Impact: fix to preempt trace triggering lockdep check_flag failure

In local_bh_disable, the use of add_preempt_count causes the
preempt tracer to start recording the time preemption is off.
But because it already modified the preempt_count to show
softirqs disabled, and before it called the lockdep code to
handle this, it causes a state that lockdep can not handle.

The preempt tracer will reset the ring buffer on start of a trace,
and the ring buffer reset code does a spin_lock_irqsave. This
calls into lockdep and lockdep will fail when it detects the
invalid state of having softirqs disabled but the internal
current->softirqs_enabled is still set.

The fix is to manually add the SOFTIRQ_OFFSET to preempt count
and call the preempt tracer code outside the lockdep critical
area.

Thanks to Peter Zijlstra for suggesting this solution.
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The logic in the tracing_start/stop code prevents the WARN_ON
from ever detecting if a start/stop pair was mismatched.
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup of duplicate features

The trace output disables the ring buffer and prevents tracing to
occur. The code in irqsoff to do the same thing is no longer needed.
This patch removes it.
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: fix bad times of recent resets

The ring buffer needs to reset its timestamps when reseting of the
buffer, otherwise the timestamps are stale and might be used to
calculate times in the buffer causing funny timestamps to appear.
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: better data for wakeup tracer

This patch adds the wakeup and schedule calls that are used by
the scheduler tracer to make the wakeup tracer more readable.
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: add option to trace all tasks or just RT tasks

The current wakeup tracer only traces RT task wakeups. This is
fine for those interested in wake up timings of RT tasks, but
it is useless for those that are interested in the causes
of long wakeups for non RT tasks.

This patch creates a "wakeup_rt" to implement the tracing of just
RT tasks (as the current "wakeup" does). And makes "wakeup" now
trace all tasks as an average developer would expect.
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

If the ring buffer recording has been disabled. Do not let
swapping of ring buffers occur. Simply return -EAGAIN.
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: fix to erased trace output

To try not to have the outputing of a trace interfere with the wakeup
tracer, it would disable tracing while the output was printing. But
if a trace had started when it was disabled, it can show a partial
trace. To try to solve this, on closing of the tracer, it would
clear the trace buffer.

The latency tracers (wakeup and irqsoff) have two buffers. One for
recording and one for holding the max trace that is printed. The
clearing of the trace above should only affect the recording buffer.
But for some reason it would move the erased trace to the print
buffer. Probably due to a race with the closing of the trace and
the saving ofhe max race.

The above is all pretty useless, and if the user does not want the
printing of the trace to be traced itself, then the user can manual
disable tracing. This patch removes all the code that tries to keep
the output of the tracer from modifying the trace.
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: use percpu data instead of a global structure

Use:

   static DEFINE_PER_CPU(struct workqueue_global_stats, all_workqueue_stat);

instead of allocating a global structure.

percpu data also works well on NUMA.
Signed-off-by: NLai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Cleanup the cpuid check for DS configuration.
Signed-off-by: NMarkus Metzger <markus.t.metzger@intel.com>
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Document the hw-branch-tracer in the ftrace documentation.
Signed-off-by: NMarkus Metzger <markus.t.metzger@intel.com>
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Change the hw-branch-tracer format to be more readable.
Signed-off-by: NMarkus Metzger <markus.t.metzger@intel.com>
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Reset the ftrace buffer on close. Since we use cyclic buffers, the
trace is not contiguous, anyway.
Signed-off-by: NMarkus Metzger <markus.t.metzger@intel.com>
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Dump the branch trace on an oops (based on ftrace_dump_on_oops).
Signed-off-by: NMarkus Metzger <markus.t.metzger@intel.com>
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Support hotplug cpus.
Reported-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NMarkus Metzger <markus.t.metzger@intel.com>
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: fix failure of dynamic function tracer selftest

In a course of development, a developer does several makes on their
kernel. Sometimes, the make might do something abnormal. In the
case of running the recordmcount.pl script on an object twice,
the script will duplicate all the calls to mcount in the __mcount_loc
section.

On boot up, the dynamic function tracer is careful when it modifies
code, and performs several consistency checks. One is to not modify
the call site if it is not what it expects it to be. If a function
call site is listed twice, the first entry will convert the site
to a nop, and the second will fail because it expected to see a
call to mcount, but instead it sees a nop. Thus, the function tracer
is disabled.

Eric Sesterhenn reported seeing:

[    1.055440] ftrace: converting mcount calls to 0f 1f 44 00 00
[    1.055568] ftrace: allocating 29418 entries in 116 pages
[    1.061000] ------------[ cut here ]------------
[    1.061000] WARNING: at kernel/trace/ftrace.c:441

 [...]

[    1.060000] ---[ end trace 4eaa2a86a8e2da23 ]---
[    1.060000] ftrace failed to modify [<c0118072>] check_corruption+0x3/0x2d
[    1.060000]  actual: 0f:1f:44:00:00

This warning shows that check_corruption+0x3 already had a nop in
its place (0x0f1f440000). After compiling another kernel the problem
went away.

Later Eric Paris notice the same type of issue. Luckily, he saved
the vmlinux file that caused it. In the file we found a bunch of
duplicate mcount call site records, which lead us to the script.

Perhaps this problem only happens to people named Eric.

This patch changes the script to test if the __mcount_loc already
exists in the object file, and if it does, it will print out
an error message and kill the compile.
Reported-by: NEric Sesterhenn <snakebyte@gmx.de>
Reported-by: NEric Paris <eparis@redhat.com>
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (23 commits)
  ACPI PCI hotplug: harden against panic regression
  ACPI: rename main.c to sleep.c
  dell-laptop: move to drivers/platform/x86/ from drivers/misc/
  eeepc-laptop: enable Bluetooth ACPI details
  ACPI: fix ACPI_FADT_S4_RTC_WAKE comment
  kprobes: check CONFIG_FREEZER instead of CONFIG_PM
  PM: Fix freezer compilation if PM_SLEEP is unset
  thermal fixup for broken BIOS which has invalid trip points.
  ACPI: EC: Don't trust ECDT tables from ASUS
  ACPI: EC: Limit workaround for ASUS notebooks even more
  ACPI: thinkpad-acpi: bump up version to 0.22
  ACPI: thinkpad-acpi: handle HKEY event 6030
  ACPI: thinkpad-acpi: clean-up fan subdriver quirk
  ACPI: thinkpad-acpi: start the event hunt season
  ACPI: thinkpad-acpi: handle HKEY thermal and battery alarms
  ACPI: thinkpad-acpi: clean up hotkey_notify()
  ACPI: thinkpad-acpi: use killable instead of interruptible mutexes
  ACPI: thinkpad-acpi: add UWB radio support
  ACPI: thinkpad-acpi: preserve radio state across shutdown
  ACPI: thinkpad-acpi: resume with radios disabled
  ...

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
  netxen: include ipv6.h (fixes build failure)
  netxen: avoid invalid iounmap

ACPI hotplug panic with current git head
http://lkml.org/lkml/2009/1/10/136

Rather than reverting the entire commit that causes the crash:
e8c331e9
"PCI hotplug: introduce functions for ACPI slot detection"

simply harden against it while the changes to
the hotplug code on this particularl machine are understood.
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

Signed-off-by: NLen Brown <len.brown@intel.com>

Signed-off-by: NLen Brown <len.brown@intel.com>

Although rfkill support for the EEE bluetooth device has been added to
2.6.28-rc the appropriate ACPI accessor definitions were not added, so
the support was non functional. The patch below adds the get and set
accessors and has been verified to work on an EEE 901.
Signed-off-by: NJonathan McDowell <noodles@earth.li>
Acked-by: NMatthew Garrett <mjg@redhat.com>
Acked-by: NCorentin Chary <corentincj@iksaif.net>
Signed-off-by: NLen Brown <len.brown@intel.com>

Make the comment for ACPI_FADT_S4_RTC_WAKE match the ACPI spec;
that bit has nothing to do with status bits.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

Check CONFIG_FREEZER instead of CONFIG_PM because kprobe booster
depends on freeze_processes() and thaw_processes() when CONFIG_PREEMPT=y.

This fixes a linkage error which occurs when CONFIG_PREEMPT=y, CONFIG_PM=y
and CONFIG_FREEZER=n.
Reported-by: NCheng Renquan <crquan@gmail.com>
Signed-off-by: NMasami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NLen Brown <len.brown@intel.com>

Freezer fails to compile if with the following configuration
settings:

CONFIG_CGROUPS=y
CONFIG_CGROUP_FREEZER=y
CONFIG_MODULES=y
CONFIG_FREEZER=y
CONFIG_PM=y
CONFIG_PM_SLEEP=n

Fix this by making process.o compilation depend on CONFIG_FREEZER.
Reported-by: NCheng Renquan <crquan@gmail.com>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NPavel Machek <pavel@suse.cz>
Signed-off-by: NLen Brown <len.brown@intel.com>

ACPI thermal driver only re-evaluate VALID trip points.

For the broken BIOS show in
http://bugzilla.kernel.org/show_bug.cgi?id=8544
the active[0] is set to invalid at boot time
and it will not be re-evaluated again.
We can still get a single warning message at boot time.

http://marc.info/?l=linux-kernel&m=120496222629983&w=2

http://bugzilla.kernel.org/show_bug.cgi?id=12203

Signed-off-by: Zhang Rui<rui.zhang@intel.com>
Tested-by: NMárton Németh <nm127@freemail.hu>
Signed-off-by: NLen Brown <len.brown@intel.com>

Fixes a build error in absence of CONFIG_IPV6:

drivers/net/netxen/netxen_nic_main.c:1189: error: implicit declaration of function 'ipv6_hdr'
drivers/net/netxen/netxen_nic_main.c:1189: error: invalid type argument of '->'
Reported-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NDhananjay Phadke <dhananjay@netxen.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

http://bugzilla.kernel.org/show_bug.cgi?id=9399
http://bugzilla.kernel.org/show_bug.cgi?id=11880Signed-off-by: NAlexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: NLen Brown <len.brown@intel.com>

For NX3031 only one I/O range is mapped, so unmapping other
two which are used by older chips, causes this warning on
ppc64.

"Attempt to iounmap early bolted mapping at 0x0000000000000000"
Signed-off-by: NDhananjay Phadke <dhananjay@netxen.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

References: http://bugzilla.kernel.org/show_bug.cgi?id=11884Signed-off-by: NAlexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: NLen Brown <len.brown@intel.com>

* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: fix ioctl arg size (userland incompatible change!)
  Btrfs: Clear the device->running_pending flag before bailing on congestion

The structure used to send device in btrfs ioctl calls was not
properly aligned, and so 32 bit ioctls would not work properly on
64 bit kernels.

We could fix this with compat ioctls, but we're just one byte away
and it doesn't make sense at this stage to carry about the compat ioctls
forever at this stage in the project.

This patch brings the ioctl arg up to an evenly aligned 4k.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Btrfs maintains a queue of async bio submissions so the checksumming
threads don't have to wait on get_request_wait.  In order to avoid
extra wakeups, this code has a running_pending flag that is used
to tell new submissions they don't need to wake the thread.

When the threads notice congestion on a single device, they
may decide to requeue the job and move on to other devices.  This
makes sure the running_pending flag is cleared before the
job is requeued.

It should help avoid IO stalls by making sure the task is woken up
when new submissions come in.
Signed-off-by: NChris Mason <chris.mason@oracle.com>