10148 Commits

Author SHA1 Message Date
Frederic Weisbecker
eb7beb5c09 tracing: Remove special traces
Special traces type was only used by sysprof. Lets remove it now
that sysprof ftrace plugin has been dropped.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Soeren Sandmann <sandmann@daimi.au.dk>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
2010-07-20 14:31:07 +02:00
Frederic Weisbecker
f376bf5ffb tracing: Remove sysprof ftrace plugin
The sysprof ftrace plugin doesn't seem to be seriously used
somewhere. There is a branch in the sysprof tree that makes
an interface to it, but the real sysprof tool uses either its
own module or perf events.

Drop the sysprof ftrace plugin then, as it's mostly useless.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Soeren Sandmann <sandmann@daimi.au.dk>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
2010-07-20 14:29:46 +02:00
Tejun Heo
931ac77ef6 workqueue: fix build problem on !CONFIG_SMP
Commit f3421797 (workqueue: implement unbound workqueue) incorrectly
tested CONFIG_SMP as part of a C expression in alloc/free_cwqs().  As
CONFIG_SMP is not defined in UP, this breaks build.  Fix it by using

Found during linux-next build test.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
2010-07-20 11:15:14 +02:00
Catalin Marinas
9078370c0d kmemleak: Add support for NO_BOOTMEM configurations
With commits 08677214 and 59be5a8e, alloc_bootmem()/free_bootmem() and
friends use the early_res functions for memory management when
NO_BOOTMEM is enabled. This patch adds the kmemleak calls in the
corresponding code paths for bootmem allocations.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: stable@kernel.org
2010-07-19 11:54:15 +01:00
Pavel Machek
a2531293db update email address
pavel@suse.cz no longer works, replace it with working address.

Signed-off-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-07-19 10:56:54 +02:00
Dan Kruchinin
5e017dc3f8 padata: Added sysfs primitives to padata subsystem
Added sysfs primitives to padata subsystem. Now API user may
embedded kobject each padata instance contains into any sysfs
hierarchy. For now padata sysfs interface provides only
two objects:
    serial_cpumask   [RW] - cpumask for serial workers
    parallel_cpumask [RW] - cpumask for parallel workers

Signed-off-by: Dan Kruchinin <dkruchinin@acm.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-19 13:50:19 +08:00
Dan Kruchinin
e15bacbebb padata: Make two separate cpumasks
The aim of this patch is to make two separate cpumasks
for padata parallel and serial workers respectively.
It allows user to make more thin and sophisticated configurations
of padata framework. For example user may bind parallel and serial workers to non-intersecting
CPU groups to gain better performance. Also each padata instance has notifiers chain for its
cpumasks now. If either parallel or serial or both masks were changed all
interested subsystems will get notification about that. It's especially useful
if padata user uses algorithm for callback CPU selection according to serial cpumask.

Signed-off-by: Dan Kruchinin <dkruchinin@acm.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-19 13:50:19 +08:00
Rafael J. Wysocki
ce4410116c PM / Suspend: Fix ordering of calls in suspend error paths
The ACPI suspend code calls suspend_nvs_free() at a wrong place,
which may lead to a memory leak if there's an error executing
acpi_pm_prepare(), because acpi_pm_finish() will not be called in
that case.  However, the root cause of this problem is the
apparently confusing ordering of calls in suspend error paths that
needs to be fixed.

In addition to that, fix a typo in a label name in suspend.c.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Len Brown <len.brown@intel.com>
2010-07-19 02:00:35 +02:00
Rafael J. Wysocki
d074ee023f PM / Hibernate: Fix snapshot error code path
There is an inconsistency between hibernation_platform_enter()
and hibernation_snapshot(), because the latter calls
hibernation_ops->end() after failing hibernation_ops->begin(), while
the former doesn't do that.  Make hibernation_snapshot() behave in
the same way as hibernation_platform_enter() in that respect.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Len Brown <len.brown@intel.com>
2010-07-19 02:00:35 +02:00
Rafael J. Wysocki
f6f71f1875 PM / Hibernate: Fix hibernation_platform_enter()
The hibernation_platform_enter() function calls dpm_suspend_noirq()
instead of dpm_resume_noirq() by mistake.  Fix this.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Len Brown <len.brown@intel.com>
2010-07-19 02:00:35 +02:00
James Bottomley
82f682514a pm_qos: Get rid of the allocation in pm_qos_add_request()
All current users of pm_qos_add_request() have the ability to supply
the memory required by the pm_qos routines, so make them do this and
eliminate the kmalloc() with pm_qos_add_request().  This has the
double benefit of making the call never fail and allowing it to be
called from atomic context.

Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: mark gross <markgross@thegnar.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-07-19 02:00:34 +02:00
James Bottomley
5f279845f9 pm_qos: Reimplement using plists
A lot of the pm_qos extremal value handling is really duplicating what a
priority ordered list does, just in a less efficient fashion.  Simply
redoing the implementation in terms of a plist gets rid of a lot of this
junk (although there are several other strange things that could do with
tidying up, like pm_qos_request_list has to carry the pm_qos_class with
every node, simply because it doesn't get passed in to
pm_qos_update_request even though every caller knows full well what
parameter it's updating).

I think this redo is a win independent of android, so we should do
something like this now.

Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: mark gross <markgross@thegnar.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-07-19 02:00:18 +02:00
Rafael J. Wysocki
c125e96f04 PM: Make it possible to avoid races between wakeup and system sleep
One of the arguments during the suspend blockers discussion was that
the mainline kernel didn't contain any mechanisms making it possible
to avoid races between wakeup and system suspend.

Generally, there are two problems in that area.  First, if a wakeup
event occurs exactly when /sys/power/state is being written to, it
may be delivered to user space right before the freezer kicks in, so
the user space consumer of the event may not be able to process it
before the system is suspended.  Second, if a wakeup event occurs
after user space has been frozen, it is not generally guaranteed that
the ongoing transition of the system into a sleep state will be
aborted.

To address these issues introduce a new global sysfs attribute,
/sys/power/wakeup_count, associated with a running counter of wakeup
events and three helper functions, pm_stay_awake(), pm_relax(), and
pm_wakeup_event(), that may be used by kernel subsystems to control
the behavior of this attribute and to request the PM core to abort
system transitions into a sleep state already in progress.

The /sys/power/wakeup_count file may be read from or written to by
user space.  Reads will always succeed (unless interrupted by a
signal) and return the current value of the wakeup events counter.
Writes, however, will only succeed if the written number is equal to
the current value of the wakeup events counter.  If a write is
successful, it will cause the kernel to save the current value of the
wakeup events counter and to abort the subsequent system transition
into a sleep state if any wakeup events are reported after the write
has returned.

[The assumption is that before writing to /sys/power/state user space
will first read from /sys/power/wakeup_count.  Next, user space
consumers of wakeup events will have a chance to acknowledge or
veto the upcoming system transition to a sleep state.  Finally, if
the transition is allowed to proceed, /sys/power/wakeup_count will
be written to and if that succeeds, /sys/power/state will be written
to as well.  Still, if any wakeup events are reported to the PM core
by kernel subsystems after that point, the transition will be
aborted.]

Additionally, put a wakeup events counter into struct dev_pm_info and
make these per-device wakeup event counters available via sysfs,
so that it's possible to check the activity of various wakeup event
sources within the kernel.

To illustrate how subsystems can use pm_wakeup_event(), make the
low-level PCI runtime PM wakeup-handling code use it.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: markgross <markgross@thegnar.org>
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
2010-07-19 01:58:48 +02:00
Cesar Eduardo Barros
9013367339 PM / Hibernate: Fix typos in comments in kernel/power/swap.c
There are a few typos in kernel/power/swap.c.  Fix them.

Signed-off-by: Cesar Eduardo Barros <cesarb@cesarb.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-07-19 01:58:47 +02:00
Pekka Enberg
68c38fc3cb sched: No need for bootmem special cases
As of commit dcce284 ("mm: Extend gfp masking to the page
allocator") and commit 7e85ee0 ("slab,slub: don't enable
interrupts during early boot"), the slab allocator makes
sure we don't attempt to sleep during boot.

Therefore, remove bootmem special cases from the scheduler
and use plain GFP_KERNEL instead.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1279225102-2572-1-git-send-email-penberg@cs.helsinki.fi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-07-17 12:06:22 +02:00
Peter Zijlstra
396e894d28 sched: Revert nohz_ratelimit() for now
Norbert reported that nohz_ratelimit() causes his laptop to burn about
4W (40%) extra. For now back out the change and see if we can adjust
the power management code to make better decisions.

Reported-by: Norbert Preining <preining@logic.at>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Mike Galbraith <efault@gmx.de>
Cc: Arjan van de Ven <arjan@infradead.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-07-17 12:05:44 +02:00
Peter Zijlstra
bbc8cb5bae sched: Reduce update_group_power() calls
Currently we update cpu_power() too often, update_group_power() only
updates the local group's cpu_power but it gets called for all groups.

Furthermore, CPU_NEWLY_IDLE invocations will result in all cpus
calling it, even though a slow update of cpu_power is sufficient.

Therefore move the update under 'idle != CPU_NEWLY_IDLE &&
local_group' to reduce superfluous invocations.

Reported-by: Venkatesh Pallipadi <venki@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1278612989.1900.176.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-07-17 12:05:14 +02:00
Suresh Siddha
5343bdb8fd sched: Update rq->clock for nohz balanced cpus
Suresh spotted that we don't update the rq->clock in the nohz
load-balancer path.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1278626014.2834.74.camel@sbs-t61.sc.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-07-17 12:02:08 +02:00
Jiri Slaby
c022a0acad rlimits: implement prlimit64 syscall
This patch adds the code to support the sys_prlimit64 syscall which
modifies-and-returns the rlim values of a selected process atomically.
The first parameter, pid, being 0 means current process.

Unlike the current implementation, it is a generic interface,
architecture indepentent so that we needn't handle compat stuff
anymore. In the future, after glibc start to use this we can deprecate
sys_setrlimit and sys_getrlimit in favor to clean up the code finally.

It also adds a possibility of changing limits of other processes. We
check the user's permissions to do that and if it succeeds, the new
limits are propagated online. This is good for large scale
applications such as SAP or databases where administrators need to
change limits time by time (e.g. on crashes increase core size). And
it is unacceptable to restart the service.

For safety, all rlim users now either use accessors or doesn't need
them due to
- locking
- the fact a process was just forked and nobody else knows about it
  yet (and nobody can't thus read/write limits)
hence it is safe to modify limits now.

The limitation is that we currently stay at ulong internal
representation. So the rlim64_is_infinity check is used where value is
compared against ULONG_MAX on 32-bit which is the maximum value there.

And since internally the limits are held in struct rlimit, converters
which are used before and after do_prlimit call in sys_prlimit64 are
introduced.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2010-07-16 09:48:48 +02:00
Jiri Slaby
b95183453a rlimits: switch more rlimit syscalls to do_prlimit
After we added more generic do_prlimit, switch sys_getrlimit to that.
Also switch compat handling, so we can get rid of ugly __user casts
and avoid setting process' address limit to kernel data and back.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2010-07-16 09:48:48 +02:00
Jiri Slaby
5b41535aac rlimits: redo do_setrlimit to more generic do_prlimit
It now allows also reading of limits. I.e. all read and writes will
later use this function.

It takes two parameters, new and old limits which can be both NULL.
If new is non-NULL, the value in it is set to rlimits.
If old is non-NULL, current rlimits are stored there.
If both are non-NULL, old are stored prior to setting the new ones,
atomically.
(Similar to sigaction.)

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2010-07-16 09:48:48 +02:00
Jiri Slaby
86f162f4c7 rlimits: do security check under task_lock
Do security_task_setrlimit under task_lock. Other tasks may change
limits under our hands while we are checking limits inside the
function. From now on, they can't.

Note that all the security work is done under a spinlock here now.
Security hooks count with that, they are called from interrupt context
(like security_task_kill) and with spinlocks already held (e.g.
capable->security_capable).

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: James Morris <jmorris@namei.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
2010-07-16 09:48:47 +02:00
Jiri Slaby
1c1e618ddd rlimits: allow setrlimit to non-current tasks
Add locking to allow setrlimit accept task parameter other than
current.

Namely, lock tasklist_lock for read and check whether the task
structure has sighand non-null. Do all the signal processing under
that lock still held.

There are some points:
1) security_task_setrlimit is now called with that lock held. This is
   not new, many security_* functions are called with this lock held
   already so it doesn't harm (all this security_* stuff does almost
   the same).
2) task->sighand->siglock (in update_rlimit_cpu) is nested in
   tasklist_lock. This dependence is already existing.
3) tsk->alloc_lock is nested in tasklist_lock. This is OK too, already
   existing dependence.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
2010-07-16 09:48:47 +02:00
Jiri Slaby
7855c35da7 rlimits: split sys_setrlimit
Create do_setrlimit from sys_setrlimit and declare do_setrlimit
in the resource header. This is the first phase to have generic
do_prlimit which allows to be called from read, write and compat
rlimits code.

The new do_setrlimit also accepts a task pointer to change the limits
of. Currently, it cannot be other than current, but this will change
with locking later.

Also pass tsk->group_leader to security_task_setrlimit to check
whether current is allowed to change rlimits of the process and not
its arbitrary thread because it makes more sense given that rlimit are
per process and not per-thread.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2010-07-16 09:48:46 +02:00
Oleg Nesterov
2fb9d2689a rlimits: make sure ->rlim_max never grows in sys_setrlimit
Mostly preparation for Jiri's changes, but probably makes sense anyway.

sys_setrlimit() checks new_rlim.rlim_max <= old_rlim->rlim_max, but when
it takes task_lock() old_rlim->rlim_max can be already lowered. Move this
check under task_lock().

Currently this is not important, we can only race with our sub-thread,
this means the application is stupid. But when we change the code to allow
the update of !current task's limits, it becomes important to make sure
->rlim_max can be lowered "reliably" even if we race with the application
doing sys_setrlimit().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
2010-07-16 09:48:46 +02:00
Jiri Slaby
5ab46b345e rlimits: add task_struct to update_rlimit_cpu
Add task_struct as a parameter to update_rlimit_cpu to be able to set
rlimit_cpu of different task than current.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Acked-by: James Morris <jmorris@namei.org>
2010-07-16 09:48:45 +02:00
Jiri Slaby
8fd00b4d70 rlimits: security, add task_struct to setrlimit
Add task_struct to task_setrlimit of security_operations to be able to set
rlimit of task other than current.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Acked-by: Eric Paris <eparis@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
2010-07-16 09:48:45 +02:00
Frederic Weisbecker
5d550467b9 tracing: Remove ksym tracer
The ksym (breakpoint) ftrace plugin has been superseded by perf
tools that are much more poweful to use the cpu breakpoints.
This tracer doesn't bring more feature. It has been deprecated
for a while now, lets remove it.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Prasad <prasad@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
2010-07-15 23:59:33 +02:00
Steffen Klassert
5f1a8c1bc7 padata: simplify serialization mechanism
We count the number of processed objects on a percpu basis,
so we need to go through all the percpu reorder queues to calculate
the sequence number of the next object that needs serialization.
This patch changes this to count the number of processed objects
global. So we can calculate the sequence number and the percpu
reorder queue of the next object that needs serialization without
searching through the percpu reorder queues. This avoids some
accesses to memory of foreign cpus.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-14 20:29:30 +08:00
Steffen Klassert
83f619f3c8 padata: make padata_do_parallel to return zero on success
To return -EINPROGRESS on success in padata_do_parallel was
considered to be odd. This patch changes this to return zero
on success. Also the only user of padata, pcrypt is adapted to
convert a return of zero to -EINPROGRESS within the crypto layer.
This also removes the pcrypt fallback if padata_do_parallel
was called on a not running padata instance as we can't handle it
anymore. This fallback was unused, so it's save to remove it.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-14 20:29:29 +08:00
Steffen Klassert
33e5445068 padata: Handle empty padata cpumasks
This patch fixes a bug when the padata cpumask does not
intersect with the active cpumask. In this case we get a
division by zero in padata_alloc_pd and we end up with a
useless padata instance. Padata can end up with an empty
cpumask for two reasons:

1. A user removed the last cpu that belongs to the padata
cpumask and the active cpumask.

2. The last cpu that belongs to the padata cpumask and the
active cpumask goes offline.

We introduce a function padata_validate_cpumask to check if the padata
cpumask does intersect with the active cpumask. If the cpumasks do not
intersect we mark the instance as invalid, so it can't be used. We do not
allocate the cpumask dependend recources in this case. This fixes the
division by zero and keeps the padate instance in a consistent state.

It's not possible to trigger this bug by now because the only padata user,
pcrypt uses always the possible cpumask.

Reported-by: Dan Kruchinin <dkruchinin@acm.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-14 20:29:29 +08:00
Steffen Klassert
ee83655512 padata: Block until the instance is unused on stop
This patch makes padata_stop to block until the padata
instance is unused. Also we split padata_stop to a locked
and a unlocked version. This is in preparation to be able
to change the cpumask after a call to patata stop.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-14 20:29:29 +08:00
Steffen Klassert
4c87917029 padata: Check for valid padata instance on start
This patch introduces the PADATA_INVALID flag which is
checked on padata start. This will be used to mark a padata
instance as invalid, if the padata cpumask does not intersect
with the active cpumask. we change padata_start to return an
error if the PADATA_INVALID is set. Also we adapt the only
padata user, pcrypt to this change.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-07-14 20:29:28 +08:00
Tejun Heo
9f9c23644b workqueue: fix locking in retry path of maybe_create_worker()
maybe_create_worker() mismanaged locking when worker creation fails
and it has to retry.  Fix locking and simplify lock manipulation.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Yong Zhang <yong.zhang@windriver.com>
2010-07-14 11:31:20 +02:00
Tejun Heo
083b804c4d async: use workqueue for worker pool
Replace private worker pool with system_unbound_wq.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Arjan van de Ven <arjan@infradead.org>
2010-07-14 11:29:46 +02:00
Uwe Kleine-König
698f93159a fix comment/printk typos concerning "already"
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-07-11 21:45:40 +02:00
Arnd Bergmann
5e3d20a68f init: Remove the BKL from startup code
I have shown by code review that no driver takes
the BKL at init time any more, so whatever the
init code was locking against is no longer there
and it is now safe to remove the BKL there.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Steven Rostedt <rostedt@goodmis>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-07-09 15:40:32 +02:00
Benjamin Herrenschmidt
5f07aa7524 Merge commit 'paulus-perf/master' into next 2010-07-09 11:25:48 +10:00
Kulikov Vasiliy
eb703f9819 kernel/watchdog: Initialize 'result'
Variable on the stack is not initialized to zero, do it
explicitly.

This bug was found by a compiler warning:

 kernel/watchdog.c:463: warning: 'result' may be used uninitialized in this function

Signed-off-by: Kulikov Vasiliy <segooon@gmail.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1278316854-28442-1-git-send-email-segooon@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-07-07 08:46:42 +02:00
Ingo Molnar
8bd0e1be25 Merge branch 'perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux-2.6 into perf/core 2010-07-06 09:00:32 +02:00
Masami Hiramatsu
e09c8614b3 tracing/kprobes: Support "string" type
Support string type tracing and printing in kprobe-tracer.

This allows user to trace string data in kernel including __user data. Note
that sometimes __user data may not be accessed if it is paged-out (sorry, but
kprobes operation should be done in atomic, we can not wait for page-in).

Commiter note: Fixed up conflicts with b7e2ece.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100519195724.2885.18788.stgit@localhost6.localdomain6>
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-07-05 15:54:45 -03:00
Ingo Molnar
08f8ba0799 Merge commit 'v2.6.35-rc4' into perf/core
Merge reason: Pick up the latest perf fixes

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-07-05 08:30:58 +02:00
Yehuda Sadeh
ff49d74ad3 module: initialize module dynamic debug later
We should initialize the module dynamic debug datastructures
only after determining that the module is not loaded yet. This
fixes a bug that introduced in 2.6.35-rc2, where when a trying
to load a module twice, we also load it's dynamic printing data
twice which causes all sorts of nasty issues. Also handle
the dynamic debug cleanup later on failure.

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (removed a #ifdef)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-07-04 20:17:22 -07:00
Linus Torvalds
123f94f22e Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: Cure nr_iowait_cpu() users
  init: Fix comment
  init, sched: Fix race between init and kthreadd
2010-07-02 09:52:58 -07:00
Tejun Heo
c7fc77f78f workqueue: remove WQ_SINGLE_CPU and use WQ_UNBOUND instead
WQ_SINGLE_CPU combined with @max_active of 1 is used to achieve full
ordering among works queued to a workqueue.  The same can be achieved
using WQ_UNBOUND as unbound workqueues always use the gcwq for
WORK_CPU_UNBOUND.  As @max_active is always one and benefits from cpu
locality isn't accessible anyway, serving them with unbound workqueues
should be fine.

Drop WQ_SINGLE_CPU support and use WQ_UNBOUND instead.  Note that most
single thread workqueue users will be converted to use multithread or
non-reentrant instead and only the ones which require strict ordering
will keep using WQ_UNBOUND + @max_active of 1.

Signed-off-by: Tejun Heo <tj@kernel.org>
2010-07-02 11:00:08 +02:00
Tejun Heo
f34217977d workqueue: implement unbound workqueue
This patch implements unbound workqueue which can be specified with
WQ_UNBOUND flag on creation.  An unbound workqueue has the following
properties.

* It uses a dedicated gcwq with a pseudo CPU number WORK_CPU_UNBOUND.
  This gcwq is always online and disassociated.

* Workers are not bound to any CPU and not concurrency managed.  Works
  are dispatched to workers as soon as possible and the only applied
  limitation is @max_active.  IOW, all unbound workqeueues are
  implicitly high priority.

Unbound workqueues can be used as simple execution context provider.
Contexts unbound to any cpu are served as soon as possible.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: David Howells <dhowells@redhat.com>
2010-07-02 11:00:02 +02:00
Tejun Heo
bdbc5dd7de workqueue: prepare for WQ_UNBOUND implementation
In preparation of WQ_UNBOUND addition, make the following changes.

* Add WORK_CPU_* constants for pseudo cpu id numbers used (currently
  only WORK_CPU_NONE) and use them instead of NR_CPUS.  This is to
  allow another pseudo cpu id for unbound cpu.

* Reorder WQ_* flags.

* Make workqueue_struct->cpu_wq a union which contains a percpu
  pointer, regular pointer and an unsigned long value and use
  kzalloc/kfree() in UP allocation path.  This will be used to
  implement unbound workqueues which will use only one cwq on SMPs.

* Move alloc_cwqs() allocation after initialization of wq fields, so
  that alloc_cwqs() has access to wq->flags.

* Trivial relocation of wq local variables in freeze functions.

These changes don't cause any functional change.

Signed-off-by: Tejun Heo <tj@kernel.org>
2010-07-02 10:59:57 +02:00
Tejun Heo
d313dd85ad workqueue: fix worker management invocation without pending works
When there's no pending work to do, worker_thread() goes back to sleep
after waking up without checking whether worker management is
necessary.  This means that idle worker exit requests can be ignored
if the gcwq stays empty.

Fix it by making worker_thread() always check whether worker
management is necessary before going to sleep.

Signed-off-by: Tejun Heo <tj@kernel.org>
2010-07-02 10:03:51 +02:00
Tejun Heo
a1e453d279 workqueue: fix incorrect cpu number BUG_ON() in get_work_gcwq()
get_work_gcwq() was incorrectly triggering BUG_ON() if cpu number is
equal to or higher than num_possible_cpus() instead of nr_cpu_ids.
Fix it.

Signed-off-by: Tejun Heo <tj@kernel.org>
2010-07-02 10:03:51 +02:00
Tejun Heo
4ce48b37bf workqueue: fix race condition in flush_workqueue()
When one flusher is cascading to the next flusher, it first sets
wq->first_flusher to the next one and sets up the next flush cycle.
If there's nothing to do for the next cycle, it clears
wq->flush_flusher and proceeds to the one after that.

If the woken up flusher checks wq->first_flusher before it gets
cleared, it will incorrectly assume the role of the first flusher,
which triggers BUG_ON() sanity check.

Fix it by checking wq->first_flusher again after grabbing the mutex.

Signed-off-by: Tejun Heo <tj@kernel.org>
2010-07-02 10:03:51 +02:00