The validate_group() function needs to validate events with
extra shared regs. Within an event group, only events with
the same value for the extra reg can co-exist. This was not
checked by validate_group() because it was missing the
shared_regs logic.

This patch changes the allocation of the fake cpuc used for
validation to also point to a fake shared_regs structure such
that group events be properly testing.

It modifies __intel_shared_reg_get_constraints() to use
spin_lock_irqsave() to avoid lockdep issues.
Signed-off-by: NStephane Eranian <eranian@google.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110606145708.GA7279@quadSigned-off-by: NIngo Molnar <mingo@elte.hu>

This patch improves the code managing the extra shared registers
used for offcore_response events on Intel Nehalem/Westmere. The
idea is to use static allocation instead of dynamic allocation.
This simplifies greatly the get and put constraint routines for
those events.

The patch also renames per_core to shared_regs because the same
data structure gets used whether or not HT is on. When HT is
off, those events still need to coordination because they use
a extra MSR that has to be shared within an event group.
Signed-off-by: NStephane Eranian <eranian@google.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110606145703.GA7258@quadSigned-off-by: NIngo Molnar <mingo@elte.hu>

The nmi parameter indicated if we could do wakeups from the current
context, if not, we would set some state and self-IPI and let the
resulting interrupt do the wakeup.

For the various event classes:

  - hardware: nmi=0; PMI is in fact an NMI or we run irq_work_run from
    the PMI-tail (ARM etc.)
  - tracepoint: nmi=0; since tracepoint could be from NMI context.
  - software: nmi=[0,1]; some, like the schedule thing cannot
    perform wakeups, and hence need 0.

As one can see, there is very little nmi=1 usage, and the down-side of
not using it is that on some platforms some software events can have a
jiffy delay in wakeup (when arch_irq_work_raise isn't implemented).

The up-side however is that we can remove the nmi parameter and save a
bunch of conditionals in fast paths.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Michael Cree <mcree@orcon.net.nz>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Eric B Munson <emunson@mgebm.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/n/tip-agjev8eu666tvknpb3iaj0fg@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>

The Intel Nehalem offcore bits implemented in:

  e994d7d2: perf: Fix LLC-* events on Intel Nehalem/Westmere

... are wrong: they implemented _ACCESS as _HIT and counted OTHER_CORE_HIT* as
MISS even though its clearly documented as an L3 hit ...

Fix them and the Westmere definitions as well.

Cc: Andi Kleen <ak@linux.intel.com>
Cc: Lin Ming <ming.m.lin@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1299119690-13991-3-git-send-email-ming.m.lin@intel.comSigned-off-by: NIngo Molnar <mingo@elte.hu>

Extend the Intel SandyBridge PMU driver with definitions
for generic front-end and back-end stall events.

( As commit 30112039 "perf events, x86: Add Westmere stalled-cycles-frontend/backend
  events" says, these are only approximations. )
Signed-off-by: NLin Ming <ming.m.lin@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1304666042-17577-1-git-send-email-ming.m.lin@intel.comSigned-off-by: NIngo Molnar <mingo@elte.hu>

Extend the Intel Westmere PMU driver with definitions for generic front-end and
back-end stall events.

( These are only approximations. )
Reported-by: NDavid Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/n/tip-7y40wib8n008io7hjpn1dsrm@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>

Extend the Intel and AMD event definitions with generic front-end and
back-end stall events.

( These are only approximations - suggestions are welcome for better events. )

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/n/tip-7y40wib8n001io7hjpn1dsrm@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>

Add two generic hardware events: front-end and back-end stalled cycles.

These events measure conditions when the CPU is executing code but its
capabilities are not fully utilized. Understanding such situations and
analyzing them is an important sub-task of code optimization workflows.

Both events limit performance: most front end stalls tend to be caused
by branch misprediction or instruction fetch cachemisses, backend
stalls can be caused by various resource shortages or inefficient
instruction scheduling.

Front-end stalls are the more important ones: code cannot run fast
if the instruction stream is not being kept up.

An over-utilized back-end can cause front-end stalls and thus
has to be kept an eye on as well.

The exact composition is very program logic and instruction mix
dependent.

We use the terms 'stall', 'front-end' and 'back-end' loosely and
try to use the best available events from specific CPUs that
approximate these concepts.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/n/tip-7y40wib8n000io7hjpn1dsrm@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>

Use the UOPS_EXECUTED.*,c=1,i=1 event on Intel CPUs - it is a rather
good indicator of CPU execution stalls, more sensitive and more inclusive
than the 0xa2 resource stalls event (which does not count nearly as many
stall types).

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/n/tip-7y40wib8n1eqio7hjpn2dsrm@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>

It was noticed that P4 machines were generating double NMIs for
each perf event.  These extra NMIs lead to 'Dazed and confused'
messages on the screen.

I tracked this down to a P4 quirk that said the overflow bit had
to be cleared before re-enabling the apic LVT mask.  My first
attempt was to move the un-masking inside the perf nmi handler
from before the chipset NMI handler to after.

This broke Nehalem boxes that seem to like the unmasking before
the counters themselves are re-enabled.

In order to keep this change simple for 2.6.39, I decided to
just simply move the apic LVT un-masking to the beginning of all
the chipset NMI handlers, with the exception of Pentium4's to
fix the double NMI issue.

Later on we can move the un-masking to later in the handlers to
save a number of 'extra' NMIs on those particular chipsets.

I tested this change on a P4 machine, an AMD machine, a Nehalem
box, and a core2quad box.  'perf top' worked correctly along
with various other small 'perf record' runs.  Anything high
stress breaks all the machines but that is a different problem.

Thanks to various people for testing different versions of this
patch.
Reported-and-tested-by: NShaun Ruffell <sruffell@digium.com>
Signed-off-by: NDon Zickus <dzickus@redhat.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Link: http://lkml.kernel.org/r/1303900353-10242-1-git-send-email-dzickus@redhat.comSigned-off-by: NIngo Molnar <mingo@elte.hu>
CC: Cyrill Gorcunov <gorcunov@gmail.com>

Various constraint tables were not marked read-mostly.
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/n/tip-wpqwwvmhxucy5e718wnamjiv@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>

The new PERF_COUNT_HW_STALLED_CYCLES event tries to approximate
cycles the CPU does nothing useful, because it is stalled on a
cache-miss or some other condition.
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/n/tip-fue11vymwqsoo5to72jxxjyl@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>

On Nehalem CPUs the retired branch-misses event can be completely bogus,
when there are no branch-misses occuring. When there are a lot of branch
misses then the count is pretty accurate. Still, this leaves us with an
event that over-counts a lot.

Detect this erratum and work it around by using BR_MISP_EXEC.ANY events.
These will also count speculated branches but still it's a lot more
precise in practice than the architectural event.
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/n/tip-yyfg0bxo9jsqxd6a0ovfny27@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>

Currently the x86 backend incorrectly assumes that any BRANCH_INSN
with sample_period==1 is a BTS request. This is not true when we do
frequency driven profiling such as 'perf record -e branches'.

Solves this error:

  $ perf record -e branches ./array
  Error: sys_perf_event_open() syscall returned with 95 (Operation not supported).
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Reported-by: NIngo Molnar <mingo@elte.hu>
Cc: "Metzger, Markus T" <markus.t.metzger@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/n/tip-rd2y4ct71hjawzz6fpvsy9hg@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>

Change the Nehalem cache events to use retired memory instruction counters
(similar to Westmere), this greatly improves the provided stats.

Using:

main ()
{
        int i;

        for (i = 0; i < 1000000000; i++) {
                asm("mov (%%rsp), %%rbx;"
                    "mov %%rbx, (%%rsp);" : : : "rbx");
        }
}

We find:

 $ perf stat --repeat 10 -e instructions:u -e l1-dcache-loads:u -e l1-dcache-stores:u ./loop_1b_loads+stores
  Performance counter stats for './loop_1b_loads+stores' (10 runs):
      4,000,081,056 instructions:u           #      0.000 IPC ( +-   0.000% )
      4,999,502,846 l1-dcache-loads:u          ( +-   0.008% )
      1,000,034,832 l1-dcache-stores:u         ( +-   0.000% )
         1.565184942  seconds time elapsed   ( +-   0.005% )

The 5b is surprising - we'd expect 1b:

 $ perf stat --repeat 10 -e instructions:u -e r10b:u -e l1-dcache-stores:u ./loop_1b_loads+stores
  Performance counter stats for './loop_1b_loads+stores' (10 runs):
      4,000,081,054 instructions:u           #      0.000 IPC ( +-   0.000% )
      1,000,021,961 r10b:u                     ( +-   0.000% )
      1,000,030,951 l1-dcache-stores:u         ( +-   0.000% )
         1.565055422  seconds time elapsed   ( +-   0.003% )

Which this patch thus fixes.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Lin Ming <ming.m.lin@intel.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Link: http://lkml.kernel.org/n/tip-q9rtru7b7840tws75xzboapv@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>

There's a new model number public, 47, for Xeon E7 (aka Westmere EX).
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Cc: a.p.zijlstra@chello.nl
Link: http://lkml.kernel.org/r/1303429715-10202-1-git-send-email-andi@firstfloor.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NLin Ming <ming.m.lin@intel.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1299119690-13991-5-git-send-email-ming.m.lin@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

On Intel Nehalem and Westmere CPUs the generic perf LLC-* events count the
L2 caches, not the real L3 LLC - this was inconsistent with behavior on
other CPUs.

Fixing this requires the use of the special OFFCORE_RESPONSE
events which need a separate mask register.

This has been implemented by the previous patch, now use this infrastructure
to set correct events for the LLC-* on Nehalem and Westmere.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NLin Ming <ming.m.lin@intel.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1299119690-13991-3-git-send-email-ming.m.lin@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Change logs against Andi's original version:

- Extends perf_event_attr:config to config{,1,2} (Peter Zijlstra)
- Fixed a major event scheduling issue. There cannot be a ref++ on an
  event that has already done ref++ once and without calling
  put_constraint() in between. (Stephane Eranian)
- Use thread_cpumask for percore allocation. (Lin Ming)
- Use MSR names in the extra reg lists. (Lin Ming)
- Remove redundant "c = NULL" in intel_percore_constraints
- Fix comment of perf_event_attr::config1

Intel Nehalem/Westmere have a special OFFCORE_RESPONSE event
that can be used to monitor any offcore accesses from a core.
This is a very useful event for various tunings, and it's
also needed to implement the generic LLC-* events correctly.

Unfortunately this event requires programming a mask in a separate
register. And worse this separate register is per core, not per
CPU thread.

This patch:

- Teaches perf_events that OFFCORE_RESPONSE needs extra parameters.
  The extra parameters are passed by user space in the
  perf_event_attr::config1 field.

- Adds support to the Intel perf_event core to schedule per
  core resources. This adds fairly generic infrastructure that
  can be also used for other per core resources.
  The basic code has is patterned after the similar AMD northbridge
  constraints code.

Thanks to Stephane Eranian who pointed out some problems
in the original version and suggested improvements.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NLin Ming <ming.m.lin@intel.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1299119690-13991-2-git-send-email-ming.m.lin@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch updates PEBS event constraints for Intel Atom, Nehalem, Westmere.

This patch also reorganizes the PEBS format/constraint detection code. It is
now based on processor model and not PEBS format. Two processors may use the
same PEBS format without have the same list of PEBS events.

In this second version, we simplified the initialization of the PEBS
constraints by leveraging the existing switch() statement in perf_event_intel.c.
We also renamed the constraint tables to be more consistent with regular
constraints.

In this 3rd version, we drop BR_INST_RETIRED.MISPRED from Intel Atom as it does
not seem to work. Use MISPREDICTED_BRANCH_RETIRED instead. Also add FP_ASSIST.*
o both Intel Nehalem and Westmere. I misssed those in the earlier patches.
Events were tested using libpfm4 perf_examples.
Signed-off-by: NStephane Eranian <eranian@google.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <4d6e6b02.815bdf0a.637b.07a7@mx.google.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch adds basic SandyBridge support, including hardware
cache events and PEBS events support.

It has been tested on SandyBridge CPUs with perf stat and also
with PEBS based profiling - both work fine.

The patch does not affect other models.

v2 -> v3:
 - fix PEBS event 0xd0 with right umask combinations
 - move snb pebs constraint assignment to intel_pmu_init

v1 -> v2:
 - add more raw and PEBS events constraints
 - use offcore events for LLC-* cache events
 - remove the call to Nehalem workaround enable_all function
Signed-off-by: NLin Ming <ming.m.lin@intel.com>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Andi Kleen <andi@firstfloor.org>
LKML-Reference: <1299072424.2175.24.camel@localhost>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch adds helper functions to calculate perfctr msr addresses.
We need this to later add support for AMD family 15h cpus. For this we
have to change the algorithms to generate the perfctr's msr addresses.
Signed-off-by: NRobert Richter <robert.richter@amd.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1296664860-10886-3-git-send-email-robert.richter@amd.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Go through x86 code and replace __get_cpu_var and get_cpu_var
instances that refer to a scalar and are not used for address
determinations.

Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: NTejun Heo <tj@kernel.org>
Acked-by: N"H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: NChristoph Lameter <cl@linux.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Fix a bug introduced with commit de725dec and the change in the
meaning of the return value of intel_pmu_handle_irq(). With the
current code, when you are using the BTS, you get 'dazed by NMI'
each time the BTS buffer fills up.

BTS does interrupt on the PMU vector, thus NMI. You need to take
this into account in the return value of the function.

This version fixes initial patch which was missing changes to
perf_event_intel_ds.c.
Signed-off-by: NStephane Eranian <eranian@google.com>
Acked-by: NDon Zickus <dzickus@redhat.com>
Cc: peterz@infradead.org
Cc: paulus@samba.org
Cc: davem@davemloft.net
Cc: fweisbec@gmail.com
Cc: perfmon2-devel@lists.sf.net
Cc: eranian@gmail.com
Cc: robert.richter@amd.com
LKML-Reference: <4c8a1686.aae9d80a.5aa4.5e35@mx.google.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Replace pmu::{enable,disable,start,stop,unthrottle} with
pmu::{add,del,start,stop}, all of which take a flags argument.

The new interface extends the capability to stop a counter while
keeping it scheduled on the PMU. We replace the throttled state with
the generic stopped state.

This also allows us to efficiently stop/start counters over certain
code paths (like IRQ handlers).

It also allows scheduling a counter without it starting, allowing for
a generic frozen state (useful for rotating stopped counters).

The stopped state is implemented in two different ways, depending on
how the architecture implemented the throttled state:

 1) We disable the counter:
    a) the pmu has per-counter enable bits, we flip that
    b) we program a NOP event, preserving the counter state

 2) We store the counter state and ignore all read/overflow events
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: paulus <paulus@samba.org>
Cc: stephane eranian <eranian@googlemail.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Lin Ming <ming.m.lin@intel.com>
Cc: Yanmin <yanmin_zhang@linux.intel.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
Cc: David Miller <davem@davemloft.net>
Cc: Michael Cree <mcree@orcon.net.nz>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Now that we rely on the number of handled overflows, ensure all
handle_irq implementations actually return the right number.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NDon Zickus <dzickus@redhat.com>
Cc: peterz@infradead.org
Cc: robert.richter@amd.com
Cc: gorcunov@gmail.com
Cc: fweisbec@gmail.com
Cc: ying.huang@intel.com
Cc: ming.m.lin@intel.com
Cc: eranian@google.com
LKML-Reference: <1283454469-1909-4-git-send-email-dzickus@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

During testing of a patch to stop having the perf subsytem
swallow nmis, it was uncovered that Nehalem boxes were randomly
getting unknown nmis when using the perf tool.

Moving the ack'ing of the PMI closer to when we get the status
allows the hardware to properly re-set the PMU bit signaling
another PMI was triggered during the processing of the first
PMI.  This allows the new logic for dealing with the
shortcomings of multiple PMIs to handle the extra NMI by
'eat'ing it later.

Now one can wonder why are we getting a second PMI when we
disable all the PMUs in the begining of the NMI handler to
prevent such a case, for that I do not know.  But I know the fix
below helps deal with this quirk.

Tested on multiple Nehalems where the problem was occuring.
With the patch, the code now loops a second time to handle the
second PMI (whereas before it was not).
Signed-off-by: NDon Zickus <dzickus@redhat.com>
Cc: peterz@infradead.org
Cc: robert.richter@amd.com
Cc: gorcunov@gmail.com
Cc: fweisbec@gmail.com
Cc: ying.huang@intel.com
Cc: ming.m.lin@intel.com
Cc: eranian@google.com
LKML-Reference: <1283454469-1909-2-git-send-email-dzickus@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Fix the Errata AAK100/AAP53/BD53 workaround, the officialy documented
workaround we implemented in:

 11164cd4: perf, x86: Add Nehelem PMU programming errata workaround

doesn't actually work fully and causes a stuck PMU state
under load and non-functioning perf profiling.

A functional workaround was found by trial & error.

Affects all Nehalem-class Intel PMUs.
Signed-off-by: NZhang Yanmin <yanmin_zhang@linux.intel.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1281073148.2125.63.camel@ymzhang.sh.intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <stable@kernel.org> # .35.x
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Based on Intel Vol3b (March 2010), the event
SNOOPQ_REQUEST_OUTSTANDING is restricted to counters 0,1 so
update the event table for Intel Westmere accordingly.
Signed-off-by: NStephane Eranian <eranian@google.com>
Cc: peterz@infradead.org
Cc: paulus@samba.org
Cc: davem@davemloft.net
Cc: fweisbec@gmail.com
Cc: perfmon2-devel@lists.sf.net
Cc: eranian@gmail.com
Cc: <stable@kernel.org> # .34.x
LKML-Reference: <4c10cb56.5120e30a.2eb4.ffffc3de@mx.google.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Rename perf_event_attr::precise to perf_event_attr::precise_ip and
widen it to 2 bits. This new field describes the required precision of
the PERF_SAMPLE_IP field:

  0 - SAMPLE_IP can have arbitrary skid
  1 - SAMPLE_IP must have constant skid
  2 - SAMPLE_IP requested to have 0 skid
  3 - SAMPLE_IP must have 0 skid

And modify the Intel PEBS code accordingly. The PEBS implementation
now supports up to precise_ip == 2, where we perform the IP fixup.

Also s/PERF_RECORD_MISC_EXACT/&_IP/ to clarify its meaning, this bit
should be set for each PERF_SAMPLE_IP field known to match the actual
instruction triggering the event.

This new scheme allows for a PEBS mode that uses the buffer for more
than a single event.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

To reuse this function for events with different enable bit masks,
this mask is part of the function's argument list now.

The function will be used later to control ibs events too.
Signed-off-by: NRobert Richter <robert.richter@amd.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1271190201-25705-6-git-send-email-robert.richter@amd.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

According to Intel Software Devel Manual Volume 3B, the
Nehalem-EX PMU is just like regular Nehalem (except for the
uncore support, which is completely different).
Signed-off-by: NVince Weaver <vweaver1@eecs.utk.edu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Lin Ming <ming.m.lin@intel.com>
LKML-Reference: <alpine.DEB.2.00.1004060956580.1417@cl320.eecs.utk.edu>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

According to the Xeon-5600 errata the Westmere suffers the same PMU
programming bug as the original Nehalem did.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

All variables that have __initconst should also be const.
Suggested-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Stephane noticed that the ANY flag was in generic arch code, and Cyrill
reported that it broke the P4 code.

Solve this by merging x86_pmu::raw_event into x86_pmu::hw_config and
provide intel_pmu and amd_pmu specific versions of this callback.

The intel_pmu one deals with the ANY flag, the amd_pmu adds the few extra
event bits AMD64 has.
Reported-by: NStephane Eranian <eranian@google.com>
Reported-by: NCyrill Gorcunov <gorcunov@gmail.com>
Acked-by: NRobert Richter <robert.richter@amd.com>
Acked-by: NCyrill Gorcunov <gorcunov@gmail.com>
Acked-by: NStephane Eranian <eranian@google.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1269968113.5258.442.camel@laptop>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

ARCH_PERFMON_EVENTSEL bit masks are often used in the kernel. This
patch adds macros for the bit masks and removes local defines. The
function intel_pmu_raw_event() becomes x86_pmu_raw_event() which is
generic for x86 models and same also for p6. Duplicate code is
removed.
Signed-off-by: NRobert Richter <robert.richter@amd.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20100330092821.GH11907@erda.amd.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The big rename:

 cdd6c482 perf: Do the big rename: Performance Counters -> Performance Events

accidentally renamed some members of stucts that were named after
registers in the spec. To avoid confusion this patch reverts some
changes. The related specs are MSR descriptions in AMD's BKDGs and the
ARCHITECTURAL PERFORMANCE MONITORING section in the Intel 64 and IA-32
Architectures Software Developer's Manuals.

This patch does:

 $ sed -i -e 's:num_events:num_counters:g' \
   arch/x86/include/asm/perf_event.h \
   arch/x86/kernel/cpu/perf_event_amd.c \
   arch/x86/kernel/cpu/perf_event.c \
   arch/x86/kernel/cpu/perf_event_intel.c \
   arch/x86/kernel/cpu/perf_event_p6.c \
   arch/x86/kernel/cpu/perf_event_p4.c \
   arch/x86/oprofile/op_model_ppro.c

 $ sed -i -e 's:event_bits:cntval_bits:g' -e 's:event_mask:cntval_mask:g' \
   arch/x86/kernel/cpu/perf_event_amd.c \
   arch/x86/kernel/cpu/perf_event.c \
   arch/x86/kernel/cpu/perf_event_intel.c \
   arch/x86/kernel/cpu/perf_event_p6.c \
   arch/x86/kernel/cpu/perf_event_p4.c
Signed-off-by: NRobert Richter <robert.richter@amd.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1269880612-25800-2-git-send-email-robert.richter@amd.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Implement the workaround for Intel Errata AAK100 and AAP53.

Also, remove the Core-i7 name for Nehalem events since there are
also Westmere based i7 chips.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <1269608924.12097.147.camel@laptop>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The netburst PMU is way different from the "architectural
perfomance monitoring" specification that current CPUs use.
P4 uses a tuple of ESCR+CCCR+COUNTER MSR registers to handle
perfomance monitoring events.

A few implementational details:

1) We need a separate x86_pmu::hw_config helper in struct
   x86_pmu since register bit-fields are quite different from P6,
   Core and later cpu series.

2) For the same reason is a x86_pmu::schedule_events helper
   introduced.

3) hw_perf_event::config consists of packed ESCR+CCCR values.
   It's allowed since in reality both registers only use a half
   of their size. Of course before making a real write into a
   particular MSR we need to unpack the value and extend it to
   a proper size.

4) The tuple of packed ESCR+CCCR in hw_perf_event::config
   doesn't describe the memory address of ESCR MSR register
   so that we need to keep a mapping between these tuples
   used and available ESCR (various P4 events may use same
   ESCRs but not simultaneously), for this sake every active
   event has a per-cpu map of hw_perf_event::idx <--> ESCR
   addresses.

5) Since hw_perf_event::idx is an offset to counter/control register
   we need to lift X86_PMC_MAX_GENERIC up, otherwise kernel
   strips it down to 8 registers and event armed may never be turned
   off (ie the bit in active_mask is set but the loop never reaches
   this index to check), thanks to Peter Zijlstra

Restrictions:

 - No cascaded counters support (do we ever need them?)
 - No dependent events support (so PERF_COUNT_HW_INSTRUCTIONS
   doesn't work for now)
 - There are events with same counters which can't work simultaneously
   (need to use intersected ones due to broken counter 1)
 - No PERF_COUNT_HW_CACHE_ events yet

Todo:

 - Implement dependent events
 - Need proper hashing for event opcodes (no linear search, good for
   debugging stage but not in real loads)
 - Some events counted during a clock cycle -- need to set threshold
   for them and count every clock cycle just to get summary statistics
   (ie to behave the same way as other PMUs do)
 - Need to swicth to use event_constraints
 - To support RAW events we need to encode a global list of P4 events
   into p4_templates
 - Cache events need to be added

Event support status matrix:

 Event			status
 -----------------------------
 cycles			works
 cache-references	works
 cache-misses		works
 branch-misses		works
 bus-cycles		partially (does not work on 64bit cpu with HT enabled)
 instruction		doesnt work (needs dependent event [mop tagging])
 branches		doesnt work
Signed-off-by: NCyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: NLin Ming <ming.m.lin@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100311165439.GB5129@lenovo>
Signed-off-by: NIngo Molnar <mingo@elte.hu>