sched: Fix select_idle_sibling()

commit 8b911acdf08477c059d1c36c21113ab1696c612b upstream

Don't bother with selection when the current cpu is idle.  Recent load
balancing changes also make it no longer necessary to check wake_affine()
success before returning the selected sibling, so we now always use it.

Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1268301369.6785.36.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
sched: Pre-compute cpumask_weight(sched_domain_span(sd))

commit 669c55e9f99b90e46eaa0f98a67ec53d46dc969a upstream

Dave reported that his large SPARC machines spend lots of time in
hweight64(), try and optimize some of those needless cpumask_weight()
invocations (esp. with the large offstack cpumasks these are very
expensive indeed).

Reported-by: David Miller <davem@davemloft.net>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
sched: Fix select_idle_sibling() logic in select_task_rq_fair()

commit 99bd5e2f245d8cd17d040c82d40becdb3efd9b69 upstream

Issues in the current select_idle_sibling() logic in select_task_rq_fair()
in the context of a task wake-up:

a) Once we select the idle sibling, we use that domain (spanning the cpu that
   the task is currently woken-up and the idle sibling that we found) in our
   wake_affine() decisions. This domain is completely different from the
   domain(we are supposed to use) that spans the cpu that the task currently
   woken-up and the cpu where the task previously ran.

b) We do select_idle_sibling() check only for the cpu that the task is
   currently woken-up on. If select_task_rq_fair() selects the previously run
   cpu for waking the task, doing a select_idle_sibling() check
   for that cpu also helps and we don't do this currently.

c) In the scenarios where the cpu that the task is woken-up is busy but
   with its HT siblings are idle, we are selecting the task be woken-up
   on the idle HT sibling instead of a core that it previously ran
   and currently completely idle. i.e., we are not taking decisions based on
   wake_affine() but directly selecting an idle sibling that can cause
   an imbalance at the SMT/MC level which will be later corrected by the
   periodic load balancer.

Fix this by first going through the load imbalance calculations using
wake_affine() and once we make a decision of woken-up cpu vs previously-ran cpu,
then choose a possible idle sibling for waking up the task on.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1270079265.7835.8.camel@sbs-t61.sc.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
sched: cpuacct: Use bigger percpu counter batch values for stats counters

commit fa535a77bd3fa32b9215ba375d6a202fe73e1dd6 upstream

When CONFIG_VIRT_CPU_ACCOUNTING and CONFIG_CGROUP_CPUACCT are
enabled we can call cpuacct_update_stats with values much larger
than percpu_counter_batch.  This means the call to
percpu_counter_add will always add to the global count which is
protected by a spinlock and we end up with a global spinlock in
the scheduler.

Based on an idea by KOSAKI Motohiro, this patch scales the batch
value by cputime_one_jiffy such that we have the same batch
limit as we would if CONFIG_VIRT_CPU_ACCOUNTING was disabled.
His patch did this once at boot but that initialisation happened
too early on PowerPC (before time_init) and it was never updated
at runtime as a result of a hotplug cpu add/remove.

This patch instead scales percpu_counter_batch by
cputime_one_jiffy at runtime, which keeps the batch correct even
after cpu hotplug operations.  We cap it at INT_MAX in case of
overflow.

For architectures that do not support
CONFIG_VIRT_CPU_ACCOUNTING, cputime_one_jiffy is the constant 1
and gcc is smart enough to optimise min(s32
percpu_counter_batch, INT_MAX) to just percpu_counter_batch at
least on x86 and PowerPC.  So there is no need to add an #ifdef.

On a 64 thread PowerPC box with CONFIG_VIRT_CPU_ACCOUNTING and
CONFIG_CGROUP_CPUACCT enabled, a context switch microbenchmark
is 234x faster and almost matches a CONFIG_CGROUP_CPUACCT
disabled kernel:

 CONFIG_CGROUP_CPUACCT disabled:   16906698 ctx switches/sec
 CONFIG_CGROUP_CPUACCT enabled:       61720 ctx switches/sec
 CONFIG_CGROUP_CPUACCT + patch:	   16663217 ctx switches/sec

Tested with:

 wget http://ozlabs.org/~anton/junkcode/context_switch.c
 make context_switch
 for i in `seq 0 63`; do taskset -c $i ./context_switch & done
 vmstat 1

Signed-off-by: Anton Blanchard <anton@samba.org>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Tested-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
ALSA: hda - Handle missing NID 0x1b on ALC259 codec

commit 5d4abf93ea3192cc666430225a29a4978c97c57d upstream.

Since ALC259/269 use the same parser of ALC268, the pin 0x1b was ignored
as an invalid widget.  Just add this NID to handle properly.
This will add the missing mixer controls for some devices.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Cc: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
ALSA: hda - Handle pin NID 0x1a on ALC259/269

commit b08b1637ce1c0196970348bcabf40f04b6b3d58e upstream.

The pin NID 0x1a should be handled as well as NID 0x1b.
Also added comments.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Cc: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
hwmon: (f75375s) Shift control mode to the correct bit position

commit 96f3640894012be7dd15a384566bfdc18297bc6c upstream.

The spec notes that fan0 and fan1 control mode bits are located in bits
7-6 and 5-4 respectively, but the FAN_CTRL_MODE macro was making the
bits shift by 5 instead of by 4.

Signed-off-by: Guillem Jover <guillem@hadrons.org>
Cc: Riku Voipio <riku.voipio@iki.fi>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
hwmon: (f75375s) Do not overwrite values read from registers

commit c3b327d60bbba3f5ff8fd87d1efc0e95eb6c121b upstream.

All bits in the values read from registers to be used for the next
write were getting overwritten, avoid doing so to not mess with the
current configuration.

Signed-off-by: Guillem Jover <guillem@hadrons.org>
Cc: Riku Voipio <riku.voipio@iki.fi>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
apm_power: Add missing break statement

commit 1d220334d6a8a711149234dc5f98d34ae02226b8 upstream.

The missing break statement causes wrong capacity calculation for
batteries that report energy.

Reported-by: d binderman <dcb314@hotmail.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
NFS: Fix a typo in nfs_sockaddr_match_ipaddr6

commit b20d37ca9561711c6a3c4b859c2855f49565e061 upstream.

Reported-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
SUNRPC: Fix race corrupting rpc upcall

commit 5a67657a2e90c9e4a48518f95d4ba7777aa20fbb upstream.

If rpc_queue_upcall() adds a new upcall to the rpci->pipe list just
after rpc_pipe_release calls rpc_purge_list(), but before it calls
gss_pipe_release (as rpci->ops->release_pipe(inode)), then the latter
will free a message without deleting it from the rpci->pipe list.

We will be left with a freed object on the rpc->pipe list.  Most
frequent symptoms are kernel crashes in rpc.gssd system calls on the
pipe in question.

Reported-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
i915: return -EFAULT if copy_to_user fails

commit 9927a403ca8c97798129953fa9cbb5dc259c7cb9 upstream.

copy_to_user returns the number of bytes remaining to be copied, but we
want to return a negative error code here.  These are returned to
userspace.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
i915_gem: return -EFAULT if copy_to_user fails

commit c877cdce93a44eea96f6cf7fc04be7d0372db2be upstream.

copy_to_user() returns the number of bytes remaining to be copied and
I'm pretty sure we want to return a negative error code here.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drm/i915: Prevent double dpms on

commit 032d2a0d068b0368296a56469761394ef03207c3 upstream.

Arguably this is a bug in drm-core in that we should not be called twice
in succession with DPMS_ON, however this is still occuring and we see
FDI link training failures on the second call leading to the occassional
blank display. For the time being ignore the repeated call.

Original patch by Dave Airlie <airlied@redhat.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drm: Only decouple the old_fb from the crtc is we call mode_set*

commit 356ad3cd616185631235ffb48b3efbf39f9923b3 upstream.

Otherwise when disabling the output we switch to the new fb (which is
likely NULL) and skip the call to mode_set -- leaking driver private
state on the old_fb.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=29857
Reported-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dave Airlie <airlied@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Linux 2.6.32.22