* Re: frame-pointer based user stack unwinding with perf on arm32
2016-11-14 13:14 frame-pointer based user stack unwinding with perf on arm32 Milian Wolff
@ 2016-11-14 23:45 ` Kim Phillips
0 siblings, 0 replies; 2+ messages in thread
From: Kim Phillips @ 2016-11-14 23:45 UTC (permalink / raw)
To: Milian Wolff; +Cc: perf group
On Mon, 14 Nov 2016 14:14:30 +0100
Milian Wolff <milian.wolff@kdab.com> wrote:
Hi Milian,
> None of these produced the desired results when running `perf record -g` on
> the target platform (a panda board):
>
> root@arm:~# perf record -g ./stress_bt
> Total count: 171711327751528502
> root@arm:~# perf script
> <snip>
> ...
> stress_bt 825 7645.3346298627: 8241360 cycles:ppp:
> 5a0 foo_128+0xfffe0084 (/root/stress_bt)
>
> stress_bt 825 7645.3346305738: 7932022 cycles:ppp:
> 592 foo_128+0xfffe0076 (/root/stress_bt)
> ...
> So, can someone please clarify whether this should also work on arm32? What
> are the requirements?
I have this working with a natively-built perf (today's acme's
perf/core branch):
$ ./perf --version
perf version 4.9.rc1.g699c
$ uname -a
Linux tc2 4.8.0+ #7 SMP Tue Oct 4 10:29:55 CDT 2016 armv7l GNU/Linux
$ cat ./runcallg.sh
sudo ./perf record -o perf.data --call-graph dwarf -- ./stress_bt |& tee record-callg.log
sudo ./perf report --call-graph --stdio >& report-callg.log
$ ./runcallg.sh
Lowering default frequency rate to 1600.
Please consider tweaking /proc/sys/kernel/perf_event_max_sample_rate.
Total count: 171711327751528502
[ perf record: Woken up 514 times to write data ]
Warning:
Processed 19294 events and lost 32 chunks!
Check IO/CPU overload!
[ perf record: Captured and wrote 128.420 MB perf.data (16025 samples) ]
$ head -40 report-callg.log
Warning:
Processed 19294 events and lost 32 chunks!
Check IO/CPU overload!
# To display the perf.data header info, please use --header/--header-only options.
#
#
# Total Lost Samples: 0
#
# Samples: 16K of event 'cycles:ppp'
# Event count (approx.): 7863498267
#
# Children Self Command Shared Object Symbol
# ........ ........ ......... ................. ..................................
#
99.62% 99.58% stress_bt stress_bt [.] foo_128
|
|--95.74%--__libc_start_main
| main
| doit
| bar
| |
| |--1.01%--foo_30
| | foo_31
| | foo_32
| | foo_33
| | foo_34
| | foo_35
| | foo_36
| | foo_37
| | foo_38
| | foo_39
| | foo_40
| | foo_41
| | foo_42
| | foo_43
| | foo_44
| | foo_45
| | foo_46
The above works both with the arm32 binary included in the downloaded
stress_bt.tar.gz, and one built with a native gcc 4.9.2, using only the
'-g' flag ("gcc -g stress_bt.c").
OTOH, I tried using a cross-built perf, and it did not work (same
behaviour you're seeing).
The Linaro wiki page lists at least libunwind as a dependency, and the
native build has it:
Auto-detecting system features:
... dwarf: [ on ]
... dwarf_getlocations: [ on ]
... glibc: [ on ]
... gtk2: [ OFF ]
... libaudit: [ on ]
... libbfd: [ on ]
... libelf: [ on ]
... libnuma: [ OFF ]
... numa_num_possible_cpus: [ OFF ]
... libperl: [ on ]
... libpython: [ on ]
... libslang: [ on ]
... libcrypto: [ on ]
... libunwind: [ on ]
... libdw-dwarf-unwind: [ on ]
... zlib: [ on ]
... lzma: [ on ]
... get_cpuid: [ OFF ]
... bpf: [ OFF ]
Makefile.config:349: BPF prologue is not supported by architecture arm, missing regs_query_register_offset()
Makefile.config:422: BPF API too old. Please install recent kernel headers. BPF support in 'perf record' is disabled.
Makefile.config:519: GTK2 not found, disables GTK2 support. Please install gtk2-devel or libgtk2.0-dev
Makefile.config:693: No numa.h found, disables 'perf bench numa mem' benchmark, please install numactl-devel/libnuma-devel/libnuma-dev
whereas the cross build does not:
Auto-detecting system features:
... dwarf: [ OFF ]
... dwarf_getlocations: [ OFF ]
... glibc: [ on ]
... gtk2: [ OFF ]
... libaudit: [ OFF ]
... libbfd: [ OFF ]
... libelf: [ OFF ]
... libnuma: [ OFF ]
... numa_num_possible_cpus: [ OFF ]
... libperl: [ OFF ]
... libpython: [ OFF ]
... libslang: [ OFF ]
... libcrypto: [ OFF ]
... libunwind: [ OFF ]
... libdw-dwarf-unwind: [ OFF ]
... zlib: [ OFF ]
... lzma: [ OFF ]
... get_cpuid: [ OFF ]
... bpf: [ on ]
Makefile.config:260: No libelf found, disables 'probe' tool and BPF support in 'perf record', please install libelf-dev, l
ibelf-devel or elfutils-libelf-devel
Makefile.config:360: No sys/sdt.h found, no SDT events are defined, please install systemtap-sdt-devel or systemtap-sdt-de
v
Makefile.config:433: Disabling post unwind, no support found.
Makefile.config:479: No libaudit.h found, disables 'trace' tool, please install audit-libs-devel or libaudit-dev
Makefile.config:490: No libcrypto.h found, disables jitted code injection, please install libssl-devel or libssl-dev
Makefile.config:505: slang not found, disables TUI support. Please install slang-devel, libslang-dev or libslang2-dev
Makefile.config:519: GTK2 not found, disables GTK2 support. Please install gtk2-devel or libgtk2.0-dev
Makefile.config:547: Missing perl devel files. Disabling perl scripting support, please install perl-ExtUtils-Embed/libper
l-dev
Makefile.config:590: No 'Python.h' (for Python 2.x support) was found: disables Python support - please install python-dev
el/python-dev
Makefile.config:680: No liblzma found, disables xz kernel module decompression, please install xz-devel/liblzma-dev
Makefile.config:693: No numa.h found, disables 'perf bench numa mem' benchmark, please install numactl-devel/libnuma-devel
/libnuma-dev
Unfortunately, I don't know how to cross-build perf with libunwind
turned on: On Ubuntu, I cd tools/ and issue 'make ARCH=arm
CROSS_COMPILE=arm-linux-gnueabihf- perf'. Installing something called
android-libunwind-dev didn't help, and I can't tell whether the wiki
page includes building perf in a cross environment (in fact, it
references a /lib/arm-linux-gnueabihf/ which is present on my versatile
express' target Debian installation).
hth,
Kim
^ permalink raw reply [flat|nested] 2+ messages in thread