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* perf report: Ensure the perf DSO mapping matches what libdw seesMilian Wolff2017-06-051-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In some situations the libdw unwinder stopped working properly. I.e. with libunwind we see: ~~~~~ heaptrack_gui 2228 135073.400112: 641314 cycles: e8ed _dl_fixup (/usr/lib/ld-2.25.so) 15f06 _dl_runtime_resolve_sse_vex (/usr/lib/ld-2.25.so) ed94c KDynamicJobTracker::KDynamicJobTracker (/home/milian/projects/compiled/kf5/lib64/libKF5KIOWidgets.so.5.35.0) 608f3 _GLOBAL__sub_I_kdynamicjobtracker.cpp (/home/milian/projects/compiled/kf5/lib64/libKF5KIOWidgets.so.5.35.0) f199 call_init.part.0 (/usr/lib/ld-2.25.so) f2a5 _dl_init (/usr/lib/ld-2.25.so) db9 _dl_start_user (/usr/lib/ld-2.25.so) ~~~~~ But with libdw and without this patch this sample is not properly unwound: ~~~~~ heaptrack_gui 2228 135073.400112: 641314 cycles: e8ed _dl_fixup (/usr/lib/ld-2.25.so) 15f06 _dl_runtime_resolve_sse_vex (/usr/lib/ld-2.25.so) ed94c KDynamicJobTracker::KDynamicJobTracker (/home/milian/projects/compiled/kf5/lib64/libKF5KIOWidgets.so.5.35.0) ~~~~~ Debug output showed me that libdw found a module for the last frame address, but it thinks it belongs to /usr/lib/ld-2.25.so. This patch double-checks what libdw sees and what perf knows. If the mappings mismatch, we now report the elf known to perf. This fixes the situation above, and the libdw unwinder produces the same stack as libunwind. Signed-off-by: Milian Wolff <milian.wolff@kdab.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Link: http://lkml.kernel.org/r/20170602143753.16907-1-milian.wolff@kdab.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf report: Include partial stacks unwound with libdwMilian Wolff2017-06-051-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | So far the whole stack was thrown away when any error occurred before the maximum stack depth was unwound. This is actually a very common scenario though. The stacks that got unwound so far are still interesting. This removes a large chunk of differences when comparing perf script output for libunwind and libdw perf unwinding. E.g. with libunwind: ~~~~~ heaptrack_gui 2228 135073.388524: 479408 cycles: ffffffff811749ed perf_iterate_ctx ([kernel.kallsyms]) ffffffff81181662 perf_event_mmap ([kernel.kallsyms]) ffffffff811cf5ed mmap_region ([kernel.kallsyms]) ffffffff811cfe6b do_mmap ([kernel.kallsyms]) ffffffff811b0dca vm_mmap_pgoff ([kernel.kallsyms]) ffffffff811cdb0c sys_mmap_pgoff ([kernel.kallsyms]) ffffffff81033acb sys_mmap ([kernel.kallsyms]) ffffffff81631d37 entry_SYSCALL_64_fastpath ([kernel.kallsyms]) 192ca mmap64 (/usr/lib/ld-2.25.so) 59a9 _dl_map_object_from_fd (/usr/lib/ld-2.25.so) 83d0 _dl_map_object (/usr/lib/ld-2.25.so) cda1 openaux (/usr/lib/ld-2.25.so) 1834f _dl_catch_error (/usr/lib/ld-2.25.so) cfe2 _dl_map_object_deps (/usr/lib/ld-2.25.so) 3481 dl_main (/usr/lib/ld-2.25.so) 17387 _dl_sysdep_start (/usr/lib/ld-2.25.so) 4d37 _dl_start (/usr/lib/ld-2.25.so) d87 _start (/usr/lib/ld-2.25.so) heaptrack_gui 2228 135073.388677: 611329 cycles: 1a3e0 strcmp (/usr/lib/ld-2.25.so) 82b2 _dl_map_object (/usr/lib/ld-2.25.so) cda1 openaux (/usr/lib/ld-2.25.so) 1834f _dl_catch_error (/usr/lib/ld-2.25.so) cfe2 _dl_map_object_deps (/usr/lib/ld-2.25.so) 3481 dl_main (/usr/lib/ld-2.25.so) 17387 _dl_sysdep_start (/usr/lib/ld-2.25.so) 4d37 _dl_start (/usr/lib/ld-2.25.so) d87 _start (/usr/lib/ld-2.25.so) ~~~~~ With libdw without this patch: ~~~~~ heaptrack_gui 2228 135073.388524: 479408 cycles: ffffffff811749ed perf_iterate_ctx ([kernel.kallsyms]) ffffffff81181662 perf_event_mmap ([kernel.kallsyms]) ffffffff811cf5ed mmap_region ([kernel.kallsyms]) ffffffff811cfe6b do_mmap ([kernel.kallsyms]) ffffffff811b0dca vm_mmap_pgoff ([kernel.kallsyms]) ffffffff811cdb0c sys_mmap_pgoff ([kernel.kallsyms]) ffffffff81033acb sys_mmap ([kernel.kallsyms]) ffffffff81631d37 entry_SYSCALL_64_fastpath ([kernel.kallsyms]) heaptrack_gui 2228 135073.388677: 611329 cycles: ~~~~~ With this patch applied, the libdw unwinder will produce the same output as the libunwind unwinder. Signed-off-by: Milian Wolff <milian.wolff@kdab.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Link: http://lkml.kernel.org/r/20170601210021.20046-1-milian.wolff@kdab.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf report: Fix off-by-one for non-activation framesMilian Wolff2017-05-241-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* perf tools: Move path related functions to util/path.hArnaldo Carvalho de Melo2017-04-191-0/+1
| | | | | | | | | | | | Disentangling util.h header mess a bit more. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-aj6je8ly377i4upedmjzdsq6@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf unwind: Use addr_location::addr instead of ip for entriesMilian Wolff2016-08-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fixes the srcline translation for call chains of user space applications. Before we got: perf report --stdio --no-children -s sym,srcline -g address 8.92% [.] main mandelbrot.h:41 | |--3.70%--main +8390240 | __libc_start_main +139950056726769 | _start +8388650 | |--2.74%--main +8390189 | --2.08%--main +8390296 __libc_start_main +139950056726769 _start +8388650 7.59% [.] main complex:1326 | |--4.79%--main +8390203 | __libc_start_main +139950056726769 | _start +8388650 | --2.80%--main +8390219 7.12% [.] __muldc3 libgcc2.c:1945 | |--3.76%--__muldc3 +139950060519490 | main +8390224 | __libc_start_main +139950056726769 | _start +8388650 | --3.32%--__muldc3 +139950060519512 main +8390224 With this patch applied, we instead get: perf report --stdio --no-children -s sym,srcline -g address 8.92% [.] main mandelbrot.h:41 | |--3.70%--main mandelbrot.h:41 | __libc_start_main +241 | _start +4194346 | |--2.74%--main mandelbrot.h:41 | --2.08%--main mandelbrot.h:41 __libc_start_main +241 _start +4194346 7.59% [.] main complex:1326 | |--4.79%--main complex:1326 | __libc_start_main +241 | _start +4194346 | --2.80%--main complex:1326 7.12% [.] __muldc3 libgcc2.c:1945 | |--3.76%--__muldc3 libgcc2.c:1945 | main mandelbrot.h:39 | __libc_start_main +241 | _start +4194346 | --3.32%--__muldc3 libgcc2.c:1945 main mandelbrot.h:39 Suggested-and-Acked-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Milian Wolff <milian.wolff@kdab.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> LPU-Reference: 20160816153926.11288-1-milian.wolff@kdab.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf libdw: Check for mmaps also in MAP__VARIABLE treeJiri Olsa2016-01-081-0/+10
| | | | | | | | | | | | | | We've seen cases (softice) where DWARF unwinder went through non executable mmaps, which we need to lookup in MAP__VARIABLE tree. Reported-and-Tested-by: Noel Grandin <noelgrandin@gmail.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1452158050-28061-6-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf callchain: Add order support for libdw DWARF unwinderJiri Olsa2015-11-231-15/+38
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As reported by Milian, currently for DWARF unwind (both libdw and libunwind) we display callchain in callee order only. Adding the support to follow callchain order setup to libdw DWARF unwinder, so we could get following output for report: $ perf record --call-graph dwarf ls ... $ perf report --no-children --stdio 21.12% ls libc-2.21.so [.] __strcoll_l | ---__strcoll_l mpsort_with_tmp mpsort_with_tmp mpsort_with_tmp sort_files main __libc_start_main _start $ perf report --stdio --no-children -g caller 21.12% ls libc-2.21.so [.] __strcoll_l | ---_start __libc_start_main main sort_files mpsort_with_tmp mpsort_with_tmp mpsort_with_tmp __strcoll_l Reported-and-Tested-by: Milian Wolff <milian.wolff@kdab.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Wang Nan <wangnan0@huawei.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jan Kratochvil <jkratoch@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20151119130119.GA26617@krava.brq.redhat.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf callchains: Use thread->mg->machineArnaldo Carvalho de Melo2014-10-291-2/+2
| | | | | | | | | | | | | | | | | | | | The unwind__get_entries() already receives the thread parameter, from where it can obtain the matching machine structure, shorten the signature. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Ahern <dsahern@gmail.com> Cc: Don Zickus <dzickus@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jean Pihet <jean.pihet@linaro.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-isjc6bm8mv4612mhi6af64go@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: A thread's machine can be found via thread->mg->machineArnaldo Carvalho de Melo2014-10-291-2/+2
| | | | | | | | | | | | | | | | | | | | So stop passing both machine and thread to several thread methods, reducing function signature length. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Ahern <dsahern@gmail.com> Cc: Don Zickus <dzickus@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jean Pihet <jean.pihet@linaro.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-ckcy19dcp1jfkmdihdjcqdn1@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* perf tools: Move pr_* debug macros into debug objectJiri Olsa2014-07-171-0/+1
| | | | | | | | | | | | | | | | | | Moving pr_* debug macros to have it with in same object as debug variables, becase we will change them to use verbose variable in next patch. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1405374411-29012-3-git-send-email-jolsa@kernel.org [ Add missing debug.h include in python scripting glue and in the libdw unwind lib ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* tools: Consolidate types.hBorislav Petkov2014-05-011-1/+1
| | | | | | | | | | | Combine all definitions into a common tools/include/linux/types.h and kill the wild growth elsewhere. Move DECLARE_BITMAP to its proper bitmap.h header. Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Link: http://lkml.kernel.org/n/tip-azczs7qcv6h9xek9od10hiv2@git.kernel.org Signed-off-by: Jiri Olsa <jolsa@kernel.org>
* perf tools: Add libdw DWARF post unwind supportJiri Olsa2014-02-241-0/+210
Adding libdw DWARF post unwind support, which is part of elfutils-devel/libdw-dev package from version 0.158. The new code is contained in unwin-libdw.c object, and implements unwind__get_entries unwind interface function. New Makefile variable NO_LIBDW_DWARF_UNWIND was added to control its compilation, and is marked as disabled now. It's factored with the rest of the Makefile unwind build code in the next patch. Arch specific code was added for x86. Signed-off-by: Jiri Olsa <jolsa@redhat.com> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jean Pihet <jean.pihet@linaro.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1392825179-5228-5-git-send-email-jolsa@redhat.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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