Commit Graph

22 Commits

Author SHA1 Message Date
Milian Wolff
1fe627da30 perf unwind: Take pgoff into account when reporting elf to libdwfl
libdwfl parses an ELF file itself and creates mappings for the
individual sections. perf on the other hand sees raw mmap events which
represent individual sections. When we encounter an address pointing
into a mapping with pgoff != 0, we must take that into account and
report the file at the non-offset base address.

This fixes unwinding with libdwfl in some cases. E.g. for a file like:

```

using namespace std;

mutex g_mutex;

double worker()
{
    lock_guard<mutex> guard(g_mutex);
    uniform_real_distribution<double> uniform(-1E5, 1E5);
    default_random_engine engine;
    double s = 0;
    for (int i = 0; i < 1000; ++i) {
        s += norm(complex<double>(uniform(engine), uniform(engine)));
    }
    cout << s << endl;
    return s;
}

int main()
{
    vector<std::future<double>> results;
    for (int i = 0; i < 10000; ++i) {
        results.push_back(async(launch::async, worker));
    }
    return 0;
}
```

Compile it with `g++ -g -O2 -lpthread cpp-locking.cpp  -o cpp-locking`,
then record it with `perf record --call-graph dwarf -e
sched:sched_switch`.

When you analyze it with `perf script` and libunwind, you should see:

```
cpp-locking 20038 [005] 54830.236589: sched:sched_switch: prev_comm=cpp-locking prev_pid=20038 prev_prio=120 prev_state=T ==> next_comm=swapper/5 next_pid=0 next_prio=120
        ffffffffb166fec5 __sched_text_start+0x545 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb166fec5 __sched_text_start+0x545 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1670208 schedule+0x28 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb16737cc rwsem_down_read_failed+0xec (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1665e04 call_rwsem_down_read_failed+0x14 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1672a03 down_read+0x13 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb106bd85 __do_page_fault+0x445 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb18015f5 page_fault+0x45 (/lib/modules/4.14.78-1-lts/build/vmlinux)
            7f38e4252591 new_heap+0x101 (/usr/lib/libc-2.28.so)
            7f38e4252d0b arena_get2.part.4+0x2fb (/usr/lib/libc-2.28.so)
            7f38e4255b1c tcache_init.part.6+0xec (/usr/lib/libc-2.28.so)
            7f38e42569e5 __GI___libc_malloc+0x115 (inlined)
            7f38e4241790 __GI__IO_file_doallocate+0x90 (inlined)
            7f38e424fbbf __GI__IO_doallocbuf+0x4f (inlined)
            7f38e424ee47 __GI__IO_file_overflow+0x197 (inlined)
            7f38e424df36 _IO_new_file_xsputn+0x116 (inlined)
            7f38e4242bfb __GI__IO_fwrite+0xdb (inlined)
            7f38e463fa6d std::basic_streambuf<char, std::char_traits<char> >::sputn(char const*, long)+0x1cd (inlined)
            7f38e463fa6d std::ostreambuf_iterator<char, std::char_traits<char> >::_M_put(char const*, long)+0x1cd (inlined)
            7f38e463fa6d std::ostreambuf_iterator<char, std::char_traits<char> > std::__write<char>(std::ostreambuf_iterator<char, std::char_traits<char> >, char const*, int)+0x1cd (inlined)
            7f38e463fa6d std::ostreambuf_iterator<char, std::char_traits<char> > std::num_put<char, std::ostreambuf_iterator<char, std::char_traits<char> > >::_M_insert_float<double>(std::ostreambuf_iterator<c>
            7f38e464bd70 std::num_put<char, std::ostreambuf_iterator<char, std::char_traits<char> > >::put(std::ostreambuf_iterator<char, std::char_traits<char> >, std::ios_base&, char, double) const+0x90 (inl>
            7f38e464bd70 std::ostream& std::ostream::_M_insert<double>(double)+0x90 (/usr/lib/libstdc++.so.6.0.25)
            563b9cb502f7 std::ostream::operator<<(double)+0xb7 (inlined)
            563b9cb502f7 worker()+0xb7 (/ssd/milian/projects/kdab/rnd/hotspot/build/tests/test-clients/cpp-locking/cpp-locking)
            563b9cb506fb double std::__invoke_impl<double, double (*)()>(std::__invoke_other, double (*&&)())+0x2b (inlined)
            563b9cb506fb std::__invoke_result<double (*)()>::type std::__invoke<double (*)()>(double (*&&)())+0x2b (inlined)
            563b9cb506fb decltype (__invoke((_S_declval<0ul>)())) std:🧵:_Invoker<std::tuple<double (*)()> >::_M_invoke<0ul>(std::_Index_tuple<0ul>)+0x2b (inlined)
            563b9cb506fb std:🧵:_Invoker<std::tuple<double (*)()> >::operator()()+0x2b (inlined)
            563b9cb506fb std::__future_base::_Task_setter<std::unique_ptr<std::__future_base::_Result<double>, std::__future_base::_Result_base::_Deleter>, std:🧵:_Invoker<std::tuple<double (*)()> >, dou>
            563b9cb506fb std::_Function_handler<std::unique_ptr<std::__future_base::_Result_base, std::__future_base::_Result_base::_Deleter> (), std::__future_base::_Task_setter<std::unique_ptr<std::__future_>
            563b9cb507e8 std::function<std::unique_ptr<std::__future_base::_Result_base, std::__future_base::_Result_base::_Deleter> ()>::operator()() const+0x28 (inlined)
            563b9cb507e8 std::__future_base::_State_baseV2::_M_do_set(std::function<std::unique_ptr<std::__future_base::_Result_base, std::__future_base::_Result_base::_Deleter> ()>*, bool*)+0x28 (/ssd/milian/>
            7f38e46d24fe __pthread_once_slow+0xbe (/usr/lib/libpthread-2.28.so)
            563b9cb51149 __gthread_once+0xe9 (inlined)
            563b9cb51149 void std::call_once<void (std::__future_base::_State_baseV2::*)(std::function<std::unique_ptr<std::__future_base::_Result_base, std::__future_base::_Result_base::_Deleter> ()>*, bool*)>
            563b9cb51149 std::__future_base::_State_baseV2::_M_set_result(std::function<std::unique_ptr<std::__future_base::_Result_base, std::__future_base::_Result_base::_Deleter> ()>, bool)+0xe9 (inlined)
            563b9cb51149 std::__future_base::_Async_state_impl<std:🧵:_Invoker<std::tuple<double (*)()> >, double>::_Async_state_impl(std:🧵:_Invoker<std::tuple<double (*)()> >&&)::{lambda()#1}::op>
            563b9cb51149 void std::__invoke_impl<void, std::__future_base::_Async_state_impl<std:🧵:_Invoker<std::tuple<double (*)()> >, double>::_Async_state_impl(std:🧵:_Invoker<std::tuple<double>
            563b9cb51149 std::__invoke_result<std::__future_base::_Async_state_impl<std:🧵:_Invoker<std::tuple<double (*)()> >, double>::_Async_state_impl(std:🧵:_Invoker<std::tuple<double (*)()> >>
            563b9cb51149 decltype (__invoke((_S_declval<0ul>)())) std:🧵:_Invoker<std::tuple<std::__future_base::_Async_state_impl<std:🧵:_Invoker<std::tuple<double (*)()> >, double>::_Async_state_>
            563b9cb51149 std:🧵:_Invoker<std::tuple<std::__future_base::_Async_state_impl<std:🧵:_Invoker<std::tuple<double (*)()> >, double>::_Async_state_impl(std:🧵:_Invoker<std::tuple<dou>
            563b9cb51149 std:🧵:_State_impl<std:🧵:_Invoker<std::tuple<std::__future_base::_Async_state_impl<std:🧵:_Invoker<std::tuple<double (*)()> >, double>::_Async_state_impl(std::thread>
            7f38e45f0062 execute_native_thread_routine+0x12 (/usr/lib/libstdc++.so.6.0.25)
            7f38e46caa9c start_thread+0xfc (/usr/lib/libpthread-2.28.so)
            7f38e42ccb22 __GI___clone+0x42 (inlined)
```

Before this patch, using libdwfl, you would see:

```
cpp-locking 20038 [005] 54830.236589: sched:sched_switch: prev_comm=cpp-locking prev_pid=20038 prev_prio=120 prev_state=T ==> next_comm=swapper/5 next_pid=0 next_prio=120
        ffffffffb166fec5 __sched_text_start+0x545 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb166fec5 __sched_text_start+0x545 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1670208 schedule+0x28 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb16737cc rwsem_down_read_failed+0xec (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1665e04 call_rwsem_down_read_failed+0x14 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1672a03 down_read+0x13 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb106bd85 __do_page_fault+0x445 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb18015f5 page_fault+0x45 (/lib/modules/4.14.78-1-lts/build/vmlinux)
            7f38e4252591 new_heap+0x101 (/usr/lib/libc-2.28.so)
        a041161e77950c5c [unknown] ([unknown])
```

With this patch applied, we get a bit further in unwinding:

```
cpp-locking 20038 [005] 54830.236589: sched:sched_switch: prev_comm=cpp-locking prev_pid=20038 prev_prio=120 prev_state=T ==> next_comm=swapper/5 next_pid=0 next_prio=120
        ffffffffb166fec5 __sched_text_start+0x545 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb166fec5 __sched_text_start+0x545 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1670208 schedule+0x28 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb16737cc rwsem_down_read_failed+0xec (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1665e04 call_rwsem_down_read_failed+0x14 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb1672a03 down_read+0x13 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb106bd85 __do_page_fault+0x445 (/lib/modules/4.14.78-1-lts/build/vmlinux)
        ffffffffb18015f5 page_fault+0x45 (/lib/modules/4.14.78-1-lts/build/vmlinux)
            7f38e4252591 new_heap+0x101 (/usr/lib/libc-2.28.so)
            7f38e4252d0b arena_get2.part.4+0x2fb (/usr/lib/libc-2.28.so)
            7f38e4255b1c tcache_init.part.6+0xec (/usr/lib/libc-2.28.so)
            7f38e42569e5 __GI___libc_malloc+0x115 (inlined)
            7f38e4241790 __GI__IO_file_doallocate+0x90 (inlined)
            7f38e424fbbf __GI__IO_doallocbuf+0x4f (inlined)
            7f38e424ee47 __GI__IO_file_overflow+0x197 (inlined)
            7f38e424df36 _IO_new_file_xsputn+0x116 (inlined)
            7f38e4242bfb __GI__IO_fwrite+0xdb (inlined)
            7f38e463fa6d std::basic_streambuf<char, std::char_traits<char> >::sputn(char const*, long)+0x1cd (inlined)
            7f38e463fa6d std::ostreambuf_iterator<char, std::char_traits<char> >::_M_put(char const*, long)+0x1cd (inlined)
            7f38e463fa6d std::ostreambuf_iterator<char, std::char_traits<char> > std::__write<char>(std::ostreambuf_iterator<char, std::char_traits<char> >, char const*, int)+0x1cd (inlined)
            7f38e463fa6d std::ostreambuf_iterator<char, std::char_traits<char> > std::num_put<char, std::ostreambuf_iterator<char, std::char_traits<char> > >::_M_insert_float<double>(std::ostreambuf_iterator<c>
            7f38e464bd70 std::num_put<char, std::ostreambuf_iterator<char, std::char_traits<char> > >::put(std::ostreambuf_iterator<char, std::char_traits<char> >, std::ios_base&, char, double) const+0x90 (inl>
            7f38e464bd70 std::ostream& std::ostream::_M_insert<double>(double)+0x90 (/usr/lib/libstdc++.so.6.0.25)
            563b9cb502f7 std::ostream::operator<<(double)+0xb7 (inlined)
            563b9cb502f7 worker()+0xb7 (/ssd/milian/projects/kdab/rnd/hotspot/build/tests/test-clients/cpp-locking/cpp-locking)
        6eab825c1ee3e4ff [unknown] ([unknown])
```

Note that the backtrace is still stopping too early, when compared to
the nice results obtained via libunwind. It's unclear so far what the
reason for that is.

Committer note:

Further comment by Milian on the thread started on the Link: tag below:

 ---
The remaining issue is due to a bug in elfutils:

https://sourceware.org/ml/elfutils-devel/2018-q4/msg00089.html

With both patches applied, libunwind and elfutils produce the same output for
the above scenario.
 ---

Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20181029141644.3907-1-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-10-31 09:57:50 -03:00
Sandipan Das
2a9d5050dc perf script: Show correct offsets for DWARF-based unwinding
When perf/data is recorded with the dwarf call-graph option, the
callchain shown by 'perf script' still shows the binary offsets of the
userspace symbols instead of their virtual addresses. Since the symbol
offset calculation is based on using virtual address as the ip, we see
incorrect offsets as well.

The use of virtual addresses affects the ability to find out the
line number in the corresponding source file to which an address
maps to as described in commit 6754075915 ("perf unwind: Use
addr_location::addr instead of ip for entries").

This has also been addressed by temporarily converting the virtual
address to the correponding binary offset so that it can be mapped
to the source line number correctly.

This is a follow-up for commit 1961018469 ("perf script: Show
virtual addresses instead of offsets").

This can be verified on a powerpc64le system running Fedora 27 as
shown below:

  # perf probe -x /usr/lib64/libc-2.26.so -a inet_pton
  # perf record -e probe_libc:inet_pton --call-graph=dwarf ping -6 -c 1 ::1

Before:

  # perf report --stdio --no-children -s sym,srcline -g address

  # Samples: 1  of event 'probe_libc:inet_pton'
  # Event count (approx.): 1
  #
  # Overhead  Symbol                Source:Line
  # ........  ....................  ...........
  #
     100.00%  [.] __GI___inet_pton  inet_pton.c
              |
              ---gaih_inet getaddrinfo.c:537 (inlined)
                 __GI_getaddrinfo getaddrinfo.c:2304 (inlined)
                 main ping.c:519
                 generic_start_main libc-start.c:308 (inlined)
                 __libc_start_main libc-start.c:102
  ...

  # perf script -F comm,ip,sym,symoff,srcline,dso

  ping
                    15af28 __GI___inet_pton+0xffff000099160008 (/usr/lib64/libc-2.26.so)
    libc-2.26.so[ffff80004ca0af28]
                    10fa53 gaih_inet+0xffff000099160f43
    libc-2.26.so[ffff80004c9bfa53] (inlined)
                    1105b3 __GI_getaddrinfo+0xffff000099160163
    libc-2.26.so[ffff80004c9c05b3] (inlined)
                      2d6f main+0xfffffffd9f1003df (/usr/bin/ping)
    ping[fffffffecf882d6f]
                     2369f generic_start_main+0xffff00009916013f
    libc-2.26.so[ffff80004c8d369f] (inlined)
                     23897 __libc_start_main+0xffff0000991600b7 (/usr/lib64/libc-2.26.so)
    libc-2.26.so[ffff80004c8d3897]

After:

  # perf report --stdio --no-children -s sym,srcline -g address

  # Samples: 1  of event 'probe_libc:inet_pton'
  # Event count (approx.): 1
  #
  # Overhead  Symbol                Source:Line
  # ........  ....................  ...........
  #
     100.00%  [.] __GI___inet_pton  inet_pton.c
              |
              ---gaih_inet.constprop.7 getaddrinfo.c:537
                 getaddrinfo getaddrinfo.c:2304
                 main ping.c:519
                 generic_start_main.isra.0 libc-start.c:308
                 __libc_start_main libc-start.c:102
  ...

  # perf script -F comm,ip,sym,symoff,srcline,dso

  ping
              7fffb38aaf28 __GI___inet_pton+0x8 (/usr/lib64/libc-2.26.so)
    inet_pton.c:68
              7fffb385fa53 gaih_inet.constprop.7+0xf43 (/usr/lib64/libc-2.26.so)
    getaddrinfo.c:537
              7fffb38605b3 getaddrinfo+0x163 (/usr/lib64/libc-2.26.so)
    getaddrinfo.c:2304
                 130782d6f main+0x3df (/usr/bin/ping)
    ping.c:519
              7fffb377369f generic_start_main.isra.0+0x13f (/usr/lib64/libc-2.26.so)
    libc-start.c:308
              7fffb3773897 __libc_start_main+0xb7 (/usr/lib64/libc-2.26.so)
    libc-start.c:102

Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Fixes: 6754075915 ("perf unwind: Use addr_location::addr instead of ip for entries")
Link: http://lkml.kernel.org/r/20180703120555.32971-1-sandipan@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-07-24 14:53:11 -03:00
Arnaldo Carvalho de Melo
404eb5a436 perf thread: Make thread__find_map() search all maps
We still have the split internally, but users don't see it anymore,
simplifying the growing number of cases where we end up searching
in the MAP__VARIABLE maps.

This further paves the way for ditching the split.

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: https://lkml.kernel.org/n/tip-86mfxrztf310konutxvhr5ua@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-26 13:47:17 -03:00
Arnaldo Carvalho de Melo
71a84b5aed perf thread: Make thread__find_map() return the map
It was returning the searched map just on the addr_location passed, with
the function itself returning void.

Make it return the map so that we can make the code more compact.

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: https://lkml.kernel.org/n/tip-tzlrrzdeoof4i6ktyqv1t6ks@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-26 13:47:08 -03:00
Arnaldo Carvalho de Melo
4546263d72 perf thread: Introduce thread__find_symbol()
Out of thread__find_addr_location(..., MAP__FUNCTION, ...), idea here is to
continue removing references to MAP__{FUNCTION,VARIABLE} ahead of
getting both types of symbols in the same rbtree, as various places do
two lookups, looking first at MAP__FUNCTION, then at MAP__VARIABLE.

So thread__find_symbol() will eventually do just that, and 'struct
symbol' will have the symbol type, for code that cares about that.

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: https://lkml.kernel.org/n/tip-n7528en9e08yd3flzmb26tth@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-26 13:47:07 -03:00
Arnaldo Carvalho de Melo
f07a2d32b5 perf thread: Introduce thread__find_map()
Out of thread__find_add_map(..., MAP__FUNCTION, ...), idea here is to
continue removing references to MAP__{FUNCTION,VARIABLE} ahead of
getting both types of symbols in the same rbtree, as various places do
two lookups, looking first at MAP__FUNCTION, then at MAP__VARIABLE.

So thread__find_map() will eventually do just that, and 'struct symbol'
will have the symbol type, for code that cares about that.

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: https://lkml.kernel.org/n/tip-q27xee34l4izpfau49w103s6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-26 13:47:06 -03:00
Martin Vuille
555fc3b1ef perf unwind: Report error from dwfl_attach_state
In verbose level 2, errors returned by libdw are reported in most cases,
but not when calling dwfl_attach_state.

Since elfutils v 0.160 (2014), dwfl_attach_state sets the error code to
report failure cause. On failure, log the reported error.

Signed-off-by: Martin Vuille <jpmv27@aim.com>
Reviewed-by: Kim Phillips <kim.phillips@arm.com>
Link: http://lkml.kernel.org/r/20180318175053.4222-1-jpmv27@aim.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-03-20 13:16:09 -03:00
Martin Vuille
3d20c62466 perf unwind: Unwind with libdw doesn't take symfs into account
Path passed to libdw for unwinding doesn't include symfs path
if specified, so unwinding fails because ELF file is not found.

Similar to unwinding with libunwind, pass symsrc_filename instead
of long_name. If there is no symsrc_filename, fallback to long_name.

Signed-off-by: Martin Vuille <jpmv27@aim.com>
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/r/20180211212420.18388-1-jpmv27@aim.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-03-16 13:55:51 -03:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Milian Wolff
9126cbbace perf unwind: Report module before querying isactivation in dwfl unwind
The PC returned by dwfl_frame_pc() may map into a not-yet-reported
module. We have to report it before we continue unwinding. But when we
query for the isactivation flag in dwfl_frame_pc, libdw will actually do
one more unwinding step internally which can then break and lead to
missed frames or broken stacks.

With libunwind we get e.g.:

~~~~~
  heaptrack_gui  2228 135073.400474:     613969 cycles:
	          108c8e [unknown] (/usr/lib/libQt5Core.so.5.8.0)
	          1093bc [unknown] (/usr/lib/libQt5Core.so.5.8.0)
	          109e7b QLocale::QLocale (/usr/lib/libQt5Core.so.5.8.0)
	          1470ff [unknown] (/usr/lib/libQt5Core.so.5.8.0)
	          147f67 QSystemLocale::query (/usr/lib/libQt5Core.so.5.8.0)
	          109fbf QLocalePrivate::updateSystemPrivate (/usr/lib/libQt5Core.so.5.8.0)
	          10aa27 QLocale::QLocale (/usr/lib/libQt5Core.so.5.8.0)
	          1e02c3 [unknown] (/usr/lib/libQt5Core.so.5.8.0)
	          2113bb [unknown] (/usr/lib/libQt5Core.so.5.8.0)
	          211505 [unknown] (/usr/lib/libQt5Core.so.5.8.0)
	          1b5df0 QFileInfo::exists (/usr/lib/libQt5Core.so.5.8.0)
	           92eb2 [unknown] (/usr/lib/libQt5Core.so.5.8.0)
	           93423 [unknown] (/usr/lib/libQt5Core.so.5.8.0)
	           93d2a QLibraryInfo::location (/usr/lib/libQt5Core.so.5.8.0)
	          2170af [unknown] (/usr/lib/libQt5Core.so.5.8.0)
	          297c53 QCoreApplicationPrivate::init (/usr/lib/libQt5Core.so.5.8.0)
	           f7cde QGuiApplicationPrivate::init (/usr/lib/libQt5Gui.so.5.8.0)
	          1589e8 QApplicationPrivate::init (/usr/lib/libQt5Widgets.so.5.8.0)
	           78622 main (/home/milian/projects/compiled/other/bin/heaptrack_gui)
	           20439 __libc_start_main (/usr/lib/libc-2.25.so)
	           78299 _start (/home/milian/projects/compiled/other/bin/heaptrack_gui)

  heaptrack_gui  2228 135073.401156:     569521 cycles:
	          131633 QString::endsWith (/usr/lib/libQt5Core.so.5.8.0)
	          1a0701 QDir::cleanPath (/usr/lib/libQt5Core.so.5.8.0)
	          21b82d [unknown] (/usr/lib/libQt5Core.so.5.8.0)
	          1b3727 QFileInfo::canonicalFilePath (/usr/lib/libQt5Core.so.5.8.0)
	          2780c7 QFactoryLoader::update (/usr/lib/libQt5Core.so.5.8.0)
	          279525 QFactoryLoader::QFactoryLoader (/usr/lib/libQt5Core.so.5.8.0)
	           e5bd0 QPlatformIntegrationFactory::create (/usr/lib/libQt5Gui.so.5.8.0)
	           f5a1c QGuiApplicationPrivate::createPlatformIntegration (/usr/lib/libQt5Gui.so.5.8.0)
	           f650c QGuiApplicationPrivate::createEventDispatcher (/usr/lib/libQt5Gui.so.5.8.0)
	          298524 QCoreApplicationPrivate::init (/usr/lib/libQt5Core.so.5.8.0)
	           f7cde QGuiApplicationPrivate::init (/usr/lib/libQt5Gui.so.5.8.0)
	          1589e8 QApplicationPrivate::init (/usr/lib/libQt5Widgets.so.5.8.0)
	           78622 main (/home/milian/projects/compiled/other/bin/heaptrack_gui)
	           20439 __libc_start_main (/usr/lib/libc-2.25.so)
	           78299 _start (/home/milian/projects/compiled/other/bin/heaptrack_gui)
~~~~~

Note the two frames 1589e8 and 78622 in the first sample. These are
missing when unwinding with libdw. The second sample's breakage is
more obvious:

~~~~~
  heaptrack_gui  2228 135073.400474:     613969 cycles:
	          108c8e [unknown] (/usr/lib/libQt5Core.so.5.8.0)
	          1093bc [unknown] (/usr/lib/libQt5Core.so.5.8.0)
	          109e7b QLocale::QLocale (/usr/lib/libQt5Core.so.5.8.0)
	          1470ff [unknown] (/usr/lib/libQt5Core.so.5.8.0)
	          147f67 QSystemLocale::query (/usr/lib/libQt5Core.so.5.8.0)
	          109fbf QLocalePrivate::updateSystemPrivate (/usr/lib/libQt5Core.so.5.8.0)
	          10aa27 QLocale::QLocale (/usr/lib/libQt5Core.so.5.8.0)
	          1e02c3 [unknown] (/usr/lib/libQt5Core.so.5.8.0)
	          2113bb [unknown] (/usr/lib/libQt5Core.so.5.8.0)
	          211505 [unknown] (/usr/lib/libQt5Core.so.5.8.0)
	          1b5df0 QFileInfo::exists (/usr/lib/libQt5Core.so.5.8.0)
	           92eb2 [unknown] (/usr/lib/libQt5Core.so.5.8.0)
	           93423 [unknown] (/usr/lib/libQt5Core.so.5.8.0)
	           93d2a QLibraryInfo::location (/usr/lib/libQt5Core.so.5.8.0)
	          2170af [unknown] (/usr/lib/libQt5Core.so.5.8.0)
	          297c53 QCoreApplicationPrivate::init (/usr/lib/libQt5Core.so.5.8.0)
	           f7cde QGuiApplicationPrivate::init (/usr/lib/libQt5Gui.so.5.8.0)
	           20439 __libc_start_main (/usr/lib/libc-2.25.so)
	           78299 _start (/home/milian/projects/compiled/other/bin/heaptrack_gui)

heaptrack_gui  2228 135073.401156:     569521 cycles:
	          131633 QString::endsWith (/usr/lib/libQt5Core.so.5.8.0)
	          1a0701 QDir::cleanPath (/usr/lib/libQt5Core.so.5.8.0)
	          21b82d [unknown] (/usr/lib/libQt5Core.so.5.8.0)
	          1b3727 QFileInfo::canonicalFilePath (/usr/lib/libQt5Core.so.5.8.0)
	          2780c7 QFactoryLoader::update (/usr/lib/libQt5Core.so.5.8.0)
	          279525 QFactoryLoader::QFactoryLoader (/usr/lib/libQt5Core.so.5.8.0)
	           e5bd0 QPlatformIntegrationFactory::create (/usr/lib/libQt5Gui.so.5.8.0)
	          723dbf [unknown] ([unknown])
~~~~~

This patch fixes this issue and the libdw unwinder mimicks the libunwind
behavior more closely.

Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Acked-by: Jan Kratochvil <jan.kratochvil@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20170602143753.16907-2-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-06-16 14:37:30 -03:00
Milian Wolff
2538b9e245 perf report: Ensure the perf DSO mapping matches what libdw sees
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>
2017-06-05 14:18:05 -03:00
Milian Wolff
5ea0416f51 perf report: Include partial stacks unwound with libdw
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>
2017-06-05 14:18:03 -03:00
Milian Wolff
1982ad48fc perf report: Fix off-by-one for non-activation frames
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>
2017-05-24 08:41:48 +02:00
Arnaldo Carvalho de Melo
9a3993d408 perf tools: Move path related functions to util/path.h
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>
2017-04-19 13:01:53 -03:00
Milian Wolff
6754075915 perf unwind: Use addr_location::addr instead of ip for entries
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>
2016-08-16 15:23:29 -03:00
Jiri Olsa
0ba98149f8 perf libdw: Check for mmaps also in MAP__VARIABLE tree
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>
2016-01-08 14:16:57 -03:00
Jiri Olsa
8bd508b001 perf callchain: Add order support for libdw DWARF unwinder
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>
2015-11-23 18:31:13 -03:00
Arnaldo Carvalho de Melo
dd8c17a5fe perf callchains: Use thread->mg->machine
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>
2014-10-29 10:32:46 -02:00
Arnaldo Carvalho de Melo
bb871a9c8d perf tools: A thread's machine can be found via thread->mg->machine
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>
2014-10-29 10:32:46 -02:00
Jiri Olsa
84f5d36f48 perf tools: Move pr_* debug macros into debug object
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>
2014-07-17 12:58:39 -03:00
Borislav Petkov
d944c4eebc tools: Consolidate types.h
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>
2014-05-01 21:22:39 +02:00
Jiri Olsa
5ea8415407 perf tools: Add libdw DWARF post unwind support
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>
2014-02-24 09:29:36 -03:00