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Commit 3b7433b8 authored by Linus Torvalds's avatar Linus Torvalds
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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
parents 4a386c3e 6ee0578b
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Showing with 3574 additions and 3009 deletions
Documentation/filesystems/caching/fscache.txt
View file @ 3b7433b8
......@@ -343,8 +343,8 @@ This will look something like:
[root@andromeda ~]# head /proc/fs/fscache/objects
OBJECT PARENT STAT CHLDN OPS OOP IPR EX READS EM EV F S | NETFS_COOKIE_DEF TY FL NETFS_DATA OBJECT_KEY, AUX_DATA
======== ======== ==== ===== === === === == ===== == == = = | ================ == == ================ ================
17e4b 2 ACTV 0 0 0 0 0 0 7b 4 0 8 | NFS.fh DT 0 ffff88001dd82820 010006017edcf8bbc93b43298fdfbe71e50b57b13a172c0117f38472, e567634700000000000000000000000063f2404a000000000000000000000000c9030000000000000000000063f2404a
1693a 2 ACTV 0 0 0 0 0 0 7b 4 0 8 | NFS.fh DT 0 ffff88002db23380 010006017edcf8bbc93b43298fdfbe71e50b57b1e0162c01a2df0ea6, 420ebc4a000000000000000000000000420ebc4a0000000000000000000000000e1801000000000000000000420ebc4a
17e4b 2 ACTV 0 0 0 0 0 0 7b 4 0 0 | NFS.fh DT 0 ffff88001dd82820 010006017edcf8bbc93b43298fdfbe71e50b57b13a172c0117f38472, e567634700000000000000000000000063f2404a000000000000000000000000c9030000000000000000000063f2404a
1693a 2 ACTV 0 0 0 0 0 0 7b 4 0 0 | NFS.fh DT 0 ffff88002db23380 010006017edcf8bbc93b43298fdfbe71e50b57b1e0162c01a2df0ea6, 420ebc4a000000000000000000000000420ebc4a0000000000000000000000000e1801000000000000000000420ebc4a
where the first set of columns before the '|' describe the object:
......@@ -362,7 +362,7 @@ where the first set of columns before the '|' describe the object:
EM Object's event mask
EV Events raised on this object
F Object flags
S Object slow-work work item flags
S Object work item busy state mask (1:pending 2:running)
and the second set of columns describe the object's cookie, if present:
......@@ -395,8 +395,8 @@ and the following paired letters:
w Show objects that don't have pending writes
R Show objects that have outstanding reads
r Show objects that don't have outstanding reads
S Show objects that have slow work queued
s Show objects that don't have slow work queued
S Show objects that have work queued
s Show objects that don't have work queued
If neither side of a letter pair is given, then both are implied. For example:
......
Documentation/slow-work.txt deleted 100644 → 0
View file @ 4a386c3e
====================================
SLOW WORK ITEM EXECUTION THREAD POOL
====================================
By: David Howells <dhowells@redhat.com>
The slow work item execution thread pool is a pool of threads for performing
things that take a relatively long time, such as making mkdir calls.
Typically, when processing something, these items will spend a lot of time
blocking a thread on I/O, thus making that thread unavailable for doing other
work.
The standard workqueue model is unsuitable for this class of work item as that
limits the owner to a single thread or a single thread per CPU. For some
tasks, however, more threads - or fewer - are required.
There is just one pool per system. It contains no threads unless something
wants to use it - and that something must register its interest first. When
the pool is active, the number of threads it contains is dynamic, varying
between a maximum and minimum setting, depending on the load.
====================
CLASSES OF WORK ITEM
====================
This pool support two classes of work items:
(*) Slow work items.
(*) Very slow work items.
The former are expected to finish much quicker than the latter.
An operation of the very slow class may do a batch combination of several
lookups, mkdirs, and a create for instance.
An operation of the ordinarily slow class may, for example, write stuff or
expand files, provided the time taken to do so isn't too long.
Operations of both types may sleep during execution, thus tying up the thread
loaned to it.
A further class of work item is available, based on the slow work item class:
(*) Delayed slow work items.
These are slow work items that have a timer to defer queueing of the item for
a while.
THREAD-TO-CLASS ALLOCATION
--------------------------
Not all the threads in the pool are available to work on very slow work items.
The number will be between one and one fewer than the number of active threads.
This is configurable (see the "Pool Configuration" section).
All the threads are available to work on ordinarily slow work items, but a
percentage of the threads will prefer to work on very slow work items.
The configuration ensures that at least one thread will be available to work on
very slow work items, and at least one thread will be available that won't work
on very slow work items at all.
=====================
USING SLOW WORK ITEMS
=====================
Firstly, a module or subsystem wanting to make use of slow work items must
register its interest:
int ret = slow_work_register_user(struct module *module);
This will return 0 if successful, or a -ve error upon failure. The module
pointer should be the module interested in using this facility (almost
certainly THIS_MODULE).
Slow work items may then be set up by:
(1) Declaring a slow_work struct type variable:
#include <linux/slow-work.h>
struct slow_work myitem;
(2) Declaring the operations to be used for this item:
struct slow_work_ops myitem_ops = {
.get_ref = myitem_get_ref,
.put_ref = myitem_put_ref,
.execute = myitem_execute,
};
[*] For a description of the ops, see section "Item Operations".
(3) Initialising the item:
slow_work_init(&myitem, &myitem_ops);
or:
delayed_slow_work_init(&myitem, &myitem_ops);
or:
vslow_work_init(&myitem, &myitem_ops);
depending on its class.
A suitably set up work item can then be enqueued for processing:
int ret = slow_work_enqueue(&myitem);
This will return a -ve error if the thread pool is unable to gain a reference
on the item, 0 otherwise, or (for delayed work):
int ret = delayed_slow_work_enqueue(&myitem, my_jiffy_delay);
The items are reference counted, so there ought to be no need for a flush
operation. But as the reference counting is optional, means to cancel
existing work items are also included:
cancel_slow_work(&myitem);
cancel_delayed_slow_work(&myitem);
can be used to cancel pending work. The above cancel function waits for
existing work to have been executed (or prevent execution of them, depending
on timing).
When all a module's slow work items have been processed, and the
module has no further interest in the facility, it should unregister its
interest:
slow_work_unregister_user(struct module *module);
The module pointer is used to wait for all outstanding work items for that
module before completing the unregistration. This prevents the put_ref() code
from being taken away before it completes. module should almost certainly be
THIS_MODULE.
================
HELPER FUNCTIONS
================
The slow-work facility provides a function by which it can be determined
whether or not an item is queued for later execution:
bool queued = slow_work_is_queued(struct slow_work *work);
If it returns false, then the item is not on the queue (it may be executing
with a requeue pending). This can be used to work out whether an item on which
another depends is on the queue, thus allowing a dependent item to be queued
after it.
If the above shows an item on which another depends not to be queued, then the
owner of the dependent item might need to wait. However, to avoid locking up
the threads unnecessarily be sleeping in them, it can make sense under some
circumstances to return the work item to the queue, thus deferring it until
some other items have had a chance to make use of the yielded thread.
To yield a thread and defer an item, the work function should simply enqueue
the work item again and return. However, this doesn't work if there's nothing
actually on the queue, as the thread just vacated will jump straight back into
the item's work function, thus busy waiting on a CPU.
Instead, the item should use the thread to wait for the dependency to go away,
but rather than using schedule() or schedule_timeout() to sleep, it should use
the following function:
bool requeue = slow_work_sleep_till_thread_needed(
struct slow_work *work,
signed long *_timeout);
This will add a second wait and then sleep, such that it will be woken up if
either something appears on the queue that could usefully make use of the
thread - and behind which this item can be queued, or if the event the caller
set up to wait for happens. True will be returned if something else appeared
on the queue and this work function should perhaps return, of false if
something else woke it up. The timeout is as for schedule_timeout().
For example:
wq = bit_waitqueue(&my_flags, MY_BIT);
init_wait(&wait);
requeue = false;
do {
prepare_to_wait(wq, &wait, TASK_UNINTERRUPTIBLE);
if (!test_bit(MY_BIT, &my_flags))
break;
requeue = slow_work_sleep_till_thread_needed(&my_work,
&timeout);
} while (timeout > 0 && !requeue);
finish_wait(wq, &wait);
if (!test_bit(MY_BIT, &my_flags)
goto do_my_thing;
if (requeue)
return; // to slow_work
===============
ITEM OPERATIONS
===============
Each work item requires a table of operations of type struct slow_work_ops.
Only ->execute() is required; the getting and putting of a reference and the
describing of an item are all optional.
(*) Get a reference on an item:
int (*get_ref)(struct slow_work *work);
This allows the thread pool to attempt to pin an item by getting a
reference on it. This function should return 0 if the reference was
granted, or a -ve error otherwise. If an error is returned,
slow_work_enqueue() will fail.
The reference is held whilst the item is queued and whilst it is being
executed. The item may then be requeued with the same reference held, or
the reference will be released.
(*) Release a reference on an item:
void (*put_ref)(struct slow_work *work);
This allows the thread pool to unpin an item by releasing the reference on
it. The thread pool will not touch the item again once this has been
called.
(*) Execute an item:
void (*execute)(struct slow_work *work);
This should perform the work required of the item. It may sleep, it may
perform disk I/O and it may wait for locks.
(*) View an item through /proc:
void (*desc)(struct slow_work *work, struct seq_file *m);
If supplied, this should print to 'm' a small string describing the work
the item is to do. This should be no more than about 40 characters, and
shouldn't include a newline character.
See the 'Viewing executing and queued items' section below.
==================
POOL CONFIGURATION
==================
The slow-work thread pool has a number of configurables:
(*) /proc/sys/kernel/slow-work/min-threads
The minimum number of threads that should be in the pool whilst it is in
use. This may be anywhere between 2 and max-threads.
(*) /proc/sys/kernel/slow-work/max-threads
The maximum number of threads that should in the pool. This may be
anywhere between min-threads and 255 or NR_CPUS * 2, whichever is greater.
(*) /proc/sys/kernel/slow-work/vslow-percentage
The percentage of active threads in the pool that may be used to execute
very slow work items. This may be between 1 and 99. The resultant number
is bounded to between 1 and one fewer than the number of active threads.
This ensures there is always at least one thread that can process very
slow work items, and always at least one thread that won't.
==================================
VIEWING EXECUTING AND QUEUED ITEMS
==================================
If CONFIG_SLOW_WORK_DEBUG is enabled, a debugfs file is made available:
/sys/kernel/debug/slow_work/runqueue
through which the list of work items being executed and the queues of items to
be executed may be viewed. The owner of a work item is given the chance to
add some information of its own.
The contents look something like the following:
THR PID ITEM ADDR FL MARK DESC
=== ===== ================ == ===== ==========
0 3005 ffff880023f52348 a 952ms FSC: OBJ17d3: LOOK
1 3006 ffff880024e33668 2 160ms FSC: OBJ17e5 OP60d3b: Write1/Store fl=2
2 3165 ffff8800296dd180 a 424ms FSC: OBJ17e4: LOOK
3 4089 ffff8800262c8d78 a 212ms FSC: OBJ17ea: CRTN
4 4090 ffff88002792bed8 2 388ms FSC: OBJ17e8 OP60d36: Write1/Store fl=2
5 4092 ffff88002a0ef308 2 388ms FSC: OBJ17e7 OP60d2e: Write1/Store fl=2
6 4094 ffff88002abaf4b8 2 132ms FSC: OBJ17e2 OP60d4e: Write1/Store fl=2
7 4095 ffff88002bb188e0 a 388ms FSC: OBJ17e9: CRTN
vsq - ffff880023d99668 1 308ms FSC: OBJ17e0 OP60f91: Write1/EnQ fl=2
vsq - ffff8800295d1740 1 212ms FSC: OBJ16be OP4d4b6: Write1/EnQ fl=2
vsq - ffff880025ba3308 1 160ms FSC: OBJ179a OP58dec: Write1/EnQ fl=2
vsq - ffff880024ec83e0 1 160ms FSC: OBJ17ae OP599f2: Write1/EnQ fl=2
vsq - ffff880026618e00 1 160ms FSC: OBJ17e6 OP60d33: Write1/EnQ fl=2
vsq - ffff880025a2a4b8 1 132ms FSC: OBJ16a2 OP4d583: Write1/EnQ fl=2
vsq - ffff880023cbe6d8 9 212ms FSC: OBJ17eb: LOOK
vsq - ffff880024d37590 9 212ms FSC: OBJ17ec: LOOK
vsq - ffff880027746cb0 9 212ms FSC: OBJ17ed: LOOK
vsq - ffff880024d37ae8 9 212ms FSC: OBJ17ee: LOOK
vsq - ffff880024d37cb0 9 212ms FSC: OBJ17ef: LOOK
vsq - ffff880025036550 9 212ms FSC: OBJ17f0: LOOK
vsq - ffff8800250368e0 9 212ms FSC: OBJ17f1: LOOK
vsq - ffff880025036aa8 9 212ms FSC: OBJ17f2: LOOK
In the 'THR' column, executing items show the thread they're occupying and
queued threads indicate which queue they're on. 'PID' shows the process ID of
a slow-work thread that's executing something. 'FL' shows the work item flags.
'MARK' indicates how long since an item was queued or began executing. Lastly,
the 'DESC' column permits the owner of an item to give some information.
arch/ia64/kernel/smpboot.c
View file @ 3b7433b8
......@@ -519,7 +519,7 @@ do_boot_cpu (int sapicid, int cpu)
/*
* We can't use kernel_thread since we must avoid to reschedule the child.
*/
if (!keventd_up() || current_is_keventd())
if (!keventd_up())
c_idle.work.func(&c_idle.work);
else {
schedule_work(&c_idle.work);
......
arch/x86/kernel/smpboot.c
View file @ 3b7433b8
......@@ -735,7 +735,7 @@ static int __cpuinit do_boot_cpu(int apicid, int cpu)
goto do_rest;
}
if (!keventd_up() || current_is_keventd())
if (!keventd_up())
c_idle.work.func(&c_idle.work);
else {
schedule_work(&c_idle.work);
......
drivers/acpi/osl.c
View file @ 3b7433b8
......@@ -191,36 +191,11 @@ acpi_status __init acpi_os_initialize(void)
return AE_OK;
}
static void bind_to_cpu0(struct work_struct *work)
{
set_cpus_allowed_ptr(current, cpumask_of(0));
kfree(work);
}
static void bind_workqueue(struct workqueue_struct *wq)
{
struct work_struct *work;
work = kzalloc(sizeof(struct work_struct), GFP_KERNEL);
INIT_WORK(work, bind_to_cpu0);
queue_work(wq, work);
}
acpi_status acpi_os_initialize1(void)
{
/*
* On some machines, a software-initiated SMI causes corruption unless
* the SMI runs on CPU 0. An SMI can be initiated by any AML, but
* typically it's done in GPE-related methods that are run via
* workqueues, so we can avoid the known corruption cases by binding
* the workqueues to CPU 0.
*/
kacpid_wq = create_singlethread_workqueue("kacpid");
bind_workqueue(kacpid_wq);
kacpi_notify_wq = create_singlethread_workqueue("kacpi_notify");
bind_workqueue(kacpi_notify_wq);
kacpi_hotplug_wq = create_singlethread_workqueue("kacpi_hotplug");
bind_workqueue(kacpi_hotplug_wq);
kacpid_wq = create_workqueue("kacpid");
kacpi_notify_wq = create_workqueue("kacpi_notify");
kacpi_hotplug_wq = create_workqueue("kacpi_hotplug");
BUG_ON(!kacpid_wq);
BUG_ON(!kacpi_notify_wq);
BUG_ON(!kacpi_hotplug_wq);
......@@ -766,7 +741,14 @@ static acpi_status __acpi_os_execute(acpi_execute_type type,
else
INIT_WORK(&dpc->work, acpi_os_execute_deferred);
ret = queue_work(queue, &dpc->work);
/*
* On some machines, a software-initiated SMI causes corruption unless
* the SMI runs on CPU 0. An SMI can be initiated by any AML, but
* typically it's done in GPE-related methods that are run via
* workqueues, so we can avoid the known corruption cases by always
* queueing on CPU 0.
*/
ret = queue_work_on(0, queue, &dpc->work);
if (!ret) {
printk(KERN_ERR PREFIX
......
drivers/ata/libata-core.c
View file @ 3b7433b8
......@@ -98,8 +98,6 @@ static unsigned long ata_dev_blacklisted(const struct ata_device *dev);
unsigned int ata_print_id = 1;
struct workqueue_struct *ata_aux_wq;
struct ata_force_param {
const char *name;
unsigned int cbl;
......@@ -5594,6 +5592,7 @@ struct ata_port *ata_port_alloc(struct ata_host *host)
ap->msg_enable = ATA_MSG_DRV | ATA_MSG_ERR | ATA_MSG_WARN;
#endif
mutex_init(&ap->scsi_scan_mutex);
INIT_DELAYED_WORK(&ap->hotplug_task, ata_scsi_hotplug);
INIT_WORK(&ap->scsi_rescan_task, ata_scsi_dev_rescan);
INIT_LIST_HEAD(&ap->eh_done_q);
......@@ -6532,29 +6531,20 @@ static int __init ata_init(void)
ata_parse_force_param();
ata_aux_wq = create_singlethread_workqueue("ata_aux");
if (!ata_aux_wq)
goto fail;
rc = ata_sff_init();
if (rc)
goto fail;
if (rc) {
kfree(ata_force_tbl);
return rc;
}
printk(KERN_DEBUG "libata version " DRV_VERSION " loaded.\n");
return 0;
fail:
kfree(ata_force_tbl);
if (ata_aux_wq)
destroy_workqueue(ata_aux_wq);
return rc;
}
static void __exit ata_exit(void)
{
ata_sff_exit();
kfree(ata_force_tbl);
destroy_workqueue(ata_aux_wq);
}
subsys_initcall(ata_init);
......
drivers/ata/libata-eh.c
View file @ 3b7433b8
......@@ -727,7 +727,7 @@ void ata_scsi_error(struct Scsi_Host *host)
if (ap->pflags & ATA_PFLAG_LOADING)
ap->pflags &= ~ATA_PFLAG_LOADING;
else if (ap->pflags & ATA_PFLAG_SCSI_HOTPLUG)
queue_delayed_work(ata_aux_wq, &ap->hotplug_task, 0);
schedule_delayed_work(&ap->hotplug_task, 0);
if (ap->pflags & ATA_PFLAG_RECOVERED)
ata_port_printk(ap, KERN_INFO, "EH complete\n");
......@@ -2945,7 +2945,7 @@ static int ata_eh_revalidate_and_attach(struct ata_link *link,
ehc->i.flags |= ATA_EHI_SETMODE;
/* schedule the scsi_rescan_device() here */
queue_work(ata_aux_wq, &(ap->scsi_rescan_task));
schedule_work(&(ap->scsi_rescan_task));
} else if (dev->class == ATA_DEV_UNKNOWN &&
ehc->tries[dev->devno] &&
ata_class_enabled(ehc->classes[dev->devno])) {
......
drivers/ata/libata-scsi.c
View file @ 3b7433b8
......@@ -3435,7 +3435,7 @@ void ata_scsi_scan_host(struct ata_port *ap, int sync)
" switching to async\n");
}
queue_delayed_work(ata_aux_wq, &ap->hotplug_task,
queue_delayed_work(system_long_wq, &ap->hotplug_task,
round_jiffies_relative(HZ));
}
......@@ -3582,6 +3582,7 @@ void ata_scsi_hotplug(struct work_struct *work)
}
DPRINTK("ENTER\n");
mutex_lock(&ap->scsi_scan_mutex);
/* Unplug detached devices. We cannot use link iterator here
* because PMP links have to be scanned even if PMP is
......@@ -3595,6 +3596,7 @@ void ata_scsi_hotplug(struct work_struct *work)
/* scan for new ones */
ata_scsi_scan_host(ap, 0);
mutex_unlock(&ap->scsi_scan_mutex);
DPRINTK("EXIT\n");
}
......@@ -3673,9 +3675,7 @@ static int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
* @work: Pointer to ATA port to perform scsi_rescan_device()
*
* After ATA pass thru (SAT) commands are executed successfully,
* libata need to propagate the changes to SCSI layer. This
* function must be executed from ata_aux_wq such that sdev
* attach/detach don't race with rescan.
* libata need to propagate the changes to SCSI layer.
*
* LOCKING:
* Kernel thread context (may sleep).
......@@ -3688,6 +3688,7 @@ void ata_scsi_dev_rescan(struct work_struct *work)
struct ata_device *dev;
unsigned long flags;
mutex_lock(&ap->scsi_scan_mutex);
spin_lock_irqsave(ap->lock, flags);
ata_for_each_link(link, ap, EDGE) {
......@@ -3707,6 +3708,7 @@ void ata_scsi_dev_rescan(struct work_struct *work)
}
spin_unlock_irqrestore(ap->lock, flags);
mutex_unlock(&ap->scsi_scan_mutex);
}
/**
......
drivers/ata/libata-sff.c
View file @ 3b7433b8
......@@ -3318,14 +3318,7 @@ void ata_sff_port_init(struct ata_port *ap)
int __init ata_sff_init(void)
{
/*
* FIXME: In UP case, there is only one workqueue thread and if you
* have more than one PIO device, latency is bloody awful, with
* occasional multi-second "hiccups" as one PIO device waits for
* another. It's an ugly wart that users DO occasionally complain
* about; luckily most users have at most one PIO polled device.
*/
ata_sff_wq = create_workqueue("ata_sff");
ata_sff_wq = alloc_workqueue("ata_sff", WQ_RESCUER, WQ_MAX_ACTIVE);
if (!ata_sff_wq)
return -ENOMEM;
......
drivers/ata/libata.h
View file @ 3b7433b8
......@@ -54,7 +54,6 @@ enum {
};
extern unsigned int ata_print_id;
extern struct workqueue_struct *ata_aux_wq;
extern int atapi_passthru16;
extern int libata_fua;
extern int libata_noacpi;
......
drivers/gpu/drm/drm_crtc_helper.c
View file @ 3b7433b8
......@@ -831,13 +831,11 @@ int drm_helper_resume_force_mode(struct drm_device *dev)
}
EXPORT_SYMBOL(drm_helper_resume_force_mode);
static struct slow_work_ops output_poll_ops;
#define DRM_OUTPUT_POLL_PERIOD (10*HZ)
static void output_poll_execute(struct slow_work *work)
static void output_poll_execute(struct work_struct *work)
{
struct delayed_slow_work *delayed_work = container_of(work, struct delayed_slow_work, work);
struct drm_device *dev = container_of(delayed_work, struct drm_device, mode_config.output_poll_slow_work);
struct delayed_work *delayed_work = to_delayed_work(work);
struct drm_device *dev = container_of(delayed_work, struct drm_device, mode_config.output_poll_work);
struct drm_connector *connector;
enum drm_connector_status old_status, status;
bool repoll = false, changed = false;
......@@ -877,7 +875,7 @@ static void output_poll_execute(struct slow_work *work)
}
if (repoll) {
ret = delayed_slow_work_enqueue(delayed_work, DRM_OUTPUT_POLL_PERIOD);
ret = queue_delayed_work(system_nrt_wq, delayed_work, DRM_OUTPUT_POLL_PERIOD);
if (ret)
DRM_ERROR("delayed enqueue failed %d\n", ret);
}
......@@ -887,7 +885,7 @@ void drm_kms_helper_poll_disable(struct drm_device *dev)
{
if (!dev->mode_config.poll_enabled)
return;
delayed_slow_work_cancel(&dev->mode_config.output_poll_slow_work);
cancel_delayed_work_sync(&dev->mode_config.output_poll_work);
}
EXPORT_SYMBOL(drm_kms_helper_poll_disable);
......@@ -903,7 +901,7 @@ void drm_kms_helper_poll_enable(struct drm_device *dev)
}
if (poll) {
ret = delayed_slow_work_enqueue(&dev->mode_config.output_poll_slow_work, DRM_OUTPUT_POLL_PERIOD);
ret = queue_delayed_work(system_nrt_wq, &dev->mode_config.output_poll_work, DRM_OUTPUT_POLL_PERIOD);
if (ret)
DRM_ERROR("delayed enqueue failed %d\n", ret);
}
......@@ -912,9 +910,7 @@ EXPORT_SYMBOL(drm_kms_helper_poll_enable);
void drm_kms_helper_poll_init(struct drm_device *dev)
{
slow_work_register_user(THIS_MODULE);
delayed_slow_work_init(&dev->mode_config.output_poll_slow_work,
&output_poll_ops);
INIT_DELAYED_WORK(&dev->mode_config.output_poll_work, output_poll_execute);
dev->mode_config.poll_enabled = true;
drm_kms_helper_poll_enable(dev);
......@@ -924,7 +920,6 @@ EXPORT_SYMBOL(drm_kms_helper_poll_init);
void drm_kms_helper_poll_fini(struct drm_device *dev)
{
drm_kms_helper_poll_disable(dev);
slow_work_unregister_user(THIS_MODULE);
}
EXPORT_SYMBOL(drm_kms_helper_poll_fini);
......@@ -932,12 +927,8 @@ void drm_helper_hpd_irq_event(struct drm_device *dev)
{
if (!dev->mode_config.poll_enabled)
return;
delayed_slow_work_cancel(&dev->mode_config.output_poll_slow_work);
/* schedule a slow work asap */
delayed_slow_work_enqueue(&dev->mode_config.output_poll_slow_work, 0);
/* kill timer and schedule immediate execution, this doesn't block */
cancel_delayed_work(&dev->mode_config.output_poll_work);
queue_delayed_work(system_nrt_wq, &dev->mode_config.output_poll_work, 0);
}
EXPORT_SYMBOL(drm_helper_hpd_irq_event);
static struct slow_work_ops output_poll_ops = {
.execute = output_poll_execute,
};
drivers/media/video/ivtv/ivtv-driver.c
View file @ 3b7433b8
......@@ -705,6 +705,8 @@ static void ivtv_process_options(struct ivtv *itv)
*/
static int __devinit ivtv_init_struct1(struct ivtv *itv)
{
struct sched_param param = { .sched_priority = 99 };
itv->base_addr = pci_resource_start(itv->pdev, 0);
itv->enc_mbox.max_mbox = 2; /* the encoder has 3 mailboxes (0-2) */
itv->dec_mbox.max_mbox = 1; /* the decoder has 2 mailboxes (0-1) */
......@@ -716,13 +718,17 @@ static int __devinit ivtv_init_struct1(struct ivtv *itv)
spin_lock_init(&itv->lock);
spin_lock_init(&itv->dma_reg_lock);
itv->irq_work_queues = create_singlethread_workqueue(itv->v4l2_dev.name);
if (itv->irq_work_queues == NULL) {
IVTV_ERR("Could not create ivtv workqueue\n");
init_kthread_worker(&itv->irq_worker);
itv->irq_worker_task = kthread_run(kthread_worker_fn, &itv->irq_worker,
itv->v4l2_dev.name);
if (IS_ERR(itv->irq_worker_task)) {
IVTV_ERR("Could not create ivtv task\n");
return -1;
}
/* must use the FIFO scheduler as it is realtime sensitive */
sched_setscheduler(itv->irq_worker_task, SCHED_FIFO, &param);
INIT_WORK(&itv->irq_work_queue, ivtv_irq_work_handler);
init_kthread_work(&itv->irq_work, ivtv_irq_work_handler);
/* start counting open_id at 1 */
itv->open_id = 1;
......@@ -1006,7 +1012,7 @@ static int __devinit ivtv_probe(struct pci_dev *pdev,
/* PCI Device Setup */
retval = ivtv_setup_pci(itv, pdev, pci_id);
if (retval == -EIO)
goto free_workqueue;
goto free_worker;
if (retval == -ENXIO)
goto free_mem;
......@@ -1218,8 +1224,8 @@ static int __devinit ivtv_probe(struct pci_dev *pdev,
release_mem_region(itv->base_addr + IVTV_REG_OFFSET, IVTV_REG_SIZE);
if (itv->has_cx23415)
release_mem_region(itv->base_addr + IVTV_DECODER_OFFSET, IVTV_DECODER_SIZE);
free_workqueue:
destroy_workqueue(itv->irq_work_queues);
free_worker:
kthread_stop(itv->irq_worker_task);
err:
if (retval == 0)
retval = -ENODEV;
......@@ -1363,9 +1369,9 @@ static void ivtv_remove(struct pci_dev *pdev)
ivtv_set_irq_mask(itv, 0xffffffff);
del_timer_sync(&itv->dma_timer);
/* Stop all Work Queues */
flush_workqueue(itv->irq_work_queues);
destroy_workqueue(itv->irq_work_queues);
/* Kill irq worker */
flush_kthread_worker(&itv->irq_worker);
kthread_stop(itv->irq_worker_task);
ivtv_streams_cleanup(itv, 1);
ivtv_udma_free(itv);
......
drivers/media/video/ivtv/ivtv-driver.h
View file @ 3b7433b8
......@@ -51,7 +51,7 @@
#include <linux/unistd.h>
#include <linux/pagemap.h>
#include <linux/scatterlist.h>
#include <linux/workqueue.h>
#include <linux/kthread.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <asm/uaccess.h>
......@@ -260,7 +260,6 @@ struct ivtv_mailbox_data {
#define IVTV_F_I_DEC_PAUSED 20 /* the decoder is paused */
#define IVTV_F_I_INITED 21 /* set after first open */
#define IVTV_F_I_FAILED 22 /* set if first open failed */
#define IVTV_F_I_WORK_INITED 23 /* worker thread was initialized */
/* Event notifications */
#define IVTV_F_I_EV_DEC_STOPPED 28 /* decoder stopped event */
......@@ -666,8 +665,9 @@ struct ivtv {
/* Interrupts & DMA */
u32 irqmask; /* active interrupts */
u32 irq_rr_idx; /* round-robin stream index */
struct workqueue_struct *irq_work_queues; /* workqueue for PIO/YUV/VBI actions */
struct work_struct irq_work_queue; /* work entry */
struct kthread_worker irq_worker; /* kthread worker for PIO/YUV/VBI actions */
struct task_struct *irq_worker_task; /* task for irq_worker */
struct kthread_work irq_work; /* kthread work entry */
spinlock_t dma_reg_lock; /* lock access to DMA engine registers */
int cur_dma_stream; /* index of current stream doing DMA (-1 if none) */
int cur_pio_stream; /* index of current stream doing PIO (-1 if none) */
......
drivers/media/video/ivtv/ivtv-irq.c
View file @ 3b7433b8
......@@ -71,19 +71,10 @@ static void ivtv_pio_work_handler(struct ivtv *itv)
write_reg(IVTV_IRQ_ENC_PIO_COMPLETE, 0x44);
}
void ivtv_irq_work_handler(struct work_struct *work)
void ivtv_irq_work_handler(struct kthread_work *work)
{
struct ivtv *itv = container_of(work, struct ivtv, irq_work_queue);
struct ivtv *itv = container_of(work, struct ivtv, irq_work);
DEFINE_WAIT(wait);
if (test_and_clear_bit(IVTV_F_I_WORK_INITED, &itv->i_flags)) {
struct sched_param param = { .sched_priority = 99 };
/* This thread must use the FIFO scheduler as it
is realtime sensitive. */
sched_setscheduler(current, SCHED_FIFO, &param);
}
if (test_and_clear_bit(IVTV_F_I_WORK_HANDLER_PIO, &itv->i_flags))
ivtv_pio_work_handler(itv);
......@@ -975,7 +966,7 @@ irqreturn_t ivtv_irq_handler(int irq, void *dev_id)
}
if (test_and_clear_bit(IVTV_F_I_HAVE_WORK, &itv->i_flags)) {
queue_work(itv->irq_work_queues, &itv->irq_work_queue);
queue_kthread_work(&itv->irq_worker, &itv->irq_work);
}
spin_unlock(&itv->dma_reg_lock);
......
drivers/media/video/ivtv/ivtv-irq.h
View file @ 3b7433b8
......@@ -46,7 +46,7 @@
irqreturn_t ivtv_irq_handler(int irq, void *dev_id);
void ivtv_irq_work_handler(struct work_struct *work);
void ivtv_irq_work_handler(struct kthread_work *work);
void ivtv_dma_stream_dec_prepare(struct ivtv_stream *s, u32 offset, int lock);
void ivtv_unfinished_dma(unsigned long arg);
......
fs/cachefiles/namei.c
View file @ 3b7433b8
......@@ -37,9 +37,9 @@ void __cachefiles_printk_object(struct cachefiles_object *object,
printk(KERN_ERR "%sobject: OBJ%x\n",
prefix, object->fscache.debug_id);
printk(KERN_ERR "%sobjstate=%s fl=%lx swfl=%lx ev=%lx[%lx]\n",
printk(KERN_ERR "%sobjstate=%s fl=%lx wbusy=%x ev=%lx[%lx]\n",
prefix, fscache_object_states[object->fscache.state],
object->fscache.flags, object->fscache.work.flags,
object->fscache.flags, work_busy(&object->fscache.work),
object->fscache.events,
object->fscache.event_mask & FSCACHE_OBJECT_EVENTS_MASK);
printk(KERN_ERR "%sops=%u inp=%u exc=%u\n",
......@@ -212,7 +212,7 @@ static int cachefiles_mark_object_active(struct cachefiles_cache *cache,
/* if the object we're waiting for is queued for processing,
* then just put ourselves on the queue behind it */
if (slow_work_is_queued(&xobject->fscache.work)) {
if (work_pending(&xobject->fscache.work)) {
_debug("queue OBJ%x behind OBJ%x immediately",
object->fscache.debug_id,
xobject->fscache.debug_id);
......@@ -220,8 +220,7 @@ static int cachefiles_mark_object_active(struct cachefiles_cache *cache,
}
/* otherwise we sleep until either the object we're waiting for
* is done, or the slow-work facility wants the thread back to
* do other work */
* is done, or the fscache_object is congested */
wq = bit_waitqueue(&xobject->flags, CACHEFILES_OBJECT_ACTIVE);
init_wait(&wait);
requeue = false;
......@@ -229,8 +228,8 @@ static int cachefiles_mark_object_active(struct cachefiles_cache *cache,
prepare_to_wait(wq, &wait, TASK_UNINTERRUPTIBLE);
if (!test_bit(CACHEFILES_OBJECT_ACTIVE, &xobject->flags))
break;
requeue = slow_work_sleep_till_thread_needed(
&object->fscache.work, &timeout);
requeue = fscache_object_sleep_till_congested(&timeout);
} while (timeout > 0 && !requeue);
finish_wait(wq, &wait);
......
fs/cachefiles/rdwr.c
View file @ 3b7433b8
......@@ -422,7 +422,7 @@ int cachefiles_read_or_alloc_page(struct fscache_retrieval *op,
shift = PAGE_SHIFT - inode->i_sb->s_blocksize_bits;
op->op.flags &= FSCACHE_OP_KEEP_FLAGS;
op->op.flags |= FSCACHE_OP_FAST;
op->op.flags |= FSCACHE_OP_ASYNC;
op->op.processor = cachefiles_read_copier;
pagevec_init(&pagevec, 0);
......@@ -729,7 +729,7 @@ int cachefiles_read_or_alloc_pages(struct fscache_retrieval *op,
pagevec_init(&pagevec, 0);
op->op.flags &= FSCACHE_OP_KEEP_FLAGS;
op->op.flags |= FSCACHE_OP_FAST;
op->op.flags |= FSCACHE_OP_ASYNC;
op->op.processor = cachefiles_read_copier;
INIT_LIST_HEAD(&backpages);
......
fs/cifs/Kconfig
View file @ 3b7433b8
......@@ -2,7 +2,6 @@ config CIFS
tristate "CIFS support (advanced network filesystem, SMBFS successor)"
depends on INET
select NLS
select SLOW_WORK
help
This is the client VFS module for the Common Internet File System
(CIFS) protocol which is the successor to the Server Message Block
......
fs/cifs/cifsfs.c
View file @ 3b7433b8
......@@ -939,15 +939,10 @@ init_cifs(void)
if (rc)
goto out_unregister_key_type;
#endif
rc = slow_work_register_user(THIS_MODULE);
if (rc)
goto out_unregister_resolver_key;
return 0;
out_unregister_resolver_key:
#ifdef CONFIG_CIFS_DFS_UPCALL
cifs_exit_dns_resolver();
out_unregister_key_type:
#endif
#ifdef CONFIG_CIFS_UPCALL
......
fs/cifs/cifsglob.h
View file @ 3b7433b8
......@@ -22,7 +22,7 @@
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/slab.h>
#include <linux/slow-work.h>
#include <linux/workqueue.h>
#include "cifs_fs_sb.h"
#include "cifsacl.h"
/*
......@@ -356,7 +356,7 @@ struct cifsFileInfo {
atomic_t count; /* reference count */
struct mutex fh_mutex; /* prevents reopen race after dead ses*/
struct cifs_search_info srch_inf;
struct slow_work oplock_break; /* slow_work job for oplock breaks */
struct work_struct oplock_break; /* work for oplock breaks */
};
/* Take a reference on the file private data */
......@@ -728,6 +728,10 @@ GLOBAL_EXTERN unsigned int cifs_min_rcv; /* min size of big ntwrk buf pool */
GLOBAL_EXTERN unsigned int cifs_min_small; /* min size of small buf pool */
GLOBAL_EXTERN unsigned int cifs_max_pending; /* MAX requests at once to server*/
void cifs_oplock_break(struct work_struct *work);
void cifs_oplock_break_get(struct cifsFileInfo *cfile);
void cifs_oplock_break_put(struct cifsFileInfo *cfile);
extern const struct slow_work_ops cifs_oplock_break_ops;
#endif /* _CIFS_GLOB_H */
fs/cifs/dir.c
View file @ 3b7433b8
......@@ -157,7 +157,7 @@ cifs_new_fileinfo(struct inode *newinode, __u16 fileHandle,
mutex_init(&pCifsFile->lock_mutex);
INIT_LIST_HEAD(&pCifsFile->llist);
atomic_set(&pCifsFile->count, 1);
slow_work_init(&pCifsFile->oplock_break, &cifs_oplock_break_ops);
INIT_WORK(&pCifsFile->oplock_break, cifs_oplock_break);
write_lock(&GlobalSMBSeslock);
list_add(&pCifsFile->tlist, &cifs_sb->tcon->openFileList);
......
fs/cifs/file.c
View file @ 3b7433b8
......@@ -2307,8 +2307,7 @@ static void cifs_invalidate_page(struct page *page, unsigned long offset)
cifs_fscache_invalidate_page(page, &cifsi->vfs_inode);
}
static void
cifs_oplock_break(struct slow_work *work)
void cifs_oplock_break(struct work_struct *work)
{
struct cifsFileInfo *cfile = container_of(work, struct cifsFileInfo,
oplock_break);
......@@ -2345,33 +2344,30 @@ cifs_oplock_break(struct slow_work *work)
LOCKING_ANDX_OPLOCK_RELEASE, false);
cFYI(1, "Oplock release rc = %d", rc);
}
/*
* We might have kicked in before is_valid_oplock_break()
* finished grabbing reference for us. Make sure it's done by
* waiting for GlobalSMSSeslock.
*/
write_lock(&GlobalSMBSeslock);
write_unlock(&GlobalSMBSeslock);
cifs_oplock_break_put(cfile);
}
static int
cifs_oplock_break_get(struct slow_work *work)
void cifs_oplock_break_get(struct cifsFileInfo *cfile)
{
struct cifsFileInfo *cfile = container_of(work, struct cifsFileInfo,
oplock_break);
mntget(cfile->mnt);
cifsFileInfo_get(cfile);
return 0;
}
static void
cifs_oplock_break_put(struct slow_work *work)
void cifs_oplock_break_put(struct cifsFileInfo *cfile)
{
struct cifsFileInfo *cfile = container_of(work, struct cifsFileInfo,
oplock_break);
mntput(cfile->mnt);
cifsFileInfo_put(cfile);
}
const struct slow_work_ops cifs_oplock_break_ops = {
.get_ref = cifs_oplock_break_get,
.put_ref = cifs_oplock_break_put,
.execute = cifs_oplock_break,
};
const struct address_space_operations cifs_addr_ops = {
.readpage = cifs_readpage,
.readpages = cifs_readpages,
......
fs/cifs/misc.c
View file @ 3b7433b8
......@@ -498,7 +498,6 @@ is_valid_oplock_break(struct smb_hdr *buf, struct TCP_Server_Info *srv)
struct cifsTconInfo *tcon;
struct cifsInodeInfo *pCifsInode;
struct cifsFileInfo *netfile;
int rc;
cFYI(1, "Checking for oplock break or dnotify response");
if ((pSMB->hdr.Command == SMB_COM_NT_TRANSACT) &&
......@@ -583,13 +582,18 @@ is_valid_oplock_break(struct smb_hdr *buf, struct TCP_Server_Info *srv)
pCifsInode->clientCanCacheAll = false;
if (pSMB->OplockLevel == 0)
pCifsInode->clientCanCacheRead = false;
rc = slow_work_enqueue(&netfile->oplock_break);
if (rc) {
cERROR(1, "failed to enqueue oplock "
"break: %d\n", rc);
} else {
netfile->oplock_break_cancelled = false;
}
/*
* cifs_oplock_break_put() can't be called
* from here. Get reference after queueing
* succeeded. cifs_oplock_break() will
* synchronize using GlobalSMSSeslock.
*/
if (queue_work(system_nrt_wq,
&netfile->oplock_break))
cifs_oplock_break_get(netfile);
netfile->oplock_break_cancelled = false;
read_unlock(&GlobalSMBSeslock);
read_unlock(&cifs_tcp_ses_lock);
return true;
......
fs/fscache/Kconfig
View file @ 3b7433b8
config FSCACHE
tristate "General filesystem local caching manager"
select SLOW_WORK
help
This option enables a generic filesystem caching manager that can be
used by various network and other filesystems to cache data locally.
......
fs/fscache/internal.h
View file @ 3b7433b8
......@@ -82,6 +82,14 @@ extern unsigned fscache_defer_lookup;
extern unsigned fscache_defer_create;
extern unsigned fscache_debug;
extern struct kobject *fscache_root;
extern struct workqueue_struct *fscache_object_wq;
extern struct workqueue_struct *fscache_op_wq;
DECLARE_PER_CPU(wait_queue_head_t, fscache_object_cong_wait);
static inline bool fscache_object_congested(void)
{
return workqueue_congested(WORK_CPU_UNBOUND, fscache_object_wq);
}
extern int fscache_wait_bit(void *);
extern int fscache_wait_bit_interruptible(void *);
......
fs/fscache/main.c
View file @ 3b7433b8
......@@ -15,6 +15,7 @@
#include <linux/sched.h>
#include <linux/completion.h>
#include <linux/slab.h>
#include <linux/seq_file.h>
#include "internal.h"
MODULE_DESCRIPTION("FS Cache Manager");
......@@ -40,22 +41,105 @@ MODULE_PARM_DESC(fscache_debug,
"FS-Cache debugging mask");
struct kobject *fscache_root;
struct workqueue_struct *fscache_object_wq;
struct workqueue_struct *fscache_op_wq;
DEFINE_PER_CPU(wait_queue_head_t, fscache_object_cong_wait);
/* these values serve as lower bounds, will be adjusted in fscache_init() */
static unsigned fscache_object_max_active = 4;
static unsigned fscache_op_max_active = 2;
#ifdef CONFIG_SYSCTL
static struct ctl_table_header *fscache_sysctl_header;
static int fscache_max_active_sysctl(struct ctl_table *table, int write,
void __user *buffer,
size_t *lenp, loff_t *ppos)
{
struct workqueue_struct **wqp = table->extra1;
unsigned int *datap = table->data;
int ret;
ret = proc_dointvec(table, write, buffer, lenp, ppos);
if (ret == 0)
workqueue_set_max_active(*wqp, *datap);
return ret;
}
ctl_table fscache_sysctls[] = {
{
.procname = "object_max_active",
.data = &fscache_object_max_active,
.maxlen = sizeof(unsigned),
.mode = 0644,
.proc_handler = fscache_max_active_sysctl,
.extra1 = &fscache_object_wq,
},
{
.procname = "operation_max_active",
.data = &fscache_op_max_active,
.maxlen = sizeof(unsigned),
.mode = 0644,
.proc_handler = fscache_max_active_sysctl,
.extra1 = &fscache_op_wq,
},
{}
};
ctl_table fscache_sysctls_root[] = {
{
.procname = "fscache",
.mode = 0555,
.child = fscache_sysctls,
},
{}
};
#endif
/*
* initialise the fs caching module
*/
static int __init fscache_init(void)
{
unsigned int nr_cpus = num_possible_cpus();
unsigned int cpu;
int ret;
ret = slow_work_register_user(THIS_MODULE);
if (ret < 0)
goto error_slow_work;
fscache_object_max_active =
clamp_val(nr_cpus,
fscache_object_max_active, WQ_UNBOUND_MAX_ACTIVE);
ret = -ENOMEM;
fscache_object_wq = alloc_workqueue("fscache_object", WQ_UNBOUND,
fscache_object_max_active);
if (!fscache_object_wq)
goto error_object_wq;
fscache_op_max_active =
clamp_val(fscache_object_max_active / 2,
fscache_op_max_active, WQ_UNBOUND_MAX_ACTIVE);
ret = -ENOMEM;
fscache_op_wq = alloc_workqueue("fscache_operation", WQ_UNBOUND,
fscache_op_max_active);
if (!fscache_op_wq)
goto error_op_wq;
for_each_possible_cpu(cpu)
init_waitqueue_head(&per_cpu(fscache_object_cong_wait, cpu));
ret = fscache_proc_init();
if (ret < 0)
goto error_proc;
#ifdef CONFIG_SYSCTL
ret = -ENOMEM;
fscache_sysctl_header = register_sysctl_table(fscache_sysctls_root);
if (!fscache_sysctl_header)
goto error_sysctl;
#endif
fscache_cookie_jar = kmem_cache_create("fscache_cookie_jar",
sizeof(struct fscache_cookie),
0,
......@@ -78,10 +162,16 @@ static int __init fscache_init(void)
error_kobj:
kmem_cache_destroy(fscache_cookie_jar);
error_cookie_jar:
#ifdef CONFIG_SYSCTL
unregister_sysctl_table(fscache_sysctl_header);
error_sysctl:
#endif
fscache_proc_cleanup();
error_proc:
slow_work_unregister_user(THIS_MODULE);
error_slow_work:
destroy_workqueue(fscache_op_wq);
error_op_wq:
destroy_workqueue(fscache_object_wq);
error_object_wq:
return ret;
}
......@@ -96,8 +186,12 @@ static void __exit fscache_exit(void)
kobject_put(fscache_root);
kmem_cache_destroy(fscache_cookie_jar);
#ifdef CONFIG_SYSCTL
unregister_sysctl_table(fscache_sysctl_header);
#endif
fscache_proc_cleanup();
slow_work_unregister_user(THIS_MODULE);
destroy_workqueue(fscache_op_wq);
destroy_workqueue(fscache_object_wq);
printk(KERN_NOTICE "FS-Cache: Unloaded\n");
}
......
fs/fscache/object-list.c
View file @ 3b7433b8
......@@ -34,8 +34,8 @@ struct fscache_objlist_data {
#define FSCACHE_OBJLIST_CONFIG_NOREADS 0x00000200 /* show objects without active reads */
#define FSCACHE_OBJLIST_CONFIG_EVENTS 0x00000400 /* show objects with events */
#define FSCACHE_OBJLIST_CONFIG_NOEVENTS 0x00000800 /* show objects without no events */
#define FSCACHE_OBJLIST_CONFIG_WORK 0x00001000 /* show objects with slow work */
#define FSCACHE_OBJLIST_CONFIG_NOWORK 0x00002000 /* show objects without slow work */
#define FSCACHE_OBJLIST_CONFIG_WORK 0x00001000 /* show objects with work */
#define FSCACHE_OBJLIST_CONFIG_NOWORK 0x00002000 /* show objects without work */
u8 buf[512]; /* key and aux data buffer */
};
......@@ -231,12 +231,11 @@ static int fscache_objlist_show(struct seq_file *m, void *v)
READS, NOREADS);
FILTER(obj->events & obj->event_mask,
EVENTS, NOEVENTS);
FILTER(obj->work.flags & ~(1UL << SLOW_WORK_VERY_SLOW),
WORK, NOWORK);
FILTER(work_busy(&obj->work), WORK, NOWORK);
}
seq_printf(m,
"%8x %8x %s %5u %3u %3u %3u %2u %5u %2lx %2lx %1lx %1lx | ",
"%8x %8x %s %5u %3u %3u %3u %2u %5u %2lx %2lx %1lx %1x | ",
obj->debug_id,
obj->parent ? obj->parent->debug_id : -1,
fscache_object_states_short[obj->state],
......@@ -249,7 +248,7 @@ static int fscache_objlist_show(struct seq_file *m, void *v)
obj->event_mask & FSCACHE_OBJECT_EVENTS_MASK,
obj->events,
obj->flags,
obj->work.flags);
work_busy(&obj->work));
no_cookie = true;
keylen = auxlen = 0;
......
fs/fscache/object.c
View file @ 3b7433b8
......@@ -14,7 +14,6 @@
#define FSCACHE_DEBUG_LEVEL COOKIE
#include <linux/module.h>
#include <linux/seq_file.h>
#include "internal.h"
const char *fscache_object_states[FSCACHE_OBJECT__NSTATES] = {
......@@ -50,12 +49,8 @@ const char fscache_object_states_short[FSCACHE_OBJECT__NSTATES][5] = {
[FSCACHE_OBJECT_DEAD] = "DEAD",
};
static void fscache_object_slow_work_put_ref(struct slow_work *);
static int fscache_object_slow_work_get_ref(struct slow_work *);
static void fscache_object_slow_work_execute(struct slow_work *);
#ifdef CONFIG_SLOW_WORK_DEBUG
static void fscache_object_slow_work_desc(struct slow_work *, struct seq_file *);
#endif
static int fscache_get_object(struct fscache_object *);
static void fscache_put_object(struct fscache_object *);
static void fscache_initialise_object(struct fscache_object *);
static void fscache_lookup_object(struct fscache_object *);
static void fscache_object_available(struct fscache_object *);
......@@ -64,17 +59,6 @@ static void fscache_withdraw_object(struct fscache_object *);
static void fscache_enqueue_dependents(struct fscache_object *);
static void fscache_dequeue_object(struct fscache_object *);
const struct slow_work_ops fscache_object_slow_work_ops = {
.owner = THIS_MODULE,
.get_ref = fscache_object_slow_work_get_ref,
.put_ref = fscache_object_slow_work_put_ref,
.execute = fscache_object_slow_work_execute,
#ifdef CONFIG_SLOW_WORK_DEBUG
.desc = fscache_object_slow_work_desc,
#endif
};
EXPORT_SYMBOL(fscache_object_slow_work_ops);
/*
* we need to notify the parent when an op completes that we had outstanding
* upon it
......@@ -345,7 +329,7 @@ static void fscache_object_state_machine(struct fscache_object *object)
/*
* execute an object
*/
static void fscache_object_slow_work_execute(struct slow_work *work)
void fscache_object_work_func(struct work_struct *work)
{
struct fscache_object *object =
container_of(work, struct fscache_object, work);
......@@ -359,23 +343,9 @@ static void fscache_object_slow_work_execute(struct slow_work *work)
if (object->events & object->event_mask)
fscache_enqueue_object(object);
clear_bit(FSCACHE_OBJECT_EV_REQUEUE, &object->events);
fscache_put_object(object);
}
/*
* describe an object for slow-work debugging
*/
#ifdef CONFIG_SLOW_WORK_DEBUG
static void fscache_object_slow_work_desc(struct slow_work *work,
struct seq_file *m)
{
struct fscache_object *object =
container_of(work, struct fscache_object, work);
seq_printf(m, "FSC: OBJ%x: %s",
object->debug_id,
fscache_object_states_short[object->state]);
}
#endif
EXPORT_SYMBOL(fscache_object_work_func);
/*
* initialise an object
......@@ -393,7 +363,6 @@ static void fscache_initialise_object(struct fscache_object *object)
_enter("");
ASSERT(object->cookie != NULL);
ASSERT(object->cookie->parent != NULL);
ASSERT(list_empty(&object->work.link));
if (object->events & ((1 << FSCACHE_OBJECT_EV_ERROR) |
(1 << FSCACHE_OBJECT_EV_RELEASE) |
......@@ -671,10 +640,8 @@ static void fscache_drop_object(struct fscache_object *object)
object->parent = NULL;
}
/* this just shifts the object release to the slow work processor */
fscache_stat(&fscache_n_cop_put_object);
object->cache->ops->put_object(object);
fscache_stat_d(&fscache_n_cop_put_object);
/* this just shifts the object release to the work processor */
fscache_put_object(object);
_leave("");
}
......@@ -758,12 +725,10 @@ void fscache_withdrawing_object(struct fscache_cache *cache,
}
/*
* allow the slow work item processor to get a ref on an object
* get a ref on an object
*/
static int fscache_object_slow_work_get_ref(struct slow_work *work)
static int fscache_get_object(struct fscache_object *object)
{
struct fscache_object *object =
container_of(work, struct fscache_object, work);
int ret;
fscache_stat(&fscache_n_cop_grab_object);
......@@ -773,13 +738,10 @@ static int fscache_object_slow_work_get_ref(struct slow_work *work)
}
/*
* allow the slow work item processor to discard a ref on a work item
* discard a ref on a work item
*/
static void fscache_object_slow_work_put_ref(struct slow_work *work)
static void fscache_put_object(struct fscache_object *object)
{
struct fscache_object *object =
container_of(work, struct fscache_object, work);
fscache_stat(&fscache_n_cop_put_object);
object->cache->ops->put_object(object);
fscache_stat_d(&fscache_n_cop_put_object);
......@@ -792,8 +754,48 @@ void fscache_enqueue_object(struct fscache_object *object)
{
_enter("{OBJ%x}", object->debug_id);
slow_work_enqueue(&object->work);
if (fscache_get_object(object) >= 0) {
wait_queue_head_t *cong_wq =
&get_cpu_var(fscache_object_cong_wait);
if (queue_work(fscache_object_wq, &object->work)) {
if (fscache_object_congested())
wake_up(cong_wq);
} else
fscache_put_object(object);
put_cpu_var(fscache_object_cong_wait);
}
}
/**
* fscache_object_sleep_till_congested - Sleep until object wq is congested
* @timoutp: Scheduler sleep timeout
*
* Allow an object handler to sleep until the object workqueue is congested.
*
* The caller must set up a wake up event before calling this and must have set
* the appropriate sleep mode (such as TASK_UNINTERRUPTIBLE) and tested its own
* condition before calling this function as no test is made here.
*
* %true is returned if the object wq is congested, %false otherwise.
*/
bool fscache_object_sleep_till_congested(signed long *timeoutp)
{
wait_queue_head_t *cong_wq = &__get_cpu_var(fscache_object_cong_wait);
DEFINE_WAIT(wait);
if (fscache_object_congested())
return true;
add_wait_queue_exclusive(cong_wq, &wait);
if (!fscache_object_congested())
*timeoutp = schedule_timeout(*timeoutp);
finish_wait(cong_wq, &wait);
return fscache_object_congested();
}
EXPORT_SYMBOL_GPL(fscache_object_sleep_till_congested);
/*
* enqueue the dependents of an object for metadata-type processing
......@@ -819,9 +821,7 @@ static void fscache_enqueue_dependents(struct fscache_object *object)
/* sort onto appropriate lists */
fscache_enqueue_object(dep);
fscache_stat(&fscache_n_cop_put_object);
dep->cache->ops->put_object(dep);
fscache_stat_d(&fscache_n_cop_put_object);
fscache_put_object(dep);
if (!list_empty(&object->dependents))
cond_resched_lock(&object->lock);
......
fs/fscache/operation.c
View file @ 3b7433b8
......@@ -42,16 +42,12 @@ void fscache_enqueue_operation(struct fscache_operation *op)
fscache_stat(&fscache_n_op_enqueue);
switch (op->flags & FSCACHE_OP_TYPE) {
case FSCACHE_OP_FAST:
_debug("queue fast");
case FSCACHE_OP_ASYNC:
_debug("queue async");
atomic_inc(&op->usage);
if (!schedule_work(&op->fast_work))
if (!queue_work(fscache_op_wq, &op->work))
fscache_put_operation(op);
break;
case FSCACHE_OP_SLOW:
_debug("queue slow");
slow_work_enqueue(&op->slow_work);
break;
case FSCACHE_OP_MYTHREAD:
_debug("queue for caller's attention");
break;
......@@ -455,36 +451,13 @@ void fscache_operation_gc(struct work_struct *work)
}
/*
* allow the slow work item processor to get a ref on an operation
*/
static int fscache_op_get_ref(struct slow_work *work)
{
struct fscache_operation *op =
container_of(work, struct fscache_operation, slow_work);
atomic_inc(&op->usage);
return 0;
}
/*
* allow the slow work item processor to discard a ref on an operation
*/
static void fscache_op_put_ref(struct slow_work *work)
{
struct fscache_operation *op =
container_of(work, struct fscache_operation, slow_work);
fscache_put_operation(op);
}
/*
* execute an operation using the slow thread pool to provide processing context
* - the caller holds a ref to this object, so we don't need to hold one
* execute an operation using fs_op_wq to provide processing context -
* the caller holds a ref to this object, so we don't need to hold one
*/
static void fscache_op_execute(struct slow_work *work)
void fscache_op_work_func(struct work_struct *work)
{
struct fscache_operation *op =
container_of(work, struct fscache_operation, slow_work);
container_of(work, struct fscache_operation, work);
unsigned long start;
_enter("{OBJ%x OP%x,%d}",
......@@ -494,31 +467,7 @@ static void fscache_op_execute(struct slow_work *work)
start = jiffies;
op->processor(op);
fscache_hist(fscache_ops_histogram, start);
fscache_put_operation(op);
_leave("");
}
/*
* describe an operation for slow-work debugging
*/
#ifdef CONFIG_SLOW_WORK_DEBUG
static void fscache_op_desc(struct slow_work *work, struct seq_file *m)
{
struct fscache_operation *op =
container_of(work, struct fscache_operation, slow_work);
seq_printf(m, "FSC: OBJ%x OP%x: %s/%s fl=%lx",
op->object->debug_id, op->debug_id,
op->name, op->state, op->flags);
}
#endif
const struct slow_work_ops fscache_op_slow_work_ops = {
.owner = THIS_MODULE,
.get_ref = fscache_op_get_ref,
.put_ref = fscache_op_put_ref,
.execute = fscache_op_execute,
#ifdef CONFIG_SLOW_WORK_DEBUG
.desc = fscache_op_desc,
#endif
};
fs/fscache/page.c
View file @ 3b7433b8
......@@ -105,7 +105,7 @@ bool __fscache_maybe_release_page(struct fscache_cookie *cookie,
page_busy:
/* we might want to wait here, but that could deadlock the allocator as
* the slow-work threads writing to the cache may all end up sleeping
* the work threads writing to the cache may all end up sleeping
* on memory allocation */
fscache_stat(&fscache_n_store_vmscan_busy);
return false;
......@@ -188,9 +188,8 @@ int __fscache_attr_changed(struct fscache_cookie *cookie)
return -ENOMEM;
}
fscache_operation_init(op, NULL);
fscache_operation_init_slow(op, fscache_attr_changed_op);
op->flags = FSCACHE_OP_SLOW | (1 << FSCACHE_OP_EXCLUSIVE);
fscache_operation_init(op, fscache_attr_changed_op, NULL);
op->flags = FSCACHE_OP_ASYNC | (1 << FSCACHE_OP_EXCLUSIVE);
fscache_set_op_name(op, "Attr");
spin_lock(&cookie->lock);
......@@ -217,24 +216,6 @@ int __fscache_attr_changed(struct fscache_cookie *cookie)
}
EXPORT_SYMBOL(__fscache_attr_changed);
/*
* handle secondary execution given to a retrieval op on behalf of the
* cache
*/
static void fscache_retrieval_work(struct work_struct *work)
{
struct fscache_retrieval *op =
container_of(work, struct fscache_retrieval, op.fast_work);
unsigned long start;
_enter("{OP%x}", op->op.debug_id);
start = jiffies;
op->op.processor(&op->op);
fscache_hist(fscache_ops_histogram, start);
fscache_put_operation(&op->op);
}
/*
* release a retrieval op reference
*/
......@@ -269,13 +250,12 @@ static struct fscache_retrieval *fscache_alloc_retrieval(
return NULL;
}
fscache_operation_init(&op->op, fscache_release_retrieval_op);
fscache_operation_init(&op->op, NULL, fscache_release_retrieval_op);
op->op.flags = FSCACHE_OP_MYTHREAD | (1 << FSCACHE_OP_WAITING);
op->mapping = mapping;
op->end_io_func = end_io_func;
op->context = context;
op->start_time = jiffies;
INIT_WORK(&op->op.fast_work, fscache_retrieval_work);
INIT_LIST_HEAD(&op->to_do);
fscache_set_op_name(&op->op, "Retr");
return op;
......@@ -795,9 +775,9 @@ int __fscache_write_page(struct fscache_cookie *cookie,
if (!op)
goto nomem;
fscache_operation_init(&op->op, fscache_release_write_op);
fscache_operation_init_slow(&op->op, fscache_write_op);
op->op.flags = FSCACHE_OP_SLOW | (1 << FSCACHE_OP_WAITING);
fscache_operation_init(&op->op, fscache_write_op,
fscache_release_write_op);
op->op.flags = FSCACHE_OP_ASYNC | (1 << FSCACHE_OP_WAITING);
fscache_set_op_name(&op->op, "Write1");
ret = radix_tree_preload(gfp & ~__GFP_HIGHMEM);
......@@ -852,7 +832,7 @@ int __fscache_write_page(struct fscache_cookie *cookie,
fscache_stat(&fscache_n_store_ops);
fscache_stat(&fscache_n_stores_ok);
/* the slow work queue now carries its own ref on the object */
/* the work queue now carries its own ref on the object */
fscache_put_operation(&op->op);
_leave(" = 0");
return 0;
......
fs/gfs2/Kconfig
View file @ 3b7433b8
......@@ -7,7 +7,6 @@ config GFS2_FS
select IP_SCTP if DLM_SCTP
select FS_POSIX_ACL
select CRC32
select SLOW_WORK
select QUOTACTL
help
A cluster filesystem.
......
fs/gfs2/incore.h
View file @ 3b7433b8
......@@ -12,7 +12,6 @@
#include <linux/fs.h>
#include <linux/workqueue.h>
#include <linux/slow-work.h>
#include <linux/dlm.h>
#include <linux/buffer_head.h>
......@@ -383,7 +382,7 @@ struct gfs2_journal_extent {
struct gfs2_jdesc {
struct list_head jd_list;
struct list_head extent_list;
struct slow_work jd_work;
struct work_struct jd_work;
struct inode *jd_inode;
unsigned long jd_flags;
#define JDF_RECOVERY 1
......
fs/gfs2/main.c
View file @ 3b7433b8
......@@ -15,7 +15,6 @@
#include <linux/init.h>
#include <linux/gfs2_ondisk.h>
#include <asm/atomic.h>
#include <linux/slow-work.h>
#include "gfs2.h"
#include "incore.h"
......@@ -24,6 +23,7 @@
#include "util.h"
#include "glock.h"
#include "quota.h"
#include "recovery.h"
static struct shrinker qd_shrinker = {
.shrink = gfs2_shrink_qd_memory,
......@@ -138,9 +138,11 @@ static int __init init_gfs2_fs(void)
if (error)
goto fail_unregister;
error = slow_work_register_user(THIS_MODULE);
if (error)
goto fail_slow;
error = -ENOMEM;
gfs_recovery_wq = alloc_workqueue("gfs_recovery",
WQ_NON_REENTRANT | WQ_RESCUER, 0);
if (!gfs_recovery_wq)
goto fail_wq;
gfs2_register_debugfs();
......@@ -148,7 +150,7 @@ static int __init init_gfs2_fs(void)
return 0;
fail_slow:
fail_wq:
unregister_filesystem(&gfs2meta_fs_type);
fail_unregister:
unregister_filesystem(&gfs2_fs_type);
......@@ -190,7 +192,7 @@ static void __exit exit_gfs2_fs(void)
gfs2_unregister_debugfs();
unregister_filesystem(&gfs2_fs_type);
unregister_filesystem(&gfs2meta_fs_type);
slow_work_unregister_user(THIS_MODULE);
destroy_workqueue(gfs_recovery_wq);
kmem_cache_destroy(gfs2_quotad_cachep);
kmem_cache_destroy(gfs2_rgrpd_cachep);
......
fs/gfs2/ops_fstype.c
View file @ 3b7433b8
......@@ -17,7 +17,6 @@
#include <linux/namei.h>
#include <linux/mount.h>
#include <linux/gfs2_ondisk.h>
#include <linux/slow-work.h>
#include <linux/quotaops.h>
#include "gfs2.h"
......@@ -673,7 +672,7 @@ static int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
break;
INIT_LIST_HEAD(&jd->extent_list);
slow_work_init(&jd->jd_work, &gfs2_recover_ops);
INIT_WORK(&jd->jd_work, gfs2_recover_func);
jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1);
if (!jd->jd_inode || IS_ERR(jd->jd_inode)) {
if (!jd->jd_inode)
......@@ -782,7 +781,8 @@ static int init_journal(struct gfs2_sbd *sdp, int undo)
if (sdp->sd_lockstruct.ls_first) {
unsigned int x;
for (x = 0; x < sdp->sd_journals; x++) {
error = gfs2_recover_journal(gfs2_jdesc_find(sdp, x));
error = gfs2_recover_journal(gfs2_jdesc_find(sdp, x),
true);
if (error) {
fs_err(sdp, "error recovering journal %u: %d\n",
x, error);
......@@ -792,7 +792,7 @@ static int init_journal(struct gfs2_sbd *sdp, int undo)
gfs2_others_may_mount(sdp);
} else if (!sdp->sd_args.ar_spectator) {
error = gfs2_recover_journal(sdp->sd_jdesc);
error = gfs2_recover_journal(sdp->sd_jdesc, true);
if (error) {
fs_err(sdp, "error recovering my journal: %d\n", error);
goto fail_jinode_gh;
......
fs/gfs2/recovery.c
View file @ 3b7433b8
......@@ -14,7 +14,6 @@
#include <linux/buffer_head.h>
#include <linux/gfs2_ondisk.h>
#include <linux/crc32.h>
#include <linux/slow-work.h>
#include "gfs2.h"
#include "incore.h"
......@@ -28,6 +27,8 @@
#include "util.h"
#include "dir.h"
struct workqueue_struct *gfs_recovery_wq;
int gfs2_replay_read_block(struct gfs2_jdesc *jd, unsigned int blk,
struct buffer_head **bh)
{
......@@ -443,23 +444,7 @@ static void gfs2_recovery_done(struct gfs2_sbd *sdp, unsigned int jid,
kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp);
}
static int gfs2_recover_get_ref(struct slow_work *work)
{
struct gfs2_jdesc *jd = container_of(work, struct gfs2_jdesc, jd_work);
if (test_and_set_bit(JDF_RECOVERY, &jd->jd_flags))
return -EBUSY;
return 0;
}
static void gfs2_recover_put_ref(struct slow_work *work)
{
struct gfs2_jdesc *jd = container_of(work, struct gfs2_jdesc, jd_work);
clear_bit(JDF_RECOVERY, &jd->jd_flags);
smp_mb__after_clear_bit();
wake_up_bit(&jd->jd_flags, JDF_RECOVERY);
}
static void gfs2_recover_work(struct slow_work *work)
void gfs2_recover_func(struct work_struct *work)
{
struct gfs2_jdesc *jd = container_of(work, struct gfs2_jdesc, jd_work);
struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
......@@ -578,7 +563,7 @@ static void gfs2_recover_work(struct slow_work *work)
gfs2_glock_dq_uninit(&j_gh);
fs_info(sdp, "jid=%u: Done\n", jd->jd_jid);
return;
goto done;
fail_gunlock_tr:
gfs2_glock_dq_uninit(&t_gh);
......@@ -590,32 +575,35 @@ static void gfs2_recover_work(struct slow_work *work)
}
fs_info(sdp, "jid=%u: %s\n", jd->jd_jid, (error) ? "Failed" : "Done");
fail:
gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_GAVEUP);
done:
clear_bit(JDF_RECOVERY, &jd->jd_flags);
smp_mb__after_clear_bit();
wake_up_bit(&jd->jd_flags, JDF_RECOVERY);
}
struct slow_work_ops gfs2_recover_ops = {
.owner = THIS_MODULE,
.get_ref = gfs2_recover_get_ref,
.put_ref = gfs2_recover_put_ref,
.execute = gfs2_recover_work,
};
static int gfs2_recovery_wait(void *word)
{
schedule();
return 0;
}
int gfs2_recover_journal(struct gfs2_jdesc *jd)
int gfs2_recover_journal(struct gfs2_jdesc *jd, bool wait)
{
int rv;
rv = slow_work_enqueue(&jd->jd_work);
if (rv)
return rv;
wait_on_bit(&jd->jd_flags, JDF_RECOVERY, gfs2_recovery_wait, TASK_UNINTERRUPTIBLE);
if (test_and_set_bit(JDF_RECOVERY, &jd->jd_flags))
return -EBUSY;
/* we have JDF_RECOVERY, queue should always succeed */
rv = queue_work(gfs_recovery_wq, &jd->jd_work);
BUG_ON(!rv);
if (wait)
wait_on_bit(&jd->jd_flags, JDF_RECOVERY, gfs2_recovery_wait,
TASK_UNINTERRUPTIBLE);
return 0;
}
fs/gfs2/recovery.h
View file @ 3b7433b8
......@@ -12,6 +12,8 @@
#include "incore.h"
extern struct workqueue_struct *gfs_recovery_wq;
static inline void gfs2_replay_incr_blk(struct gfs2_sbd *sdp, unsigned int *blk)
{
if (++*blk == sdp->sd_jdesc->jd_blocks)
......@@ -27,8 +29,8 @@ extern void gfs2_revoke_clean(struct gfs2_sbd *sdp);
extern int gfs2_find_jhead(struct gfs2_jdesc *jd,
struct gfs2_log_header_host *head);
extern int gfs2_recover_journal(struct gfs2_jdesc *gfs2_jd);
extern struct slow_work_ops gfs2_recover_ops;
extern int gfs2_recover_journal(struct gfs2_jdesc *gfs2_jd, bool wait);
extern void gfs2_recover_func(struct work_struct *work);
#endif /* __RECOVERY_DOT_H__ */
fs/gfs2/sys.c
View file @ 3b7433b8
......@@ -25,6 +25,7 @@
#include "quota.h"
#include "util.h"
#include "glops.h"
#include "recovery.h"
struct gfs2_attr {
struct attribute attr;
......@@ -376,7 +377,7 @@ static ssize_t recover_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
if (jd->jd_jid != jid)
continue;
rv = slow_work_enqueue(&jd->jd_work);
rv = gfs2_recover_journal(jd, false);
break;
}
out:
......
include/drm/drm_crtc.h
View file @ 3b7433b8
......@@ -31,7 +31,6 @@
#include <linux/idr.h>
#include <linux/fb.h>
#include <linux/slow-work.h>
struct drm_device;
struct drm_mode_set;
......@@ -595,7 +594,7 @@ struct drm_mode_config {
/* output poll support */
bool poll_enabled;
struct delayed_slow_work output_poll_slow_work;
struct delayed_work output_poll_work;
/* pointers to standard properties */
struct list_head property_blob_list;
......
include/linux/cpu.h
View file @ 3b7433b8
......@@ -71,6 +71,8 @@ enum {
/* migration should happen before other stuff but after perf */
CPU_PRI_PERF = 20,
CPU_PRI_MIGRATION = 10,
/* prepare workqueues for other notifiers */
CPU_PRI_WORKQUEUE = 5,
};
#ifdef CONFIG_SMP
......
include/linux/fscache-cache.h
View file @ 3b7433b8
......@@ -20,7 +20,7 @@
#include <linux/fscache.h>
#include <linux/sched.h>
#include <linux/slow-work.h>
#include <linux/workqueue.h>
#define NR_MAXCACHES BITS_PER_LONG
......@@ -76,18 +76,14 @@ typedef void (*fscache_operation_release_t)(struct fscache_operation *op);
typedef void (*fscache_operation_processor_t)(struct fscache_operation *op);
struct fscache_operation {
union {
struct work_struct fast_work; /* record for fast ops */
struct slow_work slow_work; /* record for (very) slow ops */
};
struct work_struct work; /* record for async ops */
struct list_head pend_link; /* link in object->pending_ops */
struct fscache_object *object; /* object to be operated upon */
unsigned long flags;
#define FSCACHE_OP_TYPE 0x000f /* operation type */
#define FSCACHE_OP_FAST 0x0001 /* - fast op, processor may not sleep for disk */
#define FSCACHE_OP_SLOW 0x0002 /* - (very) slow op, processor may sleep for disk */
#define FSCACHE_OP_MYTHREAD 0x0003 /* - processing is done be issuing thread, not pool */
#define FSCACHE_OP_ASYNC 0x0001 /* - async op, processor may sleep for disk */
#define FSCACHE_OP_MYTHREAD 0x0002 /* - processing is done be issuing thread, not pool */
#define FSCACHE_OP_WAITING 4 /* cleared when op is woken */
#define FSCACHE_OP_EXCLUSIVE 5 /* exclusive op, other ops must wait */
#define FSCACHE_OP_DEAD 6 /* op is now dead */
......@@ -105,7 +101,8 @@ struct fscache_operation {
/* operation releaser */
fscache_operation_release_t release;
#ifdef CONFIG_SLOW_WORK_DEBUG
#ifdef CONFIG_WORKQUEUE_DEBUGFS
struct work_struct put_work; /* work to delay operation put */
const char *name; /* operation name */
const char *state; /* operation state */
#define fscache_set_op_name(OP, N) do { (OP)->name = (N); } while(0)
......@@ -117,7 +114,7 @@ struct fscache_operation {
};
extern atomic_t fscache_op_debug_id;
extern const struct slow_work_ops fscache_op_slow_work_ops;
extern void fscache_op_work_func(struct work_struct *work);
extern void fscache_enqueue_operation(struct fscache_operation *);
extern void fscache_put_operation(struct fscache_operation *);
......@@ -128,33 +125,21 @@ extern void fscache_put_operation(struct fscache_operation *);
* @release: The release function to assign
*
* Do basic initialisation of an operation. The caller must still set flags,
* object, either fast_work or slow_work if necessary, and processor if needed.
* object and processor if needed.
*/
static inline void fscache_operation_init(struct fscache_operation *op,
fscache_operation_release_t release)
fscache_operation_processor_t processor,
fscache_operation_release_t release)
{
INIT_WORK(&op->work, fscache_op_work_func);
atomic_set(&op->usage, 1);
op->debug_id = atomic_inc_return(&fscache_op_debug_id);
op->processor = processor;
op->release = release;
INIT_LIST_HEAD(&op->pend_link);
fscache_set_op_state(op, "Init");
}
/**
* fscache_operation_init_slow - Do additional initialisation of a slow op
* @op: The operation to initialise
* @processor: The processor function to assign
*
* Do additional initialisation of an operation as required for slow work.
*/
static inline
void fscache_operation_init_slow(struct fscache_operation *op,
fscache_operation_processor_t processor)
{
op->processor = processor;
slow_work_init(&op->slow_work, &fscache_op_slow_work_ops);
}
/*
* data read operation
*/
......@@ -389,7 +374,7 @@ struct fscache_object {
struct fscache_cache *cache; /* cache that supplied this object */
struct fscache_cookie *cookie; /* netfs's file/index object */
struct fscache_object *parent; /* parent object */
struct slow_work work; /* attention scheduling record */
struct work_struct work; /* attention scheduling record */
struct list_head dependents; /* FIFO of dependent objects */
struct list_head dep_link; /* link in parent's dependents list */
struct list_head pending_ops; /* unstarted operations on this object */
......@@ -411,7 +396,7 @@ extern const char *fscache_object_states[];
(test_bit(FSCACHE_IOERROR, &(obj)->cache->flags) && \
(obj)->state >= FSCACHE_OBJECT_DYING)
extern const struct slow_work_ops fscache_object_slow_work_ops;
extern void fscache_object_work_func(struct work_struct *work);
/**
* fscache_object_init - Initialise a cache object description
......@@ -433,7 +418,7 @@ void fscache_object_init(struct fscache_object *object,
spin_lock_init(&object->lock);
INIT_LIST_HEAD(&object->cache_link);
INIT_HLIST_NODE(&object->cookie_link);
vslow_work_init(&object->work, &fscache_object_slow_work_ops);
INIT_WORK(&object->work, fscache_object_work_func);
INIT_LIST_HEAD(&object->dependents);
INIT_LIST_HEAD(&object->dep_link);
INIT_LIST_HEAD(&object->pending_ops);
......@@ -534,6 +519,8 @@ extern void fscache_io_error(struct fscache_cache *cache);
extern void fscache_mark_pages_cached(struct fscache_retrieval *op,
struct pagevec *pagevec);
extern bool fscache_object_sleep_till_congested(signed long *timeoutp);
extern enum fscache_checkaux fscache_check_aux(struct fscache_object *object,
const void *data,
uint16_t datalen);
......
include/linux/kthread.h
View file @ 3b7433b8
......@@ -30,8 +30,73 @@ struct task_struct *kthread_create(int (*threadfn)(void *data),
void kthread_bind(struct task_struct *k, unsigned int cpu);
int kthread_stop(struct task_struct *k);
int kthread_should_stop(void);
void *kthread_data(struct task_struct *k);
int kthreadd(void *unused);
extern struct task_struct *kthreadd_task;
/*
* Simple work processor based on kthread.
*
* This provides easier way to make use of kthreads. A kthread_work
* can be queued and flushed using queue/flush_kthread_work()
* respectively. Queued kthread_works are processed by a kthread
* running kthread_worker_fn().
*
* A kthread_work can't be freed while it is executing.
*/
struct kthread_work;
typedef void (*kthread_work_func_t)(struct kthread_work *work);
struct kthread_worker {
spinlock_t lock;
struct list_head work_list;
struct task_struct *task;
};
struct kthread_work {
struct list_head node;
kthread_work_func_t func;
wait_queue_head_t done;
atomic_t flushing;
int queue_seq;
int done_seq;
};
#define KTHREAD_WORKER_INIT(worker) { \
.lock = SPIN_LOCK_UNLOCKED, \
.work_list = LIST_HEAD_INIT((worker).work_list), \
}
#define KTHREAD_WORK_INIT(work, fn) { \
.node = LIST_HEAD_INIT((work).node), \
.func = (fn), \
.done = __WAIT_QUEUE_HEAD_INITIALIZER((work).done), \
.flushing = ATOMIC_INIT(0), \
}
#define DEFINE_KTHREAD_WORKER(worker) \
struct kthread_worker worker = KTHREAD_WORKER_INIT(worker)
#define DEFINE_KTHREAD_WORK(work, fn) \
struct kthread_work work = KTHREAD_WORK_INIT(work, fn)
static inline void init_kthread_worker(struct kthread_worker *worker)
{
*worker = (struct kthread_worker)KTHREAD_WORKER_INIT(*worker);
}
static inline void init_kthread_work(struct kthread_work *work,
kthread_work_func_t fn)
{
*work = (struct kthread_work)KTHREAD_WORK_INIT(*work, fn);
}
int kthread_worker_fn(void *worker_ptr);
bool queue_kthread_work(struct kthread_worker *worker,
struct kthread_work *work);
void flush_kthread_work(struct kthread_work *work);
void flush_kthread_worker(struct kthread_worker *worker);
#endif /* _LINUX_KTHREAD_H */
include/linux/libata.h
View file @ 3b7433b8
......@@ -751,6 +751,7 @@ struct ata_port {
struct ata_host *host;
struct device *dev;
struct mutex scsi_scan_mutex;
struct delayed_work hotplug_task;
struct work_struct scsi_rescan_task;
......
include/linux/slow-work.h deleted 100644 → 0
View file @ 4a386c3e
/* 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
*/
#ifndef _LINUX_SLOW_WORK_H
#define _LINUX_SLOW_WORK_H
#ifdef CONFIG_SLOW_WORK
#include <linux/sysctl.h>
#include <linux/timer.h>
struct slow_work;
#ifdef CONFIG_SLOW_WORK_DEBUG
struct seq_file;
#endif
/*
* The operations used to support slow work items
*/
struct slow_work_ops {
/* owner */
struct module *owner;
/* get a ref on a work item
* - return 0 if successful, -ve if not
*/
int (*get_ref)(struct slow_work *work);
/* discard a ref to a work item */
void (*put_ref)(struct slow_work *work);
/* execute a work item */
void (*execute)(struct slow_work *work);
#ifdef CONFIG_SLOW_WORK_DEBUG
/* describe a work item for debugfs */
void (*desc)(struct slow_work *work, struct seq_file *m);
#endif
};
/*
* A slow work item
* - A reference is held on the parent object by the thread pool when it is
* queued
*/
struct slow_work {
struct module *owner; /* the owning module */
unsigned long flags;
#define SLOW_WORK_PENDING 0 /* item pending (further) execution */
#define SLOW_WORK_EXECUTING 1 /* item currently executing */
#define SLOW_WORK_ENQ_DEFERRED 2 /* item enqueue deferred */
#define SLOW_WORK_VERY_SLOW 3 /* item is very slow */
#define SLOW_WORK_CANCELLING 4 /* item is being cancelled, don't enqueue */
#define SLOW_WORK_DELAYED 5 /* item is struct delayed_slow_work with active timer */
const struct slow_work_ops *ops; /* operations table for this item */
struct list_head link; /* link in queue */
#ifdef CONFIG_SLOW_WORK_DEBUG
struct timespec mark; /* jiffies at which queued or exec begun */
#endif
};
struct delayed_slow_work {
struct slow_work work;
struct timer_list timer;
};
/**
* slow_work_init - Initialise a slow work item
* @work: The work item to initialise
* @ops: The operations to use to handle the slow work item
*
* Initialise a slow work item.
*/
static inline void slow_work_init(struct slow_work *work,
const struct slow_work_ops *ops)
{
work->flags = 0;
work->ops = ops;
INIT_LIST_HEAD(&work->link);
}
/**
* slow_work_init - Initialise a delayed slow work item
* @work: The work item to initialise
* @ops: The operations to use to handle the slow work item
*
* Initialise a delayed slow work item.
*/
static inline void delayed_slow_work_init(struct delayed_slow_work *dwork,
const struct slow_work_ops *ops)
{
init_timer(&dwork->timer);
slow_work_init(&dwork->work, ops);
}
/**
* vslow_work_init - Initialise a very slow work item
* @work: The work item to initialise
* @ops: The operations to use to handle the slow work item
*
* Initialise a very slow work item. This item will be restricted such that
* only a certain number of the pool threads will be able to execute items of
* this type.
*/
static inline void vslow_work_init(struct slow_work *work,
const struct slow_work_ops *ops)
{
work->flags = 1 << SLOW_WORK_VERY_SLOW;
work->ops = ops;
INIT_LIST_HEAD(&work->link);
}
/**
* slow_work_is_queued - Determine if a slow work item is on the work queue
* work: The work item to test
*
* Determine if the specified slow-work item is on the work queue. This
* returns true if it is actually on the queue.
*
* If the item is executing and has been marked for requeue when execution
* finishes, then false will be returned.
*
* Anyone wishing to wait for completion of execution can wait on the
* SLOW_WORK_EXECUTING bit.
*/
static inline bool slow_work_is_queued(struct slow_work *work)
{
unsigned long flags = work->flags;
return flags & SLOW_WORK_PENDING && !(flags & SLOW_WORK_EXECUTING);
}
extern int slow_work_enqueue(struct slow_work *work);
extern void slow_work_cancel(struct slow_work *work);
extern int slow_work_register_user(struct module *owner);
extern void slow_work_unregister_user(struct module *owner);
extern int delayed_slow_work_enqueue(struct delayed_slow_work *dwork,
unsigned long delay);
static inline void delayed_slow_work_cancel(struct delayed_slow_work *dwork)
{
slow_work_cancel(&dwork->work);
}
extern bool slow_work_sleep_till_thread_needed(struct slow_work *work,
signed long *_timeout);
#ifdef CONFIG_SYSCTL
extern ctl_table slow_work_sysctls[];
#endif
#endif /* CONFIG_SLOW_WORK */
#endif /* _LINUX_SLOW_WORK_H */
include/linux/workqueue.h
View file @ 3b7433b8
......@@ -9,6 +9,7 @@
#include <linux/linkage.h>
#include <linux/bitops.h>
#include <linux/lockdep.h>
#include <linux/threads.h>
#include <asm/atomic.h>
struct workqueue_struct;
......@@ -22,12 +23,59 @@ typedef void (*work_func_t)(struct work_struct *work);
*/
#define work_data_bits(work) ((unsigned long *)(&(work)->data))
enum {
WORK_STRUCT_PENDING_BIT = 0, /* work item is pending execution */
WORK_STRUCT_CWQ_BIT = 1, /* data points to cwq */
WORK_STRUCT_LINKED_BIT = 2, /* next work is linked to this one */
#ifdef CONFIG_DEBUG_OBJECTS_WORK
WORK_STRUCT_STATIC_BIT = 3, /* static initializer (debugobjects) */
WORK_STRUCT_COLOR_SHIFT = 4, /* color for workqueue flushing */
#else
WORK_STRUCT_COLOR_SHIFT = 3, /* color for workqueue flushing */
#endif
WORK_STRUCT_COLOR_BITS = 4,
WORK_STRUCT_PENDING = 1 << WORK_STRUCT_PENDING_BIT,
WORK_STRUCT_CWQ = 1 << WORK_STRUCT_CWQ_BIT,
WORK_STRUCT_LINKED = 1 << WORK_STRUCT_LINKED_BIT,
#ifdef CONFIG_DEBUG_OBJECTS_WORK
WORK_STRUCT_STATIC = 1 << WORK_STRUCT_STATIC_BIT,
#else
WORK_STRUCT_STATIC = 0,
#endif
/*
* The last color is no color used for works which don't
* participate in workqueue flushing.
*/
WORK_NR_COLORS = (1 << WORK_STRUCT_COLOR_BITS) - 1,
WORK_NO_COLOR = WORK_NR_COLORS,
/* special cpu IDs */
WORK_CPU_UNBOUND = NR_CPUS,
WORK_CPU_NONE = NR_CPUS + 1,
WORK_CPU_LAST = WORK_CPU_NONE,
/*
* Reserve 7 bits off of cwq pointer w/ debugobjects turned
* off. This makes cwqs aligned to 128 bytes which isn't too
* excessive while allowing 15 workqueue flush colors.
*/
WORK_STRUCT_FLAG_BITS = WORK_STRUCT_COLOR_SHIFT +
WORK_STRUCT_COLOR_BITS,
WORK_STRUCT_FLAG_MASK = (1UL << WORK_STRUCT_FLAG_BITS) - 1,
WORK_STRUCT_WQ_DATA_MASK = ~WORK_STRUCT_FLAG_MASK,
WORK_STRUCT_NO_CPU = WORK_CPU_NONE << WORK_STRUCT_FLAG_BITS,
/* bit mask for work_busy() return values */
WORK_BUSY_PENDING = 1 << 0,
WORK_BUSY_RUNNING = 1 << 1,
};
struct work_struct {
atomic_long_t data;
#define WORK_STRUCT_PENDING 0 /* T if work item pending execution */
#define WORK_STRUCT_STATIC 1 /* static initializer (debugobjects) */
#define WORK_STRUCT_FLAG_MASK (3UL)
#define WORK_STRUCT_WQ_DATA_MASK (~WORK_STRUCT_FLAG_MASK)
struct list_head entry;
work_func_t func;
#ifdef CONFIG_LOCKDEP
......@@ -35,8 +83,9 @@ struct work_struct {
#endif
};
#define WORK_DATA_INIT() ATOMIC_LONG_INIT(0)
#define WORK_DATA_STATIC_INIT() ATOMIC_LONG_INIT(2)
#define WORK_DATA_INIT() ATOMIC_LONG_INIT(WORK_STRUCT_NO_CPU)
#define WORK_DATA_STATIC_INIT() \
ATOMIC_LONG_INIT(WORK_STRUCT_NO_CPU | WORK_STRUCT_STATIC)
struct delayed_work {
struct work_struct work;
......@@ -96,9 +145,14 @@ struct execute_work {
#ifdef CONFIG_DEBUG_OBJECTS_WORK
extern void __init_work(struct work_struct *work, int onstack);
extern void destroy_work_on_stack(struct work_struct *work);
static inline unsigned int work_static(struct work_struct *work)
{
return *work_data_bits(work) & WORK_STRUCT_STATIC;
}
#else
static inline void __init_work(struct work_struct *work, int onstack) { }
static inline void destroy_work_on_stack(struct work_struct *work) { }
static inline unsigned int work_static(struct work_struct *work) { return 0; }
#endif
/*
......@@ -162,7 +216,7 @@ static inline void destroy_work_on_stack(struct work_struct *work) { }
* @work: The work item in question
*/
#define work_pending(work) \
test_bit(WORK_STRUCT_PENDING, work_data_bits(work))
test_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))
/**
* delayed_work_pending - Find out whether a delayable work item is currently
......@@ -177,16 +231,56 @@ static inline void destroy_work_on_stack(struct work_struct *work) { }
* @work: The work item in question
*/
#define work_clear_pending(work) \
clear_bit(WORK_STRUCT_PENDING, work_data_bits(work))
clear_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))
enum {
WQ_NON_REENTRANT = 1 << 0, /* guarantee non-reentrance */
WQ_UNBOUND = 1 << 1, /* not bound to any cpu */
WQ_FREEZEABLE = 1 << 2, /* freeze during suspend */
WQ_RESCUER = 1 << 3, /* has an rescue worker */
WQ_HIGHPRI = 1 << 4, /* high priority */
WQ_CPU_INTENSIVE = 1 << 5, /* cpu instensive workqueue */
WQ_MAX_ACTIVE = 512, /* I like 512, better ideas? */
WQ_MAX_UNBOUND_PER_CPU = 4, /* 4 * #cpus for unbound wq */
WQ_DFL_ACTIVE = WQ_MAX_ACTIVE / 2,
};
/* unbound wq's aren't per-cpu, scale max_active according to #cpus */
#define WQ_UNBOUND_MAX_ACTIVE \
max_t(int, WQ_MAX_ACTIVE, num_possible_cpus() * WQ_MAX_UNBOUND_PER_CPU)
/*
* System-wide workqueues which are always present.
*
* system_wq is the one used by schedule[_delayed]_work[_on]().
* Multi-CPU multi-threaded. There are users which expect relatively
* short queue flush time. Don't queue works which can run for too
* long.
*
* system_long_wq is similar to system_wq but may host long running
* works. Queue flushing might take relatively long.
*
* system_nrt_wq is non-reentrant and guarantees that any given work
* item is never executed in parallel by multiple CPUs. Queue
* flushing might take relatively long.
*
* system_unbound_wq is unbound workqueue. Workers are not bound to
* any specific CPU, not concurrency managed, and all queued works are
* executed immediately as long as max_active limit is not reached and
* resources are available.
*/
extern struct workqueue_struct *system_wq;
extern struct workqueue_struct *system_long_wq;
extern struct workqueue_struct *system_nrt_wq;
extern struct workqueue_struct *system_unbound_wq;
extern struct workqueue_struct *
__create_workqueue_key(const char *name, int singlethread,
int freezeable, int rt, struct lock_class_key *key,
const char *lock_name);
__alloc_workqueue_key(const char *name, unsigned int flags, int max_active,
struct lock_class_key *key, const char *lock_name);
#ifdef CONFIG_LOCKDEP
#define __create_workqueue(name, singlethread, freezeable, rt) \
#define alloc_workqueue(name, flags, max_active) \
({ \
static struct lock_class_key __key; \
const char *__lock_name; \
......@@ -196,20 +290,20 @@ __create_workqueue_key(const char *name, int singlethread,
else \
__lock_name = #name; \
\
__create_workqueue_key((name), (singlethread), \
(freezeable), (rt), &__key, \
__lock_name); \
__alloc_workqueue_key((name), (flags), (max_active), \
&__key, __lock_name); \
})
#else
#define __create_workqueue(name, singlethread, freezeable, rt) \
__create_workqueue_key((name), (singlethread), (freezeable), (rt), \
NULL, NULL)
#define alloc_workqueue(name, flags, max_active) \
__alloc_workqueue_key((name), (flags), (max_active), NULL, NULL)
#endif
#define create_workqueue(name) __create_workqueue((name), 0, 0, 0)
#define create_rt_workqueue(name) __create_workqueue((name), 0, 0, 1)
#define create_freezeable_workqueue(name) __create_workqueue((name), 1, 1, 0)
#define create_singlethread_workqueue(name) __create_workqueue((name), 1, 0, 0)
#define create_workqueue(name) \
alloc_workqueue((name), WQ_RESCUER, 1)
#define create_freezeable_workqueue(name) \
alloc_workqueue((name), WQ_FREEZEABLE | WQ_UNBOUND | WQ_RESCUER, 1)
#define create_singlethread_workqueue(name) \
alloc_workqueue((name), WQ_UNBOUND | WQ_RESCUER, 1)
extern void destroy_workqueue(struct workqueue_struct *wq);
......@@ -231,16 +325,19 @@ extern int schedule_delayed_work(struct delayed_work *work, unsigned long delay)
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 current_is_keventd(void);
extern int keventd_up(void);
extern void init_workqueues(void);
int execute_in_process_context(work_func_t fn, struct execute_work *);
extern int flush_work(struct work_struct *work);
extern int cancel_work_sync(struct work_struct *work);
extern void workqueue_set_max_active(struct workqueue_struct *wq,
int max_active);
extern bool workqueue_congested(unsigned int cpu, struct workqueue_struct *wq);
extern unsigned int work_cpu(struct work_struct *work);
extern unsigned int work_busy(struct work_struct *work);
/*
* Kill off a pending schedule_delayed_work(). Note that the work callback
* function may still be running on return from cancel_delayed_work(), unless
......@@ -298,7 +395,14 @@ static inline long work_on_cpu(unsigned int cpu, long (*fn)(void *), void *arg)
long work_on_cpu(unsigned int cpu, long (*fn)(void *), void *arg);
#endif /* CONFIG_SMP */
#ifdef CONFIG_FREEZER
extern void freeze_workqueues_begin(void);
extern bool freeze_workqueues_busy(void);
extern void thaw_workqueues(void);
#endif /* CONFIG_FREEZER */
#ifdef CONFIG_LOCKDEP
int in_workqueue_context(struct workqueue_struct *wq);
#endif
#endif
include/trace/events/workqueue.h deleted 100644 → 0
View file @ 4a386c3e
#undef TRACE_SYSTEM
#define TRACE_SYSTEM workqueue
#if !defined(_TRACE_WORKQUEUE_H) || defined(TRACE_HEADER_MULTI_READ)
#define _TRACE_WORKQUEUE_H
#include <linux/workqueue.h>
#include <linux/sched.h>
#include <linux/tracepoint.h>
DECLARE_EVENT_CLASS(workqueue,
TP_PROTO(struct task_struct *wq_thread, struct work_struct *work),
TP_ARGS(wq_thread, work),
TP_STRUCT__entry(
__array(char, thread_comm, TASK_COMM_LEN)
__field(pid_t, thread_pid)
__field(work_func_t, func)
),
TP_fast_assign(
memcpy(__entry->thread_comm, wq_thread->comm, TASK_COMM_LEN);
__entry->thread_pid = wq_thread->pid;
__entry->func = work->func;
),
TP_printk("thread=%s:%d func=%pf", __entry->thread_comm,
__entry->thread_pid, __entry->func)
);
DEFINE_EVENT(workqueue, workqueue_insertion,
TP_PROTO(struct task_struct *wq_thread, struct work_struct *work),
TP_ARGS(wq_thread, work)
);
DEFINE_EVENT(workqueue, workqueue_execution,
TP_PROTO(struct task_struct *wq_thread, struct work_struct *work),
TP_ARGS(wq_thread, work)
);
/* Trace the creation of one workqueue thread on a cpu */
TRACE_EVENT(workqueue_creation,
TP_PROTO(struct task_struct *wq_thread, int cpu),
TP_ARGS(wq_thread, cpu),
TP_STRUCT__entry(
__array(char, thread_comm, TASK_COMM_LEN)
__field(pid_t, thread_pid)
__field(int, cpu)
),
TP_fast_assign(
memcpy(__entry->thread_comm, wq_thread->comm, TASK_COMM_LEN);
__entry->thread_pid = wq_thread->pid;
__entry->cpu = cpu;
),
TP_printk("thread=%s:%d cpu=%d", __entry->thread_comm,
__entry->thread_pid, __entry->cpu)
);
TRACE_EVENT(workqueue_destruction,
TP_PROTO(struct task_struct *wq_thread),
TP_ARGS(wq_thread),
TP_STRUCT__entry(
__array(char, thread_comm, TASK_COMM_LEN)
__field(pid_t, thread_pid)
),
TP_fast_assign(
memcpy(__entry->thread_comm, wq_thread->comm, TASK_COMM_LEN);
__entry->thread_pid = wq_thread->pid;
),
TP_printk("thread=%s:%d", __entry->thread_comm, __entry->thread_pid)
);
#endif /* _TRACE_WORKQUEUE_H */
/* This part must be outside protection */
#include <trace/define_trace.h>
init/Kconfig
View file @ 3b7433b8
......@@ -1143,30 +1143,6 @@ config TRACEPOINTS
source "arch/Kconfig"
config SLOW_WORK
default n
bool
help
The slow work thread pool provides a number of dynamically allocated
threads that can be used by the kernel to perform operations that
take a relatively long time.
An example of this would be CacheFiles doing a path lookup followed
by a series of mkdirs and a create call, all of which have to touch
disk.
See Documentation/slow-work.txt.
config SLOW_WORK_DEBUG
bool "Slow work debugging through debugfs"
default n
depends on SLOW_WORK && DEBUG_FS
help
Display the contents of the slow work run queue through debugfs,
including items currently executing.
See Documentation/slow-work.txt.
endmenu # General setup
config HAVE_GENERIC_DMA_COHERENT
......
init/main.c
View file @ 3b7433b8
......@@ -32,7 +32,6 @@
#include <linux/start_kernel.h>
#include <linux/security.h>
#include <linux/smp.h>
#include <linux/workqueue.h>
#include <linux/profile.h>
#include <linux/rcupdate.h>
#include <linux/moduleparam.h>
......@@ -789,7 +788,6 @@ static void __init do_initcalls(void)
*/
static void __init do_basic_setup(void)
{
init_workqueues();
cpuset_init_smp();
usermodehelper_init();
init_tmpfs();
......
kernel/Makefile
View file @ 3b7433b8
......@@ -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
......
kernel/async.c
View file @ 3b7433b8
......@@ -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);
kernel/kthread.c
View file @ 3b7433b8
......@@ -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);
kernel/power/process.c
View file @ 3b7433b8
......@@ -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();
......
kernel/slow-work-debugfs.c deleted 100644 → 0
View file @ 4a386c3e
/* 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,
};
kernel/slow-work.c deleted 100644 → 0
View file @ 4a386c3e
/* 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 avoid multiple threads trying to
* execute it simultaneously
*
* there is, however, a race between us testing the pending flag and
* getting the spinlock, and between the enqueuer setting the pending
* flag and getting the spinlock, so we use a deferral bit to tell us
* if the enqueuer got there first
*/
if (test_bit(SLOW_WORK_PENDING, &work->flags)) {
spin_lock_irq(&slow_work_queue_lock);
if (!test_bit(SLOW_WORK_EXECUTING, &work->flags) &&
test_and_clear_bit(SLOW_WORK_ENQ_DEFERRED, &work->flags))
goto auto_requeue;
spin_unlock_irq(&slow_work_queue_lock);
}
/* sort out the race between module unloading and put_ref() */
slow_work_put_ref(work);
slow_work_done_thread_processing(id, work);
return true;
auto_requeue:
/* we must complete the enqueue operation
* - we transfer our ref on the item back to the appropriate queue
* - don't wake another thread up as we're awake already
*/
slow_work_mark_time(work);
if (test_bit(SLOW_WORK_VERY_SLOW, &work->flags))
list_add_tail(&work->link, &vslow_work_queue);
else
list_add_tail(&work->link, &slow_work_queue);
spin_unlock_irq(&slow_work_queue_lock);
slow_work_clear_thread_processing(id);
return true;
}
/**
* slow_work_sleep_till_thread_needed - Sleep till thread needed by other work
* work: The work item under execution that wants to sleep
* _timeout: Scheduler sleep timeout
*
* Allow a requeueable work item to sleep on a slow-work processor thread until
* that thread is needed to do some other work or the sleep is interrupted by
* some other event.
*
* The caller must set up a wake up event before calling this and must have set
* the appropriate sleep mode (such as TASK_UNINTERRUPTIBLE) and tested its own
* condition before calling this function as no test is made here.
*
* False is returned if there is nothing on the queue; true is returned if the
* work item should be requeued
*/
bool slow_work_sleep_till_thread_needed(struct slow_work *work,
signed long *_timeout)
{
wait_queue_head_t *wfo_wq;
struct list_head *queue;
DEFINE_WAIT(wait);
if (test_bit(SLOW_WORK_VERY_SLOW, &work->flags)) {
wfo_wq = &vslow_work_queue_waits_for_occupation;
queue = &vslow_work_queue;
} else {
wfo_wq = &slow_work_queue_waits_for_occupation;
queue = &slow_work_queue;
}
if (!list_empty(queue))
return true;
add_wait_queue_exclusive(wfo_wq, &wait);
if (list_empty(queue))
*_timeout = schedule_timeout(*_timeout);
finish_wait(wfo_wq, &wait);
return !list_empty(queue);
}
EXPORT_SYMBOL(slow_work_sleep_till_thread_needed);
/**
* slow_work_enqueue - Schedule a slow work item for processing
* @work: The work item to queue
*
* Schedule a slow work item for processing. If the item is already undergoing
* execution, this guarantees not to re-enter the execution routine until the
* first execution finishes.
*
* The item is pinned by this function as it retains a reference to it, managed
* through the item operations. The item is unpinned once it has been
* executed.
*
* An item may hog the thread that is running it for a relatively large amount
* of time, sufficient, for example, to perform several lookup, mkdir, create
* and setxattr operations. It may sleep on I/O and may sleep to obtain locks.
*
* Conversely, if a number of items are awaiting processing, it may take some
* time before any given item is given attention. The number of threads in the
* pool may be increased to deal with demand, but only up to a limit.
*
* If SLOW_WORK_VERY_SLOW is set on the work item, then it will be placed in
* the very slow queue, from which only a portion of the threads will be
* allowed to pick items to execute. This ensures that very slow items won't
* overly block ones that are just ordinarily slow.
*
* Returns 0 if successful, -EAGAIN if not (or -ECANCELED if cancelled work is
* attempted queued)
*/
int slow_work_enqueue(struct slow_work *work)
{
wait_queue_head_t *wfo_wq;
struct list_head *queue;
unsigned long flags;
int ret;
if (test_bit(SLOW_WORK_CANCELLING, &work->flags))
return -ECANCELED;
BUG_ON(slow_work_user_count <= 0);
BUG_ON(!work);
BUG_ON(!work->ops);
/* when honouring an enqueue request, we only promise that we will run
* the work function in the future; we do not promise to run it once
* per enqueue request
*
* we use the PENDING bit to merge together repeat requests without
* having to disable IRQs and take the spinlock, whilst still
* maintaining our promise
*/
if (!test_and_set_bit_lock(SLOW_WORK_PENDING, &work->flags)) {
if (test_bit(SLOW_WORK_VERY_SLOW, &work->flags)) {
wfo_wq = &vslow_work_queue_waits_for_occupation;
queue = &vslow_work_queue;
} else {
wfo_wq = &slow_work_queue_waits_for_occupation;
queue = &slow_work_queue;
}
spin_lock_irqsave(&slow_work_queue_lock, flags);
if (unlikely(test_bit(SLOW_WORK_CANCELLING, &work->flags)))
goto cancelled;
/* we promise that we will not attempt to execute the work
* function in more than one thread simultaneously
*
* this, however, leaves us with a problem if we're asked to
* enqueue the work whilst someone is executing the work
* function as simply queueing the work immediately means that
* another thread may try executing it whilst it is already
* under execution
*
* to deal with this, we set the ENQ_DEFERRED bit instead of
* enqueueing, and the thread currently executing the work
* function will enqueue the work item when the work function
* returns and it has cleared the EXECUTING bit
*/
if (test_bit(SLOW_WORK_EXECUTING, &work->flags)) {
set_bit(SLOW_WORK_ENQ_DEFERRED, &work->flags);
} else {
ret = slow_work_get_ref(work);
if (ret < 0)
goto failed;
slow_work_mark_time(work);
list_add_tail(&work->link, queue);
wake_up(&slow_work_thread_wq);
/* if someone who could be requeued is sleeping on a
* thread, then ask them to yield their thread */
if (work->link.prev == queue)
wake_up(wfo_wq);
}
spin_unlock_irqrestore(&slow_work_queue_lock, flags);
}
return 0;
cancelled:
ret = -ECANCELED;
failed:
spin_unlock_irqrestore(&slow_work_queue_lock, flags);
return ret;
}
EXPORT_SYMBOL(slow_work_enqueue);
static int slow_work_wait(void *word)
{
schedule();
return 0;
}
/**
* slow_work_cancel - Cancel a slow work item
* @work: The work item to cancel
*
* This function will cancel a previously enqueued work item. If we cannot
* cancel the work item, it is guarenteed to have run when this function
* returns.
*/
void slow_work_cancel(struct slow_work *work)
{
bool wait = true, put = false;
set_bit(SLOW_WORK_CANCELLING, &work->flags);
smp_mb();
/* if the work item is a delayed work item with an active timer, we
* need to wait for the timer to finish _before_ getting the spinlock,
* lest we deadlock against the timer routine
*
* the timer routine will leave DELAYED set if it notices the
* CANCELLING flag in time
*/
if (test_bit(SLOW_WORK_DELAYED, &work->flags)) {
struct delayed_slow_work *dwork =
container_of(work, struct delayed_slow_work, work);
del_timer_sync(&dwork->timer);
}
spin_lock_irq(&slow_work_queue_lock);
if (test_bit(SLOW_WORK_DELAYED, &work->flags)) {
/* the timer routine aborted or never happened, so we are left
* holding the timer's reference on the item and should just
* drop the pending flag and wait for any ongoing execution to
* finish */
struct delayed_slow_work *dwork =
container_of(work, struct delayed_slow_work, work);
BUG_ON(timer_pending(&dwork->timer));
BUG_ON(!list_empty(&work->link));
clear_bit(SLOW_WORK_DELAYED, &work->flags);
put = true;
clear_bit(SLOW_WORK_PENDING, &work->flags);
} else if (test_bit(SLOW_WORK_PENDING, &work->flags) &&
!list_empty(&work->link)) {
/* the link in the pending queue holds a reference on the item
* that we will need to release */
list_del_init(&work->link);
wait = false;
put = true;
clear_bit(SLOW_WORK_PENDING, &work->flags);
} else if (test_and_clear_bit(SLOW_WORK_ENQ_DEFERRED, &work->flags)) {
/* the executor is holding our only reference on the item, so
* we merely need to wait for it to finish executing */
clear_bit(SLOW_WORK_PENDING, &work->flags);
}
spin_unlock_irq(&slow_work_queue_lock);
/* the EXECUTING flag is set by the executor whilst the spinlock is set
* and before the item is dequeued - so assuming the above doesn't
* actually dequeue it, simply waiting for the EXECUTING flag to be
* released here should be sufficient */
if (wait)
wait_on_bit(&work->flags, SLOW_WORK_EXECUTING, slow_work_wait,
TASK_UNINTERRUPTIBLE);
clear_bit(SLOW_WORK_CANCELLING, &work->flags);
if (put)
slow_work_put_ref(work);
}
EXPORT_SYMBOL(slow_work_cancel);
/*
* Handle expiry of the delay timer, indicating that a delayed slow work item
* should now be queued if not cancelled
*/
static void delayed_slow_work_timer(unsigned long data)
{
wait_queue_head_t *wfo_wq;
struct list_head *queue;
struct slow_work *work = (struct slow_work *) data;
unsigned long flags;
bool queued = false, put = false, first = false;
if (test_bit(SLOW_WORK_VERY_SLOW, &work->flags)) {
wfo_wq = &vslow_work_queue_waits_for_occupation;
queue = &vslow_work_queue;
} else {
wfo_wq = &slow_work_queue_waits_for_occupation;
queue = &slow_work_queue;
}
spin_lock_irqsave(&slow_work_queue_lock, flags);
if (likely(!test_bit(SLOW_WORK_CANCELLING, &work->flags))) {
clear_bit(SLOW_WORK_DELAYED, &work->flags);
if (test_bit(SLOW_WORK_EXECUTING, &work->flags)) {
/* we discard the reference the timer was holding in
* favour of the one the executor holds */
set_bit(SLOW_WORK_ENQ_DEFERRED, &work->flags);
put = true;
} else {
slow_work_mark_time(work);
list_add_tail(&work->link, queue);
queued = true;
if (work->link.prev == queue)
first = true;
}
}
spin_unlock_irqrestore(&slow_work_queue_lock, flags);
if (put)
slow_work_put_ref(work);
if (first)
wake_up(wfo_wq);
if (queued)
wake_up(&slow_work_thread_wq);
}
/**
* delayed_slow_work_enqueue - Schedule a delayed slow work item for processing
* @dwork: The delayed work item to queue
* @delay: When to start executing the work, in jiffies from now
*
* This is similar to slow_work_enqueue(), but it adds a delay before the work
* is actually queued for processing.
*
* The item can have delayed processing requested on it whilst it is being
* executed. The delay will begin immediately, and if it expires before the
* item finishes executing, the item will be placed back on the queue when it
* has done executing.
*/
int delayed_slow_work_enqueue(struct delayed_slow_work *dwork,
unsigned long delay)
{
struct slow_work *work = &dwork->work;
unsigned long flags;
int ret;
if (delay == 0)
return slow_work_enqueue(&dwork->work);
BUG_ON(slow_work_user_count <= 0);
BUG_ON(!work);
BUG_ON(!work->ops);
if (test_bit(SLOW_WORK_CANCELLING, &work->flags))
return -ECANCELED;
if (!test_and_set_bit_lock(SLOW_WORK_PENDING, &work->flags)) {
spin_lock_irqsave(&slow_work_queue_lock, flags);
if (test_bit(SLOW_WORK_CANCELLING, &work->flags))
goto cancelled;
/* the timer holds a reference whilst it is pending */
ret = slow_work_get_ref(work);
if (ret < 0)
goto cant_get_ref;
if (test_and_set_bit(SLOW_WORK_DELAYED, &work->flags))
BUG();
dwork->timer.expires = jiffies + delay;
dwork->timer.data = (unsigned long) work;
dwork->timer.function = delayed_slow_work_timer;
add_timer(&dwork->timer);
spin_unlock_irqrestore(&slow_work_queue_lock, flags);
}
return 0;
cancelled:
ret = -ECANCELED;
cant_get_ref:
spin_unlock_irqrestore(&slow_work_queue_lock, flags);
return ret;
}
EXPORT_SYMBOL(delayed_slow_work_enqueue);
/*
* Schedule a cull of the thread pool at some time in the near future
*/
static void slow_work_schedule_cull(void)
{
mod_timer(&slow_work_cull_timer,
round_jiffies(jiffies + SLOW_WORK_CULL_TIMEOUT));
}
/*
* Worker thread culling algorithm
*/
static bool slow_work_cull_thread(void)
{
unsigned long flags;
bool do_cull = false;
spin_lock_irqsave(&slow_work_queue_lock, flags);
if (slow_work_cull) {
slow_work_cull = false;
if (list_empty(&slow_work_queue) &&
list_empty(&vslow_work_queue) &&
atomic_read(&slow_work_thread_count) >
slow_work_min_threads) {
slow_work_schedule_cull();
do_cull = true;
}
}
spin_unlock_irqrestore(&slow_work_queue_lock, flags);
return do_cull;
}
/*
* Determine if there is slow work available for dispatch
*/
static inline bool slow_work_available(int vsmax)
{
return !list_empty(&slow_work_queue) ||
(!list_empty(&vslow_work_queue) &&
atomic_read(&vslow_work_executing_count) < vsmax);
}
/*
* Worker thread dispatcher
*/
static int slow_work_thread(void *_data)
{
int vsmax, id;
DEFINE_WAIT(wait);
set_freezable();
set_user_nice(current, -5);
/* allocate ourselves an ID */
spin_lock_irq(&slow_work_queue_lock);
id = find_first_zero_bit(slow_work_ids, SLOW_WORK_THREAD_LIMIT);
BUG_ON(id < 0 || id >= SLOW_WORK_THREAD_LIMIT);
__set_bit(id, slow_work_ids);
slow_work_set_thread_pid(id, current->pid);
spin_unlock_irq(&slow_work_queue_lock);
sprintf(current->comm, "kslowd%03u", id);
for (;;) {
vsmax = vslow_work_proportion;
vsmax *= atomic_read(&slow_work_thread_count);
vsmax /= 100;
prepare_to_wait_exclusive(&slow_work_thread_wq, &wait,
TASK_INTERRUPTIBLE);
if (!freezing(current) &&
!slow_work_threads_should_exit &&
!slow_work_available(vsmax) &&
!slow_work_cull)
schedule();
finish_wait(&slow_work_thread_wq, &wait);
try_to_freeze();
vsmax = vslow_work_proportion;
vsmax *= atomic_read(&slow_work_thread_count);
vsmax /= 100;
if (slow_work_available(vsmax) && slow_work_execute(id)) {
cond_resched();
if (list_empty(&slow_work_queue) &&
list_empty(&vslow_work_queue) &&
atomic_read(&slow_work_thread_count) >
slow_work_min_threads)
slow_work_schedule_cull();
continue;
}
if (slow_work_threads_should_exit)
break;
if (slow_work_cull && slow_work_cull_thread())
break;
}
spin_lock_irq(&slow_work_queue_lock);
slow_work_set_thread_pid(id, 0);
__clear_bit(id, slow_work_ids);
spin_unlock_irq(&slow_work_queue_lock);
if (atomic_dec_and_test(&slow_work_thread_count))
complete_and_exit(&slow_work_last_thread_exited, 0);
return 0;
}
/*
* Handle thread cull timer expiration
*/
static void slow_work_cull_timeout(unsigned long data)
{
slow_work_cull = true;
wake_up(&slow_work_thread_wq);
}
/*
* Start a new slow work thread
*/
static void slow_work_new_thread_execute(struct slow_work *work)
{
struct task_struct *p;
if (slow_work_threads_should_exit)
return;
if (atomic_read(&slow_work_thread_count) >= slow_work_max_threads)
return;
if (!mutex_trylock(&slow_work_user_lock))
return;
slow_work_may_not_start_new_thread = true;
atomic_inc(&slow_work_thread_count);
p = kthread_run(slow_work_thread, NULL, "kslowd");
if (IS_ERR(p)) {
printk(KERN_DEBUG "Slow work thread pool: OOM\n");
if (atomic_dec_and_test(&slow_work_thread_count))
BUG(); /* we're running on a slow work thread... */
mod_timer(&slow_work_oom_timer,
round_jiffies(jiffies + SLOW_WORK_OOM_TIMEOUT));
} else {
/* ratelimit the starting of new threads */
mod_timer(&slow_work_oom_timer, jiffies + 1);
}
mutex_unlock(&slow_work_user_lock);
}
static const struct slow_work_ops slow_work_new_thread_ops = {
.owner = THIS_MODULE,
.execute = slow_work_new_thread_execute,
#ifdef CONFIG_SLOW_WORK_DEBUG
.desc = slow_work_new_thread_desc,
#endif
};
/*
* post-OOM new thread start suppression expiration
*/
static void slow_work_oom_timeout(unsigned long data)
{
slow_work_may_not_start_new_thread = false;
}
#ifdef CONFIG_SYSCTL
/*
* Handle adjustment of the minimum number of threads
*/
static int slow_work_min_threads_sysctl(struct ctl_table *table, int write,
void __user *buffer,
size_t *lenp, loff_t *ppos)
{
int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
int n;
if (ret == 0) {
mutex_lock(&slow_work_user_lock);
if (slow_work_user_count > 0) {
/* see if we need to start or stop threads */
n = atomic_read(&slow_work_thread_count) -
slow_work_min_threads;
if (n < 0 && !slow_work_may_not_start_new_thread)
slow_work_enqueue(&slow_work_new_thread);
else if (n > 0)
slow_work_schedule_cull();
}
mutex_unlock(&slow_work_user_lock);
}
return ret;
}
/*
* Handle adjustment of the maximum number of threads
*/
static int slow_work_max_threads_sysctl(struct ctl_table *table, int write,
void __user *buffer,
size_t *lenp, loff_t *ppos)
{
int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
int n;
if (ret == 0) {
mutex_lock(&slow_work_user_lock);
if (slow_work_user_count > 0) {
/* see if we need to stop threads */
n = slow_work_max_threads -
atomic_read(&slow_work_thread_count);
if (n < 0)
slow_work_schedule_cull();
}
mutex_unlock(&slow_work_user_lock);
}
return ret;
}
#endif /* CONFIG_SYSCTL */
/**
* slow_work_register_user - Register a user of the facility
* @module: The module about to make use of the facility
*
* Register a user of the facility, starting up the initial threads if there
* aren't any other users at this point. This will return 0 if successful, or
* an error if not.
*/
int slow_work_register_user(struct module *module)
{
struct task_struct *p;
int loop;
mutex_lock(&slow_work_user_lock);
if (slow_work_user_count == 0) {
printk(KERN_NOTICE "Slow work thread pool: Starting up\n");
init_completion(&slow_work_last_thread_exited);
slow_work_threads_should_exit = false;
slow_work_init(&slow_work_new_thread,
&slow_work_new_thread_ops);
slow_work_may_not_start_new_thread = false;
slow_work_cull = false;
/* start the minimum number of threads */
for (loop = 0; loop < slow_work_min_threads; loop++) {
atomic_inc(&slow_work_thread_count);
p = kthread_run(slow_work_thread, NULL, "kslowd");
if (IS_ERR(p))
goto error;
}
printk(KERN_NOTICE "Slow work thread pool: Ready\n");
}
slow_work_user_count++;
mutex_unlock(&slow_work_user_lock);
return 0;
error:
if (atomic_dec_and_test(&slow_work_thread_count))
complete(&slow_work_last_thread_exited);
if (loop > 0) {
printk(KERN_ERR "Slow work thread pool:"
" Aborting startup on ENOMEM\n");
slow_work_threads_should_exit = true;
wake_up_all(&slow_work_thread_wq);
wait_for_completion(&slow_work_last_thread_exited);
printk(KERN_ERR "Slow work thread pool: Aborted\n");
}
mutex_unlock(&slow_work_user_lock);
return PTR_ERR(p);
}
EXPORT_SYMBOL(slow_work_register_user);
/*
* wait for all outstanding items from the calling module to complete
* - note that more items may be queued whilst we're waiting
*/
static void slow_work_wait_for_items(struct module *module)
{
#ifdef CONFIG_MODULES
DECLARE_WAITQUEUE(myself, current);
struct slow_work *work;
int loop;
mutex_lock(&slow_work_unreg_sync_lock);
add_wait_queue(&slow_work_unreg_wq, &myself);
for (;;) {
spin_lock_irq(&slow_work_queue_lock);
/* first of all, we wait for the last queued item in each list
* to be processed */
list_for_each_entry_reverse(work, &vslow_work_queue, link) {
if (work->owner == module) {
set_current_state(TASK_UNINTERRUPTIBLE);
slow_work_unreg_work_item = work;
goto do_wait;
}
}
list_for_each_entry_reverse(work, &slow_work_queue, link) {
if (work->owner == module) {
set_current_state(TASK_UNINTERRUPTIBLE);
slow_work_unreg_work_item = work;
goto do_wait;
}
}
/* then we wait for the items being processed to finish */
slow_work_unreg_module = module;
smp_mb();
for (loop = 0; loop < SLOW_WORK_THREAD_LIMIT; loop++) {
if (slow_work_thread_processing[loop] == module)
goto do_wait;
}
spin_unlock_irq(&slow_work_queue_lock);
break; /* okay, we're done */
do_wait:
spin_unlock_irq(&slow_work_queue_lock);
schedule();
slow_work_unreg_work_item = NULL;
slow_work_unreg_module = NULL;
}
remove_wait_queue(&slow_work_unreg_wq, &myself);
mutex_unlock(&slow_work_unreg_sync_lock);
#endif /* CONFIG_MODULES */
}
/**
* slow_work_unregister_user - Unregister a user of the facility
* @module: The module whose items should be cleared
*
* Unregister a user of the facility, killing all the threads if this was the
* last one.
*
* This waits for all the work items belonging to the nominated module to go
* away before proceeding.
*/
void slow_work_unregister_user(struct module *module)
{
/* first of all, wait for all outstanding items from the calling module
* to complete */
if (module)
slow_work_wait_for_items(module);
/* then we can actually go about shutting down the facility if need
* be */
mutex_lock(&slow_work_user_lock);
BUG_ON(slow_work_user_count <= 0);
slow_work_user_count--;
if (slow_work_user_count == 0) {
printk(KERN_NOTICE "Slow work thread pool: Shutting down\n");
slow_work_threads_should_exit = true;
del_timer_sync(&slow_work_cull_timer);
del_timer_sync(&slow_work_oom_timer);
wake_up_all(&slow_work_thread_wq);
wait_for_completion(&slow_work_last_thread_exited);
printk(KERN_NOTICE "Slow work thread pool:"
" Shut down complete\n");
}
mutex_unlock(&slow_work_user_lock);
}
EXPORT_SYMBOL(slow_work_unregister_user);
/*
* Initialise the slow work facility
*/
static int __init init_slow_work(void)
{
unsigned nr_cpus = num_possible_cpus();
if (slow_work_max_threads < nr_cpus)
slow_work_max_threads = nr_cpus;
#ifdef CONFIG_SYSCTL
if (slow_work_max_max_threads < nr_cpus * 2)
slow_work_max_max_threads = nr_cpus * 2;
#endif
#ifdef CONFIG_SLOW_WORK_DEBUG
{
struct dentry *dbdir;
dbdir = debugfs_create_dir("slow_work", NULL);
if (dbdir && !IS_ERR(dbdir))
debugfs_create_file("runqueue", S_IFREG | 0400, dbdir,
NULL, &slow_work_runqueue_fops);
}
#endif
return 0;
}
subsys_initcall(init_slow_work);
kernel/slow-work.h deleted 100644 → 0
View file @ 4a386c3e
/* Slow work private definitions
*
* 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.
*/
#define SLOW_WORK_CULL_TIMEOUT (5 * HZ) /* cull threads 5s after running out of
* things to do */
#define SLOW_WORK_OOM_TIMEOUT (5 * HZ) /* can't start new threads for 5s after
* OOM */
#define SLOW_WORK_THREAD_LIMIT 255 /* abs maximum number of slow-work threads */
/*
* slow-work.c
*/
#ifdef CONFIG_SLOW_WORK_DEBUG
extern struct slow_work *slow_work_execs[];
extern pid_t slow_work_pids[];
extern rwlock_t slow_work_execs_lock;
#endif
extern struct list_head slow_work_queue;
extern struct list_head vslow_work_queue;
extern spinlock_t slow_work_queue_lock;
/*
* slow-work-debugfs.c
*/
#ifdef CONFIG_SLOW_WORK_DEBUG
extern const struct file_operations slow_work_runqueue_fops;
extern void slow_work_new_thread_desc(struct slow_work *, struct seq_file *);
#endif
/*
* Helper functions
*/
static inline void slow_work_set_thread_pid(int id, pid_t pid)
{
#ifdef CONFIG_SLOW_WORK_DEBUG
slow_work_pids[id] = pid;
#endif
}
static inline void slow_work_mark_time(struct slow_work *work)
{
#ifdef CONFIG_SLOW_WORK_DEBUG
work->mark = CURRENT_TIME;
#endif
}
static inline void slow_work_begin_exec(int id, struct slow_work *work)
{
#ifdef CONFIG_SLOW_WORK_DEBUG
slow_work_execs[id] = work;
#endif
}
static inline void slow_work_end_exec(int id, struct slow_work *work)
{
#ifdef CONFIG_SLOW_WORK_DEBUG
write_lock(&slow_work_execs_lock);
slow_work_execs[id] = NULL;
write_unlock(&slow_work_execs_lock);
#endif
}
kernel/sysctl.c
View file @ 3b7433b8
......@@ -50,7 +50,6 @@
#include <linux/acpi.h>
#include <linux/reboot.h>
#include <linux/ftrace.h>
#include <linux/slow-work.h>
#include <linux/perf_event.h>
#include <linux/kprobes.h>
#include <linux/pipe_fs_i.h>
......@@ -917,13 +916,6 @@ static struct ctl_table kern_table[] = {
.proc_handler = proc_dointvec,
},
#endif
#ifdef CONFIG_SLOW_WORK
{
.procname = "slow-work",
.mode = 0555,
.child = slow_work_sysctls,
},
#endif
#ifdef CONFIG_PERF_EVENTS
{
.procname = "perf_event_paranoid",
......
kernel/trace/Kconfig
View file @ 3b7433b8
......@@ -323,17 +323,6 @@ config STACK_TRACER
Say N if unsure.
config WORKQUEUE_TRACER
bool "Trace workqueues"
select GENERIC_TRACER
help
The workqueue tracer provides some statistical information
about each cpu workqueue thread such as the number of the
works inserted and executed since their creation. It can help
to evaluate the amount of work each of them has to perform.
For example it can help a developer to decide whether he should
choose a per-cpu workqueue instead of a singlethreaded one.
config BLK_DEV_IO_TRACE
bool "Support for tracing block IO actions"
depends on SYSFS
......
kernel/workqueue.c
View file @ 3b7433b8
This source diff could not be displayed because it is too large. You can view the blob instead.
kernel/workqueue_sched.h
View file @ 3b7433b8
......@@ -4,13 +4,6 @@
* Scheduler hooks for concurrency managed workqueue. Only to be
* included from sched.c and workqueue.c.
*/
static inline void wq_worker_waking_up(struct task_struct *task,
unsigned int cpu)
{
}
static inline struct task_struct *wq_worker_sleeping(struct task_struct *task,
unsigned int cpu)
{
return NULL;
}
void wq_worker_waking_up(struct task_struct *task, unsigned int cpu);
struct task_struct *wq_worker_sleeping(struct task_struct *task,
unsigned int cpu);
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