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authorLinus Torvalds <torvalds@linux-foundation.org>2010-08-07 12:42:58 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-08-07 12:42:58 -0700
commit3b7433b8a8a83c87972065b1852b7dcae691e464 (patch)
tree93fa2c003f8baef5ab0733b53bac77961ed5240c /kernel
parent4a386c3e177ca2fbc70c9283d0b46537844763a0 (diff)
parent6ee0578b4daaea01c96b172c6aacca43fd9807a6 (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (55 commits) workqueue: mark init_workqueues() as early_initcall() workqueue: explain for_each_*cwq_cpu() iterators fscache: fix build on !CONFIG_SYSCTL slow-work: kill it gfs2: use workqueue instead of slow-work drm: use workqueue instead of slow-work cifs: use workqueue instead of slow-work fscache: drop references to slow-work fscache: convert operation to use workqueue instead of slow-work fscache: convert object to use workqueue instead of slow-work workqueue: fix how cpu number is stored in work->data workqueue: fix mayday_mask handling on UP workqueue: fix build problem on !CONFIG_SMP workqueue: fix locking in retry path of maybe_create_worker() async: use workqueue for worker pool workqueue: remove WQ_SINGLE_CPU and use WQ_UNBOUND instead workqueue: implement unbound workqueue workqueue: prepare for WQ_UNBOUND implementation libata: take advantage of cmwq and remove concurrency limitations workqueue: fix worker management invocation without pending works ... Fixed up conflicts in fs/cifs/* as per Tejun. Other trivial conflicts in include/linux/workqueue.h, kernel/trace/Kconfig and kernel/workqueue.c
Diffstat (limited to 'kernel')
-rw-r--r--kernel/Makefile2
-rw-r--r--kernel/async.c141
-rw-r--r--kernel/kthread.c164
-rw-r--r--kernel/power/process.c21
-rw-r--r--kernel/slow-work-debugfs.c227
-rw-r--r--kernel/slow-work.c1068
-rw-r--r--kernel/slow-work.h72
-rw-r--r--kernel/sysctl.c8
-rw-r--r--kernel/trace/Kconfig11
-rw-r--r--kernel/workqueue.c3160
-rw-r--r--kernel/workqueue_sched.h13
11 files changed, 2963 insertions, 1924 deletions
diff --git a/kernel/Makefile b/kernel/Makefile
index ce53fb2bd1d9..c53e491e25a8 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -99,8 +99,6 @@ obj-$(CONFIG_TRACING) += trace/
obj-$(CONFIG_X86_DS) += trace/
obj-$(CONFIG_RING_BUFFER) += trace/
obj-$(CONFIG_SMP) += sched_cpupri.o
-obj-$(CONFIG_SLOW_WORK) += slow-work.o
-obj-$(CONFIG_SLOW_WORK_DEBUG) += slow-work-debugfs.o
obj-$(CONFIG_PERF_EVENTS) += perf_event.o
obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o
obj-$(CONFIG_USER_RETURN_NOTIFIER) += user-return-notifier.o
diff --git a/kernel/async.c b/kernel/async.c
index 15319d6c18fe..cd9dbb913c77 100644
--- a/kernel/async.c
+++ b/kernel/async.c
@@ -49,40 +49,33 @@ asynchronous and synchronous parts of the kernel.
*/
#include <linux/async.h>
-#include <linux/bug.h>
#include <linux/module.h>
#include <linux/wait.h>
#include <linux/sched.h>
-#include <linux/init.h>
-#include <linux/kthread.h>
-#include <linux/delay.h>
#include <linux/slab.h>
+#include <linux/workqueue.h>
#include <asm/atomic.h>
static async_cookie_t next_cookie = 1;
-#define MAX_THREADS 256
#define MAX_WORK 32768
static LIST_HEAD(async_pending);
static LIST_HEAD(async_running);
static DEFINE_SPINLOCK(async_lock);
-static int async_enabled = 0;
-
struct async_entry {
- struct list_head list;
- async_cookie_t cookie;
- async_func_ptr *func;
- void *data;
- struct list_head *running;
+ struct list_head list;
+ struct work_struct work;
+ async_cookie_t cookie;
+ async_func_ptr *func;
+ void *data;
+ struct list_head *running;
};
static DECLARE_WAIT_QUEUE_HEAD(async_done);
-static DECLARE_WAIT_QUEUE_HEAD(async_new);
static atomic_t entry_count;
-static atomic_t thread_count;
extern int initcall_debug;
@@ -117,27 +110,23 @@ static async_cookie_t lowest_in_progress(struct list_head *running)
spin_unlock_irqrestore(&async_lock, flags);
return ret;
}
+
/*
* pick the first pending entry and run it
*/
-static void run_one_entry(void)
+static void async_run_entry_fn(struct work_struct *work)
{
+ struct async_entry *entry =
+ container_of(work, struct async_entry, work);
unsigned long flags;
- struct async_entry *entry;
ktime_t calltime, delta, rettime;
- /* 1) pick one task from the pending queue */
-
+ /* 1) move self to the running queue */
spin_lock_irqsave(&async_lock, flags);
- if (list_empty(&async_pending))
- goto out;
- entry = list_first_entry(&async_pending, struct async_entry, list);
-
- /* 2) move it to the running queue */
list_move_tail(&entry->list, entry->running);
spin_unlock_irqrestore(&async_lock, flags);
- /* 3) run it (and print duration)*/
+ /* 2) run (and print duration) */
if (initcall_debug && system_state == SYSTEM_BOOTING) {
printk("calling %lli_%pF @ %i\n", (long long)entry->cookie,
entry->func, task_pid_nr(current));
@@ -153,31 +142,25 @@ static void run_one_entry(void)
(long long)ktime_to_ns(delta) >> 10);
}
- /* 4) remove it from the running queue */
+ /* 3) remove self from the running queue */
spin_lock_irqsave(&async_lock, flags);
list_del(&entry->list);
- /* 5) free the entry */
+ /* 4) free the entry */
kfree(entry);
atomic_dec(&entry_count);
spin_unlock_irqrestore(&async_lock, flags);
- /* 6) wake up any waiters. */
+ /* 5) wake up any waiters */
wake_up(&async_done);
- return;
-
-out:
- spin_unlock_irqrestore(&async_lock, flags);
}
-
static async_cookie_t __async_schedule(async_func_ptr *ptr, void *data, struct list_head *running)
{
struct async_entry *entry;
unsigned long flags;
async_cookie_t newcookie;
-
/* allow irq-off callers */
entry = kzalloc(sizeof(struct async_entry), GFP_ATOMIC);
@@ -186,7 +169,7 @@ static async_cookie_t __async_schedule(async_func_ptr *ptr, void *data, struct l
* If we're out of memory or if there's too much work
* pending already, we execute synchronously.
*/
- if (!async_enabled || !entry || atomic_read(&entry_count) > MAX_WORK) {
+ if (!entry || atomic_read(&entry_count) > MAX_WORK) {
kfree(entry);
spin_lock_irqsave(&async_lock, flags);
newcookie = next_cookie++;
@@ -196,6 +179,7 @@ static async_cookie_t __async_schedule(async_func_ptr *ptr, void *data, struct l
ptr(data, newcookie);
return newcookie;
}
+ INIT_WORK(&entry->work, async_run_entry_fn);
entry->func = ptr;
entry->data = data;
entry->running = running;
@@ -205,7 +189,10 @@ static async_cookie_t __async_schedule(async_func_ptr *ptr, void *data, struct l
list_add_tail(&entry->list, &async_pending);
atomic_inc(&entry_count);
spin_unlock_irqrestore(&async_lock, flags);
- wake_up(&async_new);
+
+ /* schedule for execution */
+ queue_work(system_unbound_wq, &entry->work);
+
return newcookie;
}
@@ -312,87 +299,3 @@ void async_synchronize_cookie(async_cookie_t cookie)
async_synchronize_cookie_domain(cookie, &async_running);
}
EXPORT_SYMBOL_GPL(async_synchronize_cookie);
-
-
-static int async_thread(void *unused)
-{
- DECLARE_WAITQUEUE(wq, current);
- add_wait_queue(&async_new, &wq);
-
- while (!kthread_should_stop()) {
- int ret = HZ;
- set_current_state(TASK_INTERRUPTIBLE);
- /*
- * check the list head without lock.. false positives
- * are dealt with inside run_one_entry() while holding
- * the lock.
- */
- rmb();
- if (!list_empty(&async_pending))
- run_one_entry();
- else
- ret = schedule_timeout(HZ);
-
- if (ret == 0) {
- /*
- * we timed out, this means we as thread are redundant.
- * we sign off and die, but we to avoid any races there
- * is a last-straw check to see if work snuck in.
- */
- atomic_dec(&thread_count);
- wmb(); /* manager must see our departure first */
- if (list_empty(&async_pending))
- break;
- /*
- * woops work came in between us timing out and us
- * signing off; we need to stay alive and keep working.
- */
- atomic_inc(&thread_count);
- }
- }
- remove_wait_queue(&async_new, &wq);
-
- return 0;
-}
-
-static int async_manager_thread(void *unused)
-{
- DECLARE_WAITQUEUE(wq, current);
- add_wait_queue(&async_new, &wq);
-
- while (!kthread_should_stop()) {
- int tc, ec;
-
- set_current_state(TASK_INTERRUPTIBLE);
-
- tc = atomic_read(&thread_count);
- rmb();
- ec = atomic_read(&entry_count);
-
- while (tc < ec && tc < MAX_THREADS) {
- if (IS_ERR(kthread_run(async_thread, NULL, "async/%i",
- tc))) {
- msleep(100);
- continue;
- }
- atomic_inc(&thread_count);
- tc++;
- }
-
- schedule();
- }
- remove_wait_queue(&async_new, &wq);
-
- return 0;
-}
-
-static int __init async_init(void)
-{
- async_enabled =
- !IS_ERR(kthread_run(async_manager_thread, NULL, "async/mgr"));
-
- WARN_ON(!async_enabled);
- return 0;
-}
-
-core_initcall(async_init);
diff --git a/kernel/kthread.c b/kernel/kthread.c
index 83911c780175..2dc3786349d1 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -14,6 +14,8 @@
#include <linux/file.h>
#include <linux/module.h>
#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/freezer.h>
#include <trace/events/sched.h>
static DEFINE_SPINLOCK(kthread_create_lock);
@@ -35,6 +37,7 @@ struct kthread_create_info
struct kthread {
int should_stop;
+ void *data;
struct completion exited;
};
@@ -54,6 +57,19 @@ int kthread_should_stop(void)
}
EXPORT_SYMBOL(kthread_should_stop);
+/**
+ * kthread_data - return data value specified on kthread creation
+ * @task: kthread task in question
+ *
+ * Return the data value specified when kthread @task was created.
+ * The caller is responsible for ensuring the validity of @task when
+ * calling this function.
+ */
+void *kthread_data(struct task_struct *task)
+{
+ return to_kthread(task)->data;
+}
+
static int kthread(void *_create)
{
/* Copy data: it's on kthread's stack */
@@ -64,6 +80,7 @@ static int kthread(void *_create)
int ret;
self.should_stop = 0;
+ self.data = data;
init_completion(&self.exited);
current->vfork_done = &self.exited;
@@ -247,3 +264,150 @@ int kthreadd(void *unused)
return 0;
}
+
+/**
+ * kthread_worker_fn - kthread function to process kthread_worker
+ * @worker_ptr: pointer to initialized kthread_worker
+ *
+ * This function can be used as @threadfn to kthread_create() or
+ * kthread_run() with @worker_ptr argument pointing to an initialized
+ * kthread_worker. The started kthread will process work_list until
+ * the it is stopped with kthread_stop(). A kthread can also call
+ * this function directly after extra initialization.
+ *
+ * Different kthreads can be used for the same kthread_worker as long
+ * as there's only one kthread attached to it at any given time. A
+ * kthread_worker without an attached kthread simply collects queued
+ * kthread_works.
+ */
+int kthread_worker_fn(void *worker_ptr)
+{
+ struct kthread_worker *worker = worker_ptr;
+ struct kthread_work *work;
+
+ WARN_ON(worker->task);
+ worker->task = current;
+repeat:
+ set_current_state(TASK_INTERRUPTIBLE); /* mb paired w/ kthread_stop */
+
+ if (kthread_should_stop()) {
+ __set_current_state(TASK_RUNNING);
+ spin_lock_irq(&worker->lock);
+ worker->task = NULL;
+ spin_unlock_irq(&worker->lock);
+ return 0;
+ }
+
+ work = NULL;
+ spin_lock_irq(&worker->lock);
+ if (!list_empty(&worker->work_list)) {
+ work = list_first_entry(&worker->work_list,
+ struct kthread_work, node);
+ list_del_init(&work->node);
+ }
+ spin_unlock_irq(&worker->lock);
+
+ if (work) {
+ __set_current_state(TASK_RUNNING);
+ work->func(work);
+ smp_wmb(); /* wmb worker-b0 paired with flush-b1 */
+ work->done_seq = work->queue_seq;
+ smp_mb(); /* mb worker-b1 paired with flush-b0 */
+ if (atomic_read(&work->flushing))
+ wake_up_all(&work->done);
+ } else if (!freezing(current))
+ schedule();
+
+ try_to_freeze();
+ goto repeat;
+}
+EXPORT_SYMBOL_GPL(kthread_worker_fn);
+
+/**
+ * queue_kthread_work - queue a kthread_work
+ * @worker: target kthread_worker
+ * @work: kthread_work to queue
+ *
+ * Queue @work to work processor @task for async execution. @task
+ * must have been created with kthread_worker_create(). Returns %true
+ * if @work was successfully queued, %false if it was already pending.
+ */
+bool queue_kthread_work(struct kthread_worker *worker,
+ struct kthread_work *work)
+{
+ bool ret = false;
+ unsigned long flags;
+
+ spin_lock_irqsave(&worker->lock, flags);
+ if (list_empty(&work->node)) {
+ list_add_tail(&work->node, &worker->work_list);
+ work->queue_seq++;
+ if (likely(worker->task))
+ wake_up_process(worker->task);
+ ret = true;
+ }
+ spin_unlock_irqrestore(&worker->lock, flags);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(queue_kthread_work);
+
+/**
+ * flush_kthread_work - flush a kthread_work
+ * @work: work to flush
+ *
+ * If @work is queued or executing, wait for it to finish execution.
+ */
+void flush_kthread_work(struct kthread_work *work)
+{
+ int seq = work->queue_seq;
+
+ atomic_inc(&work->flushing);
+
+ /*
+ * mb flush-b0 paired with worker-b1, to make sure either
+ * worker sees the above increment or we see done_seq update.
+ */
+ smp_mb__after_atomic_inc();
+
+ /* A - B <= 0 tests whether B is in front of A regardless of overflow */
+ wait_event(work->done, seq - work->done_seq <= 0);
+ atomic_dec(&work->flushing);
+
+ /*
+ * rmb flush-b1 paired with worker-b0, to make sure our caller
+ * sees every change made by work->func().
+ */
+ smp_mb__after_atomic_dec();
+}
+EXPORT_SYMBOL_GPL(flush_kthread_work);
+
+struct kthread_flush_work {
+ struct kthread_work work;
+ struct completion done;
+};
+
+static void kthread_flush_work_fn(struct kthread_work *work)
+{
+ struct kthread_flush_work *fwork =
+ container_of(work, struct kthread_flush_work, work);
+ complete(&fwork->done);
+}
+
+/**
+ * flush_kthread_worker - flush all current works on a kthread_worker
+ * @worker: worker to flush
+ *
+ * Wait until all currently executing or pending works on @worker are
+ * finished.
+ */
+void flush_kthread_worker(struct kthread_worker *worker)
+{
+ struct kthread_flush_work fwork = {
+ KTHREAD_WORK_INIT(fwork.work, kthread_flush_work_fn),
+ COMPLETION_INITIALIZER_ONSTACK(fwork.done),
+ };
+
+ queue_kthread_work(worker, &fwork.work);
+ wait_for_completion(&fwork.done);
+}
+EXPORT_SYMBOL_GPL(flush_kthread_worker);
diff --git a/kernel/power/process.c b/kernel/power/process.c
index 71ae29052ab6..028a99598f49 100644
--- a/kernel/power/process.c
+++ b/kernel/power/process.c
@@ -15,6 +15,7 @@
#include <linux/syscalls.h>
#include <linux/freezer.h>
#include <linux/delay.h>
+#include <linux/workqueue.h>
/*
* Timeout for stopping processes
@@ -35,6 +36,7 @@ static int try_to_freeze_tasks(bool sig_only)
struct task_struct *g, *p;
unsigned long end_time;
unsigned int todo;
+ bool wq_busy = false;
struct timeval start, end;
u64 elapsed_csecs64;
unsigned int elapsed_csecs;
@@ -42,6 +44,10 @@ static int try_to_freeze_tasks(bool sig_only)
do_gettimeofday(&start);
end_time = jiffies + TIMEOUT;
+
+ if (!sig_only)
+ freeze_workqueues_begin();
+
while (true) {
todo = 0;
read_lock(&tasklist_lock);
@@ -63,6 +69,12 @@ static int try_to_freeze_tasks(bool sig_only)
todo++;
} while_each_thread(g, p);
read_unlock(&tasklist_lock);
+
+ if (!sig_only) {
+ wq_busy = freeze_workqueues_busy();
+ todo += wq_busy;
+ }
+
if (!todo || time_after(jiffies, end_time))
break;
@@ -86,8 +98,12 @@ static int try_to_freeze_tasks(bool sig_only)
*/
printk("\n");
printk(KERN_ERR "Freezing of tasks failed after %d.%02d seconds "
- "(%d tasks refusing to freeze):\n",
- elapsed_csecs / 100, elapsed_csecs % 100, todo);
+ "(%d tasks refusing to freeze, wq_busy=%d):\n",
+ elapsed_csecs / 100, elapsed_csecs % 100,
+ todo - wq_busy, wq_busy);
+
+ thaw_workqueues();
+
read_lock(&tasklist_lock);
do_each_thread(g, p) {
task_lock(p);
@@ -157,6 +173,7 @@ void thaw_processes(void)
oom_killer_enable();
printk("Restarting tasks ... ");
+ thaw_workqueues();
thaw_tasks(true);
thaw_tasks(false);
schedule();
diff --git a/kernel/slow-work-debugfs.c b/kernel/slow-work-debugfs.c
deleted file mode 100644
index e45c43645298..000000000000
--- a/kernel/slow-work-debugfs.c
+++ /dev/null
@@ -1,227 +0,0 @@
-/* Slow work debugging
- *
- * Copyright (C) 2009 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public Licence
- * as published by the Free Software Foundation; either version
- * 2 of the Licence, or (at your option) any later version.
- */
-
-#include <linux/module.h>
-#include <linux/slow-work.h>
-#include <linux/fs.h>
-#include <linux/time.h>
-#include <linux/seq_file.h>
-#include "slow-work.h"
-
-#define ITERATOR_SHIFT (BITS_PER_LONG - 4)
-#define ITERATOR_SELECTOR (0xfUL << ITERATOR_SHIFT)
-#define ITERATOR_COUNTER (~ITERATOR_SELECTOR)
-
-void slow_work_new_thread_desc(struct slow_work *work, struct seq_file *m)
-{
- seq_puts(m, "Slow-work: New thread");
-}
-
-/*
- * Render the time mark field on a work item into a 5-char time with units plus
- * a space
- */
-static void slow_work_print_mark(struct seq_file *m, struct slow_work *work)
-{
- struct timespec now, diff;
-
- now = CURRENT_TIME;
- diff = timespec_sub(now, work->mark);
-
- if (diff.tv_sec < 0)
- seq_puts(m, " -ve ");
- else if (diff.tv_sec == 0 && diff.tv_nsec < 1000)
- seq_printf(m, "%3luns ", diff.tv_nsec);
- else if (diff.tv_sec == 0 && diff.tv_nsec < 1000000)
- seq_printf(m, "%3luus ", diff.tv_nsec / 1000);
- else if (diff.tv_sec == 0 && diff.tv_nsec < 1000000000)
- seq_printf(m, "%3lums ", diff.tv_nsec / 1000000);
- else if (diff.tv_sec <= 1)
- seq_puts(m, " 1s ");
- else if (diff.tv_sec < 60)
- seq_printf(m, "%4lus ", diff.tv_sec);
- else if (diff.tv_sec < 60 * 60)
- seq_printf(m, "%4lum ", diff.tv_sec / 60);
- else if (diff.tv_sec < 60 * 60 * 24)
- seq_printf(m, "%4luh ", diff.tv_sec / 3600);
- else
- seq_puts(m, "exces ");
-}
-
-/*
- * Describe a slow work item for debugfs
- */
-static int slow_work_runqueue_show(struct seq_file *m, void *v)
-{
- struct slow_work *work;
- struct list_head *p = v;
- unsigned long id;
-
- switch ((unsigned long) v) {
- case 1:
- seq_puts(m, "THR PID ITEM ADDR FL MARK DESC\n");
- return 0;
- case 2:
- seq_puts(m, "=== ===== ================ == ===== ==========\n");
- return 0;
-
- case 3 ... 3 + SLOW_WORK_THREAD_LIMIT - 1:
- id = (unsigned long) v - 3;
-
- read_lock(&slow_work_execs_lock);
- work = slow_work_execs[id];
- if (work) {
- smp_read_barrier_depends();
-
- seq_printf(m, "%3lu %5d %16p %2lx ",
- id, slow_work_pids[id], work, work->flags);
- slow_work_print_mark(m, work);
-
- if (work->ops->desc)
- work->ops->desc(work, m);
- seq_putc(m, '\n');
- }
- read_unlock(&slow_work_execs_lock);
- return 0;
-
- default:
- work = list_entry(p, struct slow_work, link);
- seq_printf(m, "%3s - %16p %2lx ",
- work->flags & SLOW_WORK_VERY_SLOW ? "vsq" : "sq",
- work, work->flags);
- slow_work_print_mark(m, work);
-
- if (work->ops->desc)
- work->ops->desc(work, m);
- seq_putc(m, '\n');
- return 0;
- }
-}
-
-/*
- * map the iterator to a work item
- */
-static void *slow_work_runqueue_index(struct seq_file *m, loff_t *_pos)
-{
- struct list_head *p;
- unsigned long count, id;
-
- switch (*_pos >> ITERATOR_SHIFT) {
- case 0x0:
- if (*_pos == 0)
- *_pos = 1;
- if (*_pos < 3)
- return (void *)(unsigned long) *_pos;
- if (*_pos < 3 + SLOW_WORK_THREAD_LIMIT)
- for (id = *_pos - 3;
- id < SLOW_WORK_THREAD_LIMIT;
- id++, (*_pos)++)
- if (slow_work_execs[id])
- return (void *)(unsigned long) *_pos;
- *_pos = 0x1UL << ITERATOR_SHIFT;
-
- case 0x1:
- count = *_pos & ITERATOR_COUNTER;
- list_for_each(p, &slow_work_queue) {
- if (count == 0)
- return p;
- count--;
- }
- *_pos = 0x2UL << ITERATOR_SHIFT;
-
- case 0x2:
- count = *_pos & ITERATOR_COUNTER;
- list_for_each(p, &vslow_work_queue) {
- if (count == 0)
- return p;
- count--;
- }
- *_pos = 0x3UL << ITERATOR_SHIFT;
-
- default:
- return NULL;
- }
-}
-
-/*
- * set up the iterator to start reading from the first line
- */
-static void *slow_work_runqueue_start(struct seq_file *m, loff_t *_pos)
-{
- spin_lock_irq(&slow_work_queue_lock);
- return slow_work_runqueue_index(m, _pos);
-}
-
-/*
- * move to the next line
- */
-static void *slow_work_runqueue_next(struct seq_file *m, void *v, loff_t *_pos)
-{
- struct list_head *p = v;
- unsigned long selector = *_pos >> ITERATOR_SHIFT;
-
- (*_pos)++;
- switch (selector) {
- case 0x0:
- return slow_work_runqueue_index(m, _pos);
-
- case 0x1:
- if (*_pos >> ITERATOR_SHIFT == 0x1) {
- p = p->next;
- if (p != &slow_work_queue)
- return p;
- }
- *_pos = 0x2UL << ITERATOR_SHIFT;
- p = &vslow_work_queue;
-
- case 0x2:
- if (*_pos >> ITERATOR_SHIFT == 0x2) {
- p = p->next;
- if (p != &vslow_work_queue)
- return p;
- }
- *_pos = 0x3UL << ITERATOR_SHIFT;
-
- default:
- return NULL;
- }
-}
-
-/*
- * clean up after reading
- */
-static void slow_work_runqueue_stop(struct seq_file *m, void *v)
-{
- spin_unlock_irq(&slow_work_queue_lock);
-}
-
-static const struct seq_operations slow_work_runqueue_ops = {
- .start = slow_work_runqueue_start,
- .stop = slow_work_runqueue_stop,
- .next = slow_work_runqueue_next,
- .show = slow_work_runqueue_show,
-};
-
-/*
- * open "/sys/kernel/debug/slow_work/runqueue" to list queue contents
- */
-static int slow_work_runqueue_open(struct inode *inode, struct file *file)
-{
- return seq_open(file, &slow_work_runqueue_ops);
-}
-
-const struct file_operations slow_work_runqueue_fops = {
- .owner = THIS_MODULE,
- .open = slow_work_runqueue_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = seq_release,
-};
diff --git a/kernel/slow-work.c b/kernel/slow-work.c
deleted file mode 100644
index 7d3f4fa9ef4f..000000000000
--- a/kernel/slow-work.c
+++ /dev/null
@@ -1,1068 +0,0 @@
-/* Worker thread pool for slow items, such as filesystem lookups or mkdirs
- *
- * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public Licence
- * as published by the Free Software Foundation; either version
- * 2 of the Licence, or (at your option) any later version.
- *
- * See Documentation/slow-work.txt
- */
-
-#include <linux/module.h>
-#include <linux/slow-work.h>
-#include <linux/kthread.h>
-#include <linux/freezer.h>
-#include <linux/wait.h>
-#include <linux/debugfs.h>
-#include "slow-work.h"
-
-static void slow_work_cull_timeout(unsigned long);
-static void slow_work_oom_timeout(unsigned long);
-
-#ifdef CONFIG_SYSCTL
-static int slow_work_min_threads_sysctl(struct ctl_table *, int,
- void __user *, size_t *, loff_t *);
-
-static int slow_work_max_threads_sysctl(struct ctl_table *, int ,
- void __user *, size_t *, loff_t *);
-#endif
-
-/*
- * The pool of threads has at least min threads in it as long as someone is
- * using the facility, and may have as many as max.
- *
- * A portion of the pool may be processing very slow operations.
- */
-static unsigned slow_work_min_threads = 2;
-static unsigned slow_work_max_threads = 4;
-static unsigned vslow_work_proportion = 50; /* % of threads that may process
- * very slow work */
-
-#ifdef CONFIG_SYSCTL
-static const int slow_work_min_min_threads = 2;
-static int slow_work_max_max_threads = SLOW_WORK_THREAD_LIMIT;
-static const int slow_work_min_vslow = 1;
-static const int slow_work_max_vslow = 99;
-
-ctl_table slow_work_sysctls[] = {
- {
- .procname = "min-threads",
- .data = &slow_work_min_threads,
- .maxlen = sizeof(unsigned),
- .mode = 0644,
- .proc_handler = slow_work_min_threads_sysctl,
- .extra1 = (void *) &slow_work_min_min_threads,
- .extra2 = &slow_work_max_threads,
- },
- {
- .procname = "max-threads",
- .data = &slow_work_max_threads,
- .maxlen = sizeof(unsigned),
- .mode = 0644,
- .proc_handler = slow_work_max_threads_sysctl,
- .extra1 = &slow_work_min_threads,
- .extra2 = (void *) &slow_work_max_max_threads,
- },
- {
- .procname = "vslow-percentage",
- .data = &vslow_work_proportion,
- .maxlen = sizeof(unsigned),
- .mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = (void *) &slow_work_min_vslow,
- .extra2 = (void *) &slow_work_max_vslow,
- },
- {}
-};
-#endif
-
-/*
- * The active state of the thread pool
- */
-static atomic_t slow_work_thread_count;
-static atomic_t vslow_work_executing_count;
-
-static bool slow_work_may_not_start_new_thread;
-static bool slow_work_cull; /* cull a thread due to lack of activity */
-static DEFINE_TIMER(slow_work_cull_timer, slow_work_cull_timeout, 0, 0);
-static DEFINE_TIMER(slow_work_oom_timer, slow_work_oom_timeout, 0, 0);
-static struct slow_work slow_work_new_thread; /* new thread starter */
-
-/*
- * slow work ID allocation (use slow_work_queue_lock)
- */
-static DECLARE_BITMAP(slow_work_ids, SLOW_WORK_THREAD_LIMIT);
-
-/*
- * Unregistration tracking to prevent put_ref() from disappearing during module
- * unload
- */
-#ifdef CONFIG_MODULES
-static struct module *slow_work_thread_processing[SLOW_WORK_THREAD_LIMIT];
-static struct module *slow_work_unreg_module;
-static struct slow_work *slow_work_unreg_work_item;
-static DECLARE_WAIT_QUEUE_HEAD(slow_work_unreg_wq);
-static DEFINE_MUTEX(slow_work_unreg_sync_lock);
-
-static void slow_work_set_thread_processing(int id, struct slow_work *work)
-{
- if (work)
- slow_work_thread_processing[id] = work->owner;
-}
-static void slow_work_done_thread_processing(int id, struct slow_work *work)
-{
- struct module *module = slow_work_thread_processing[id];
-
- slow_work_thread_processing[id] = NULL;
- smp_mb();
- if (slow_work_unreg_work_item == work ||
- slow_work_unreg_module == module)
- wake_up_all(&slow_work_unreg_wq);
-}
-static void slow_work_clear_thread_processing(int id)
-{
- slow_work_thread_processing[id] = NULL;
-}
-#else
-static void slow_work_set_thread_processing(int id, struct slow_work *work) {}
-static void slow_work_done_thread_processing(int id, struct slow_work *work) {}
-static void slow_work_clear_thread_processing(int id) {}
-#endif
-
-/*
- * Data for tracking currently executing items for indication through /proc
- */
-#ifdef CONFIG_SLOW_WORK_DEBUG
-struct slow_work *slow_work_execs[SLOW_WORK_THREAD_LIMIT];
-pid_t slow_work_pids[SLOW_WORK_THREAD_LIMIT];
-DEFINE_RWLOCK(slow_work_execs_lock);
-#endif
-
-/*
- * The queues of work items and the lock governing access to them. These are
- * shared between all the CPUs. It doesn't make sense to have per-CPU queues
- * as the number of threads bears no relation to the number of CPUs.
- *
- * There are two queues of work items: one for slow work items, and one for
- * very slow work items.
- */
-LIST_HEAD(slow_work_queue);
-LIST_HEAD(vslow_work_queue);
-DEFINE_SPINLOCK(slow_work_queue_lock);
-
-/*
- * The following are two wait queues that get pinged when a work item is placed
- * on an empty queue. These allow work items that are hogging a thread by
- * sleeping in a way that could be deferred to yield their thread and enqueue
- * themselves.
- */
-static DECLARE_WAIT_QUEUE_HEAD(slow_work_queue_waits_for_occupation);
-static DECLARE_WAIT_QUEUE_HEAD(vslow_work_queue_waits_for_occupation);
-
-/*
- * The thread controls. A variable used to signal to the threads that they
- * should exit when the queue is empty, a waitqueue used by the threads to wait
- * for signals, and a completion set by the last thread to exit.
- */
-static bool slow_work_threads_should_exit;
-static DECLARE_WAIT_QUEUE_HEAD(slow_work_thread_wq);
-static DECLARE_COMPLETION(slow_work_last_thread_exited);
-
-/*
- * The number of users of the thread pool and its lock. Whilst this is zero we
- * have no threads hanging around, and when this reaches zero, we wait for all
- * active or queued work items to complete and kill all the threads we do have.
- */
-static int slow_work_user_count;
-static DEFINE_MUTEX(slow_work_user_lock);
-
-static inline int slow_work_get_ref(struct slow_work *work)
-{
- if (work->ops->get_ref)
- return work->ops->get_ref(work);
-
- return 0;
-}
-
-static inline void slow_work_put_ref(struct slow_work *work)
-{
- if (work->ops->put_ref)
- work->ops->put_ref(work);
-}
-
-/*
- * Calculate the maximum number of active threads in the pool that are
- * permitted to process very slow work items.
- *
- * The answer is rounded up to at least 1, but may not equal or exceed the
- * maximum number of the threads in the pool. This means we always have at
- * least one thread that can process slow work items, and we always have at
- * least one thread that won't get tied up doing so.
- */
-static unsigned slow_work_calc_vsmax(void)
-{
- unsigned vsmax;
-
- vsmax = atomic_read(&slow_work_thread_count) * vslow_work_proportion;
- vsmax /= 100;
- vsmax = max(vsmax, 1U);
- return min(vsmax, slow_work_max_threads - 1);
-}
-
-/*
- * Attempt to execute stuff queued on a slow thread. Return true if we managed
- * it, false if there was nothing to do.
- */
-static noinline bool slow_work_execute(int id)
-{
- struct slow_work *work = NULL;
- unsigned vsmax;
- bool very_slow;
-
- vsmax = slow_work_calc_vsmax();
-
- /* see if we can schedule a new thread to be started if we're not
- * keeping up with the work */
- if (!waitqueue_active(&slow_work_thread_wq) &&
- (!list_empty(&slow_work_queue) || !list_empty(&vslow_work_queue)) &&
- atomic_read(&slow_work_thread_count) < slow_work_max_threads &&
- !slow_work_may_not_start_new_thread)
- slow_work_enqueue(&slow_work_new_thread);
-
- /* find something to execute */
- spin_lock_irq(&slow_work_queue_lock);
- if (!list_empty(&vslow_work_queue) &&
- atomic_read(&vslow_work_executing_count) < vsmax) {
- work = list_entry(vslow_work_queue.next,
- struct slow_work, link);
- if (test_and_set_bit_lock(SLOW_WORK_EXECUTING, &work->flags))
- BUG();
- list_del_init(&work->link);
- atomic_inc(&vslow_work_executing_count);
- very_slow = true;
- } else if (!list_empty(&slow_work_queue)) {
- work = list_entry(slow_work_queue.next,
- struct slow_work, link);
- if (test_and_set_bit_lock(SLOW_WORK_EXECUTING, &work->flags))
- BUG();
- list_del_init(&work->link);
- very_slow = false;
- } else {
- very_slow = false; /* avoid the compiler warning */
- }
-
- slow_work_set_thread_processing(id, work);
- if (work) {
- slow_work_mark_time(work);
- slow_work_begin_exec(id, work);
- }
-
- spin_unlock_irq(&slow_work_queue_lock);
-
- if (!work)
- return false;
-
- if (!test_and_clear_bit(SLOW_WORK_PENDING, &work->flags))
- BUG();
-
- /* don't execute if the work is in the process of being cancelled */
- if (!test_bit(SLOW_WORK_CANCELLING, &work->flags))
- work->ops->execute(work);
-
- if (very_slow)
- atomic_dec(&vslow_work_executing_count);
- clear_bit_unlock(SLOW_WORK_EXECUTING, &work->flags);
-
- /* wake up anyone waiting for this work to be complete */
- wake_up_bit(&work->flags, SLOW_WORK_EXECUTING);
-
- slow_work_end_exec(id, work);
-
- /* if someone tried to enqueue the item whilst we were executing it,
- * then it'll be left unenqueued to a