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The __hpp__sort_acc() sorts entries using callchain depth in order to
put callers above in children mode. But it assumed the callchain order
was callee-first. Now default (for children) is caller-first so the
order of entries is reverted.
For example, consider following case:
$ perf report --no-children
..l
# Overhead Command Shared Object Symbol
# ........ ....... ................... ..........................
#
99.44% a.out a.out [.] main
|
---main
__libc_start_main
_start
Then children mode should show 'start' above '__libc_start_main' since
it's the caller (parent) of the __libc_start_main. But it's reversed:
# Children Self Command Shared Object Symbol
# ........ ........ ....... ............... .....................
#
99.61% 0.00% a.out libc-2.25.so [.] __libc_start_main
99.61% 0.00% a.out a.out [.] _start
99.54% 99.44% a.out a.out [.] main
This patch fixes it.
# Children Self Command Shared Object Symbol
# ........ ........ ....... ............... .....................
#
99.61% 0.00% a.out a.out [.] _start
99.61% 0.00% a.out libc-2.25.so [.] __libc_start_main
99.54% 99.44% a.out a.out [.] main
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yao Jin <yao.jin@linux.intel.com>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170524062129.32529-8-namhyung@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The very last inlined frame, i.e. the one furthest away from the
non-inlined frame, was silently dropped. This is apparent when
comparing the output of `perf script` and `addr2line`:
~~~~~~
$ perf script --inline
...
a.out 26722 80836.309329: 72425 cycles:
21561 __hypot_finite (/usr/lib/libm-2.25.so)
ace3 hypot (/usr/lib/libm-2.25.so)
a4a main (a.out)
std::abs<double>
std::_Norm_helper<true>::_S_do_it<double>
std::norm<double>
main
20510 __libc_start_main (/usr/lib/libc-2.25.so)
bd9 _start (a.out)
$ addr2line -a -f -i -e /tmp/a.out a4a | c++filt
0x0000000000000a4a
std::__complex_abs(doublecomplex )
/usr/include/c++/6.3.1/complex:589
double std::abs<double>(std::complex<double> const&)
/usr/include/c++/6.3.1/complex:597
double std::_Norm_helper<true>::_S_do_it<double>(std::complex<double> const&)
/usr/include/c++/6.3.1/complex:654
double std::norm<double>(std::complex<double> const&)
/usr/include/c++/6.3.1/complex:664
main
/tmp/inlining.cpp:14
~~~~~
Note how `std::__complex_abs` is missing from the `perf script`
output. This is similarly showing up in `perf report`. The patch
here fixes this issue, and the output becomes:
~~~~~
a.out 26722 80836.309329: 72425 cycles:
21561 __hypot_finite (/usr/lib/libm-2.25.so)
ace3 hypot (/usr/lib/libm-2.25.so)
a4a main (a.out)
std::__complex_abs
std::abs<double>
std::_Norm_helper<true>::_S_do_it<double>
std::norm<double>
main
20510 __libc_start_main (/usr/lib/libc-2.25.so)
bd9 _start (a.out)
~~~~~
Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yao Jin <yao.jin@linux.intel.com>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170524062129.32529-7-namhyung@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
So far, the inlined nodes where only reversed when we built perf
against libbfd. If that was not available, the addr2line fallback
code path was missing the inline_list__reverse call.
Now we always add the nodes in the correct order within
inline_list__append. This removes the need to reverse the list
and also ensures that all callers construct the list in the right
order.
Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yao Jin <yao.jin@linux.intel.com>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170524062129.32529-6-namhyung@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The --inline option is to show inlined functions in callchains.
For example:
$ perf script
a.out 5644 11611.467597: 309961 cycles:u:
790 main (/home/namhyung/tmp/perf/a.out)
20511 __libc_start_main (/usr/lib/libc-2.25.so)
8ba _start (/home/namhyung/tmp/perf/a.out)
...
$ perf script --inline
a.out 5644 11611.467597: 309961 cycles:u:
790 main (/home/namhyung/tmp/perf/a.out)
std::__detail::_Adaptor<std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul>, double>::operator()
std::uniform_real_distribution<double>::operator()<std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> >
std::uniform_real_distribution<double>::operator()<std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul> >
main
20511 __libc_start_main (/usr/lib/libc-2.25.so)
8ba _start (/home/namhyung/tmp/perf/a.out)
...
Reviewed-and-tested-by: Milian Wolff <milian.wolff@kdab.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170524062129.32529-5-namhyung@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
As the documentation for dwfl_frame_pc says, frames that
are no activation frames need to have their program counter
decremented by one to properly find the function of the caller.
This fixes many cases where perf report currently attributes
the cost to the next line. I.e. I have code like this:
~~~~~~~~~~~~~~~
#include <thread>
#include <chrono>
using namespace std;
int main()
{
this_thread::sleep_for(chrono::milliseconds(1000));
this_thread::sleep_for(chrono::milliseconds(100));
this_thread::sleep_for(chrono::milliseconds(10));
return 0;
}
~~~~~~~~~~~~~~~
Now compile and record it:
~~~~~~~~~~~~~~~
g++ -std=c++11 -g -O2 test.cpp
echo 1 | sudo tee /proc/sys/kernel/sched_schedstats
perf record \
--event sched:sched_stat_sleep \
--event sched:sched_process_exit \
--event sched:sched_switch --call-graph=dwarf \
--output perf.data.raw \
./a.out
echo 0 | sudo tee /proc/sys/kernel/sched_schedstats
perf inject --sched-stat --input perf.data.raw --output perf.data
~~~~~~~~~~~~~~~
Before this patch, the report clearly shows the off-by-one issue.
Most notably, the last sleep invocation is incorrectly attributed
to the "return 0;" line:
~~~~~~~~~~~~~~~
Overhead Source:Line
........ ...........
100.00% core.c:0
|
---__schedule core.c:0
schedule
do_nanosleep hrtimer.c:0
hrtimer_nanosleep
sys_nanosleep
entry_SYSCALL_64_fastpath .tmp_entry_64.o:0
__nanosleep_nocancel .:0
std::this_thread::sleep_for<long, std::ratio<1l, 1000l> > thread:323
|
|--90.08%--main test.cpp:9
| __libc_start_main
| _start
|
|--9.01%--main test.cpp:10
| __libc_start_main
| _start
|
--0.91%--main test.cpp:13
__libc_start_main
_start
~~~~~~~~~~~~~~~
With this patch here applied, the issue is fixed. The report becomes
much more usable:
~~~~~~~~~~~~~~~
Overhead Source:Line
........ ...........
100.00% core.c:0
|
---__schedule core.c:0
schedule
do_nanosleep hrtimer.c:0
hrtimer_nanosleep
sys_nanosleep
entry_SYSCALL_64_fastpath .tmp_entry_64.o:0
__nanosleep_nocancel .:0
std::this_thread::sleep_for<long, std::ratio<1l, 1000l> > thread:323
|
|--90.08%--main test.cpp:8
| __libc_start_main
| _start
|
|--9.01%--main test.cpp:9
| __libc_start_main
| _start
|
--0.91%--main test.cpp:10
__libc_start_main
_start
~~~~~~~~~~~~~~~
Similarly it works for signal frames:
~~~~~~~~~~~~~~~
__noinline void bar(void)
{
volatile long cnt = 0;
for (cnt = 0; cnt < 100000000; cnt++);
}
__noinline void foo(void)
{
bar();
}
void sig_handler(int sig)
{
foo();
}
int main(void)
{
signal(SIGUSR1, sig_handler);
raise(SIGUSR1);
foo();
return 0;
}
~~~~~~~~~~~~~~~~
Before, the report wrongly points to `signal.c:29` after raise():
~~~~~~~~~~~~~~~~
$ perf report --stdio --no-children -g srcline -s srcline
...
100.00% signal.c:11
|
---bar signal.c:11
|
|--50.49%--main signal.c:29
| __libc_start_main
| _start
|
--49.51%--0x33a8f
raise .:0
main signal.c:29
__libc_start_main
_start
~~~~~~~~~~~~~~~~
With this patch in, the issue is fixed and we instead get:
~~~~~~~~~~~~~~~~
100.00% signal signal [.] bar
|
---bar signal.c:11
|
|--50.49%--main signal.c:29
| __libc_start_main
| _start
|
--49.51%--0x33a8f
raise .:0
main signal.c:27
__libc_start_main
_start
~~~~~~~~~~~~~~~~
Note how this patch fixes this issue for both unwinding methods, i.e.
both dwfl and libunwind. The former case is straight-forward thanks
to dwfl_frame_pc(). For libunwind, we replace the functionality via
unw_is_signal_frame() for any but the very first frame.
Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yao Jin <yao.jin@linux.intel.com>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170524062129.32529-4-namhyung@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When a filename was found in addr2line it was duplicated via strdup()
but never freed. Now we pass NULL and handle this gracefully in
addr2line.
Detected by Valgrind:
==16331== 1,680 bytes in 21 blocks are definitely lost in loss record 148 of 220
==16331== at 0x4C2AF1F: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==16331== by 0x672FA69: strdup (in /usr/lib/libc-2.25.so)
==16331== by 0x52769F: addr2line (srcline.c:256)
==16331== by 0x52769F: addr2inlines (srcline.c:294)
==16331== by 0x52769F: dso__parse_addr_inlines (srcline.c:502)
==16331== by 0x574D7A: inline__fprintf (hist.c:41)
==16331== by 0x574D7A: ipchain__fprintf_graph (hist.c:147)
==16331== by 0x57518A: __callchain__fprintf_graph (hist.c:212)
==16331== by 0x5753CF: callchain__fprintf_graph.constprop.6 (hist.c:337)
==16331== by 0x57738E: hist_entry__fprintf (hist.c:628)
==16331== by 0x57738E: hists__fprintf (hist.c:882)
==16331== by 0x44A20F: perf_evlist__tty_browse_hists (builtin-report.c:399)
==16331== by 0x44A20F: report__browse_hists (builtin-report.c:491)
==16331== by 0x44A20F: __cmd_report (builtin-report.c:624)
==16331== by 0x44A20F: cmd_report (builtin-report.c:1054)
==16331== by 0x4A49CE: run_builtin (perf.c:296)
==16331== by 0x4A4CC0: handle_internal_command (perf.c:348)
==16331== by 0x434371: run_argv (perf.c:392)
==16331== by 0x434371: main (perf.c:530)
Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yao Jin <yao.jin@linux.intel.com>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170524062129.32529-3-namhyung@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
I just hit a segfault when doing `perf report -g srcline`.
Valgrind pointed me at this code as the culprit:
==8359== Invalid read of size 8
==8359== at 0x3096D9: map__rip_2objdump (map.c:430)
==8359== by 0x2FC1A3: match_chain_srcline (callchain.c:645)
==8359== by 0x2FC1A3: match_chain (callchain.c:700)
==8359== by 0x2FC1A3: append_chain (callchain.c:895)
==8359== by 0x2FC1A3: append_chain_children (callchain.c:846)
==8359== by 0x2FF719: callchain_append (callchain.c:944)
==8359== by 0x2FF719: hist_entry__append_callchain (callchain.c:1058)
==8359== by 0x32FA06: iter_add_single_cumulative_entry (hist.c:908)
==8359== by 0x33195C: hist_entry_iter__add (hist.c:1050)
==8359== by 0x258F65: process_sample_event (builtin-report.c:204)
==8359== by 0x30D60C: perf_session__deliver_event (session.c:1310)
==8359== by 0x30D60C: ordered_events__deliver_event (session.c:119)
==8359== by 0x310D12: __ordered_events__flush (ordered-events.c:210)
==8359== by 0x310D12: ordered_events__flush.part.3 (ordered-events.c:277)
==8359== by 0x30DD3C: perf_session__process_user_event (session.c:1349)
==8359== by 0x30DD3C: perf_session__process_event (session.c:1475)
==8359== by 0x30FC3C: __perf_session__process_events (session.c:1867)
==8359== by 0x30FC3C: perf_session__process_events (session.c:1921)
==8359== by 0x25A985: __cmd_report (builtin-report.c:575)
==8359== by 0x25A985: cmd_report (builtin-report.c:1054)
==8359== by 0x2B9A80: run_builtin (perf.c:296)
==8359== Address 0x70 is not stack'd, malloc'd or (recently) free'd
This patch fixes the issue.
Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
[ Remove dependency from another change ]
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yao Jin <yao.jin@linux.intel.com>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170524062129.32529-2-namhyung@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull i2c fixes from Wolfram Sang:
"Fix the i2c-designware regression of rc2.
Also, a DMA buffer fix for the tiny-usb driver where the USB core now
loudly complains about the non DMA-capable buffer"
[ I had cherry-picked the designware fix separately because it hit my
laptop, but here is the proper sync with the i2c tree - Linus ]
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: designware: Fix bogus sda_hold_time due to uninitialized vars
i2c: i2c-tiny-usb: fix buffer not being DMA capable
Pull crypto fix from Herbert Xu:
"This fixes a regression in the skcipher interface that allows bogus
key parameters to hit underlying implementations which can cause
crashes"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: skcipher - Add missing API setkey checks
We need to initializes those variables to 0 for platforms that do not
provide ACPI parameters. Otherwise, we set sda_hold_time to random
values, breaking e.g. Galileo and IOT2000 boards.
Fixes: 9d6408433019 ("i2c: designware: don't infer timings described by ACPI from clock rate")
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Pull pstore fix from Kees Cook:
"Marta noticed another misbehavior in EFI pstore, which this fixes.
Hopefully this is the last of the v4.12 fixes for pstore!"
* tag 'pstore-v4.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
efi-pstore: Fix write/erase id tracking
The API setkey checks for key sizes and alignment went AWOL during the
skcipher conversion. This patch restores them.
Cc: <stable@vger.kernel.org>
Fixes: 4e6c3df4d729 ("crypto: skcipher - Add low-level skcipher...")
Reported-by: Baozeng <sploving1@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Since v4.9 i2c-tiny-usb generates the below call trace
and longer works, since it can't communicate with the
USB device. The reason is, that since v4.9 the USB
stack checks, that the buffer it should transfer is DMA
capable. This was a requirement since v2.2 days, but it
usually worked nevertheless.
[ 17.504959] ------------[ cut here ]------------
[ 17.505488] WARNING: CPU: 0 PID: 93 at drivers/usb/core/hcd.c:1587 usb_hcd_map_urb_for_dma+0x37c/0x570
[ 17.506545] transfer buffer not dma capable
[ 17.507022] Modules linked in:
[ 17.507370] CPU: 0 PID: 93 Comm: i2cdetect Not tainted 4.11.0-rc8+ #10
[ 17.508103] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[ 17.509039] Call Trace:
[ 17.509320] ? dump_stack+0x5c/0x78
[ 17.509714] ? __warn+0xbe/0xe0
[ 17.510073] ? warn_slowpath_fmt+0x5a/0x80
[ 17.510532] ? nommu_map_sg+0xb0/0xb0
[ 17.510949] ? usb_hcd_map_urb_for_dma+0x37c/0x570
[ 17.511482] ? usb_hcd_submit_urb+0x336/0xab0
[ 17.511976] ? wait_for_completion_timeout+0x12f/0x1a0
[ 17.512549] ? wait_for_completion_timeout+0x65/0x1a0
[ 17.513125] ? usb_start_wait_urb+0x65/0x160
[ 17.513604] ? usb_control_msg+0xdc/0x130
[ 17.514061] ? usb_xfer+0xa4/0x2a0
[ 17.514445] ? __i2c_transfer+0x108/0x3c0
[ 17.514899] ? i2c_transfer+0x57/0xb0
[ 17.515310] ? i2c_smbus_xfer_emulated+0x12f/0x590
[ 17.515851] ? _raw_spin_unlock_irqrestore+0x11/0x20
[ 17.516408] ? i2c_smbus_xfer+0x125/0x330
[ 17.516876] ? i2c_smbus_xfer+0x125/0x330
[ 17.517329] ? i2cdev_ioctl_smbus+0x1c1/0x2b0
[ 17.517824] ? i2cdev_ioctl+0x75/0x1c0
[ 17.518248] ? do_vfs_ioctl+0x9f/0x600
[ 17.518671] ? vfs_write+0x144/0x190
[ 17.519078] ? SyS_ioctl+0x74/0x80
[ 17.519463] ? entry_SYSCALL_64_fastpath+0x1e/0xad
[ 17.519959] ---[ end trace d047c04982f5ac50 ]---
Cc: <stable@vger.kernel.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Till Harbaum <till@harbaum.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>