On -rt kfree() can schedule, but CPU_STARTING is before the CPU is
fully up and running. These are contradictory, so avoid it. Instead
push the kfree() to CPU_ONLINE where we're free to schedule.
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-kwd4j6ayld5thrscvaxgjquv@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
copy_from_user_nmi() is used in oprofile and perf. Moving it to other
library functions like copy_from_user(). As this is x86 code for 32
and 64 bits, create a new file usercopy.c for unified code.
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110607172413.GJ20052@erda.amd.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Instead of hw_nmi_watchdog_set_attr() weak function
and appropriate x86_pmu::hw_watchdog_set_attr() call
we introduce even alias mechanism which allow us
to drop this routines completely and isolate quirks
of Netburst architecture inside P4 PMU code only.
The main idea remains the same though -- to allow
nmi-watchdog and perf top run simultaneously.
Note the aliasing mechanism applies to generic
PERF_COUNT_HW_CPU_CYCLES event only because arbitrary
event (say passed as RAW initially) might have some
additional bits set inside ESCR register changing
the behaviour of event and we can't guarantee anymore
that alias event will give the same result.
P.S. Thanks a huge to Don and Steven for for testing
and early review.
Acked-by: Don Zickus <dzickus@redhat.com>
Tested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
CC: Ingo Molnar <mingo@elte.hu>
CC: Peter Zijlstra <a.p.zijlstra@chello.nl>
CC: Stephane Eranian <eranian@google.com>
CC: Lin Ming <ming.m.lin@intel.com>
CC: Arnaldo Carvalho de Melo <acme@redhat.com>
CC: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/20110708201712.GS23657@sun
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Since the OFFCORE registers are fully symmetric, try the other one
when the specified one is already in use.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1306141897.18455.8.camel@twins
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch adds Intel Sandy Bridge offcore_response support by
providing the low-level constraint table for those events.
On Sandy Bridge, there are two offcore_response events. Each uses
its own dedictated extra register. But those registers are NOT shared
between sibling CPUs when HT is on unlike Nehalem/Westmere. They are
always private to each CPU. But they still need to be controlled within
an event group. All events within an event group must use the same
value for the extra MSR. That's not controlled by the second patch in
this series.
Furthermore on Sandy Bridge, the offcore_response events have NO
counter constraints contrary to what the official documentation
indicates, so drop the events from the contraint table.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110606145712.GA7304@quad
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110606145708.GA7279@quad
Signed-off-by: Ingo 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: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110606145703.GA7258@quad
Signed-off-by: Ingo 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: Peter 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.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Due to restriction and specifics of Netburst PMU we need a separated
event for NMI watchdog. In particular every Netburst event
consumes not just a counter and a config register, but also an
additional ESCR register.
Since ESCR registers are grouped upon counters (i.e. if ESCR is occupied
for some event there is no room for another event to enter until its
released) we need to pick up the "least" used ESCR (or the most available
one) for nmi-watchdog purposes -- so MSR_P4_CRU_ESCR2/3 was chosen.
With this patch nmi-watchdog and perf top should be able to run simultaneously.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
CC: Lin Ming <ming.m.lin@intel.com>
CC: Arnaldo Carvalho de Melo <acme@redhat.com>
CC: Frederic Weisbecker <fweisbec@gmail.com>
Tested-and-reviewed-by: Don Zickus <dzickus@redhat.com>
Tested-and-reviewed-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110623124918.GC13050@sun
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Both warning and warning_symbol are nowhere used.
Let's get rid of them.
Signed-off-by: Richard Weinberger <richard@nod.at>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Soeren Sandmann Pedersen <ssp@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: x86 <x86@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Link: http://lkml.kernel.org/r/1305205872-10321-2-git-send-email-richard@nod.at
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
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: Shaun Ruffell <sruffell@digium.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Link: http://lkml.kernel.org/r/1303900353-10242-1-git-send-email-dzickus@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
CC: Cyrill Gorcunov <gorcunov@gmail.com>
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: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reported-by: Ingo 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.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Andi Kleen pointed out that the Intel offcore support patches were merged
without user-space tool support to the functionality:
|
| The offcore_msr perf kernel code was merged into 2.6.39-rc*, but the
| user space bits were not. This made it impossible to set the extra mask
| and actually do the OFFCORE profiling
|
Andi submitted a preliminary patch for user-space support, as an
extension to perf's raw event syntax:
|
| Some raw events -- like the Intel OFFCORE events -- support additional
| parameters. These can be appended after a ':'.
|
| For example on a multi socket Intel Nehalem:
|
| perf stat -e r1b7:20ff -a sleep 1
|
| Profile the OFFCORE_RESPONSE.ANY_REQUEST with event mask REMOTE_DRAM_0
| that measures any access to DRAM on another socket.
|
But this kind of usability is absolutely unacceptable - users should not
be expected to type in magic, CPU and model specific incantations to get
access to useful hardware functionality.
The proper solution is to expose useful offcore functionality via
generalized events - that way users do not have to care which specific
CPU model they are using, they can use the conceptual event and not some
model specific quirky hexa number.
We already have such generalization in place for CPU cache events,
and it's all very extensible.
"Offcore" events measure general DRAM access patters along various
parameters. They are particularly useful in NUMA systems.
We want to support them via generalized DRAM events: either as the
fourth level of cache (after the last-level cache), or as a separate
generalization category.
That way user-space support would be very obvious, memory access
profiling could be done via self-explanatory commands like:
perf record -e dram ./myapp
perf record -e dram-remote ./myapp
... to measure DRAM accesses or more expensive cross-node NUMA DRAM
accesses.
These generalized events would work on all CPUs and architectures that
have comparable PMU features.
( Note, these are just examples: actual implementation could have more
sophistication and more parameter - as long as they center around
similarly simple usecases. )
Now we do not want to revert *all* of the current offcore bits, as they
are still somewhat useful for generic last-level-cache events, implemented
in this commit:
e994d7d23a: perf: Fix LLC-* events on Intel Nehalem/Westmere
But we definitely do not yet want to expose the unstructured raw events
to user-space, until better generalization and usability is implemented
for these hardware event features.
( Note: after generalization has been implemented raw offcore events can be
supported as well: there can always be an odd event that is marginally
useful but not useful enough to generalize. DRAM profiling is definitely
*not* such a category so generalization must be done first. )
Furthermore, PERF_TYPE_RAW access to these registers was not intended
to go upstream without proper support - it was a side-effect of the above
e994d7d23a commit, not mentioned in the changelog.
As v2.6.39 is nearing release we go for the simplest approach: disable
the PERF_TYPE_RAW offcore hack for now, before it escapes into a released
kernel and becomes an ABI.
Once proper structure is implemented for these hardware events and users
are offered usable solutions we can revisit this issue.
Reported-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1302658203-4239-1-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Using ALTERNATIVE() when checking for X86_FEATURE_PERFCTR_CORE avoids
an extra pointer chase and data cache hit.
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1302913676-14352-4-git-send-email-robert.richter@amd.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
perf, x86: Complain louder about BIOSen corrupting CPU/PMU state and continue
perf, x86: P4 PMU - Read proper MSR register to catch unflagged overflows
perf symbols: Look at .dynsym again if .symtab not found
perf build-id: Add quirk to deal with perf.data file format breakage
perf session: Pass evsel in event_ops->sample()
perf: Better fit max unprivileged mlock pages for tools needs
perf_events: Fix stale ->cgrp pointer in update_cgrp_time_from_cpuctx()
perf top: Fix uninitialized 'counter' variable
tracing: Fix set_ftrace_filter probe function display
perf, x86: Fix Intel fixed counters base initialization
Eric Dumazet reported that hardware PMU events do not work on his
system, due to the BIOS corrupting PMU state:
Performance Events: PEBS fmt0+, Core2 events, Broken BIOS detected, using software events only.
[Firmware Bug]: the BIOS has corrupted hw-PMU resources (MSR 186 is 43003c)
Linus suggested that we continue in the face of such BIOS-induced CPU
state corruption:
http://lkml.org/lkml/2011/3/24/608
Such BIOSes will have to be fixed - Linux developers rely on a working and
fully capable PMU and the BIOS interfering with the CPU's PMU state is simply
not acceptable.
So this patch changes perf to continue when it detects such BIOS
interaction, some hardware events may be unreliable due to the BIOS
writing and re-writing them - there's not much the kernel can do
about that but to detect the corruption and report it.
Reported-and-tested-by: Eric Dumazet <eric.dumazet@gmail.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
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>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The following patch solves the problems introduced by Robert's
commit 41bf498 and reported by Arun Sharma. This commit gets rid
of the base + index notation for reading and writing PMU msrs.
The problem is that for fixed counters, the new calculation for
the base did not take into account the fixed counter indexes,
thus all fixed counters were read/written from fixed counter 0.
Although all fixed counters share the same config MSR, they each
have their own counter register.
Without:
$ task -e unhalted_core_cycles -e instructions_retired -e baclears noploop 1 noploop for 1 seconds
242202299 unhalted_core_cycles (0.00% scaling, ena=1000790892, run=1000790892)
2389685946 instructions_retired (0.00% scaling, ena=1000790892, run=1000790892)
49473 baclears (0.00% scaling, ena=1000790892, run=1000790892)
With:
$ task -e unhalted_core_cycles -e instructions_retired -e baclears noploop 1 noploop for 1 seconds
2392703238 unhalted_core_cycles (0.00% scaling, ena=1000840809, run=1000840809)
2389793744 instructions_retired (0.00% scaling, ena=1000840809, run=1000840809)
47863 baclears (0.00% scaling, ena=1000840809, run=1000840809)
Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: peterz@infradead.org
Cc: ming.m.lin@intel.com
Cc: robert.richter@amd.com
Cc: asharma@fb.com
Cc: perfmon2-devel@lists.sf.net
LKML-Reference: <20110319172005.GB4978@quad>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: Flush TLB if PGD entry is changed in i386 PAE mode
x86, dumpstack: Correct stack dump info when frame pointer is available
x86: Clean up csum-copy_64.S a bit
x86: Fix common misspellings
x86: Fix misspelling and align params
x86: Use PentiumPro-optimized partial_csum() on VIA C7
Current stack dump code scans entire stack and check each entry
contains a pointer to kernel code. If CONFIG_FRAME_POINTER=y it
could mark whether the pointer is valid or not based on value of
the frame pointer. Invalid entries could be preceded by '?' sign.
However this was not going to happen because scan start point
was always higher than the frame pointer so that they could not
meet.
Commit 9c0729dc80 ("x86: Eliminate bp argument from the stack
tracing routines") delayed bp acquisition point, so the bp was
read in lower frame, thus all of the entries were marked
invalid.
This patch fixes this by reverting above commit while retaining
stack_frame() helper as suggested by Frederic Weisbecker.
End result looks like below:
before:
[ 3.508329] Call Trace:
[ 3.508551] [<ffffffff814f35c9>] ? panic+0x91/0x199
[ 3.508662] [<ffffffff814f3739>] ? printk+0x68/0x6a
[ 3.508770] [<ffffffff81a981b2>] ? mount_block_root+0x257/0x26e
[ 3.508876] [<ffffffff81a9821f>] ? mount_root+0x56/0x5a
[ 3.508975] [<ffffffff81a98393>] ? prepare_namespace+0x170/0x1a9
[ 3.509216] [<ffffffff81a9772b>] ? kernel_init+0x1d2/0x1e2
[ 3.509335] [<ffffffff81003894>] ? kernel_thread_helper+0x4/0x10
[ 3.509442] [<ffffffff814f6880>] ? restore_args+0x0/0x30
[ 3.509542] [<ffffffff81a97559>] ? kernel_init+0x0/0x1e2
[ 3.509641] [<ffffffff81003890>] ? kernel_thread_helper+0x0/0x10
after:
[ 3.522991] Call Trace:
[ 3.523351] [<ffffffff814f35b9>] panic+0x91/0x199
[ 3.523468] [<ffffffff814f3729>] ? printk+0x68/0x6a
[ 3.523576] [<ffffffff81a981b2>] mount_block_root+0x257/0x26e
[ 3.523681] [<ffffffff81a9821f>] mount_root+0x56/0x5a
[ 3.523780] [<ffffffff81a98393>] prepare_namespace+0x170/0x1a9
[ 3.523885] [<ffffffff81a9772b>] kernel_init+0x1d2/0x1e2
[ 3.523987] [<ffffffff81003894>] kernel_thread_helper+0x4/0x10
[ 3.524228] [<ffffffff814f6880>] ? restore_args+0x0/0x30
[ 3.524345] [<ffffffff81a97559>] ? kernel_init+0x0/0x1e2
[ 3.524445] [<ffffffff81003890>] ? kernel_thread_helper+0x0/0x10
-v5:
* fix build breakage with oprofile
-v4:
* use 0 instead of regs->bp
* separate out printk changes
-v3:
* apply comment from Frederic
* add a couple of printk fixes
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Soren Sandmann <ssp@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Robert Richter <robert.richter@amd.com>
LKML-Reference: <1300416006-3163-1-git-send-email-namhyung@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
They were generated by 'codespell' and then manually reviewed.
Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Cc: trivial@kernel.org
LKML-Reference: <1300389856-1099-3-git-send-email-lucas.demarchi@profusion.mobi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
PEBS_EVENT_CONSTRAINT() is just a duplicate of INTEL_UEVENT_CONSTRAINT().
Remove it and use INTEL_UEVENT_CONSTRAINT() instead.
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1299684089-22835-3-git-send-email-ming.m.lin@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1299119690-13991-5-git-send-email-ming.m.lin@intel.com>
Signed-off-by: Ingo 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: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1299119690-13991-3-git-send-email-ming.m.lin@intel.com>
Signed-off-by: Ingo 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: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1299119690-13991-2-git-send-email-ming.m.lin@intel.com>
Signed-off-by: Ingo 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: Lin Ming <ming.m.lin@intel.com>
Acked-by: Peter 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: Ingo Molnar <mingo@elte.hu>
This patch adds support for AMD family 15h core counters. There are
major changes compared to family 10h. First, there is a new perfctr
msr range for up to 6 counters. Northbridge counters are separate
now. This patch only adds support for core counters. Second, certain
events may only be scheduled on certain counters. For this we need to
extend the event scheduling and constraints.
We use cpu feature flags to calculate family 15h msr address offsets.
This way we later can implement a faster ALTERNATIVE() version for
this.
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20110215135210.GB5874@erda.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Instead of storing the base addresses we can store the counter's msr
addresses directly in config_base/event_base of struct hw_perf_event.
This avoids recalculating the address with each msr access. The
addresses are configured one time. We also need this change to later
modify the address calculation.
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1296664860-10886-5-git-send-email-robert.richter@amd.com>
Signed-off-by: Ingo 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: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1296664860-10886-3-git-send-email-robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Use helper function in x86_pmu_enable_all() to minimize access to
x86_pmu.eventsel in the fast path. The counter's msr address is now
calculated using struct hw_perf_event. Later we add code that
calculates the msr addresses with a table lookup which shouldn't be
done in the fast path.
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1296664860-10886-2-git-send-email-robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
init_hw_perf_events() is called via early_initcall now.
x86_pmu_event_init is x86_pmu member function.
So we can change them to static.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
LKML-Reference: <4D3A16F9.109@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (30 commits)
gameport: use this_cpu_read instead of lookup
x86: udelay: Use this_cpu_read to avoid address calculation
x86: Use this_cpu_inc_return for nmi counter
x86: Replace uses of current_cpu_data with this_cpu ops
x86: Use this_cpu_ops to optimize code
vmstat: User per cpu atomics to avoid interrupt disable / enable
irq_work: Use per cpu atomics instead of regular atomics
cpuops: Use cmpxchg for xchg to avoid lock semantics
x86: this_cpu_cmpxchg and this_cpu_xchg operations
percpu: Generic this_cpu_cmpxchg() and this_cpu_xchg support
percpu,x86: relocate this_cpu_add_return() and friends
connector: Use this_cpu operations
xen: Use this_cpu_inc_return
taskstats: Use this_cpu_ops
random: Use this_cpu_inc_return
fs: Use this_cpu_inc_return in buffer.c
highmem: Use this_cpu_xx_return() operations
vmstat: Use this_cpu_inc_return for vm statistics
x86: Support for this_cpu_add, sub, dec, inc_return
percpu: Generic support for this_cpu_add, sub, dec, inc_return
...
Fixed up conflicts: in arch/x86/kernel/{apic/nmi.c, apic/x2apic_uv_x.c, process.c}
as per Tejun.
With priorities in place and no one really understanding the difference between
DIE_NMI and DIE_NMI_IPI, just remove DIE_NMI_IPI and convert everyone to DIE_NMI.
This also simplifies default_do_nmi() a little bit. Instead of calling the
die_notifier in both the if and else part, just pull it out and call it before
the if-statement. This has the side benefit of avoiding a call to the ioport
to see if there is an external NMI sitting around until after the (more frequent)
internal NMIs are dealt with.
Patch-Inspired-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1294348732-15030-5-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In order to consolidate the NMI die_chain events, we need to setup the priorities
for the die notifiers.
I started by defining a bunch of common priorities that can be used by the
notifier blocks. Then I modified the notifier blocks to use the newly created
priorities.
Now that the priorities are straightened out, it should be easier to remove the
event DIE_NMI_IPI.
Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1294348732-15030-4-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo 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: Tejun Heo <tj@kernel.org>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Extend the perf_pmu_register() interface to allow for named and
dynamic pmu types.
Because we need to support the existing static types we cannot use
dynamic types for everything, hence provide a type argument.
If we want to enumerate the PMUs they need a name, provide one.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20101117222056.259707703@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Some BIOSes use PMU resources, which can cause various bugs:
- Non-working or erratic PMU based statistics - the PMU can end up
counting the wrong thing, resulting in misleading statistics
- Profiling can stop working or it can profile the wrong thing
- A non-working or erratic NMI watchdog that cannot be relied on
- The kernel may disturb whatever thing the BIOS tries to use the
PMU for - possibly causing hardware malfunction in extreme cases.
- ... and other forms of potential misbehavior
Various forms of such misbehavior has been observed in practice - there are
BIOSes that just corrupt the PMU state, consequences be damned.
The PMU is a CPU resource that is handled by the kernel and the BIOS
stealing+corrupting it is not acceptable nor robust, so we detect it,
warn about it and further refuse to touch the PMU ourselves.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The perf hardware pmu got initialized at various points in the boot,
some before early_initcall() some after (notably arch_initcall).
The problem is that the NMI lockup detector is ran from early_initcall()
and expects the hardware pmu to be present.
Sanitize this by moving all architecture hardware pmu implementations to
initialize at early_initcall() and move the lockup detector to an explicit
initcall right after that.
Cc: paulus <paulus@samba.org>
Cc: davem <davem@davemloft.net>
Cc: Michael Cree <mcree@orcon.net.nz>
Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1290707759.2145.119.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
and use it when appropriate.
Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1290525705-6265-1-git-send-email-fbuihuu@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In a kvm virt guests, the perf counters are not emulated. Instead they
return zero on a rdmsrl. The perf nmi handler uses the fact that crossing
a zero means the counter overflowed (for those counters that do not have
specific interrupt bits). Therefore on kvm guests, perf will swallow all
NMIs thinking the counters overflowed.
This causes problems for subsystems like kgdb which needs NMIs to do its
magic. This problem was discovered by running kgdb tests.
The solution is to write garbage into a perf counter during the
initialization and hopefully reading back the same number. On kvm
guests, the value will be read back as zero and we disable perf as
a result.
Reported-by: Jason Wessel <jason.wessel@windriver.com>
Patch-inspired-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <1290462923-30734-1-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The various stack tracing routines take a 'bp' argument in which the
caller is supposed to provide the base pointer to use, or 0 if doesn't
have one. Since bp is garbage whenever CONFIG_FRAME_POINTER is not
defined, this means all callers in principle should either always pass
0, or be conditional on CONFIG_FRAME_POINTER.
However, there are only really three use cases for stack tracing:
(a) Trace the current task, including IRQ stack if any
(b) Trace the current task, but skip IRQ stack
(c) Trace some other task
In all cases, if CONFIG_FRAME_POINTER is not defined, bp should just
be 0. If it _is_ defined, then
- in case (a) bp should be gotten directly from the CPU's register, so
the caller should pass NULL for regs,
- in case (b) the caller should should pass the IRQ registers to
dump_trace(),
- in case (c) bp should be gotten from the top of the task's stack, so
the caller should pass NULL for regs.
Hence, the bp argument is not necessary because the combination of
task and regs is sufficient to determine an appropriate value for bp.
This patch introduces a new inline function stack_frame(task, regs)
that computes the desired bp. This function is then called from the
two versions of dump_stack().
Signed-off-by: Soren Sandmann <ssp@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arjan van de Ven <arjan@infradead.org>,
Cc: Frederic Weisbecker <fweisbec@gmail.com>,
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>,
LKML-Reference: <m3oc9rop28.fsf@dhcp-100-3-82.bos.redhat.com>>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
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: Don 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: Ingo Molnar <mingo@elte.hu>
Now that the KM_type stuff is history, clean up the compiler warning.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Miller <davem@davemloft.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
