Don Zickus [Tue, 16 Feb 2010 22:04:52 +0000 (17:04 -0500)]
nmi_watchdog: support for oprofile
Re-arrange the code so that when someone disables nmi_watchdog
with:
echo 0 > /proc/sys/kernel/nmi_watchdog
it releases the hardware reservation on the PMUs. This allows
the oprofile module to grab those PMUs and do its thing.
Otherwise oprofile fails to load because the hardware is
reserved by the perf_events subsystem.
Tested using:
oprofile --vm-linux --start
and watched it failed when nmi_watchdog is enabled and succeed
when:
Note: this has the side quirk of having the nmi_watchdog latch
onto the software events instead of hardware events if oprofile
has already reserved the hardware first. User beware! :-)
Signed-off-by: Don Zickus <dzickus@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: gorcunov@gmail.com Cc: aris@redhat.com Cc: eranian@google.com
LKML-Reference: <1266357892-30504-1-git-send-email-dzickus@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Don Zickus [Fri, 12 Feb 2010 22:19:20 +0000 (17:19 -0500)]
nmi_watchdog: Fallback to software events when no hardware pmu detected
Not all arches have a PMU or have perf_event support for their
PMU. The nmi_watchdog will fail in those cases. Fallback to
using software events to generate nmi_watchdog traffic with
local apic interrupts.
Tested on a Pentium4 and it worked as expected, excepting for
detecting cpu lockups.
The problem with using software events as a cpu lock up detector
is the nmi_watchdog uses the logic that if local apic interrupts
stop incrementing then the cpu is probably locked up. But with
software events we use the local apic to trigger the
nmi_watchdog callback to see if local apic interrupts are still
firing, which obviously they are otherwise we wouldn't have been
triggered.
The algorithm to detect cpu lock ups is the same as the old
nmi_watchdog. Perhaps we need to find a better way to detect
lock ups?
Don Zickus [Sat, 6 Feb 2010 02:47:04 +0000 (21:47 -0500)]
nmi_watchdog: Add new, generic implementation, using perf events
This is a new generic nmi_watchdog implementation using the perf
events infrastructure as suggested by Ingo.
The implementation is simple, just create an in-kernel perf
event and register an overflow handler to check for cpu lockups.
I created a generic implementation that lives in kernel/ and
the hardware specific part that for now lives in arch/x86.
This approach has a number of advantages:
- It simplifies the x86 PMU implementation in the long run,
in that it removes the hardcoded low-level PMU implementation
that was the NMI watchdog before.
- It allows new NMI watchdog features to be added in a central
place.
- It allows other architectures to enable the NMI watchdog,
as long as they have perf events (that provide NMIs)
implemented.
- It also allows for more graceful co-existence of existing
perf events apps and the NMI watchdog - before these changes
the relationship was exclusive. (The NMI watchdog will 'spend'
a perf event when enabled. In later iterations we might be
able to piggyback from an existing NMI event without having
to allocate a hardware event for the NMI watchdog - turning
this into a no-hardware-cost feature.)
As for compatibility, we'll keep the old NMI watchdog code as
well until the new one can 100% replace it on all CPUs, old and
new alike. That might take some time as the NMI watchdog has
been ported to many CPU models.
I have done light testing to make sure the framework works
correctly and it does.
v2: Set the correct timeout values based on the old nmi
watchdog
Don Zickus [Sat, 6 Feb 2010 02:47:03 +0000 (21:47 -0500)]
x86: Move notify_die from nmi.c to traps.c
In order to handle a new nmi_watchdog approach, I need to move
the notify_die() routine out of nmi_watchdog_tick() and into
default_do_nmi(). This lets me easily swap out the old
nmi_watchdog with the new one with just a config change.
The change probably makes sense from a high level perspective
because the nmi_watchdog shouldn't be handling notify_die
routines anyway. However, this move does change the semantics a
little bit. Instead of checking on every nmi interrupt if the
cpus are stuck, only check them on the nmi_watchdog interrupts.
arch/x86/kernel/alternative.c: In function 'alternatives_text_reserved':
arch/x86/kernel/alternative.c:402: warning: comparison of distinct pointer types lacks a cast
arch/x86/kernel/alternative.c:402: warning: comparison of distinct pointer types lacks a cast
arch/x86/kernel/alternative.c:405: warning: comparison of distinct pointer types lacks a cast
arch/x86/kernel/alternative.c:405: warning: comparison of distinct pointer types lacks a cast
Kirill Smelkov [Sun, 7 Feb 2010 13:46:15 +0000 (11:46 -0200)]
perf top: Fix annotate for userspace
First, for programs and prelinked libraries, annotate code was
fooled by objdump output IPs (src->eip in the code) being
wrongly converted to absolute IPs. In such case there were no
conversion needed, but in
we were reading absolute address from objdump (e.g. 8048604) and
then almost doubling it, because eip & map->start are
approximately close for small programs.
Needless to say, that later, in record_precise_ip() there was no
matching with real runtime IPs.
And second, like with `perf annotate` the problem with
non-prelinked *.so was that we were doing rip -> objdump address
conversion wrong.
Also, because unlike `perf annotate`, `perf top` code does
annotation based on absolute IPs for performance reasons(*), new
helper for mapping objdump addresse to IP is introduced.
(*) we get samples info in absolute IPs, and since we do lots of
hit-testing on absolute IPs at runtime in record_precise_ip(), it's
better to convert objdump addresses to IPs once and do no conversion
at runtime.
I also had to fix how objdump output is parsed (with hardcoded
8/16 characters format, which was inappropriate for ET_DYN dsos
with small addresses like '4ac')
Also note, that not all objdump output lines has associtated
IPs, e.g. look at source lines here:
000004ac <my_strlen>:
extern "C"
int my_strlen(const char *s)
4ac: 55 push %ebp
4ad: 89 e5 mov %esp,%ebp
4af: 83 ec 10 sub $0x10,%esp
{
int len = 0;
4b2: c7 45 fc 00 00 00 00 movl $0x0,-0x4(%ebp)
4b9: eb 08 jmp 4c3 <my_strlen+0x17>
while (*s) {
++len;
4bb: 83 45 fc 01 addl $0x1,-0x4(%ebp)
++s;
4bf: 83 45 08 01 addl $0x1,0x8(%ebp)
So we mark them with eip=0, and ignore such lines in annotate
lookup code.
Signed-off-by: Kirill Smelkov <kirr@landau.phys.spbu.ru>
[ Note: one hunk of this patch was applied by Mike in 57d8188 ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1265550376-12665-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Since mcount function can be called from everywhere,
it should be blacklisted. Moreover, the "mcount" symbol
is a special symbol name. So, it is better to put it in
the generic blacklist.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20100205062433.3745.36726.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
We cannot assume that because hwc->idx == assign[i], we can avoid
reprogramming the counter in hw_perf_enable().
The event may have been scheduled out and another event may have been
programmed into this counter. Thus, we need a more robust way of
verifying if the counter still contains config/data related to an event.
This patch adds a generation number to each counter on each cpu. Using
this mechanism we can verify reliabilty whether the content of a counter
corresponds to an event.
Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4b66dc67.0b38560a.1635.ffffae18@mx.google.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Arjan van de Ven <arjan@linux.intel.com>
LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Check whether the address of new probe is already reserved by
ftrace or alternatives (on x86) when registering new probe.
If reserved, it returns an error and not register the probe.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: przemyslaw@pawelczyk.it Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Mathieu Desnoyers <compudj@krystal.dyndns.org> Cc: Jason Baron <jbaron@redhat.com>
LKML-Reference: <20100202214918.4694.94179.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Introducing *_text_reserved functions for checking the text
address range is partially reserved or not. This patch provides
checking routines for x86 smp alternatives and dynamic ftrace.
Since both functions modify fixed pieces of kernel text, they
should reserve and protect those from other dynamic text
modifier, like kprobes.
This will also be extended when introducing other subsystems
which modify fixed pieces of kernel text. Dynamic text modifiers
should avoid those.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: przemyslaw@pawelczyk.it Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Mathieu Desnoyers <compudj@krystal.dyndns.org> Cc: Jason Baron <jbaron@redhat.com>
LKML-Reference: <20100202214911.4694.16587.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Disable kprobe booster when CONFIG_PREEMPT=y at this time,
because it can't ensure that all kernel threads preempted on
kprobe's boosted slot run out from the slot even using
freeze_processes().
The booster on preemptive kernel will be resumed if
synchronize_tasks() or something like that is introduced.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Mathieu Desnoyers <compudj@krystal.dyndns.org> Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20100202214904.4694.24330.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Kirill Smelkov [Wed, 3 Feb 2010 18:52:08 +0000 (16:52 -0200)]
perf top: Teach it to autolocate vmlinux
By relying on logic in dso__load_kernel_sym(), we can
automatically load vmlinux.
The only thing which needs to be adjusted, is how --sym-annotate
option is handled - now we can't rely on vmlinux been loaded
until full successful pass of dso__load_vmlinux(), but that's
not the case if we'll do sym_filter_entry setup in
symbol_filter().
So move this step right after event__process_sample() where we
know the whole dso__load_kernel_sym() pass is done.
By the way, though conceptually similar `perf top` still can't
annotate userspace - see next patches with fixes.
Signed-off-by: Kirill Smelkov <kirr@landau.phys.spbu.ru> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1265223128-11786-9-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
So, if sym->start is always relative to dso mapping(*), we'll
have to unmap it for ET_EXEC like cases, and leave as is for
ET_DYN cases.
(*) and it is - we've explicitely made it relative. Look for
adjust_symbols handling in dso__load_sym()
Previously we were always unmapping sym->start and for ET_DYN
dsos resulting addresses were wrong, and so objdump output was
empty.
The end result was that perf annotate output for symbols from
non-prelinked *.so had always 0.00% percents only, which is
wrong.
To fix it, let's introduce a helper for converting rip to
objdump address, and also let's document what map_ip() and
unmap_ip() do -- I had to study sources for several hours to
understand it.
Signed-off-by: Kirill Smelkov <kirr@landau.phys.spbu.ru> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1265223128-11786-8-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
perf record: Stop intercepting events, use postprocessing to get build-ids
We want to stream events as fast as possible to perf.data, and
also in the future we want to have splice working, when no
interception will be possible.
Using build_id__mark_dso_hit_ops to create the list of DSOs that
back MMAPs we also optimize disk usage in the build-id cache by
only caching DSOs that had hits.
Suggested-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1265223128-11786-6-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
perf build-id: Move the routine to find DSOs with hits to the lib
Because 'perf record' will have to find the build-ids in after
we stop recording, so as to reduce even more the impact in the
workload while we do the measurement.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1265223128-11786-5-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
We can check using strcmp, most DSOs don't start with '[' so the
test is cheap enough and we had to test it there anyway since
when reading perf.data files we weren't calling the routine that
created this global variable and thus weren't setting it as
"loaded", which was causing a bogus:
Failed to open [vdso], continuing without symbols
Message as the first line of 'perf report'.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1265223128-11786-3-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
While debugging a problem reported by Pekka Enberg by printing
the IP and all the maps for a thread when we don't find a map
for an IP I noticed that dso__load_sym needs to fixup these
extra maps it creates to hold symbols in different ELF sections
than the main kernel one.
perf symbols: Remove perf_session usage in symbols layer
I noticed while writing the first test in 'perf regtest' that to
just test the symbol handling routines one needs to create a
perf session, that is a layer centered on a perf.data file,
events, etc, so I untied these layers.
This reduces the complexity for the users as the number of
parameters to most of the symbols and session APIs now was
reduced while not adding more state to all the map instances by
only having data that is needed to split the kernel (kallsyms
and ELF symtab sections) maps and do vmlinux relocation on the
main kernel map.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1265223128-11786-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Sun, 31 Jan 2010 07:27:58 +0000 (08:27 +0100)]
perf lock: Clean up various details
Fix up a few small stylistic details:
- use consistent vertical spacing/alignment
- remove line80 artifacts
- group some global variables better
- remove dead code
Plus rename 'prof' to 'report' to make it more in line with other
tools, and remove the line/file keying as we really want to use
IPs like the other tools do.
Hitoshi Mitake [Sat, 30 Jan 2010 11:43:32 +0000 (20:43 +0900)]
perf lock: Enhance information of lock trace events
Add wait time and lock identification details.
Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1264851813-8413-11-git-send-email-mitake@dcl.info.waseda.ac.jp>
[ removed the file/line bits as we can do that better via IPs ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch is required for making "perf lock rec" work.
The commit f5a2c3dce0 changes write_event() of builtin-record.c
. And changed write_event() sometimes doesn't stop with perf
lock rec.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
[ that commit also causes perf record to not be Ctrl-C-able,
and it's concetually wrong to parse the data at record time
(unconditionally - even when not needed), as we eventually
want to be able to do zero-copy recording, at least for
non-archive recordings. ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
perf.c: 51: ERROR: open brace '{' following function declarations go on the next line
perf.c: 73: ERROR: "foo*** bar" should be "foo ***bar"
perf.c:112: ERROR: space prohibited before that close parenthesis ')'
perf.c:127: ERROR: space prohibited before that close parenthesis ')'
perf.c:171: ERROR: "foo** bar" should be "foo **bar"
perf.c:213: ERROR: "(foo*)" should be "(foo *)"
perf.c:216: ERROR: "(foo*)" should be "(foo *)"
perf.c:217: ERROR: space required before that '*' (ctx:OxV)
perf.c:452: ERROR: do not initialise statics to 0 or NULL
perf.c:453: ERROR: do not initialise statics to 0 or NULL
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Masami Hiramatsu <mhiramat@redhat.com>
LKML-Reference: <1264633557-17597-7-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
perf top: Exit if specified --vmlinux can't be used
As we do lazy loading of symtabs we only will know if the
specified vmlinux file is invalid when we actually have a hit in
kernel space and then try to load it. So if we get kernel hits
and there are _no_ symbols in the DSO backing the kernel map,
bail out.
Reported-by: Mike Galbraith <efault@gmx.de> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1264633557-17597-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Fri, 29 Jan 2010 08:04:26 +0000 (09:04 +0100)]
perf_events: Fix sample_period transfer on inherit
One problem with frequency driven counters is that we cannot
predict the rate at which they trigger, therefore we have to
start them at period=1, this causes a ramp up effect. However,
if we fail to propagate the stable state on fork each new child
will have to ramp up again. This can lead to significant
artifacts in sample data.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: eranian@google.com Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1264752266.4283.2121.camel@laptop> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Wed, 27 Jan 2010 22:07:49 +0000 (23:07 +0100)]
perf_events, x86: Remove spurious counter reset from x86_pmu_enable()
At enable time the counter might still have a ->idx pointing to
a previously occupied location that might now be taken by
another event. Resetting the counter at that location with data
from this event will destroy the other counter's count.
Peter Zijlstra [Wed, 27 Jan 2010 22:07:48 +0000 (23:07 +0100)]
perf_events, x86: Implement Intel Westmere support
The new Intel documentation includes Westmere arch specific
event maps that are significantly different from the Nehalem
ones. Add support for this generation.
Found the CPUID model numbers on wikipedia.
Also ammend some Nehalem constraints, spotted those when looking
for the differences between Nehalem and Westmere.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <20100127221122.151865645@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Fri, 22 Jan 2010 14:59:29 +0000 (15:59 +0100)]
bitops: Provide compile time HWEIGHT{8,16,32,64}
Provide compile time versions of hweight.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <20100122155535.797688466@chello.nl>
[ Remove some whitespace damage while we are at it ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
Stephane Eranian [Mon, 18 Jan 2010 08:58:01 +0000 (10:58 +0200)]
perf_events, x86: Improve x86 event scheduling
This patch improves event scheduling by maximizing the use of PMU
registers regardless of the order in which events are created in a group.
The algorithm takes into account the list of counter constraints for each
event. It assigns events to counters from the most constrained, i.e.,
works on only one counter, to the least constrained, i.e., works on any
counter.
Intel Fixed counter events and the BTS special event are also handled via
this algorithm which is designed to be fairly generic.
The patch also updates the validation of an event to use the scheduling
algorithm. This will cause early failure in perf_event_open().
The 2nd version of this patch follows the model used by PPC, by running
the scheduling algorithm and the actual assignment separately. Actual
assignment takes place in hw_perf_enable() whereas scheduling is
implemented in hw_perf_group_sched_in() and x86_pmu_enable().
Signed-off-by: Stephane Eranian <eranian@google.com>
[ fixup whitespace and style nits as well as adding is_x86_event() ] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4b5430c6.0f975e0a.1bf9.ffff85fe@mx.google.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
K.Prasad [Thu, 28 Jan 2010 11:14:01 +0000 (16:44 +0530)]
x86/debug: Clear reserved bits of DR6 in do_debug()
Clear the reserved bits from the stored copy of debug status
register (DR6).
This will help easy bitwise operations such as quick testing
of a debug event origin.
Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Roland McGrath <roland@redhat.com> Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <20100128111401.GB13935@in.ibm.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Xiao Guangrong [Thu, 28 Jan 2010 01:32:29 +0000 (09:32 +0800)]
perf: Factorize trace events raw sample buffer operations
Introduce ftrace_perf_buf_prepare() and ftrace_perf_buf_submit() to
gather the common code that operates on raw events sampling buffer.
This cleans up redundant code between regular trace events, syscall
events and kprobe events.
Changelog v1->v2:
- Rename function name as per Masami and Frederic's suggestion
- Add __kprobes for ftrace_perf_buf_prepare() and make
ftrace_perf_buf_submit() inline as per Masami's suggestion
- Export ftrace_perf_buf_prepare since modules will use it
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Jason Baron <jbaron@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4B60E92D.9000808@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
It turns out the backtrace code has a check for the idle task and the IP
sampling does not. This creates problems when profiling an interrupt
heavy workload (in my case 10Gbit ethernet) since we get no backtraces
for interrupts received while idle (ie most of the workload).
Right now x86 and sh check that current is not NULL, which should never
happen so remove that too.
Idle task's exclusion must be performed from the core code, on top
of perf_event_attr:exclude_idle.
Signed-off-by: Anton Blanchard <anton@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mundt <lethal@linux-sh.org>
LKML-Reference: <20100118054707.GT12666@kryten> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
hw_breakpoints: Release the bp slot if arch_validate_hwbkpt_settings() fails.
On a given architecture, when hardware breakpoint registration fails
due to un-supported access type (read/write/execute), we lose the bp
slot since register_perf_hw_breakpoint() does not release the bp slot
on failure.
Hence, any subsequent hardware breakpoint registration starts failing
with 'no space left on device' error.
This patch introduces error handling in register_perf_hw_breakpoint()
function and releases bp slot on error.
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: K. Prasad <prasad@linux.vnet.ibm.com> Cc: Maneesh Soni <maneesh@in.ibm.com>
LKML-Reference: <20100121125516.GA32521@in.ibm.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
perf symbols: Use the right variable to check for kallsyms in the cache
Probably this wasn't noticed when testing this on my parisc
machine because I must have copied manually to its cache the
vmlinux file used in the x86_64 machine, now that I tried
looking on a x86-32 machine with a fresh cache, kernel symbols
weren't being resolved even with the right kallsyms copy on its
cache, duh.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1264178102-4203-2-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Tue, 26 Jan 2010 17:50:16 +0000 (18:50 +0100)]
perf: Reimplement frequency driven sampling
There was a bug in the old period code that caused intel_pmu_enable_all()
or native_write_msr_safe() to show up quite high in the profiles.
In staring at that code it made my head hurt, so I rewrote it in a
hopefully simpler fashion. Its now fully symetric between tick and
overflow driven adjustments and uses less data to boot.
The only complication is that it basically wants to do a u128 division.
The code approximates that in a rather simple truncate until it fits
fashion, taking care to balance the terms while truncating.
This version does not generate that sampling artefact.
fnctl: f_modown should call write_lock_irqsave/restore
Commit 703625118069f9f8960d356676662d3db5a9d116 exposed that f_modown()
should call write_lock_irqsave instead of just write_lock_irq so that
because a caller could have a spinlock held and it would not be good to
renable interrupts.
Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Tavis Ormandy <taviso@google.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Tue, 26 Jan 2010 03:05:06 +0000 (19:05 -0800)]
Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: Drop EXT4_GET_BLOCKS_UPDATE_RESERVE_SPACE flag
ext4: Fix quota accounting error with fallocate
ext4: Handle -EDQUOT error on write
Linus Torvalds [Tue, 26 Jan 2010 03:03:45 +0000 (19:03 -0800)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
ASoC: fix a memory-leak in wm8903
ALSA: hda - add possibility to choose speakers configuration for 4930g
ALSA: hda - Fix HP T5735 automute
ALSA: hda - Turn on EAPD only if available for Realtek codecs
ALSA: hda - Fix parsing pin node 0x21 on ALC259
Linus Torvalds [Tue, 26 Jan 2010 03:02:31 +0000 (19:02 -0800)]
Merge branch 'kvm-updates/2.6.33' of git://git.kernel.org/pub/scm/virt/kvm/kvm
* 'kvm-updates/2.6.33' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: x86: Fix leak of free lapic date in kvm_arch_vcpu_init()
KVM: x86: Fix probable memory leak of vcpu->arch.mce_banks
KVM: S390: fix potential array overrun in intercept handling
KVM: fix spurious interrupt with irqfd
eventfd - allow atomic read and waitqueue remove
KVM: MMU: bail out pagewalk on kvm_read_guest error
KVM: properly check max PIC pin in irq route setup
KVM: only allow one gsi per fd
KVM: x86: Fix host_mapping_level()
KVM: powerpc: Show timing option only on embedded
KVM: Fix race between APIC TMR and IRR
Linus Torvalds [Tue, 26 Jan 2010 03:02:06 +0000 (19:02 -0800)]
Merge branch 'linux-next' of git://git.infradead.org/ubi-2.6
* 'linux-next' of git://git.infradead.org/ubi-2.6:
UBI: fix memory leak in update path
UBI: add more checks to chdev open
UBI: initialise update marker
Linus Torvalds [Tue, 26 Jan 2010 03:00:56 +0000 (19:00 -0800)]
Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging
* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
hwmon: (fschmd) Fix a memleak on multiple opens of /dev/watchdog
hwmon: (asus_atk0110) Do not fail if MBIF is missing
hwmon: (amc6821) Double unlock bug
hwmon: (smsc47m1) Fix section mismatch
Linus Torvalds [Tue, 26 Jan 2010 02:59:47 +0000 (18:59 -0800)]
Merge branch 'drm-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6
* 'drm-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6: (95 commits)
drm/radeon/kms: preface warning printk with driver name
drm/radeon/kms: drop unnecessary printks.
drm: fix regression in fb blank handling
drm/radeon/kms: make hibernate work on IGPs
drm/vmwgfx: Optimize memory footprint for DMA buffers.
drm/ttm: Allow system memory as a busy placement.
drm/ttm: Fix race condition in ttm_bo_delayed_delete (v3, final)
drm/nv50: prevent switching off SOR when in use for DVI-over-DP
drm/nv50: fail auxch transaction if reply count not what we expect
drm/nouveau: fix failure path if userspace specifies no valid memtypes
drm/nouveau: report LVDS as disconnected if lid closed
drm/radeon/kms: fix legacy get_engine/memory clock
drm/radeon/kms/atom: atom parser fixes
drm/radeon/kms: clean up atombios pll code
drm/radeon/kms: clean up pll struct
drm/radeon/kms/atom: fix crtc lock ordering
drm/radeon: r6xx/r7xx possible security issue, system ram access
drm/radeon/kms: r600/r700 don't test ib if ib initialization fails
drm/radeon/kms: Forbid creation of framebuffer with no valid GEM object
drm/radeon/kms: r600 handle irq vector ring overflow
...
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (42 commits)
virtio_net: Make delayed refill more reliable
sfc: Use fixed-size buffers for MCDI NVRAM requests
sfc: Add workspace for GMAC bug workaround to MCDI MAC_STATS buffer
tcp_probe: avoid modulus operation and wrap fix
qlge: Only free resources if they were allocated
netns xfrm: deal with dst entries in netns
sky2: revert config space change
vlan: fix vlan_skb_recv()
netns xfrm: fix "ip xfrm state|policy count" misreport
sky2: Enable/disable WOL per hardware device
net: Fix IPv6 GSO type checks in Intel ethernet drivers
igb/igbvf: cleanup exception handling in tx_map_adv
MAINTAINERS: Add Intel igbvf maintainer
e1000/e1000e: don't use small hardware rx buffers
fmvj18x_cs: add new id (Panasonic lan & modem card)
be2net: swap only first 2 fields of mcc_wrb
Please add support for Microsoft MN-120 PCMCIA network card
be2net: fix bug in rx page posting
wimax/i2400m: Add support for more i6x50 SKUs
e1000e: enhance frame fragment detection
...
Linus Torvalds [Tue, 26 Jan 2010 02:56:12 +0000 (18:56 -0800)]
Merge branch 'omap-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6
* 'omap-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6: (25 commits)
OMAP2/3: DMTIMER: Clear pending interrupts when stopping a timer
PM debug: Fix warning when no CONFIG_DEBUG_FS
OMAP3: PM: DSS PM_WKEN to refill DMA
OMAP: timekeeping: time should not stop during suspend
OMAP3: PM: Force write last pad config register into save area
OMAP: omap3_pm_get_suspend_state() error ignored in pwrdm_suspend_get()
OMAP3: PM: Enable wake-up from McBSP2, 3 and 4 modules
OMAP3: PM debug: fix build error when !CONFIG_DEBUG_FS
OMAP3: PM: Removing redundant and potentially dangerous PRCM configration
OMAP3: Fixed ARM aux ctrl register save/restore
OMAP3: CPUidle: Fixed timer resolution
OMAP3: PM: Remove duplicate code blocks
OMAP3: PM: Disable interrupt controller AUTOIDLE before WFI
OMAP3: PM: Enable system control module autoidle
OMAP3: PM: Ack pending interrupts before entering suspend
omap: Enable GPMC clock in gpmc_init
OMAP1 clock: fix for "BUG: spinlock lockup on CPU#0"
OMAP4: clocks: Fix the clksel_rate struct DPLL divs
OMAP4: PRCM: Fix the base address for CHIRONSS reg defines
OMAP: dma_chan[lch_head].flag & OMAP_DMA_ACTIVE tested twice in omap_dma_unlink_lch()
...
Herbert Xu [Mon, 25 Jan 2010 23:51:01 +0000 (15:51 -0800)]
virtio_net: Make delayed refill more reliable
I have seen RX stalls on a machine that experienced a suspected
OOM. After the stall, the RX buffer is empty on the guest side
and there are exactly 16 entries available on the host side. As
the number of entries is less than that required by a maximal
skb, the host cannot proceed.
The guest did not have a refill job scheduled.
My diagnosis is that an OOM had occured, with the delayed refill
job scheduled. The job was able to allocate at least one skb, but
not enough to overcome the minimum required by the host to proceed.
As the refill job would only reschedule itself if it failed completely
to allocate any skbs, this would lead to an RX stall.
The following patch removes this stall possibility by always
rescheduling the refill job until the ring is totally refilled.
Testing has shown that the RX stall no longer occurs whereas
previously it would occur within a day.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Ben Hutchings [Mon, 25 Jan 2010 23:49:59 +0000 (15:49 -0800)]
sfc: Use fixed-size buffers for MCDI NVRAM requests
The low-level MCDI code always uses 32-bit MMIO operations, and
callers must pad input and output buffers to multiples of 4 bytes.
The MCDI NVRAM functions are not doing this. Also, their buffers are
declared as variable-length arrays with no explicit maximum length.
Switch to a fixed buffer size based on the chunk size used by the
MTD driver (which is a multiple of 4).
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Guido Barzini [Mon, 25 Jan 2010 23:49:19 +0000 (15:49 -0800)]
sfc: Add workspace for GMAC bug workaround to MCDI MAC_STATS buffer
Due to a hardware bug in the SFC9000 family, the firmware must
transfer raw GMAC statistics to host memory before aggregating them
into the cooked (speed-independent) MAC statistics. Extend the stats
buffer to support this.
The length of the buffer is explicit in the MAC_STATS command, so this
change is backward-compatible on both sides.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
By rounding up the buffer size to power of 2, several expensive
modulus operations can be avoided. This patch also solves a bug where
the gap need when ring gets full was not being accounted for.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Wei Yongjun [Fri, 22 Jan 2010 06:21:29 +0000 (14:21 +0800)]
KVM: x86: Fix leak of free lapic date in kvm_arch_vcpu_init()
In function kvm_arch_vcpu_init(), if the memory malloc for
vcpu->arch.mce_banks is fail, it does not free the memory
of lapic date. This patch fixed it.
Wei Yongjun [Fri, 22 Jan 2010 06:18:47 +0000 (14:18 +0800)]
KVM: x86: Fix probable memory leak of vcpu->arch.mce_banks
vcpu->arch.mce_banks is malloc in kvm_arch_vcpu_init(), but
never free in any place, this may cause memory leak. So this
patch fixed to free it in kvm_arch_vcpu_uninit().
KVM: S390: fix potential array overrun in intercept handling
kvm_handle_sie_intercept uses a jump table to get the intercept handler
for a SIE intercept. Static code analysis revealed a potential problem:
the intercept_funcs jump table was defined to contain (0x48 >> 2) entries,
but we only checked for code > 0x48 which would cause an off-by-one
array overflow if code == 0x48.
Use the compiler and ARRAY_SIZE to automatically set the limits.
Cc: stable@kernel.org Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
projects / linux-beck.git / log