Commit Graph

12424 Commits

Author SHA1 Message Date
Andrew Bresticker
c1e2ee2dc4 memcg: replace ss->id_lock with a rwlock
While back-porting Johannes Weiner's patch "mm: memcg-aware global
reclaim" for an internal effort, we noticed a significant performance
regression during page-reclaim heavy workloads due to high contention of
the ss->id_lock.  This lock protects idr map, and serializes calls to
idr_get_next() in css_get_next() (which is used during the memcg hierarchy
walk).

Since idr_get_next() is just doing a look up, we need only serialize it
with respect to idr_remove()/idr_get_new().  By making the ss->id_lock a
rwlock, contention is greatly reduced and performance improves.

Tested: cat a 256m file from a ramdisk in a 128m container 50 times on
each core (one file + container per core) in parallel on a NUMA machine.
Result is the time for the test to complete in 1 of the containers.
Both kernels included Johannes' memcg-aware global reclaim patches.

Before rwlock patch: 1710.778s
After rwlock patch: 152.227s

Signed-off-by: Andrew Bresticker <abrestic@google.com>
Cc: Paul Menage <menage@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Ying Han <yinghan@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-02 16:07:03 -07:00
Lucas De Marchi
f1ecf06854 sysctl: add support for poll()
Adding support for poll() in sysctl fs allows userspace to receive
notifications of changes in sysctl entries.  This adds a infrastructure to
allow files in sysctl fs to be pollable and implements it for hostname and
domainname.

[akpm@linux-foundation.org: s/declare/define/ for definitions]
Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Cc: Greg KH <gregkh@suse.de>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-02 16:07:02 -07:00
David Rientjes
89e8a244b9 cpusets: avoid looping when storing to mems_allowed if one node remains set
{get,put}_mems_allowed() exist so that general kernel code may locklessly
access a task's set of allowable nodes without having the chance that a
concurrent write will cause the nodemask to be empty on configurations
where MAX_NUMNODES > BITS_PER_LONG.

This could incur a significant delay, however, especially in low memory
conditions because the page allocator is blocking and reclaim requires
get_mems_allowed() itself.  It is not atypical to see writes to
cpuset.mems take over 2 seconds to complete, for example.  In low memory
conditions, this is problematic because it's one of the most imporant
times to change cpuset.mems in the first place!

The only way a task's set of allowable nodes may change is through cpusets
by writing to cpuset.mems and when attaching a task to a generic code is
not reading the nodemask with get_mems_allowed() at the same time, and
then clearing all the old nodes.  This prevents the possibility that a
reader will see an empty nodemask at the same time the writer is storing a
new nodemask.

If at least one node remains unchanged, though, it's possible to simply
set all new nodes and then clear all the old nodes.  Changing a task's
nodemask is protected by cgroup_mutex so it's guaranteed that two threads
are not changing the same task's nodemask at the same time, so the
nodemask is guaranteed to be stored before another thread changes it and
determines whether a node remains set or not.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Paul Menage <paul@paulmenage.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-02 16:07:00 -07:00
Ben Blum
77ceab8ea5 cgroups: don't attach task to subsystem if migration failed
If a task has exited to the point it has called cgroup_exit() already,
then we can't migrate it to another cgroup anymore.

This can happen when we are attaching a task to a new cgroup between the
call to ->can_attach_task() on subsystems and the migration that is
eventually tried in cgroup_task_migrate().

In this case cgroup_task_migrate() returns -ESRCH and we don't want to
attach the task to the subsystems because the attachment to the new cgroup
itself failed.

Fix this by only calling ->attach_task() on the subsystems if the cgroup
migration succeeded.

Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Ben Blum <bblum@andrew.cmu.edu>
Acked-by: Paul Menage <paul@paulmenage.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-02 16:06:59 -07:00
Ben Blum
33ef6b6984 cgroups: more safe tasklist locking in cgroup_attach_proc
Fix unstable tasklist locking in cgroup_attach_proc.

According to this thread - https://lkml.org/lkml/2011/7/27/243 - RCU is
not sufficient to guarantee the tasklist is stable w.r.t.  de_thread and
exit.  Taking tasklist_lock for reading, instead of rcu_read_lock, ensures
proper exclusion.

Signed-off-by: Ben Blum <bblum@andrew.cmu.edu>
Acked-by: Paul Menage <paul@paulmenage.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-02 16:06:59 -07:00
Li Zefan
ed0449af53 tracing: Restore system filter behavior
Though not all events have field 'prev_pid', it was allowed to do this:

  # echo 'prev_pid == 100' > events/sched/filter

but commit 75b8e98263 (tracing/filter: Swap
entire filter of events) broke it without any reason.

Link: http://lkml.kernel.org/r/4EAF46CF.8040408@cn.fujitsu.com

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-11-02 13:56:25 -04:00
Linus Torvalds
367069f16e Merge branch 'next/dt' of git://git.linaro.org/people/arnd/arm-soc
* 'next/dt' of git://git.linaro.org/people/arnd/arm-soc:
  ARM: gic: use module.h instead of export.h
  ARM: gic: fix irq_alloc_descs handling for sparse irq
  ARM: gic: add OF based initialization
  ARM: gic: add irq_domain support
  irq: support domains with non-zero hwirq base
  of/irq: introduce of_irq_init
  ARM: at91: add at91sam9g20 and Calao USB A9G20 DT support
  ARM: at91: dt: at91sam9g45 family and board device tree files
  arm/mx5: add device tree support for imx51 babbage
  arm/mx5: add device tree support for imx53 boards
  ARM: msm: Add devicetree support for msm8660-surf
  msm_serial: Add devicetree support
  msm_serial: Use relative resources for iomem

Fix up conflicts in arch/arm/mach-at91/{at91sam9260.c,at91sam9g45.c}
2011-11-01 21:02:35 -07:00
Linus Torvalds
094803e0aa Merge branch 'akpm' (Andrew's incoming)
Quoth Andrew:

 - Most of MM.  Still waiting for the poweroc guys to get off their
   butts and review some threaded hugepages patches.

 - alpha

 - vfs bits

 - drivers/misc

 - a few core kerenl tweaks

 - printk() features

 - MAINTAINERS updates

 - backlight merge

 - leds merge

 - various lib/ updates

 - checkpatch updates

* akpm: (127 commits)
  epoll: fix spurious lockdep warnings
  checkpatch: add a --strict check for utf-8 in commit logs
  kernel.h/checkpatch: mark strict_strto<foo> and simple_strto<foo> as obsolete
  llist-return-whether-list-is-empty-before-adding-in-llist_add-fix
  wireless: at76c50x: follow rename pack_hex_byte to hex_byte_pack
  fat: follow rename pack_hex_byte() to hex_byte_pack()
  security: follow rename pack_hex_byte() to hex_byte_pack()
  kgdb: follow rename pack_hex_byte() to hex_byte_pack()
  lib: rename pack_hex_byte() to hex_byte_pack()
  lib/string.c: fix strim() semantics for strings that have only blanks
  lib/idr.c: fix comment for ida_get_new_above()
  lib/percpu_counter.c: enclose hotplug only variables in hotplug ifdef
  lib/bitmap.c: quiet sparse noise about address space
  lib/spinlock_debug.c: print owner on spinlock lockup
  lib/kstrtox: common code between kstrto*() and simple_strto*() functions
  drivers/leds/leds-lp5521.c: check if reset is successful
  leds: turn the blink_timer off before starting to blink
  leds: save the delay values after a successful call to blink_set()
  drivers/leds/leds-gpio.c: use gpio_get_value_cansleep() when initializing
  drivers/leds/leds-lm3530.c: add __devexit_p where needed
  ...
2011-10-31 17:46:07 -07:00
Andy Shevchenko
50e1499f46 kgdb: follow rename pack_hex_byte() to hex_byte_pack()
There is no functional change.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:56 -07:00
William Douglas
ae29bc92da printk: remove bounds checking for log_prefix
Currently log_prefix is testing that the first character of the log level
and facility is less than '0' and greater than '9' (which is always
false).

Since the code being updated works because strtoul bombs out (endp isn't
updated) and 0 is returned anyway just remove the check and don't change
the behavior of the function.

Signed-off-by: William Douglas <william.douglas@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:53 -07:00
William Douglas
48e41899e4 printk: fix bounds checking for log_prefix
Currently log_prefix is testing that the first character of the log level
and facility is less than '0' and greater than '9' (which is always
false).  It should be testing to see if the character less than '0' or
greater than '9' instead.  This patch makes that change.

The code being changed worked because strtoul bombs out (endp isn't
updated) and 0 is returned anyway.

Signed-off-by: William Douglas <william.douglas@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:53 -07:00
Yanmin Zhang
134620f7a8 printk: add console_suspend module parameter
We are enabling some power features on medfield.  To test suspend-2-RAM
conveniently, we need turn on/off console_suspend_enabled frequently.

Add a module parameter, so users could change it by:
/sys/module/printk/parameters/console_suspend

Signed-off-by: Yanmin Zhang <yanmin_zhang@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:53 -07:00
Yanmin Zhang
0eca6b7c78 printk: add module parameter ignore_loglevel to control ignore_loglevel
We are enabling some power features on medfield.  To test suspend-2-RAM
conveniently, we need turn on/off ignore_loglevel frequently without
rebooting.

Add a module parameter, so users can change it by:
/sys/module/printk/parameters/ignore_loglevel

Signed-off-by: Yanmin Zhang <yanmin.zhang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:53 -07:00
Dan Ballard
73efc0394e kernel/sysctl.c: add cap_last_cap to /proc/sys/kernel
Userspace needs to know the highest valid capability of the running
kernel, which right now cannot reliably be retrieved from the header files
only.  The fact that this value cannot be determined properly right now
creates various problems for libraries compiled on newer header files
which are run on older kernels.  They assume capabilities are available
which actually aren't.  libcap-ng is one example.  And we ran into the
same problem with systemd too.

Now the capability is exported in /proc/sys/kernel/cap_last_cap.

[akpm@linux-foundation.org: make cap_last_cap const, per Ulrich]
Signed-off-by: Dan Ballard <dan@mindstab.net>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Ulrich Drepper <drepper@akkadia.org>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:53 -07:00
Vasily Averin
4ff819515b watchdog: move watchdog_*_all_cpus under CONFIG_SYSCTL
Fix compilation warnings for CONFIG_SYSCTL=n:

fixed compilation warnings in case of disabled CONFIG_SYSCTL
kernel/watchdog.c:483:13: warning: `watchdog_enable_all_cpus' defined but not used
kernel/watchdog.c:500:13: warning: `watchdog_disable_all_cpus' defined but not used

these functions are static and are used only in sysctl handler, so move
them inside #ifdef CONFIG_SYSCTL too

Signed-off-by: Vasily Averin <vvs@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:53 -07:00
Jeremy Fitzhardinge
f445027e4e stop_machine: make stop_machine safe and efficient to call early
Make stop_machine() safe to call early in boot, before SMP has been set
up, by simply calling the callback function directly if there's only one
CPU online.

[ Fixes from AKPM:
   - add comment
   - local_irq_flags, not save_flags
   - also call hard_irq_disable() for systems which need it

  Tejun suggested using an explicit flag rather than just looking at
  the online cpu count. ]

Cc: Tejun Heo <tj@kernel.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Tejun Heo <htejun@gmail.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:53 -07:00
Christoph Lameter
bc3e53f682 mm: distinguish between mlocked and pinned pages
Some kernel components pin user space memory (infiniband and perf) (by
increasing the page count) and account that memory as "mlocked".

The difference between mlocking and pinning is:

A. mlocked pages are marked with PG_mlocked and are exempt from
   swapping. Page migration may move them around though.
   They are kept on a special LRU list.

B. Pinned pages cannot be moved because something needs to
   directly access physical memory. They may not be on any
   LRU list.

I recently saw an mlockalled process where mm->locked_vm became
bigger than the virtual size of the process (!) because some
memory was accounted for twice:

Once when the page was mlocked and once when the Infiniband
layer increased the refcount because it needt to pin the RDMA
memory.

This patch introduces a separate counter for pinned pages and
accounts them seperately.

Signed-off-by: Christoph Lameter <cl@linux.com>
Cc: Mike Marciniszyn <infinipath@qlogic.com>
Cc: Roland Dreier <roland@kernel.org>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:46 -07:00
David Rientjes
c9f01245b6 oom: remove oom_disable_count
This removes mm->oom_disable_count entirely since it's unnecessary and
currently buggy.  The counter was intended to be per-process but it's
currently decremented in the exit path for each thread that exits, causing
it to underflow.

The count was originally intended to prevent oom killing threads that
share memory with threads that cannot be killed since it doesn't lead to
future memory freeing.  The counter could be fixed to represent all
threads sharing the same mm, but it's better to remove the count since:

 - it is possible that the OOM_DISABLE thread sharing memory with the
   victim is waiting on that thread to exit and will actually cause
   future memory freeing, and

 - there is no guarantee that a thread is disabled from oom killing just
   because another thread sharing its mm is oom disabled.

Signed-off-by: David Rientjes <rientjes@google.com>
Reported-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: Ying Han <yinghan@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:45 -07:00
Christopher Yeoh
fcf634098c Cross Memory Attach
The basic idea behind cross memory attach is to allow MPI programs doing
intra-node communication to do a single copy of the message rather than a
double copy of the message via shared memory.

The following patch attempts to achieve this by allowing a destination
process, given an address and size from a source process, to copy memory
directly from the source process into its own address space via a system
call.  There is also a symmetrical ability to copy from the current
process's address space into a destination process's address space.

- Use of /proc/pid/mem has been considered, but there are issues with
  using it:
  - Does not allow for specifying iovecs for both src and dest, assuming
    preadv or pwritev was implemented either the area read from or
  written to would need to be contiguous.
  - Currently mem_read allows only processes who are currently
  ptrace'ing the target and are still able to ptrace the target to read
  from the target. This check could possibly be moved to the open call,
  but its not clear exactly what race this restriction is stopping
  (reason  appears to have been lost)
  - Having to send the fd of /proc/self/mem via SCM_RIGHTS on unix
  domain socket is a bit ugly from a userspace point of view,
  especially when you may have hundreds if not (eventually) thousands
  of processes  that all need to do this with each other
  - Doesn't allow for some future use of the interface we would like to
  consider adding in the future (see below)
  - Interestingly reading from /proc/pid/mem currently actually
  involves two copies! (But this could be fixed pretty easily)

As mentioned previously use of vmsplice instead was considered, but has
problems.  Since you need the reader and writer working co-operatively if
the pipe is not drained then you block.  Which requires some wrapping to
do non blocking on the send side or polling on the receive.  In all to all
communication it requires ordering otherwise you can deadlock.  And in the
example of many MPI tasks writing to one MPI task vmsplice serialises the
copying.

There are some cases of MPI collectives where even a single copy interface
does not get us the performance gain we could.  For example in an
MPI_Reduce rather than copy the data from the source we would like to
instead use it directly in a mathops (say the reduce is doing a sum) as
this would save us doing a copy.  We don't need to keep a copy of the data
from the source.  I haven't implemented this, but I think this interface
could in the future do all this through the use of the flags - eg could
specify the math operation and type and the kernel rather than just
copying the data would apply the specified operation between the source
and destination and store it in the destination.

Although we don't have a "second user" of the interface (though I've had
some nibbles from people who may be interested in using it for intra
process messaging which is not MPI).  This interface is something which
hardware vendors are already doing for their custom drivers to implement
fast local communication.  And so in addition to this being useful for
OpenMPI it would mean the driver maintainers don't have to fix things up
when the mm changes.

There was some discussion about how much faster a true zero copy would
go. Here's a link back to the email with some testing I did on that:

http://marc.info/?l=linux-mm&m=130105930902915&w=2

There is a basic man page for the proposed interface here:

http://ozlabs.org/~cyeoh/cma/process_vm_readv.txt

This has been implemented for x86 and powerpc, other architecture should
mainly (I think) just need to add syscall numbers for the process_vm_readv
and process_vm_writev. There are 32 bit compatibility versions for
64-bit kernels.

For arch maintainers there are some simple tests to be able to quickly
verify that the syscalls are working correctly here:

http://ozlabs.org/~cyeoh/cma/cma-test-20110718.tgz

Signed-off-by: Chris Yeoh <yeohc@au1.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Cc: <linux-man@vger.kernel.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:44 -07:00
Paul Gortmaker
ec53cf23c0 irq: don't put module.h into irq.h for tracking irqgen modules.
Recent commit "irq: Track the  owner of irq descriptor" in
commit ID b6873807a7 placed module.h into linux/irq.h
but we are trying to limit module.h inclusion to just C files
that really need it, due to its size and number of children
includes.  This targets just reversing that include.

Add in the basic "struct module" since that is all we really need
to ensure things compile.  In theory, b687380 should have added the
module.h include to the irqdesc.h header as well, but the implicit
module.h everywhere presence masked this from showing up.  So give
it the "struct module" as well.

As for the C files, irqdesc.c is only using THIS_MODULE, so it
does not need module.h - give it export.h instead.  The C file
irq/manage.c is now (as of b687380) using try_module_get and
module_put and so it needs module.h (which it already has).

Also convert the irq_alloc_descs variants to macros, since all
they really do is is call the __irq_alloc_descs primitive.
This avoids including export.h and no debug info is lost.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:32:35 -04:00
Paul Gortmaker
6e5fdeedca kernel: Fix files explicitly needing EXPORT_SYMBOL infrastructure
These files were getting <linux/module.h> via an implicit non-obvious
path, but we want to crush those out of existence since they cost
time during compiles of processing thousands of lines of headers
for no reason.  Give them the lightweight header that just contains
the EXPORT_SYMBOL infrastructure.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:30:05 -04:00
Ilya Dryomov
d631097577 tracing: fix event_subsystem ref counting
Fix a bug introduced by e9dbfae5, which prevents event_subsystem from
ever being released.

Ref_count was added to keep track of subsystem users, not for counting
events.  Subsystem is created with ref_count = 1, so there is no need to
increment it for every event, we have nr_events for that.  Fix this by
touching ref_count only when we actually have a new user -
subsystem_open().

Cc: stable@vger.kernel.org
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Link: http://lkml.kernel.org/r/1320052062-7846-1-git-send-email-idryomov@gmail.com
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-10-31 13:59:23 -04:00
Paul Gortmaker
bdfa97bf72 kernel: fix up module header handling in rcutiny files
The file rcutiny.c does not need moduleparam.h header, as
there are no modparams in this file.

However rcutiny_plugin.h does define a module_init() and
a module_exit() and it uses the various MODULE_ macros, so
it really does need module.h included.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 09:20:13 -04:00
Paul Gortmaker
72a59aaada kernel: params.c needs module.h not moduleparam.h
Through various other implicit include paths, some files were
getting the full module.h file, and hence living the illusion
that they really only needed moduleparam.h -- but the reality
is that once you remove the module.h presence, these show up:

kernel/params.c:583: warning: ‘struct module_kobject’ declared inside parameter list

Such files really require module.h so simply make it so.  As the
file module.h grabs moduleparam.h on the fly, all will be well.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 09:20:13 -04:00
Paul Gortmaker
1596425fd7 kernel: ksysfs.c is implicitly using stat.h
With the module.h usage cleanup, we'll get this:

kernel/ksysfs.c:161: error: ‘S_IRUGO’ undeclared here (not in a function)
make[2]: *** [kernel/ksysfs.o] Error 1

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 09:20:13 -04:00
Paul Gortmaker
967d1f9062 kernel: fix two implicit header assumptions in irq_work.c
Up until now, this file was getting percpu.h because nearly every
file was implicitly getting module.h (and all its sub-includes).
But we want to clean that up, so call out percpu.h explicitly.
Otherwise we'll get things like this on an ARM build:

kernel/irq_work.c:48: error: expected declaration specifiers or '...' before 'irq_work_list'
kernel/irq_work.c:48: warning: type defaults to 'int' in declaration of 'DEFINE_PER_CPU'

The same thing was happening for builds on ARM for asm/processor.h

kernel/irq_work.c: In function 'irq_work_sync':
kernel/irq_work.c:166: error: implicit declaration of function 'cpu_relax'

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 09:20:12 -04:00
Paul Gortmaker
74da1ff713 kernel: fix several implicit usasges of kmod.h
These files were implicitly relying on <linux/kmod.h> coming in via
module.h, as without it we get things like:

kernel/power/suspend.c💯 error: implicit declaration of function ‘usermodehelper_disable’
kernel/power/suspend.c:109: error: implicit declaration of function ‘usermodehelper_enable’
kernel/power/user.c:254: error: implicit declaration of function ‘usermodehelper_disable’
kernel/power/user.c:261: error: implicit declaration of function ‘usermodehelper_enable’

kernel/sys.c:317: error: implicit declaration of function ‘usermodehelper_disable’
kernel/sys.c:1816: error: implicit declaration of function ‘call_usermodehelper_setup’
kernel/sys.c:1822: error: implicit declaration of function ‘call_usermodehelper_setfns’
kernel/sys.c:1824: error: implicit declaration of function ‘call_usermodehelper_exec’

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 09:20:12 -04:00
Paul Gortmaker
56d82e000c kernel: Add <linux/module.h> to files using it implicitly
These files are doing things like module_put and try_module_get
so they need to call out the module.h for explicit inclusion,
rather than getting it via <linux/device.h> which we ideally want
to remove the module.h inclusion from.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 09:20:12 -04:00
Paul Gortmaker
9984de1a5a kernel: Map most files to use export.h instead of module.h
The changed files were only including linux/module.h for the
EXPORT_SYMBOL infrastructure, and nothing else.  Revector them
onto the isolated export header for faster compile times.

Nothing to see here but a whole lot of instances of:

  -#include <linux/module.h>
  +#include <linux/export.h>

This commit is only changing the kernel dir; next targets
will probably be mm, fs, the arch dirs, etc.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 09:20:12 -04:00
Paul Gortmaker
9a41845513 range: fix bogus misuse of module.h to get printk()
This file isn't doing anything with modules and so it should
not be including <linux/module.h> just to get basic stuff
like printk() and min/max.  Revector it to <linux/kernel.h>.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 09:20:11 -04:00
Arnd Bergmann
08cab72f91 Merge branch 'dt/gic' into next/dt
Conflicts:
	arch/arm/include/asm/localtimer.h
	arch/arm/mach-msm/board-msm8x60.c
	arch/arm/mach-omap2/board-generic.c
2011-10-31 14:08:10 +01:00
Rob Herring
6d274309d0 irq: support domains with non-zero hwirq base
Interrupt controllers can have non-zero starting value for h/w irq numbers.
Adding support in irq_domain allows the domain hwirq numbering to match
the interrupt controllers' numbering.

As this makes looping over irqs for a domain more complicated, add loop
iterators to iterate over all hwirqs and irqs for a domain.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Reviewed-by: Jamie Iles <jamie@jamieiles.com>
Tested-by: Thomas Abraham <thomas.abraham@linaro.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
2011-10-31 14:03:23 +01:00
Martin Schwidefsky
638ad34a88 [S390] sparse: fix sparse warnings about missing prototypes
Add prototypes and includes for functions used in different modules.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-10-30 15:16:46 +01:00
Michael Holzheu
558df7209e [S390] kdump: Add infrastructure for unmapping crashkernel memory
This patch introduces a mechanism that allows architecture backends to
remove page tables for the crashkernel memory. This can protect the loaded
kdump kernel from being overwritten by broken kernel code.  Two new
functions crash_map_reserved_pages() and crash_unmap_reserved_pages() are
added that can be implemented by architecture code.  The
crash_map_reserved_pages() function is called before and
crash_unmap_reserved_pages() after the crashkernel segments are loaded.  The
functions are also called in crash_shrink_memory() to create/remove page
tables when the crashkernel memory size is reduced.

To support architectures that have large pages this patch also introduces
a new define KEXEC_CRASH_MEM_ALIGN. The crashkernel start and size must
always be aligned with KEXEC_CRASH_MEM_ALIGN.

Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-10-30 15:16:42 +01:00
Michael Holzheu
fa8ff292bb [S390] kdump: Initialize vmcoreinfo note at startup
Currently the vmcoreinfo note is only initialized in case of kdump. On s390
it is possible to create kernel dumps with other dump mechanisms than kdump
(e.g. via hypervisor dump or stand-alone dump tools). For those dumps it
would also be desirable to include the vmcoreinfo data. To accomplish this,
with this patch the vmcoreinfo ELF note is always initialized, not only in
case of a (kdump) crash. On s390 we will add an ABI defined pointer at
a well known address to vmcoreinfo so that dump analysis tools are able to
find this information.

In particular on s390 we have a tool named zgetdump. With this tool it is
possible to convert dump formats on the fly using fuse. E.g. you can mount a
s390 stand-alone dump as ELF dump. When this is done, the tool finds the
vmcoreinfo in the stand-alone dump via the well known ABI defined address and
it creates the respective VMCOREINFO ELF note in the output ELF dump. This then
can be used e.g. by makedumpfile for dump filtering.  No more need for a
vmlinux file with debug information.

So this will look like the following:
$ zgetdump --mount standalone.dump -f elf /mnt
$ ls /mnt
  dump.elf
$ readelf -n /mnt/dump.elf
$ ...
  VMCOREINFO            0x00000474      Unknown note type: (0x00000000)
$ makedumpfile -c -d 31 /mnt/dump.elf dump.kdump

Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-10-30 15:16:42 +01:00
Michael Holzheu
d3bf37955d [S390] kdump: Add size to elfcorehdr kernel parameter
Currently only the address of the pre-allocated ELF header is passed with
the elfcorehdr= kernel parameter. In order to reserve memory for the header
in the 2nd kernel also the size is required. Current kdump architecture
backends use different methods to do that, e.g. x86 uses the memmap= kernel
parameter. On s390 there is no easy way to transfer this information.
Therefore the elfcorehdr kernel parameter is extended to also pass the size.
This now can also be used as standard mechanism by all future kdump
architecture backends.

The syntax of the kernel parameter is extended as follows:

elfcorehdr=[size[KMG]@]offset[KMG]

This change is backward compatible because elfcorehdr=size is still allowed.

Acked-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-10-30 15:16:41 +01:00
Michael Holzheu
3d214faea6 [S390] kdump: Add KEXEC_CRASH_CONTROL_MEMORY_LIMIT
On s390 there is a different KEXEC_CONTROL_MEMORY_LIMIT for the normal and
the kdump kexec case. Therefore this patch introduces a new macro
KEXEC_CRASH_CONTROL_MEMORY_LIMIT. This is set to
KEXEC_CONTROL_MEMORY_LIMIT for all architectures that do not define
KEXEC_CRASH_CONTROL_MEMORY_LIMIT.

Acked-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-10-30 15:16:41 +01:00
Linus Torvalds
41684f67af Merge branch 'gpio/next' of git://git.secretlab.ca/git/linux-2.6
* 'gpio/next' of git://git.secretlab.ca/git/linux-2.6:
  h8300: Move gpio.h to gpio-internal.h
  gpio: pl061: add DT binding support
  gpio: fix build error in include/asm-generic/gpio.h
  gpiolib: Ensure struct gpio is always defined
  irq: Add EXPORT_SYMBOL_GPL to function of irq generic-chip
  gpio-ml-ioh: Use NUMA_NO_NODE not GFP_KERNEL
  gpio-pch: Use NUMA_NO_NODE not GFP_KERNEL
  gpio: langwell: ensure alternate function is cleared
  gpio-pch: Support interrupt function
  gpio-pch: Save register value in suspend()
  gpio-pch: modify gpio_nums and mask
  gpio-pch: support ML7223 IOH n-Bus
  gpio-pch: add spinlock in suspend/resume processing
  gpio-pch: Delete invalid "restore" code in suspend()
  gpio-ml-ioh: Fix suspend/resume issue
  gpio-ml-ioh: Support interrupt function
  gpio-ml-ioh: Delete unnecessary code
  gpio/mxc: add chained_irq_enter/exit() to mx3_gpio_irq_handler()
  gpio/nomadik: use genirq core to track enablement
  gpio/nomadik: disable clocks when unused
2011-10-29 07:27:45 -07:00
Linus Torvalds
1fdb24e969 Merge branch 'devel-stable' of http://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm
* 'devel-stable' of http://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm: (178 commits)
  ARM: 7139/1: fix compilation with CONFIG_ARM_ATAG_DTB_COMPAT and large TEXT_OFFSET
  ARM: gic, local timers: use the request_percpu_irq() interface
  ARM: gic: consolidate PPI handling
  ARM: switch from NO_MACH_MEMORY_H to NEED_MACH_MEMORY_H
  ARM: mach-s5p64x0: remove mach/memory.h
  ARM: mach-s3c64xx: remove mach/memory.h
  ARM: plat-mxc: remove mach/memory.h
  ARM: mach-prima2: remove mach/memory.h
  ARM: mach-zynq: remove mach/memory.h
  ARM: mach-bcmring: remove mach/memory.h
  ARM: mach-davinci: remove mach/memory.h
  ARM: mach-pxa: remove mach/memory.h
  ARM: mach-ixp4xx: remove mach/memory.h
  ARM: mach-h720x: remove mach/memory.h
  ARM: mach-vt8500: remove mach/memory.h
  ARM: mach-s5pc100: remove mach/memory.h
  ARM: mach-tegra: remove mach/memory.h
  ARM: plat-tcc: remove mach/memory.h
  ARM: mach-mmp: remove mach/memory.h
  ARM: mach-cns3xxx: remove mach/memory.h
  ...

Fix up mostly pretty trivial conflicts in:
 - arch/arm/Kconfig
 - arch/arm/include/asm/localtimer.h
 - arch/arm/kernel/Makefile
 - arch/arm/mach-shmobile/board-ap4evb.c
 - arch/arm/mach-u300/core.c
 - arch/arm/mm/dma-mapping.c
 - arch/arm/mm/proc-v7.S
 - arch/arm/plat-omap/Kconfig
largely due to some CONFIG option renaming (ie CONFIG_PM_SLEEP ->
CONFIG_ARM_CPU_SUSPEND for the arm-specific suspend code etc) and
addition of NEED_MACH_MEMORY_H next to HAVE_IDE.
2011-10-28 12:02:27 -07:00
Linus Torvalds
39adff5f69 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  time, s390: Get rid of compile warning
  dw_apb_timer: constify clocksource name
  time: Cleanup old CONFIG_GENERIC_TIME references that snuck in
  time: Change jiffies_to_clock_t() argument type to unsigned long
  alarmtimers: Fix error handling
  clocksource: Make watchdog reset lockless
  posix-cpu-timers: Cure SMP accounting oddities
  s390: Use direct ktime path for s390 clockevent device
  clockevents: Add direct ktime programming function
  clockevents: Make minimum delay adjustments configurable
  nohz: Remove "Switched to NOHz mode" debugging messages
  proc: Consider NO_HZ when printing idle and iowait times
  nohz: Make idle/iowait counter update conditional
  nohz: Fix update_ts_time_stat idle accounting
  cputime: Clean up cputime_to_usecs and usecs_to_cputime macros
  alarmtimers: Rework RTC device selection using class interface
  alarmtimers: Add try_to_cancel functionality
  alarmtimers: Add more refined alarm state tracking
  alarmtimers: Remove period from alarm structure
  alarmtimers: Remove interval cap limit hack
  ...
2011-10-26 17:15:03 +02:00
Linus Torvalds
8a4a8918ed Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (46 commits)
  llist: Add back llist_add_batch() and llist_del_first() prototypes
  sched: Don't use tasklist_lock for debug prints
  sched: Warn on rt throttling
  sched: Unify the ->cpus_allowed mask copy
  sched: Wrap scheduler p->cpus_allowed access
  sched: Request for idle balance during nohz idle load balance
  sched: Use resched IPI to kick off the nohz idle balance
  sched: Fix idle_cpu()
  llist: Remove cpu_relax() usage in cmpxchg loops
  sched: Convert to struct llist
  llist: Add llist_next()
  irq_work: Use llist in the struct irq_work logic
  llist: Return whether list is empty before adding in llist_add()
  llist: Move cpu_relax() to after the cmpxchg()
  llist: Remove the platform-dependent NMI checks
  llist: Make some llist functions inline
  sched, tracing: Show PREEMPT_ACTIVE state in trace_sched_switch
  sched: Remove redundant test in check_preempt_tick()
  sched: Add documentation for bandwidth control
  sched: Return unused runtime on group dequeue
  ...
2011-10-26 17:08:43 +02:00
Linus Torvalds
7115e3fcf4 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (121 commits)
  perf symbols: Increase symbol KSYM_NAME_LEN size
  perf hists browser: Refuse 'a' hotkey on non symbolic views
  perf ui browser: Use libslang to read keys
  perf tools: Fix tracing info recording
  perf hists browser: Elide DSO column when it is set to just one DSO, ditto for threads
  perf hists: Don't consider filtered entries when calculating column widths
  perf hists: Don't decay total_period for filtered entries
  perf hists browser: Honour symbol_conf.show_{nr_samples,total_period}
  perf hists browser: Do not exit on tab key with single event
  perf annotate browser: Don't change selection line when returning from callq
  perf tools: handle endianness of feature bitmap
  perf tools: Add prelink suggestion to dso update message
  perf script: Fix unknown feature comment
  perf hists browser: Apply the dso and thread filters when merging new batches
  perf hists: Move the dso and thread filters from hist_browser
  perf ui browser: Honour the xterm colors
  perf top tui: Give color hints just on the percentage, like on --stdio
  perf ui browser: Make the colors configurable and change the defaults
  perf tui: Remove unneeded call to newtCls on startup
  perf hists: Don't format the percentage on hist_entry__snprintf
  ...

Fix up conflicts in arch/x86/kernel/kprobes.c manually.

Ingo's tree did the insane "add volatile to const array", which just
doesn't make sense ("volatile const"?).  But we could remove the const
*and* make the array volatile to make doubly sure that gcc doesn't
optimize it away..

Also fix up kernel/trace/ring_buffer.c non-data-conflicts manually: the
reader_lock has been turned into a raw lock by the core locking merge,
and there was a new user of it introduced in this perf core merge.  Make
sure that new use also uses the raw accessor functions.
2011-10-26 17:03:38 +02:00
Linus Torvalds
1f6e05171b Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Add IRQF_RESUME_EARLY and resume such IRQs earlier
  genirq: Fix fatfinered fixup really
  genirq: percpu: allow interrupt type to be set at enable time
  genirq: Add support for per-cpu dev_id interrupts
  genirq: Add IRQCHIP_SKIP_SET_WAKE flag
2011-10-26 16:44:09 +02:00
Linus Torvalds
19b4a8d520 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (45 commits)
  rcu: Move propagation of ->completed from rcu_start_gp() to rcu_report_qs_rsp()
  rcu: Remove rcu_needs_cpu_flush() to avoid false quiescent states
  rcu: Wire up RCU_BOOST_PRIO for rcutree
  rcu: Make rcu_torture_boost() exit loops at end of test
  rcu: Make rcu_torture_fqs() exit loops at end of test
  rcu: Permit rt_mutex_unlock() with irqs disabled
  rcu: Avoid having just-onlined CPU resched itself when RCU is idle
  rcu: Suppress NMI backtraces when stall ends before dump
  rcu: Prohibit grace periods during early boot
  rcu: Simplify unboosting checks
  rcu: Prevent early boot set_need_resched() from __rcu_pending()
  rcu: Dump local stack if cannot dump all CPUs' stacks
  rcu: Move __rcu_read_unlock()'s barrier() within if-statement
  rcu: Improve rcu_assign_pointer() and RCU_INIT_POINTER() documentation
  rcu: Make rcu_assign_pointer() unconditionally insert a memory barrier
  rcu: Make rcu_implicit_dynticks_qs() locals be correct size
  rcu: Eliminate in_irq() checks in rcu_enter_nohz()
  nohz: Remove nohz_cpu_mask
  rcu: Document interpretation of RCU-lockdep splats
  rcu: Allow rcutorture's stat_interval parameter to be changed at runtime
  ...
2011-10-26 16:26:53 +02:00
Linus Torvalds
3cfef95246 Merge branch 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
  rtmutex: Add missing rcu_read_unlock() in debug_rt_mutex_print_deadlock()
  lockdep: Comment all warnings
  lib: atomic64: Change the type of local lock to raw_spinlock_t
  locking, lib/atomic64: Annotate atomic64_lock::lock as raw
  locking, x86, iommu: Annotate qi->q_lock as raw
  locking, x86, iommu: Annotate irq_2_ir_lock as raw
  locking, x86, iommu: Annotate iommu->register_lock as raw
  locking, dma, ipu: Annotate bank_lock as raw
  locking, ARM: Annotate low level hw locks as raw
  locking, drivers/dca: Annotate dca_lock as raw
  locking, powerpc: Annotate uic->lock as raw
  locking, x86: mce: Annotate cmci_discover_lock as raw
  locking, ACPI: Annotate c3_lock as raw
  locking, oprofile: Annotate oprofilefs lock as raw
  locking, video: Annotate vga console lock as raw
  locking, latencytop: Annotate latency_lock as raw
  locking, timer_stats: Annotate table_lock as raw
  locking, rwsem: Annotate inner lock as raw
  locking, semaphores: Annotate inner lock as raw
  locking, sched: Annotate thread_group_cputimer as raw
  ...

Fix up conflicts in kernel/posix-cpu-timers.c manually: making
cputimer->cputime a raw lock conflicted with the ABBA fix in commit
bcd5cff721 ("cputimer: Cure lock inversion").
2011-10-26 16:17:32 +02:00
Linus Torvalds
2355e42903 Merge git://github.com/rustyrussell/linux
* git://github.com/rustyrussell/linux:
  params: make dashes and underscores in parameter names truly equal
  kmod: prevent kmod_loop_msg overflow in __request_module()
2011-10-26 14:39:47 +02:00
Michal Schmidt
b1e4d20cbf params: make dashes and underscores in parameter names truly equal
The user may use "foo-bar" for a kernel parameter defined as "foo_bar".
Make sure it works the other way around too.

Apply the equality of dashes and underscores on early_params and __setup
params as well.

The example given in Documentation/kernel-parameters.txt indicates that
this is the intended behaviour.

With the patch the kernel accepts "log-buf-len=1M" as expected.
https://bugzilla.redhat.com/show_bug.cgi?id=744545

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (neatened implementations)
2011-10-26 13:10:39 +10:30
Jiri Kosina
37252db6aa kmod: prevent kmod_loop_msg overflow in __request_module()
Due to post-increment in condition of kmod_loop_msg in __request_module(),
the system log can be spammed by much more than 5 instances of the 'runaway
loop' message if the number of events triggering it makes the kmod_loop_msg
to overflow.

Fix that by making sure we never increment it past the threshold.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
CC: stable@kernel.org
2011-10-26 13:10:39 +10:30
Jeremy Fitzhardinge
97ce2c88f9 jump-label: initialize jump-label subsystem much earlier
Initialize jump_labels much, much earlier, so they're available for use
during system setup.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
2011-10-25 11:55:15 -07:00
Jeremy Fitzhardinge
20284aa77c jump_label: add arch_jump_label_transform_static() to optimise non-live code updates
When updating a newly loaded module, the code is definitely not yet
executing on any processor, so it can be updated with no need for any
heavyweight synchronization.

This patch adds arch_jump_label_static() which is implemented as
arch_jump_label_transform() by default, but architectures can override
it if it avoids, say, a call to stop_machine().

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Jason Baron <jbaron@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
2011-10-25 11:54:31 -07:00
Jeremy Fitzhardinge
37348804e0 jump_label: if a key has already been initialized, don't nop it out
If a key has been enabled before jump_label_init() is called, don't
nop it out.

This removes arch_jump_label_text_poke_early() (which can only nop
out a site) and uses arch_jump_label_transform() instead.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Jason Baron <jbaron@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
2011-10-25 11:54:15 -07:00
Jeremy Fitzhardinge
189c3fd68c stop_machine: make stop_machine safe and efficient to call early
Make stop_machine() safe to call early in boot, before stop_machine()
has been set up, by simply calling the callback function directly if
there's only one CPU online.

[ Fixes from AKPM:
   - add comment
   - local_irq_flags, not save_flags
   - also call hard_irq_disable() for systems which need it

  Tejun suggested using an explicit flag rather than just looking at
  the online cpu count. ]

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
2011-10-25 11:54:04 -07:00
Linus Torvalds
7e0bb71e75 Merge branch 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
* 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (63 commits)
  PM / Clocks: Remove redundant NULL checks before kfree()
  PM / Documentation: Update docs about suspend and CPU hotplug
  ACPI / PM: Add Sony VGN-FW21E to nonvs blacklist.
  ARM: mach-shmobile: sh7372 A4R support (v4)
  ARM: mach-shmobile: sh7372 A3SP support (v4)
  PM / Sleep: Mark devices involved in wakeup signaling during suspend
  PM / Hibernate: Improve performance of LZO/plain hibernation, checksum image
  PM / Hibernate: Do not initialize static and extern variables to 0
  PM / Freezer: Make fake_signal_wake_up() wake TASK_KILLABLE tasks too
  PM / Hibernate: Add resumedelay kernel param in addition to resumewait
  MAINTAINERS: Update linux-pm list address
  PM / ACPI: Blacklist Vaio VGN-FW520F machine known to require acpi_sleep=nonvs
  PM / ACPI: Blacklist Sony Vaio known to require acpi_sleep=nonvs
  PM / Hibernate: Add resumewait param to support MMC-like devices as resume file
  PM / Hibernate: Fix typo in a kerneldoc comment
  PM / Hibernate: Freeze kernel threads after preallocating memory
  PM: Update the policy on default wakeup settings
  PM / VT: Cleanup #if defined uglyness and fix compile error
  PM / Suspend: Off by one in pm_suspend()
  PM / Hibernate: Include storage keys in hibernation image on s390
  ...
2011-10-25 15:18:39 +02:00
Linus Torvalds
8a9ea3237e Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1745 commits)
  dp83640: free packet queues on remove
  dp83640: use proper function to free transmit time stamping packets
  ipv6: Do not use routes from locally generated RAs
  |PATCH net-next] tg3: add tx_dropped counter
  be2net: don't create multiple RX/TX rings in multi channel mode
  be2net: don't create multiple TXQs in BE2
  be2net: refactor VF setup/teardown code into be_vf_setup/clear()
  be2net: add vlan/rx-mode/flow-control config to be_setup()
  net_sched: cls_flow: use skb_header_pointer()
  ipv4: avoid useless call of the function check_peer_pmtu
  TCP: remove TCP_DEBUG
  net: Fix driver name for mdio-gpio.c
  ipv4: tcp: fix TOS value in ACK messages sent from TIME_WAIT
  rtnetlink: Add missing manual netlink notification in dev_change_net_namespaces
  ipv4: fix ipsec forward performance regression
  jme: fix irq storm after suspend/resume
  route: fix ICMP redirect validation
  net: hold sock reference while processing tx timestamps
  tcp: md5: add more const attributes
  Add ethtool -g support to virtio_net
  ...

Fix up conflicts in:
 - drivers/net/Kconfig:
	The split-up generated a trivial conflict with removal of a
	stale reference to Documentation/networking/net-modules.txt.
	Remove it from the new location instead.
 - fs/sysfs/dir.c:
	Fairly nasty conflicts with the sysfs rb-tree usage, conflicting
	with Eric Biederman's changes for tagged directories.
2011-10-25 13:25:22 +02:00
Linus Torvalds
1be025d3cb Merge branch 'usb-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
* 'usb-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (260 commits)
  usb: renesas_usbhs: fixup inconsistent return from usbhs_pkt_push()
  usb/isp1760: Allow to optionally trigger low-level chip reset via GPIOLIB.
  USB: gadget: midi: memory leak in f_midi_bind_config()
  USB: gadget: midi: fix range check in f_midi_out_open()
  QE/FHCI: fixed the CONTROL bug
  usb: renesas_usbhs: tidyup for smatch warnings
  USB: Fix USB Kconfig dependency problem on 85xx/QoirQ platforms
  EHCI: workaround for MosChip controller bug
  usb: gadget: file_storage: fix race on unloading
  USB: ftdi_sio.c: Use ftdi async_icount structure for TIOCMIWAIT, as in other drivers
  USB: ftdi_sio.c:Fill MSR fields of the ftdi async_icount structure
  USB: ftdi_sio.c: Fill LSR fields of the ftdi async_icount structure
  USB: ftdi_sio.c:Fill TX field of the ftdi async_icount structure
  USB: ftdi_sio.c: Fill the RX field of the ftdi async_icount structure
  USB: ftdi_sio.c: Basic icount infrastructure for ftdi_sio
  usb/isp1760: Let OF bindings depend on general CONFIG_OF instead of PPC_OF .
  USB: ftdi_sio: Support TI/Luminary Micro Stellaris BD-ICDI Board
  USB: Fix runtime wakeup on OHCI
  xHCI/USB: Make xHCI driver have a BOS descriptor.
  usb: gadget: add new usb gadget for ACM and mass storage
  ...
2011-10-25 12:23:15 +02:00
Linus Torvalds
59e5253417 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (59 commits)
  MAINTAINERS: linux-m32r is moderated for non-subscribers
  linux@lists.openrisc.net is moderated for non-subscribers
  Drop default from "DM365 codec select" choice
  parisc: Kconfig: cleanup Kernel page size default
  Kconfig: remove redundant CONFIG_ prefix on two symbols
  cris: remove arch/cris/arch-v32/lib/nand_init.S
  microblaze: add missing CONFIG_ prefixes
  h8300: drop puzzling Kconfig dependencies
  MAINTAINERS: microblaze-uclinux@itee.uq.edu.au is moderated for non-subscribers
  tty: drop superfluous dependency in Kconfig
  ARM: mxc: fix Kconfig typo 'i.MX51'
  Fix file references in Kconfig files
  aic7xxx: fix Kconfig references to READMEs
  Fix file references in drivers/ide/
  thinkpad_acpi: Fix printk typo 'bluestooth'
  bcmring: drop commented out line in Kconfig
  btmrvl_sdio: fix typo 'btmrvl_sdio_sd6888'
  doc: raw1394: Trivial typo fix
  CIFS: Don't free volume_info->UNC until we are entirely done with it.
  treewide: Correct spelling of successfully in comments
  ...
2011-10-25 12:11:02 +02:00
Linus Torvalds
36b8d186e6 Merge branch 'next' of git://selinuxproject.org/~jmorris/linux-security
* 'next' of git://selinuxproject.org/~jmorris/linux-security: (95 commits)
  TOMOYO: Fix incomplete read after seek.
  Smack: allow to access /smack/access as normal user
  TOMOYO: Fix unused kernel config option.
  Smack: fix: invalid length set for the result of /smack/access
  Smack: compilation fix
  Smack: fix for /smack/access output, use string instead of byte
  Smack: domain transition protections (v3)
  Smack: Provide information for UDS getsockopt(SO_PEERCRED)
  Smack: Clean up comments
  Smack: Repair processing of fcntl
  Smack: Rule list lookup performance
  Smack: check permissions from user space (v2)
  TOMOYO: Fix quota and garbage collector.
  TOMOYO: Remove redundant tasklist_lock.
  TOMOYO: Fix domain transition failure warning.
  TOMOYO: Remove tomoyo_policy_memory_lock spinlock.
  TOMOYO: Simplify garbage collector.
  TOMOYO: Fix make namespacecheck warnings.
  target: check hex2bin result
  encrypted-keys: check hex2bin result
  ...
2011-10-25 09:45:31 +02:00
David S. Miller
1805b2f048 Merge branch 'master' of ra.kernel.org:/pub/scm/linux/kernel/git/davem/net 2011-10-24 18:18:09 -04:00
Rob Herring
3a82543642 Merge remote-tracking branch 'rmk/devel-stable' into HEAD 2011-10-24 14:02:37 -05:00
Nobuhiro Iwamatsu
825de2e900 irq: Add EXPORT_SYMBOL_GPL to function of irq generic-chip
Some functions of irq generic-chip is undefined, because
EXPORT_SYMBOL_GPL is not set to these.

ERROR: "irq_setup_generic_chip" [drivers/gpio/gpio-pch.ko] undefined!
ERROR: "irq_alloc_generic_chip" [drivers/gpio/gpio-pch.ko] undefined!
ERROR: "irq_setup_generic_chip" [drivers/gpio/gpio-ml-ioh.ko] undefined!
ERROR: "irq_alloc_generic_chip" [drivers/gpio/gpio-ml-ioh.ko] undefined!

This is revised that EXPORT_SYMBOL_GPL can be added and referred
to in functions.

Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-10-24 15:22:33 +02:00
Russell King
34471a9168 Merge branch 'ppi-irq-core-for-rmk' of git://github.com/mzyngier/arm-platforms into devel-stable 2011-10-23 14:42:30 +01:00
Peter Zijlstra
bcd5cff721 cputimer: Cure lock inversion
There's a lock inversion between the cputimer->lock and rq->lock;
notably the two callchains involved are:

 update_rlimit_cpu()
   sighand->siglock
   set_process_cpu_timer()
     cpu_timer_sample_group()
       thread_group_cputimer()
         cputimer->lock
         thread_group_cputime()
           task_sched_runtime()
             ->pi_lock
             rq->lock

 scheduler_tick()
   rq->lock
   task_tick_fair()
     update_curr()
       account_group_exec()
         cputimer->lock

Where the first one is enabling a CLOCK_PROCESS_CPUTIME_ID timer, and
the second one is keeping up-to-date.

This problem was introduced by e8abccb719 ("posix-cpu-timers: Cure
SMP accounting oddities").

Cure the problem by removing the cputimer->lock and rq->lock nesting,
this leaves concurrent enablers doing duplicate work, but the time
wasted should be on the same order otherwise wasted spinning on the
lock and the greater-than assignment filter should ensure we preserve
monotonicity.

Reported-by: Dave Jones <davej@redhat.com>
Reported-by: Simon Kirby <sim@hostway.ca>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: stable@kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: http://lkml.kernel.org/r/1318928713.21167.4.camel@twins
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-10-18 11:36:59 +02:00
Linus Torvalds
a84a79e4d3 Avoid using variable-length arrays in kernel/sys.c
The size is always valid, but variable-length arrays generate worse code
for no good reason (unless the function happens to be inlined and the
compiler sees the length for the simple constant it is).

Also, there seems to be some code generation problem on POWER, where
Henrik Bakken reports that register r28 can get corrupted under some
subtle circumstances (interrupt happening at the wrong time?).  That all
indicates some seriously broken compiler issues, but since variable
length arrays are bad regardless, there's little point in trying to
chase it down.

"Just don't do that, then".

Reported-by: Henrik Grindal Bakken <henribak@cisco.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-17 08:24:24 -07:00
Ian Campbell
9bab0b7fba genirq: Add IRQF_RESUME_EARLY and resume such IRQs earlier
This adds a mechanism to resume selected IRQs during syscore_resume
instead of dpm_resume_noirq.

Under Xen we need to resume IRQs associated with IPIs early enough
that the resched IPI is unmasked and we can therefore schedule
ourselves out of the stop_machine where the suspend/resume takes
place.

This issue was introduced by 676dc3cf5b "xen: Use IRQF_FORCE_RESUME".

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Jeremy Fitzhardinge <Jeremy.Fitzhardinge@citrix.com>
Cc: xen-devel <xen-devel@lists.xensource.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Link: http://lkml.kernel.org/r/1318713254.11016.52.camel@dagon.hellion.org.uk
Cc: stable@kernel.org (at least to 2.6.32.y)
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-10-17 11:42:49 +02:00
Bojan Smojver
081a9d043c PM / Hibernate: Improve performance of LZO/plain hibernation, checksum image
Use threads for LZO compression/decompression on hibernate/thaw.
Improve buffering on hibernate/thaw.
Calculate/verify CRC32 of the image pages on hibernate/thaw.

In my testing, this improved write/read speed by a factor of about two.

Signed-off-by: Bojan Smojver <bojan@rexursive.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-16 23:30:38 +02:00
Barry Song
d231ff1af7 PM / Hibernate: Do not initialize static and extern variables to 0
Static and extern variables in kernel/power/hibernate.c need not be
initialized to 0 explicitly, so remove those initializations.

[rjw: Modified subject, added changelog.]

Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-16 23:30:38 +02:00
Jeff Layton
27920651fe PM / Freezer: Make fake_signal_wake_up() wake TASK_KILLABLE tasks too
TASK_KILLABLE is often used to put tasks to sleep for quite some time.
One of the most common uses is to put tasks to sleep while waiting for
replies from a server on a networked filesystem (such as CIFS or NFS).

Unfortunately, fake_signal_wake_up does not currently wake up tasks
that are sleeping in TASK_KILLABLE state. This means that even if the
code were in place to allow them to freeze while in this sleep, it
wouldn't work anyway.

This patch changes this function to wake tasks in this state as well.
This should be harmless -- if the code doing the sleeping doesn't have
handling to deal with freezer events, it should just go back to sleep.
If it does, then this will allow that code to do the right thing.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-16 23:30:37 +02:00
Barry Song
f126f7334f PM / Hibernate: Add resumedelay kernel param in addition to resumewait
Patch "PM / Hibernate: Add resumewait param to support MMC-like
devices as resume file" added the resumewait kernel command line
option.  The present patch adds resumedelay so that
resumewait/delay were analogous to rootwait/delay.

[rjw: Modified the subject and changelog slightly.]

Signed-off-by: Barry Song <baohua.song@csr.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-16 23:30:37 +02:00
Barry Song
6f8d7022a8 PM / Hibernate: Add resumewait param to support MMC-like devices as resume file
Some devices like MMC are async detected very slow. For example,
drivers/mmc/host/sdhci.c launches a 200ms delayed work to detect
MMC partitions then add disk.

We have wait_for_device_probe() and scsi_complete_async_scans()
before calling swsusp_check(), but it is not enough to wait for MMC.

This patch adds resumewait kernel param just like rootwait so
that we have enough time to wait until MMC is ready. The difference is
that we wait for resume partition whereas rootwait waits for rootfs
partition (which may be on a different device).

This patch will make hibernation support many embedded products
without SCSI devices, but with devices like MMC.

[rjw: Modified the changelog slightly.]

Signed-off-by: Barry Song <Baohua.Song@csr.com>
Reviewed-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-16 23:30:36 +02:00
Barry Song
21e82808fc PM / Hibernate: Fix typo in a kerneldoc comment
Fix a typo in a function name in the kerneldoc comment next to
resume_target_kernel().

[rjw: Changed the subject slightly, added the changelog.]

Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-16 23:28:52 +02:00
Rafael J. Wysocki
2aede851dd PM / Hibernate: Freeze kernel threads after preallocating memory
There is a problem with the current ordering of hibernate code which
leads to deadlocks in some filesystems' memory shrinkers.  Namely,
some filesystems use freezable kernel threads that are inactive when
the hibernate memory preallocation is carried out.  Those same
filesystems use memory shrinkers that may be triggered by the
hibernate memory preallocation.  If those memory shrinkers wait for
the frozen kernel threads, the hibernate process deadlocks (this
happens with XFS, for one example).

Apparently, it is not technically viable to redesign the filesystems
in question to avoid the situation described above, so the only
possible solution of this issue is to defer the freezing of kernel
threads until the hibernate memory preallocation is done, which is
implemented by this change.

Unfortunately, this requires the memory preallocation to be done
before the "prepare" stage of device freeze, so after this change the
only way drivers can allocate additional memory for their freeze
routines in a clean way is to use PM notifiers.

Reported-by: Christoph <cr2005@u-club.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-16 23:28:52 +02:00
H Hartley Sweeten
37cce26b32 PM / VT: Cleanup #if defined uglyness and fix compile error
Introduce the config option CONFIG_VT_CONSOLE_SLEEP in order to cleanup
the #if defined ugliness for the vt suspend support functions. Note that
CONFIG_VT_CONSOLE is already dependant on CONFIG_VT.

The function pm_set_vt_switch is actually dependant on CONFIG_VT and not
CONFIG_PM_SLEEP. This fixes a compile error when CONFIG_PM_SLEEP is
not set:

drivers/tty/vt/vt_ioctl.c:1794: error: redefinition of 'pm_set_vt_switch'
include/linux/suspend.h:17: error: previous definition of 'pm_set_vt_switch' was here

Also, remove the incorrect path from the comment in console.c.

[rjw: Replaced #if defined() with #ifdef in suspend.h.]

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-16 23:28:51 +02:00
Dan Carpenter
528f7ce6e4 PM / Suspend: Off by one in pm_suspend()
In enter_state() we use "state" as an offset for the pm_states[]
array.  The pm_states[] array only has PM_SUSPEND_MAX elements so
this test is off by one.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: stable@kernel.org
2011-10-16 23:27:46 +02:00
Martin Schwidefsky
85055dd805 PM / Hibernate: Include storage keys in hibernation image on s390
For s390 there is one additional byte associated with each page,
the storage key. This byte contains the referenced and changed
bits and needs to be included into the hibernation image.
If the storage keys are not restored to their previous state all
original pages would appear to be dirty. This can cause
inconsistencies e.g. with read-only filesystems.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-16 23:27:46 +02:00
Rafael J. Wysocki
ca123102f6 PM: Fix build issue in main.c for CONFIG_PM_SLEEP unset
Suspend statistics should depend on CONFIG_PM_SLEEP, so make that
happen.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-16 23:27:46 +02:00
ShuoX Liu
2a77c46de1 PM / Suspend: Add statistics debugfs file for suspend to RAM
Record S3 failure time about each reason and the latest two failed
devices' names in S3 progress.
We can check it through 'suspend_stats' entry in debugfs.

The motivation of the patch:

We are enabling power features on Medfield. Comparing with PC/notebook,
a mobile enters/exits suspend-2-ram (we call it s3 on Medfield) far
more frequently. If it can't enter suspend-2-ram in time, the power
might be used up soon.

We often find sometimes, a device suspend fails. Then, system retries
s3 over and over again. As display is off, testers and developers
don't know what happens.

Some testers and developers complain they don't know if system
tries suspend-2-ram, and what device fails to suspend. They need
such info for a quick check. The patch adds suspend_stats under
debugfs for users to check suspend to RAM statistics quickly.

If not using this patch, we have other methods to get info about
what device fails. One is to turn on  CONFIG_PM_DEBUG, but users
would get too much info and testers need recompile the system.

In addition, dynamic debug is another good tool to dump debug info.
But it still doesn't match our utilization scenario closely.
1) user need write a user space parser to process the syslog output;
2) Our testing scenario is we leave the mobile for at least hours.
   Then, check its status. No serial console available during the
   testing. One is because console would be suspended, and the other
   is serial console connecting with spi or HSU devices would consume
   power. These devices are powered off at suspend-2-ram.

Signed-off-by: ShuoX Liu <shuox.liu@intel.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-16 23:27:45 +02:00
Steven Rostedt
436fc28026 tracing: Fix returning of duplicate data after EOF in trace_pipe_raw
The trace_pipe_raw handler holds a cached page from the time the file
is opened to the time it is closed. The cached page is used to handle
the case of the user space buffer being smaller than what was read from
the ring buffer. The left over buffer is held in the cache so that the
next read will continue where the data left off.

After EOF is returned (no more data in the buffer), the index of
the cached page is set to zero. If a user app reads the page again
after EOF, the check in the buffer will see that the cached page
is less than page size and will return the cached page again. This
will cause reading the trace_pipe_raw again after EOF to return
duplicate data, making the output look like the time went backwards
but instead data is just repeated.

The fix is to not reset the index right after all data is read
from the cache, but to reset it after all data is read and more
data exists in the ring buffer.

Cc: stable <stable@kernel.org>
Reported-by: Jeremy Eder <jeder@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-10-14 10:44:25 -04:00
Geunsik Lim
9b5f8b31af ftrace: Fix README to state tracing_on to start/stop tracing
tracing_enabled option is deprecated.
To start/stop tracing, write to /sys/kernel/debug/tracing/tracing_on
without tracing_enabled. This patch is based on Linux 3.1.0-rc1

Signed-off-by: Geunsik Lim <geunsik.lim@samsung.com>
Link: http://lkml.kernel.org/r/1313127022-23830-1-git-send-email-leemgs1@gmail.com
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-10-14 10:41:33 -04:00
Ingo Molnar
910e94dd0c Merge branch 'tip/perf/core' of git://github.com/rostedt/linux into perf/core 2011-10-12 17:14:47 +02:00
Ingo Molnar
177e2163fe Merge branch 'tip/perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core 2011-10-12 09:07:49 +02:00
Steven Rostedt
d696b58ca2 tracing: Do not allocate buffer for trace_marker
When doing intense tracing, the kmalloc inside trace_marker can
introduce side effects to what is being traced.

As trace_marker() is used by userspace to inject data into the
kernel ring buffer, it needs to do so with the least amount
of intrusion to the operations of the kernel or the user space
application.

As the ring buffer is designed to write directly into the buffer
without the need to make a temporary buffer, and userspace already
went through the hassle of knowing how big the write will be,
we can simply pin the userspace pages and write the data directly
into the buffer. This improves the impact of tracing via trace_marker
tremendously!

Thanks to Peter Zijlstra and Thomas Gleixner for pointing out the
use of get_user_pages_fast() and kmap_atomic().

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Suggested-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-10-11 09:13:53 -04:00
Steven Rostedt
e0a413f619 tracing: Warn on output if the function tracer was found corrupted
As the function tracer is very intrusive, lots of self checks are
performed on the tracer and if something is found to be strange
it will shut itself down keeping it from corrupting the rest of the
kernel. This shutdown may still allow functions to be traced, as the
tracing only stops new modifications from happening. Trying to stop
the function tracer itself can cause more harm as it requires code
modification.

Although a WARN_ON() is executed, a user may not notice it. To help
the user see that something isn't right with the tracing of the system
a big warning is added to the output of the tracer that lets the user
know that their data may be incomplete.

Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-10-11 09:13:25 -04:00
Masami Hiramatsu
02ca1521ad ftrace/kprobes: Fix not to delete probes if in use
Fix kprobe-tracer not to delete a probe if the probe is in use.
In that case, delete operation will return -EBUSY.

This bug can cause a kernel panic if enabled probes are deleted
during perf record.

(Add some probes on functions)
sh-4.2# perf probe --del probe:\*
sh-4.2# exit
(kernel panic)

This is originally reported on the fedora bugzilla:

 https://bugzilla.redhat.com/show_bug.cgi?id=742383

I've also checked that this problem doesn't happen on
tracepoints when module removing because perf event
locks target module.

$ sudo ./perf record -e xfs:\* -aR sh
sh-4.2# rmmod xfs
ERROR: Module xfs is in use
sh-4.2# exit
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.203 MB perf.data (~8862 samples) ]

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: stable@kernel.org
Link: http://lkml.kernel.org/r/20111004104438.14591.6553.stgit@fedora15
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-10-10 15:13:03 -04:00
Rafael J. Wysocki
9696cc9007 Merge branch 'pm-qos' into pm-for-linus
* pm-qos:
  PM / QoS: Update Documentation for the pm_qos and dev_pm_qos frameworks
  PM / QoS: Add function dev_pm_qos_read_value() (v3)
  PM QoS: Add global notification mechanism for device constraints
  PM QoS: Implement per-device PM QoS constraints
  PM QoS: Generalize and export constraints management code
  PM QoS: Reorganize data structs
  PM QoS: Code reorganization
  PM QoS: Minor clean-ups
  PM QoS: Move and rename the implementation files
2011-10-07 23:17:07 +02:00
Rafael J. Wysocki
d727b60659 Merge branch 'pm-runtime' into pm-for-linus
* pm-runtime:
  PM / Tracing: build rpm-traces.c only if CONFIG_PM_RUNTIME is set
  PM / Runtime: Replace dev_dbg() with trace_rpm_*()
  PM / Runtime: Introduce trace points for tracing rpm_* functions
  PM / Runtime: Don't run callbacks under lock for power.irq_safe set
  USB: Add wakeup info to debugging messages
  PM / Runtime: pm_runtime_idle() can be called in atomic context
  PM / Runtime: Add macro to test for runtime PM events
  PM / Runtime: Add might_sleep() to runtime PM functions
2011-10-07 23:16:55 +02:00
David S. Miller
88c5100c28 Merge branch 'master' of github.com:davem330/net
Conflicts:
	net/batman-adv/soft-interface.c
2011-10-07 13:38:43 -04:00
Ingo Molnar
9d01402023 Merge commit 'v3.1-rc9' into perf/core
Merge reason: pick up latest fixes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-06 12:49:21 +02:00
Thomas Gleixner
510f5acc4f sched: Don't use tasklist_lock for debug prints
Avoid taking locks from debug prints, this avoids latencies on -rt,
and improves reliability of the debug code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-06 12:47:08 +02:00
Thomas Gleixner
1c83437e80 sched: Warn on rt throttling
The default rt-throttling is a source of never ending questions. Warn
once when we go into throttling so folks have that info in dmesg.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1110051331480.18778@ionos
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-06 12:47:04 +02:00
Peter Zijlstra
4939602a24 sched: Unify the ->cpus_allowed mask copy
Currently every sched_class::set_cpus_allowed() implementation has to
copy the cpumask into task_struct::cpus_allowed, this is pointless,
put this copy in the generic code.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/n/tip-jhl5s9fckd9ptw1fzbqqlrd3@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-06 12:47:00 +02:00
Peter Zijlstra
fa17b507f1 sched: Wrap scheduler p->cpus_allowed access
This task is preparatory for the migrate_disable() implementation, but
stands on its own and provides a cleanup.

It currently only converts those sites required for task-placement.
Kosaki-san once mentioned replacing cpus_allowed with a proper
cpumask_t instead of the NR_CPUS sized array it currently is, that
would also require something like this.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Link: http://lkml.kernel.org/n/tip-e42skvaddos99psip0vce41o@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-06 12:46:56 +02:00
Suresh Siddha
6eb57e0d65 sched: Request for idle balance during nohz idle load balance
rq's idle_at_tick is set to idle/busy during the timer tick
depending on the cpu was idle or not. This will be used later in the load
balance that will be done in the softirq context (which is a process
context in -RT kernels).

For nohz kernels, for the cpu doing nohz idle load balance on behalf of
all the idle cpu's, its rq->idle_at_tick might have a stale value (which is
recorded when it got the timer tick presumably when it is busy).

As the nohz idle load balancing is also being done at the same place
as the regular load balancing, nohz idle load balancing was bailing out
when it sees rq's idle_at_tick not set.

Thus leading to poor system utilization.

Rename rq's idle_at_tick to idle_balance and set it when someone requests
for nohz idle balance on an idle cpu.

Reported-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20111003220934.892350549@sbsiddha-desk.sc.intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-06 12:46:27 +02:00
Suresh Siddha
ca38062e57 sched: Use resched IPI to kick off the nohz idle balance
Current use of smp call function to kick the nohz idle balance can deadlock
in this scenario.

1. cpu-A did a generic_exec_single() to cpu-B and after queuing its call single
data (csd) to the call single queue, cpu-A took a timer interrupt.  Actual IPI
to cpu-B to process the call single queue is not yet sent.

2. As part of the timer interrupt handler, cpu-A decided to kick cpu-B
for the idle load balancing (sets cpu-B's rq->nohz_balance_kick to 1)
and __smp_call_function_single() with nowait will queue the csd to the
cpu-B's queue. But the generic_exec_single() won't send an IPI to cpu-B
as the call single queue was not empty.

3. cpu-A is busy with lot of interrupts

4. Meanwhile cpu-B is entering and exiting idle and noticed that it has
it's rq->nohz_balance_kick set to '1'. So it will go ahead and do the
idle load balancer and clear its rq->nohz_balance_kick.

5. At this point, csd queued as part of the step-2 above is still locked
and waiting to be serviced on cpu-B.

6. cpu-A is still busy with interrupt load and now it got another timer
interrupt and as part of it decided to kick cpu-B for another idle load
balancing (as it finds cpu-B's rq->nohz_balance_kick cleared in step-4
above) and does __smp_call_function_single() with the same csd that is
still locked.

7. And we get a deadlock waiting for the csd_lock() in the
__smp_call_function_single().

Main issue here is that cpu-B can service the idle load balancer kick
request from cpu-A even with out receiving the IPI and this lead to
doing multiple __smp_call_function_single() on the same csd leading to
deadlock.

To kick a cpu, scheduler already has the reschedule vector reserved. Use
that mechanism (kick_process()) instead of using the generic smp call function
mechanism to kick off the nohz idle load balancing and avoid the deadlock.

   [ This issue is present from 2.6.35+ kernels, but marking it -stable
     only from v3.0+ as the proposed fix depends on the scheduler_ipi()
     that is introduced recently. ]

Reported-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: stable@kernel.org # v3.0+
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20111003220934.834943260@sbsiddha-desk.sc.intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-06 12:46:23 +02:00
Thomas Gleixner
68cc3990a5 rtmutex: Add missing rcu_read_unlock() in debug_rt_mutex_print_deadlock()
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-10-05 13:20:24 +02:00
Thomas Gleixner
32cffdde4a genirq: Fix fatfinered fixup really
Putting the argument inside the quote does not really help.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-10-04 18:43:57 +02:00
Thomas Gleixner
908a328372 sched: Fix idle_cpu()
On -rt we observed hackbench waking all 400 tasks to a single cpu.
This is because of select_idle_sibling()'s interaction with the new
ipi based wakeup scheme.

The existing idle_cpu() test only checks to see if the current task on
that cpu is the idle task, it does not take already queued tasks into
account, nor does it take queued to be woken tasks into account.

If the remote wakeup IPIs come hard enough, there won't be time to
schedule away from the idle task, and would thus keep thinking the cpu
was in fact idle, regardless of the fact that there were already
several hundred tasks runnable.

We couldn't reproduce on mainline, but there's no reason it couldn't
happen.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-3o30p18b2paswpc9ohy2gltp@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-04 12:44:07 +02:00
Peter Zijlstra
fa14ff4acc sched: Convert to struct llist
Use the generic llist primitives.

We had a private lockless list implementation in the scheduler in the wake-list
code, now that we have a generic llist implementation that provides all required
operations, switch to it.

This patch is not expected to change any behavior.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1315836353.26517.42.camel@twins
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-04 12:43:58 +02:00
Peter Zijlstra
924f8f5af3 llist: Add llist_next()
So we don't have to expose the struct list_node member.

Cc: Huang Ying <ying.huang@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1315836348.26517.41.camel@twins
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-04 12:43:53 +02:00
Huang Ying
38aaf8090d irq_work: Use llist in the struct irq_work logic
Use llist in irq_work instead of the lock-less linked list
implementation in irq_work to avoid the code duplication.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1315461646-1379-6-git-send-email-ying.huang@intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-04 12:43:49 +02:00
Ingo Molnar
22f92bacbe Merge branch 'linus' into sched/core
Merge reason: pick up the latest fixes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-04 11:09:08 +02:00