Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends.  That changed
when we forked out support for the latter into the export.h file.

This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.  The advantage
in doing so is that module.h itself sources about 15 other headers;
adding significantly to what we feed cpp, and it can obscure what
headers we are effectively using.

Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each obj-y/bool instance
for the presence of either and replace as needed.  Build testing
revealed some implicit header usage that was fixed up accordingly.

Note that some bool/obj-y instances remain since module.h is
the header for some exception table entry stuff, and for things
like __init_or_module (code that is tossed when MODULES=n).
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160714001901.31603-4-paul.gortmaker@windriver.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

The following patch adds perf_event support for the Xeon-Phi
PMU, as documented in the "Intel Xeon Phi Coprocessor (codename:
Knights Corner) Performance Monitoring Units" manual.

Even though it is a co-processor, a Phi runs a full Linux
environment and can support performance counters.

This is just barebones support, it does not add support for
interesting new features such as the SPFLT intruction that
allows starting/stopping events without entering the kernel.

The PMU internally is just like that of an original Pentium, but
a "P6-like" MSR interface is provided.  The interface is
different enough from a real P6 that it's not easy (or
practical) to re-use the code in  perf_event_p6.c
Acked-by: NLawrence F Meadows <lawrence.f.meadows@intel.com>
Acked-by: NCyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: NVince Weaver <vincent.weaver@maine.edu>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: eranian@gmail.com
Cc: Lawrence F <lawrence.f.meadows@intel.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1209261405320.8398@vincent-weaver-1.um.maine.eduSigned-off-by: NIngo Molnar <mingo@kernel.org>

This patch allows the reservation of perfctrs with new msr addresses
introduced for AMD cpu family 15h (0xc0010200/0xc0010201, etc).
Signed-off-by: NRobert Richter <robert.richter@amd.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1296664860-10886-4-git-send-email-robert.richter@amd.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The x86 arch has shifted its use of the nmi_watchdog from a
local implementation to the global one provide by
kernel/watchdog.c.  This shift has caused a whole bunch of
compile problems under different config options.  I attempt to
simplify things with the patch below.

In order to simplify things, I had to come to terms with the
meaning of two terms ARCH_HAS_NMI_WATCHDOG and
CONFIG_HARDLOCKUP_DETECTOR.  Basically they mean the same thing,
the former on a local level and the latter on a global level.

With the old x86 nmi watchdog gone, there is no need to rely on
defining the ARCH_HAS_NMI_WATCHDOG variable because it doesn't
make sense any more.  x86 will now use the global
implementation.

The changes below do a few things.  First it changes the few
places that relied on ARCH_HAS_NMI_WATCHDOG to use
CONFIG_X86_LOCAL_APIC (the former was an alias for the latter
anyway, so nothing unusual here).  Those pieces of code were
relying more on local apic functionality the nmi watchdog
functionality, so the change should make sense.

Second, I removed the x86 implementation of
touch_nmi_watchdog().  It isn't need now, instead x86 will rely
on kernel/watchdog.c's implementation.

Third, I removed the #define ARCH_HAS_NMI_WATCHDOG itself from
x86.  And tweaked the include/linux/nmi.h file to tell users to
look for an externally defined touch_nmi_watchdog in the case of
ARCH_HAS_NMI_WATCHDOG _or_ CONFIG_HARDLOCKUP_DETECTOR. This
changes removes some of the ugliness in that file.

Finally, I added a Kconfig dependency for
CONFIG_HARDLOCKUP_DETECTOR that said you can't have
ARCH_HAS_NMI_WATCHDOG _and_ CONFIG_HARDLOCKUP_DETECTOR.  You can
only have one nmi_watchdog.

Tested with
ARCH=i386: allnoconfig, defconfig, allyesconfig, (various broken
configs) ARCH=x86_64: allnoconfig, defconfig, allyesconfig,
(various broken configs)

Hopefully, after this patch I won't get any more compile broken
emails. :-)

v3:
  changed a couple of 'linux/nmi.h' -> 'asm/nmi.h' to pick-up correct function
  prototypes when CONFIG_HARDLOCKUP_DETECTOR is not set.
Signed-off-by: NDon Zickus <dzickus@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: fweisbec@gmail.com
LKML-Reference: <1293044403-14117-1-git-send-email-dzickus@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Now that the bulk of the old nmi_watchdog is gone, remove all
the stub variables and hooks associated with it.

This touches lots of files mainly because of how the io_apic
nmi_watchdog was implemented.  Now that the io_apic nmi_watchdog
is forever gone, remove all its fingers.

Most of this code was not being exercised by virtue of
nmi_watchdog != NMI_IO_APIC, so there shouldn't be anything to
risky here.
Signed-off-by: NDon Zickus <dzickus@redhat.com>
Cc: fweisbec@gmail.com
Cc: gorcunov@openvz.org
LKML-Reference: <1289578944-28564-3-git-send-email-dzickus@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

CPU families 0x12, 0x14 and 0x15 support this functionality.
Signed-off-by: NAndreas Herrmann <andreas.herrmann3@amd.com>
LKML-Reference: <20100930123357.GC20545@loge.amd.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

For consistency reasons this patch renames
ARCH_PERFMON_EVENTSEL0_ENABLE to ARCH_PERFMON_EVENTSEL_ENABLE.

The following is performed:

 $ sed -i -e s/ARCH_PERFMON_EVENTSEL0_ENABLE/ARCH_PERFMON_EVENTSEL_ENABLE/g \
   arch/x86/include/asm/perf_event.h arch/x86/kernel/cpu/perf_event.c \
   arch/x86/kernel/cpu/perf_event_p6.c \
   arch/x86/kernel/cpu/perfctr-watchdog.c \
   arch/x86/oprofile/op_model_amd.c arch/x86/oprofile/op_model_ppro.c
Signed-off-by: NRobert Richter <robert.richter@amd.com>

avail_to_resrv_perfctr_nmi() is neither EXPORT'd, nor used in
the file. So remove it.
Signed-off-by: NNaga Chumbalkar <nagananda.chumbalkar@hp.com>
Acked-by: NCyrill Gorcunov <gorcunov@gmail.com>
Cc: oprofile-list@lists.sf.net
LKML-Reference: <20091224015441.6005.4408.sendpatchset@localhost.localdomain>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The x86 lapic nmi watchdog does not recognize AMD Family 11h,
resulting in:

  NMI watchdog: CPU not supported

As far as I can see from available documentation (the BKDM),
family 11h looks identical to family 10h as far as the PMU
is concerned.

Extending the check to accept family 11h results in:

  Testing NMI watchdog ... OK.

I've been running with this change on a Turion X2 Ultra ZM-82
laptop for a couple of weeks now without problems.
Signed-off-by: NMikael Pettersson <mikpe@it.uu.se>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Cc: <stable@kernel.org>
LKML-Reference: <19223.53436.931768.278021@pilspetsen.it.uu.se>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Bye-bye Performance Counters, welcome Performance Events!

In the past few months the perfcounters subsystem has grown out its
initial role of counting hardware events, and has become (and is
becoming) a much broader generic event enumeration, reporting, logging,
monitoring, analysis facility.

Naming its core object 'perf_counter' and naming the subsystem
'perfcounters' has become more and more of a misnomer. With pending
code like hw-breakpoints support the 'counter' name is less and
less appropriate.

All in one, we've decided to rename the subsystem to 'performance
events' and to propagate this rename through all fields, variables
and API names. (in an ABI compatible fashion)

The word 'event' is also a bit shorter than 'counter' - which makes
it slightly more convenient to write/handle as well.

Thanks goes to Stephane Eranian who first observed this misnomer and
suggested a rename.

User-space tooling and ABI compatibility is not affected - this patch
should be function-invariant. (Also, defconfigs were not touched to
keep the size down.)

This patch has been generated via the following script:

  FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')

  sed -i \
    -e 's/PERF_EVENT_/PERF_RECORD_/g' \
    -e 's/PERF_COUNTER/PERF_EVENT/g' \
    -e 's/perf_counter/perf_event/g' \
    -e 's/nb_counters/nb_events/g' \
    -e 's/swcounter/swevent/g' \
    -e 's/tpcounter_event/tp_event/g' \
    $FILES

  for N in $(find . -name perf_counter.[ch]); do
    M=$(echo $N | sed 's/perf_counter/perf_event/g')
    mv $N $M
  done

  FILES=$(find . -name perf_event.*)

  sed -i \
    -e 's/COUNTER_MASK/REG_MASK/g' \
    -e 's/COUNTER/EVENT/g' \
    -e 's/\<event\>/event_id/g' \
    -e 's/counter/event/g' \
    -e 's/Counter/Event/g' \
    $FILES

... to keep it as correct as possible. This script can also be
used by anyone who has pending perfcounters patches - it converts
a Linux kernel tree over to the new naming. We tried to time this
change to the point in time where the amount of pending patches
is the smallest: the end of the merge window.

Namespace clashes were fixed up in a preparatory patch - and some
stylistic fallout will be fixed up in a subsequent patch.

( NOTE: 'counters' are still the proper terminology when we deal
  with hardware registers - and these sed scripts are a bit
  over-eager in renaming them. I've undone some of that, but
  in case there's something left where 'counter' would be
  better than 'event' we can undo that on an individual basis
  instead of touching an otherwise nicely automated patch. )
Suggested-by: NStephane Eranian <eranian@google.com>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: NPaul Mackerras <paulus@samba.org>
Reviewed-by: NArjan van de Ven <arjan@linux.intel.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <linux-arch@vger.kernel.org>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

No code changes except printk levels (although some of the K6
mtrr code might be clearer if there were a few as would
splitting out some of the intel cache code).
Signed-off-by: NAlan Cox <alan@linux.intel.com>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

lapic_watchdog_ok() is a global function but no one is using it.
Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1246554335.2242.29.camel@jaswinder.satnam>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Expand Intel NMI perfctr1 workaround to include a Core2 processor stepping
(cpuid family-6, model-f, stepping-4).  Resolves a situation where the NMI
would not enable on these processors.
Signed-off-by: NPrarit Bhargava <prarit@redhat.com>
Acked-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Cc: prarit@redhat.com
Cc: suresh.b.siddha@intel.com
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

make it simpler, don't need have one extra struct.

v2: fix the sgi_uv build
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: rename include file

We'll be providing an asm/perf_counter.h to the generic perfcounter code,
so use the already existing x86 file for this purpose and rename it.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

it can be called in the NMI path:

[    0.645999] calling  ftrace_dynamic_init+0x0/0xd6
[    0.647521] ------------[ cut here ]------------
[    0.647521] WARNING: at kernel/trace/ftrace.c:348 ftrace_record_ip+0x4e/0x252()
[    0.647521] Modules linked in:
[    0.647521] Pid: 15, comm: kstop1 Not tainted 2.6.27-rc1-tip #22686
[    0.647521]
[    0.647521] Call Trace:
[    0.647521]  <NMI>  [<ffffffff8024593f>] warn_on_slowpath+0x5d/0x84
[    0.647521]  [<ffffffff80220b99>] ? lapic_wd_event+0xb/0x5c
[    0.647521]  [<ffffffff80287b3b>] ftrace_record_ip+0x4e/0x252
[    0.647521]  [<ffffffff80211274>] mcount_call+0x5/0x31
[    0.647521]  [<ffffffff80220b9e>] ? lapic_wd_event+0x10/0x5c
[    0.647521]  [<ffffffff8083f3ec>] nmi_watchdog_tick+0x19d/0x1ad
[    0.647521]  [<ffffffff8083e875>] default_do_nmi+0x75/0x1e3
[    0.647521]  [<ffffffff8083f0b3>] do_nmi+0x5d/0x94
[    0.647521]  [<ffffffff8083e2d2>] nmi+0xa2/0xc2
[    0.647521]  [<ffffffff802b48c3>] ? check_bytes_and_report+0x11/0xcc
[    0.647521]  <<EOE>>  [<ffffffff80211274>] ? mcount_call+0x5/0x31
[    0.647521]  [<ffffffff802b49df>] check_object+0x61/0x1b0
[    0.647521]  [<ffffffff802b502a>] __slab_free+0x169/0x2ae
[    0.647521]  [<ffffffff80242dbf>] ? __cleanup_sighand+0x25/0x27
[    0.647521]  [<ffffffff80242dbf>] ? __cleanup_sighand+0x25/0x27
[    0.647521]  [<ffffffff802b60cd>] kmem_cache_free+0x85/0xb9
[    0.647521]  [<ffffffff80242dbf>] __cleanup_sighand+0x25/0x27
[    0.647521]  [<ffffffff80247b3d>] release_task+0x256/0x339
[    0.647521]  [<ffffffff802490b4>] do_exit+0x764/0x7ef
[    0.647521]  [<ffffffff8027624c>] __xchg+0x0/0x38
[    0.647521]  [<ffffffff8027619a>] ? stop_cpu+0x0/0xb2
[    0.647521]  [<ffffffff8027619a>] ? stop_cpu+0x0/0xb2
[    0.647521]  [<ffffffff8025922f>] kthread+0x4e/0x7b
[    0.647521]  [<ffffffff80212979>] child_rip+0xa/0x11
[    0.647521]  [<ffffffff80211c17>] ? restore_args+0x0/0x30
[    0.647521]  [<ffffffff802283a5>] ? native_load_tls+0x14/0x2e
[    0.647521]  [<ffffffff802591e1>] ? kthread+0x0/0x7b
[    0.647521]  [<ffffffff8021296f>] ? child_rip+0x0/0x11
[    0.647521]
[    0.647521] ---[ end trace 4eaa2a86a8e2da22 ]---
[    0.672032] initcall ftrace_dynamic_init+0x0/0xd6 returned 0 after 19 msecs

also mark it no-kprobes while at it.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

There's a small window when NMI watchdog is being set up that if any NMIs
are triggered, the NMI code will make make use of not initalized wd_ops
elements:
	void setup_apic_nmi_watchdog(void *unused)
	{
		if (__get_cpu_var(wd_enabled))
			return;

		/* cheap hack to support suspend/resume */
		/* if cpu0 is not active neither should the other cpus */
		if (smp_processor_id() != 0 && atomic_read(&nmi_active) <= 0)
			return;

		switch (nmi_watchdog) {
		case NMI_LOCAL_APIC:
			/* enable it before to avoid race with handler */
-->			__get_cpu_var(wd_enabled) = 1;
-->			if (lapic_watchdog_init(nmi_hz) < 0) {
(...)
	asmlinkage notrace __kprobes void default_do_nmi(struct pt_regs *regs)
	{
	(...)
			if (nmi_watchdog_tick(regs, reason))
				return;
(...)
	notrace __kprobes int
	nmi_watchdog_tick(struct pt_regs *regs, unsigned reason)
	{
	(...)
		if (!__get_cpu_var(wd_enabled))
			return rc;
		switch (nmi_watchdog) {
		case NMI_LOCAL_APIC:
			rc |= lapic_wd_event(nmi_hz);
(...)
int lapic_wd_event(unsigned nmi_hz)
{
	struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);
	u64 ctr;

-->	rdmsrl(wd->perfctr_msr, ctr);

and wd->*_msr will be initialized on each processor type specific setup, after
enabling NMIs for PMIs. Since the counter was just set, the chances of an
performance counter generated NMI is minimal, but any other unknown NMI would
trigger the problem. This patch fixes the problem by setting everything up
before enabling performance counter generated NMIs and will set wd_enabled
using a callback function.
Signed-off-by: NAristeu Rozanski <aris@redhat.com>
Acked-by: NDon Zickus <dzickus@redhat.com>
Acked-by: NPrarit Bhargava <prarit@redhat.com>
Acked-by: NVivek Goyal <vgoyal@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

P4s have a quirk that makes necessary to clear P4_CCCR_OVF bit on the CCCR
everytime the PMI is triggered. When booting the kernel with reset_devices
(more specific kdump case), the counters reach zero and the PMI will be
generated. This is not a problem on other processors but on P4s, it'll
continue to generate NMIs until that bit is cleared. Since there may be
other users of the performance counters, clear and disable all of them
when booting with reset_devices option.

We have a P4 box here that crashes because of this problem. Since the kdump
kernel usually boots with only one processor active, the second logical
unit won't be set up, therefore, MSR_P4_IQ_CCCR1 (and other performance
counter registers) won't be cleared and P4_CCCR_OVF may be still set because
the previous kernel was using this register. An NMI is triggered because of
the MSR_P4_IQ_CCCR1 right after the NMI delivery is enabled, triggering the
race fixed on my previous email.
Signed-off-by: NAristeu Rozanski <aris@redhat.com>
Acked-by: NDon Zickus <dzickus@redhat.com>
Acked-by: NPrarit Bhargava <prarit@redhat.com>
Acked-by: NVivek Goyal <vgoyal@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Currently, setup_p4_watchdog() use CCCR_OVF_PMI1 to enable the counter
overflow interrupts to the second logical core. But this bit doesn't work
on Pentium 4 Ds (model 4, stepping 4) and this patch avoids its use on
these processors. Tested on 4 different machines that have this
specific model with success.
Signed-off-by: NAristeu Rozanski <aris@redhat.com>
Cc: jvillalovos@redhat.com
Signed-off-by: NIngo Molnar <mingo@elte.hu>

There are a couple of places where (P)Dprintk is used which is an old
compile time enabled printk wrapper. Convert it to the generic
pr_debug().
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Just some code beautification. Nothing else.
Signed-off-by: NCyrill Gorcunov <gorcunov@gmail.com>
Cc: macro@linux-mips.org
Signed-off-by: NIngo Molnar <mingo@elte.hu>

It's not even passed on to smp_call_function() anymore, since that
was removed. So kill it.
Acked-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Reviewed-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

This patch does check if CPU is being recongnized
before call the unreserve(). Since enable_lapic_nmi_watchdog()
does have such a check the same is make sense here too
in a sake of code consistency (but nothing more).
Signed-off-by: NCyrill Gorcunov <gorcunov@gmail.com>
Cc: mingo@redhat.com
Cc: hpa@zytor.com
Cc: macro@linux-mips.org
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

There apparently was an unnoticed conflict between an earlier patch to
this file and mine (d1e08474), which
I noticed only now. I suppose a change like the one below (untested) is
needed; I didn't get any response on a confirmation request for this from
the submitter of the first patch.

The issue is the writing of the 'checkbit' member at the end of
setup_intel_arch_watchdog(), which my patch made go to intel_arch_wd_ops
rather than wd_ops.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

right now if there's no CPU support for nmi_watchdog=2 we'll just
refuse it silently.

print a useful warning.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

implement nmi_watchdog=2 on this class of CPUs:

  cpu family      : 15
  model           : 6
  model name      : Intel(R) Pentium(R) D CPU 3.00GHz

the watchdog's ->setup() method is safe anyway, so if the CPU
cannot support it we'll bail out safely.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Here is a small patch to change the behavior of the PMU msr allocator
to avoid BUG_ON() when the MSR is unknwon. Instead, it now returns
ok, which means "I do not manage". The current allocator is not
yet managing the full set of PMU registers (e.g., GLOBAL_* on Core 2).

[watchdog] do not BUG_ON() in the MSR allocator if MSR is unknown, return ok
instead
Signed-off-by: NStephane Eranian <eranian@hpl.hp.com>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

.. as they're, with a single exception, never written to.

[ tglx: arch/x86 adaptation ]
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Fix the NMI watchdog on Intel CoreDuo processor where the kernel would
get stuck during boot.  The issue is related to errata AE49, where the
PERFEVTSEL1 counter does not have a working enable bit.  Thus it is not
possible to use it for NMI.

The patch creates a dedicated wd_ops for CoreDuo which falls back to
using PERFEVTSEL0.  The other Intel processors supporting the
architectural PMU will keep on using PERFEVTSEL1 as this allows other
subsystems, such as perfmon, to use PERFEVTSEL0 for PEBS monitoring in
particular.  Bug initially reported by Daniel Walker.

AK: Added comments
Signed-off-by: NStephane Eranian <eranian@hpl.hp.com>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The performance counters on K7 are only 48 bits wide, so using bit 63 to
check if the counter overflowed is wrong. Let's use bit 47 instead.
Signed-off-by: NBjörn Steinbrink <B.Steinbrink@gmx.de>
Cc: Don Zickus <dzickus@redhat.com>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I got an oops while booting a 32bit kernel on KVM because it doesn't
implement performance counters used by the NMI watchdog. Handle this
case.

Cc: Avi Kivity <avi@qumranet.com>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The Intel PerfMon NMI watchdog reserves the first performance counter,
but uses the second one. Make it correctly reserve the second one.
Signed-off-by: NBjörn Steinbrink <B.Steinbrink@gmx.de>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

With this change it works again when the nmi watchdog is disabled.
Signed-off-by: NAndi Kleen <ak@suse.de>
Cc: Björn Steinbrink <B.Steinbrink@gmx.de>
Cc: Stephane Eranian <eranian@hpl.hp.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix oops triggered during: echo 0 > /proc/sys/kernel/nmi_watchdog

The culprit seems to be 09198e68:
[PATCH] i386: Clean up NMI watchdog code

In two places, the parameters to release_{evntsel,perfctr}_nmi
got interchanged during the cleanup.

Fix interchanged parameters to release_{evntsel,perfctr}_nmi.
Signed-off-by: NBjörn Steinbrink <B.Steinbrink@gmx.de>
Cc: Stephane Eranian <eranian@hpl.hp.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Michal Piotrowski <michal.k.k.piotrowski@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When disabled through /proc/sys/kernel/nmi_watchdog, the NMI watchdog uses the
stop() method directly, which does not decrement the activity counter, leading
to a BUG().  Use the wrapper function instead to fix that.
Signed-off-by: NBjörn Steinbrink <B.Steinbrink@gmx.de>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

At system boot time, the NMI watchdog no longer reserved its MSRs, allowing
other subsystems to mess with them.  Fix that.
Signed-off-by: NBjörn Steinbrink <B.Steinbrink@gmx.de>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

- Introduce a wd_ops structure
- Convert the various nmi watchdogs over to it
- This allows to split the perfctr reservation from the watchdog
setup cleanly.
- Do perfctr reservation globally as it should have always been
- Remove dead code referenced only by unused EXPORT_SYMBOLs
Signed-off-by: NAndi Kleen <ak@suse.de>