held_locks(current);
- dump_stack();
- }
+ leak_check(NULL);
+ f(work);
+ leak_check(f);
spin_lock_irqsave(&cwq->lock, flags);
cwq->remove_sequence++;
@@ -649,6 +655,44 @@ int schedule_on_each_cpu(work_func_t fun
return 0;
}
+/**
+ * schedule_on_each_cpu_wq - call a function on each online CPU on a per-CPU wq
+ * @func: the function to call
+ *
+ * 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_wq(struct workqueue_struct *wq, work_func_t func)
+{
+ int cpu;
+ struct work_struct *works;
+
+ if (is_single_threaded(wq)) {
+ WARN_ON(1);
+ return -EINVAL;
+ }
+ works = alloc_percpu(struct work_struct);
+ if (!works)
+ return -ENOMEM;
+
+ for_each_online_cpu(cpu) {
+ struct work_struct *work = per_cpu_ptr(works, cpu);
+
+ INIT_WORK(work, func);
+ set_bit(WORK_STRUCT_PENDING, work_data_bits(work));
+ __queue_work(per_cpu_ptr(wq->cpu_wq, cpu), work);
+ }
+ flush_workqueue(wq);
+ free_percpu(works);
+
+ return 0;
+}
+
+
void flush_scheduled_work(void)
{
flush_workqueue(keventd_wq);
--
next prev parent reply other threads:[~2007-01-28 12:11 UTC|newest]
Thread overview: 54+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-01-28 11:51 [PATCH 0/7] breaking the global file_list_lock Peter Zijlstra
2007-01-28 11:51 ` [PATCH 1/7] lockdep: lock_set_subclass - reset a held locks subclass Peter Zijlstra
2007-01-28 11:51 ` [PATCH 3/7] barrier: a scalable synchonisation barrier Peter Zijlstra
2007-01-28 14:39 ` Christoph Hellwig
2007-01-28 15:24 ` Ingo Molnar
2007-01-28 15:34 ` Christoph Hellwig
2007-01-31 19:12 ` Paul E. McKenney
2007-01-31 21:13 ` Oleg Nesterov
2007-01-31 21:30 ` Oleg Nesterov
2007-01-31 21:48 ` Peter Zijlstra
2007-01-31 23:32 ` Paul E. McKenney
2007-02-01 0:03 ` Peter Zijlstra
2007-02-01 0:48 ` Paul E. McKenney
2007-02-01 16:00 ` Oleg Nesterov
2007-02-01 21:38 ` Paul E. McKenney
2007-02-02 11:56 ` Oleg Nesterov
2007-02-02 12:01 ` Peter Zijlstra
2007-02-02 17:13 ` Paul E. McKenney
2007-02-03 16:38 ` Oleg Nesterov
2007-02-04 0:23 ` Paul E. McKenney
2007-02-04 3:24 ` Alan Stern
2007-02-04 5:46 ` Paul E. McKenney
2007-01-28 11:51 ` [PATCH 4/7] fs: break the file_list_lock for sb->s_files Peter Zijlstra
2007-01-28 14:43 ` Christoph Hellwig
2007-01-28 15:21 ` Ingo Molnar
2007-01-28 15:30 ` Christoph Hellwig
2007-01-28 15:32 ` Peter Zijlstra
2007-01-28 15:36 ` Christoph Hellwig
2007-01-28 15:44 ` Ingo Molnar
2007-01-28 16:25 ` Bill Huey
2007-01-28 11:51 ` [PATCH 5/7] fs: restore previous sb->s_files iteration semantics Peter Zijlstra
2007-01-28 11:51 ` Peter Zijlstra [this message]
2007-01-28 11:51 ` [PATCH 7/7] fs: fixup filevec_add_drain_all Peter Zijlstra
2007-01-28 12:16 ` [PATCH 8/7] fs: free_write_pipe() fix Peter Zijlstra
2007-01-28 14:43 ` [PATCH 0/7] breaking the global file_list_lock Christoph Hellwig
2007-01-28 15:11 ` Christoph Hellwig
2007-01-28 15:29 ` Peter Zijlstra
2007-01-28 15:33 ` Christoph Hellwig
2007-01-29 13:32 ` Stephen Smalley
2007-01-29 18:02 ` Christoph Hellwig
2007-01-28 15:24 ` Ingo Molnar
2007-01-28 16:52 ` Martin J. Bligh
2007-01-28 17:04 ` lockmeter Christoph Hellwig
2007-01-28 17:38 ` lockmeter Martin J. Bligh
2007-01-28 18:01 ` lockmeter Bill Huey
2007-01-28 19:26 ` lockmeter Ingo Molnar
2007-01-28 21:17 ` lockmeter Ingo Molnar
2007-01-29 5:27 ` lockmeter Bill Huey
2007-01-29 10:26 ` lockmeter Bill Huey
2007-01-29 1:08 ` lockmeter Arjan van de Ven
2007-01-29 1:12 ` lockmeter Martin J. Bligh
2007-01-28 18:41 ` [PATCH 0/7] breaking the global file_list_lock Ingo Molnar
2007-01-28 20:38 ` Christoph Hellwig
2007-01-28 21:05 ` Ingo Molnar
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