While dumping a stacktrace, the end of the exception stack won't link
the frame pointer to the previous stack.
The interrupted stack will then be considered as unreliable and ignored
by perf, as the frame pointer is unreliable itself.
This happens because we overwrite the frame pointer that links to the
interrupted frame with the address of the exception stack. This is
done in order to reserve space inside.
But rbp has been chosen here only because it is not a scratch register,
so that the address of the exception stack remains in rbp after calling
do_debug(), we can then release the exception stack space without the
need to retrieve its address again.
But we can pick another non-scratch register to do that, so that we
preserve the link to the interrupted stack frame in the stacktraces.
Just randomly choose r12. Every registers are saved just before and
restored just after calling do_debug(). And r12 is not used in the
middle, which makes it a perfect candidate.
Example: perf record -g -a -c 1 -f -e mem:$(tasklist_lock_addr):rw
Before:
44.18% [k] _raw_read_lock
|
|
--- |--6.31%-- waitid
|
|--4.26%-- writev
|
|--3.63%-- __select
|
|--3.15%-- __waitpid
| |
| |--28.57%-- 0x8b52e00000139f
| |
| |--28.57%-- 0x8b52e0000013c6
| |
| |--14.29%-- 0x7fde786dc000
| |
| |--14.29%-- 0x62696c2f7273752f
| |
| --14.29%-- 0x1ea9df800000000
|
|--3.00%-- __poll
After:
43.94% [k] _raw_read_lock
|
--- _read_lock
|
|--60.53%-- send_sigio
| __kill_fasync
| kill_fasync
| evdev_pass_event
| evdev_event
| input_pass_event
| input_handle_event
| input_event
| synaptics_process_byte
| psmouse_handle_byte
| psmouse_interrupt
| serio_interrupt
| i8042_interrupt
| handle_IRQ_event
| handle_edge_irq
| handle_irq
| __irqentry_text_start
| ret_from_intr
| |
| |--30.43%-- __select
| |
| |--17.39%-- 0x454f15
| |
| |--13.04%-- __read
| |
| |--13.04%-- vread_hpet
| |
| |--13.04%-- _xcb_lock_io
| |
| --13.04%-- 0x7f630878ce87
Note: it does not only affect perf events but also other stacktraces in
x86-64. They were considered as unreliable once we quit the debug
stack frame.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: "K. Prasad" <prasad@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Dumping the callchains from breakpoint events with perf gives strange
results:
3.75% perf [kernel] [k] _raw_read_unlock
|
--- _raw_read_unlock
perf_callchain
perf_prepare_sample
__perf_event_overflow
perf_swevent_overflow
perf_swevent_add
perf_bp_event
hw_breakpoint_exceptions_notify
notifier_call_chain
__atomic_notifier_call_chain
atomic_notifier_call_chain
notify_die
do_debug
debug
munmap
We are infected with all the debug stack. Like the nmi stack, the debug
stack is undesired as it is part of the profiling path, not helpful for
the user.
Ignore it.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: "K. Prasad" <prasad@linux.vnet.ibm.com>
struct perf_event::event callback was called when a breakpoint
triggers. But this is a rather opaque callback, pretty
tied-only to the breakpoint API and not really integrated into perf
as it triggers even when we don't overflow.
We prefer to use overflow_handler() as it fits into the perf events
rules, being called only when we overflow.
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: "K. Prasad" <prasad@linux.vnet.ibm.com>
Drop the callback and task parameters from modify_user_hw_breakpoint().
For now we have no user that need to modify a breakpoint to the point
of changing its handler or its task context.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: "K. Prasad" <prasad@linux.vnet.ibm.com>
When we disable a breakpoint through dr7, we unregister it right
away, making us lose track of its corresponding address
register value.
It means that the following sequence would be unsupported:
- set address in dr0
- enable it through dr7
- disable it through dr7
- enable it through dr7
because we lost the address register value when we disabled the
breakpoint.
Don't unregister the disabled breakpoints but rather disable
them.
Reported-by: "K.Prasad" <prasad@linux.vnet.ibm.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1259735536-9236-1-git-send-regression-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In-kernel user breakpoints are created using functions in which
we pass breakpoint parameters as individual variables: address,
length and type.
Although it fits well for x86, this just does not scale across
archictectures that may support this api later as these may have
more or different needs. Pass in a perf_event_attr structure
instead because it is meant to evolve as much as possible into
a generic hardware breakpoint parameter structure.
Reported-by: K.Prasad <prasad@linux.vnet.ibm.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1259294154-5197-1-git-send-regression-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The mce_disable_cpu() and mce_reenable_cpu() are called only
from mce_cpu_callback() which is marked as __cpuinit.
So these functions can be __cpuinit too.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Andi Kleen <ak@linux.intel.com>
LKML-Reference: <4B0E3C4E.4090809@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
When we schedule out a breakpoint from the cpu, we also
incidentally remove the "Global exact breakpoint" flag from the
breakpoint control register. It makes us losing the fine grained
precision about the origin of the instructions that may trigger
breakpoint exceptions for the other breakpoints running in this
cpu.
Reported-by: Prasad <prasad@linux.vnet.ibm.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1259211878-6013-1-git-send-regression-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This simplifies the error handling when we create a breakpoint.
We don't need to check the NULL return value corner case anymore
since we have improved perf_event_create_kernel_counter() to
always return an error code in the failure case.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Prasad <prasad@linux.vnet.ibm.com>
LKML-Reference: <1259210142-5714-3-git-send-regression-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Percpu symbols now occupy the same namespace as other global
symbols and as such short global symbols without subsystem
prefix tend to collide with local variables. dr7 percpu
variable used by x86 was hit by this. Rename it to cpu_dr7.
The rename also makes it more consistent with its fellow
cpu_debugreg percpu variable.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <20091125115856.GA17856@elte.hu>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
The validate_event() was failing on valid event combinations. The
function was assuming that if x86_schedule_event() returned 0, it
meant error. But x86_schedule_event() returns the counter index and
0 is a perfectly valid value. An error is returned if the function
returns a negative value.
Furthermore, validate_event() was also failing for event groups
because the event->pmu was not set until after
hw_perf_event_init().
Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: peterz@infradead.org
Cc: paulus@samba.org
Cc: perfmon2-devel@lists.sourceforge.net
Cc: eranian@gmail.com
LKML-Reference: <4b0bdf36.1818d00a.07cc.25ae@mx.google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
--
arch/x86/kernel/cpu/perf_event.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
irq_thermal_count is only being maintained when
X86_THERMAL_VECTOR, and both X86_THERMAL_VECTOR and
X86_MCE_THRESHOLD don't need extra wrapping in X86_MCE
conditionals.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Yong Wang <yong.y.wang@intel.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Arjan van de Ven <arjan@infradead.org>
LKML-Reference: <4B06AFA902000078000211F8@vpn.id2.novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Attribute authorship to developers of hw-breakpoint related
files.
Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091123154713.GA5593@in.ibm.com>
[ v2: moved it to latest -tip ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Decreases perf overhead when function tracing is enabled,
by about 50%.
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>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Conflicts:
arch/x86/kernel/kprobes.c
kernel/trace/Makefile
Merge reason: hw-breakpoints perf integration is looking
good in testing and in reviews, plus conflicts
are mounting up - so merge & resolve.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Check objdump version before using it for insn decoder build test,
because some older objdump can't decode AVX code correctly.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Jim Keniston <jkenisto@us.ibm.com>
LKML-Reference: <20091120171314.6715.30390.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Fix postest_verbose to posttest_verbose, and add posttest_64bit option
for CONFIG_64BIT != y, since old command just passed '-' instead
of '-n' when CONFIG_64BIT is not set.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Jim Keniston <jkenisto@us.ibm.com>
LKML-Reference: <20091120171307.6715.66099.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Since some instructions are not decoded correctly by older
versions of objdump, it may cause false positive error in insn
decoder posttest.
This changes build error of insn decoder test to build warning.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
LKML-Reference: <20091116230631.5250.41579.stgit@harusame>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Show symbol name if insn decoder test find a difference.
This will help us to find out where the issue is.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
LKML-Reference: <20091116230624.5250.49813.stgit@harusame>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add verbose option to insn decoder test. This dumps decoded
instruction when building kernel with V=1.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
LKML-Reference: <20091116230618.5250.18762.stgit@harusame>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This build error:
arch/x86/kvm/x86.c:3655: error: implicit declaration of function 'hw_breakpoint_restore'
Happens because in the CONFIG_KVM=m case there's no 'CONFIG_KVM' define
in the kernel - it's CONFIG_KVM_MODULE in that case.
Make the prototype available unconditionally.
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Prasad <prasad@linux.vnet.ibm.com>
LKML-Reference: <1258114575-32655-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
arch/alpha/kernel/vmlinux.lds.S uses it:
arch/alpha/kernel/vmlinux.lds:241: undefined symbol `THREAD_SIZE' referenced in expression
Seems to have been caused by
commit 9d93f00580
Author: Geoffrey Thomas <geofft@ksplice.com>
AuthorDate: Thu Sep 24 10:36:26 2009 -0400
Commit: Linus Torvalds <torvalds@linux-foundation.org>
CommitDate: Thu Sep 24 17:16:22 2009 -0700
alpha: Clean up linker script using new linker script macros.
Note that .data.page_aligned and .data.cacheline_aligned are now after
_data; it was probably a bug that they were before it.
Also, some explicit ALIGN(8)'s between various initcall sections were
removed; this should be harmless as the implicit alignment of
initcall_t was already 8.
Cc: Geoffrey Thomas <geofft@ksplice.com>
Cc: Tim Abbott <tabbott@ksplice.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix a bug in
commit ba0a6c9f6f
Author: Peter Zijlstra <a.p.zijlstra@chello.nl>
AuthorDate: Wed Sep 23 15:57:03 2009 -0700
Commit: Linus Torvalds <torvalds@linux-foundation.org>
CommitDate: Thu Sep 24 07:21:01 2009 -0700
fcntl: add F_[SG]ETOWN_EX
In asm-generic/fcntl.h, F_SETOWN_EX and F_GETLK64 both have value 12, and
F_GETOWN_EX and F_SETLK64 both have value 13.
Reported-by: "Joseph S. Myers" <joseph@codesourcery.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Andreas Schwab <schwab@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The intel_init_thermal() is called from resume path, so it
cannot be marked as __init.
OTOH mce_banks_init() is only called from
__mcheck_cpu_cap_init() which is marked as __cpuinit, so it can
be also marked as __cpuinit.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Acked-by: Yong Wang <yong.y.wang@linux.intel.com>
LKML-Reference: <4AFBB0B8.2070501@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Adjust OMAP3 frequency transition latency from 10,000,000uS to a more
reasonable 300,000uS. This causes ondemand and conservative governors to
sample CPU load more often resulting in more responsive behavior.
Tested on Android 2.6.29; using this value and conservative governor, CORE
power consumption on Zoom2 was comparable to the old and unresponsive
10,000,000uS value while UI responsiveness was greatly improved.
Signed-off-by: Mike Turquette <mturquette@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
x86/PCI: Adjust GFP mask handling for coherent allocations
PCI ASPM: fix oops on root port removal
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc: pasemi_defconfig update
powerpc: 2.6.32 update of defconfigs for embedded 6xx/7xxx, 8xx, 8{3,5,6}xxx
powerpc/8xxx: enable IPsec ESP by default on mpc83xx/mpc85xx
powerpc/83xx: Fix u-boot partion size for MPC8377E-WLAN boards
powerpc/85xx: Fix USB GPIOs for MPC8569E-MDS boards
powerpc/82xx: kmalloc failure ignored in ep8248e_mdio_probe()
powerpc/85xx: sbc8548 - fixup of PCI-e related DTS fields
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, amd-ucode: Check UCODE_MAGIC before loading the container file
x86: Fix error return sequence in __ioremap_caller()
x86: Add Phoenix/MSC BIOSes to lowmem corruption list
This patch updates defconfig to enable options needed to properly
boot OMAP3 pandora board. It also enables MMC, OTG, GPIO LEDs,
TWL4030 GPIO and sound drivers.
Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Some drivers have dependencies on this, and therefore should be
enabled.
Signed-off-by: Sergio Aguirre <saaguirre@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
The host port power is enabled by driving the nEN_USB_PWR low as stated in
the comment. This fix is originally from Steve Sakoman <steve@sakoman.com>.
Signed-off-by: Jarkko Nikula <jhnikula@gmail.com>
Cc: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
The original TWL4030 keypad driver from linux-omap used KEY()
macro defined as (col, row), but while it was merged upstream
it was changed to use matrix keypad infrastructure, which uses
(row, col) format. Update the keymap in board file to match
layout of mainline driver.
Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
The patch provides the following fixes:
- keep kernel small enough to boot with standard tools,
- ensure compatibility with both new and legacy distros,
- turn on support for recently added or fixed hardware features.
Created and tested against linux-2.6.32-rc5.
Signed-off-by: Janusz Krzysztofik <jkrzysz@tis.icnet.pl>
Signed-off-by: Tony Lindgren <tony@atomide.com>
With CONFIG_PM=y, the omapfb/lcdc device on Amstrad Delta, after initially
starting correctly, breaks with the following error messages:
omapfb omapfb: resetting (status 0xffffff96,reset count 1)
...
omapfb omapfb: resetting (status 0xffffff96,reset count 100)
omapfb omapfb: too many reset attempts, giving up.
Looking closer at this I have found that it had been broken almost 2 years ago
with commit 2418996e3b100114edb2ae110d5d4acb928909d2, PM fixes for OMAP1.
The definite reason for broken omapfb/lcdc behavoiur in PM mode
appeared to be ARM_IDLECT1:IDLIF_ARM (bit 6) put into idle regardless of LCD
DMA possibly running. The bit were set based on return value of the
omap_dma_running() function that did not check for dedicated LCD DMA
channel status. The patch below fixes this.
Note that the hardcoded register value will be fixed during the next merge
cycle to use OMAP_LCDC_ defines. Currently the OMAP_LCDC_ defines are local
to drivers/video/omap/lcdc.c, so let's not start moving those right now.
Created against linux-2.6.32-rc6
Tested on Amstrad Delta
Signed-off-by: Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Mark the thermal init functions __init so that the init memory
can be freed.
Signed-off-by: Yong Wang <yong.y.wang@intel.com>
LKML-Reference: <20091111075125.GA17900@ywang-moblin2.bj.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
pasemi_defconfig hasn't been updated for a year.
Mostly a refresh of defaults, but this also disables 64K pages.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Use the resource_size function instead of manually calculating the
resource size. This reduces the chance of introducing off-by-one errors
and actually fixes one in mailbox.c.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Tony Lindgren <tony@atomide.com>
The bug could cause irq enable bit of one DMA channel is
cleared/set unexpectedly when 2 (or more) drivers are calling
omap_request_dma()/omap_free_dma() simultaneously
Signed-off-by: Fei Yang <AFY095@motorola.com>
Signed-off-by: Tao Hu <taohu@motorola.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Wrap in the cpu dr7 check that tells if we have active
breakpoints that need to be restored in the cpu.
This wrapper makes the check more self-explainable and also
reusable for any further other uses.
Reported-by: Jan Kiszka <jan.kiszka@web.de>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: "K. Prasad" <prasad@linux.vnet.ibm.com>
