<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/tools/lib/bpf, branch v5.1-rc2</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge tag 'perf-core-for-mingo-5.1-20190321' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent</title>
<updated>2019-03-22T21:51:21+00:00</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2019-03-22T21:51:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d8b5297f6d985d785b2d2869102933e81ca51c80'/>
<id>d8b5297f6d985d785b2d2869102933e81ca51c80</id>
<content type='text'>
Pull perf/core improvements and fixes from Arnaldo:

BPF:

  Song Liu:

  - Add support for annotating BPF programs, using the PERF_RECORD_BPF_EVENT
    and PERF_RECORD_KSYMBOL recently added to the kernel and plugging
    binutils's libopcodes disassembly of BPF programs with the existing
    annotation interfaces in 'perf annotate', 'perf report' and 'perf top'
    various output formats (--stdio, --stdio2, --tui).

perf list:

  Andi Kleen:

  - Filter metrics when using substring search.

perf record:

  Andi Kleen:

  - Allow to limit number of reported perf.data files

  - Clarify help for --switch-output.

perf report:

  Andi Kleen

  - Indicate JITed code better.

  - Show all sort keys in help output.

perf script:

  Andi Kleen:

  - Support relative time.

perf stat:

  Andi Kleen:

  - Improve scaling.

General:

  Changbin Du:

  - Fix some mostly error path memory and reference count leaks found
    using gcc's ASan and UBSan.

Vendor events:

  Mamatha Inamdar:

  - Remove P8 HW events which are not supported.

Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull perf/core improvements and fixes from Arnaldo:

BPF:

  Song Liu:

  - Add support for annotating BPF programs, using the PERF_RECORD_BPF_EVENT
    and PERF_RECORD_KSYMBOL recently added to the kernel and plugging
    binutils's libopcodes disassembly of BPF programs with the existing
    annotation interfaces in 'perf annotate', 'perf report' and 'perf top'
    various output formats (--stdio, --stdio2, --tui).

perf list:

  Andi Kleen:

  - Filter metrics when using substring search.

perf record:

  Andi Kleen:

  - Allow to limit number of reported perf.data files

  - Clarify help for --switch-output.

perf report:

  Andi Kleen

  - Indicate JITed code better.

  - Show all sort keys in help output.

perf script:

  Andi Kleen:

  - Support relative time.

perf stat:

  Andi Kleen:

  - Improve scaling.

General:

  Changbin Du:

  - Fix some mostly error path memory and reference count leaks found
    using gcc's ASan and UBSan.

Vendor events:

  Mamatha Inamdar:

  - Remove P8 HW events which are not supported.

Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'perf-core-for-mingo-5.1-20190311' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent</title>
<updated>2019-03-22T21:50:41+00:00</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2019-03-22T21:50:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4a98be82937325fd769cdfebf4c43dd26aa769d6'/>
<id>4a98be82937325fd769cdfebf4c43dd26aa769d6</id>
<content type='text'>
Pull perf/core improvements and fixes from Arnaldo:

kernel:

  Stephane Eranian :

  - Restore mmap record type correctly when handling PERF_RECORD_MMAP2
    events, as the same template is used for all the threads interested
    in mmap events, some may want just PERF_RECORD_MMAP, while some
    may want the extra info in MMAP2 records.

perf probe:

  Adrian Hunter:

  - Fix getting the kernel map, because since changes related to x86 PTI
    entry trampolines handling, there are more than one kernel map.

perf script:

  Andi Kleen:

  - Support insn output for normal samples, i.e.:

    perf script -F ip,sym,insn --xed

    Will fetch the sample IP from the thread address space and feed it
    to Intel's XED disassembler, producing lines such as:

      ffffffffa4068804 native_write_msr            wrmsr
      ffffffffa415b95e __hrtimer_next_event_base   movq  0x18(%rax), %rdx

    That match 'perf annotate's output.

  - Make the --cpu filter apply to  PERF_RECORD_COMM/FORK/... events, in
    addition to PERF_RECORD_SAMPLE.

perf report:

  - Add a new --samples option to save a small random number of samples
    per hist entry, using a reservoir technique to select a representative
    number of samples.

    Then allow browsing the samples using 'perf script' as part of the hist
    entry context menu. This automatically adds the right filters, so only
    the thread or CPU of the sample is displayed. Then we use less' search
    functionality to directly jump to the time stamp of the selected sample.

    It uses different menus for assembler and source display.  Assembler
    needs xed installed and source needs debuginfo.

  - Fix the UI browser scripts pop up menu when there are many scripts
    available.

perf report:

  Andi Kleen:

  - Add 'time' sort option. E.g.:

    % perf report --sort time,overhead,symbol --time-quantum 1ms --stdio
    ...
         0.67%  277061.87300  [.] _dl_start
         0.50%  277061.87300  [.] f1
         0.50%  277061.87300  [.] f2
         0.33%  277061.87300  [.] main
         0.29%  277061.87300  [.] _dl_lookup_symbol_x
         0.29%  277061.87300  [.] dl_main
         0.29%  277061.87300  [.] do_lookup_x
         0.17%  277061.87300  [.] _dl_debug_initialize
         0.17%  277061.87300  [.] _dl_init_paths
         0.08%  277061.87300  [.] check_match
         0.04%  277061.87300  [.] _dl_count_modids
         1.33%  277061.87400  [.] f1
         1.33%  277061.87400  [.] f2
         1.33%  277061.87400  [.] main
         1.17%  277061.87500  [.] main
         1.08%  277061.87500  [.] f1
         1.08%  277061.87500  [.] f2
         1.00%  277061.87600  [.] main
         0.83%  277061.87600  [.] f1
         0.83%  277061.87600  [.] f2
         1.00%  277061.87700  [.] main

tools headers:

  Arnaldo Carvalho de Melo:

  - Update x86's syscall_64.tbl, no change in tools/perf behaviour.

  -  Sync copies asm-generic/unistd.h and linux/in with the kernel sources.

perf data:

  Jiri Olsa:

  - Prep work to support having perf.data stored as a directory, with one
    file per CPU, that ultimately will allow having one ring buffer reading
    thread per CPU.

Vendor events:

  Martin Liška:

  - perf PMU events for AMD Family 17h.

perf script python:

  Tony Jones:

  - Add python3 support for the remaining Intel PT related scripts, with
    these we should have a clean build of perf with python3 while still
    supporting the build with python2.

libbpf:

  Arnaldo Carvalho de Melo:

  - Fix the build on uCLibc, adding the missing stdarg.h since we use
    va_list in one typedef.

Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull perf/core improvements and fixes from Arnaldo:

kernel:

  Stephane Eranian :

  - Restore mmap record type correctly when handling PERF_RECORD_MMAP2
    events, as the same template is used for all the threads interested
    in mmap events, some may want just PERF_RECORD_MMAP, while some
    may want the extra info in MMAP2 records.

perf probe:

  Adrian Hunter:

  - Fix getting the kernel map, because since changes related to x86 PTI
    entry trampolines handling, there are more than one kernel map.

perf script:

  Andi Kleen:

  - Support insn output for normal samples, i.e.:

    perf script -F ip,sym,insn --xed

    Will fetch the sample IP from the thread address space and feed it
    to Intel's XED disassembler, producing lines such as:

      ffffffffa4068804 native_write_msr            wrmsr
      ffffffffa415b95e __hrtimer_next_event_base   movq  0x18(%rax), %rdx

    That match 'perf annotate's output.

  - Make the --cpu filter apply to  PERF_RECORD_COMM/FORK/... events, in
    addition to PERF_RECORD_SAMPLE.

perf report:

  - Add a new --samples option to save a small random number of samples
    per hist entry, using a reservoir technique to select a representative
    number of samples.

    Then allow browsing the samples using 'perf script' as part of the hist
    entry context menu. This automatically adds the right filters, so only
    the thread or CPU of the sample is displayed. Then we use less' search
    functionality to directly jump to the time stamp of the selected sample.

    It uses different menus for assembler and source display.  Assembler
    needs xed installed and source needs debuginfo.

  - Fix the UI browser scripts pop up menu when there are many scripts
    available.

perf report:

  Andi Kleen:

  - Add 'time' sort option. E.g.:

    % perf report --sort time,overhead,symbol --time-quantum 1ms --stdio
    ...
         0.67%  277061.87300  [.] _dl_start
         0.50%  277061.87300  [.] f1
         0.50%  277061.87300  [.] f2
         0.33%  277061.87300  [.] main
         0.29%  277061.87300  [.] _dl_lookup_symbol_x
         0.29%  277061.87300  [.] dl_main
         0.29%  277061.87300  [.] do_lookup_x
         0.17%  277061.87300  [.] _dl_debug_initialize
         0.17%  277061.87300  [.] _dl_init_paths
         0.08%  277061.87300  [.] check_match
         0.04%  277061.87300  [.] _dl_count_modids
         1.33%  277061.87400  [.] f1
         1.33%  277061.87400  [.] f2
         1.33%  277061.87400  [.] main
         1.17%  277061.87500  [.] main
         1.08%  277061.87500  [.] f1
         1.08%  277061.87500  [.] f2
         1.00%  277061.87600  [.] main
         0.83%  277061.87600  [.] f1
         0.83%  277061.87600  [.] f2
         1.00%  277061.87700  [.] main

tools headers:

  Arnaldo Carvalho de Melo:

  - Update x86's syscall_64.tbl, no change in tools/perf behaviour.

  -  Sync copies asm-generic/unistd.h and linux/in with the kernel sources.

perf data:

  Jiri Olsa:

  - Prep work to support having perf.data stored as a directory, with one
    file per CPU, that ultimately will allow having one ring buffer reading
    thread per CPU.

Vendor events:

  Martin Liška:

  - perf PMU events for AMD Family 17h.

perf script python:

  Tony Jones:

  - Add python3 support for the remaining Intel PT related scripts, with
    these we should have a clean build of perf with python3 while still
    supporting the build with python2.

libbpf:

  Arnaldo Carvalho de Melo:

  - Fix the build on uCLibc, adding the missing stdarg.h since we use
    va_list in one typedef.

Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools lib bpf: Introduce bpf_program__get_prog_info_linear()</title>
<updated>2019-03-19T19:52:06+00:00</updated>
<author>
<name>Song Liu</name>
<email>songliubraving@fb.com</email>
</author>
<published>2019-03-12T05:30:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=34be16466d4dc06f3d604dafbcdb3327b72e78da'/>
<id>34be16466d4dc06f3d604dafbcdb3327b72e78da</id>
<content type='text'>
Currently, bpf_prog_info includes 9 arrays. The user has the option to
fetch any combination of these arrays. However, this requires a lot of
handling.

This work becomes more tricky when we need to store bpf_prog_info to a
file, because these arrays are allocated independently.

This patch introduces 'struct bpf_prog_info_linear', which stores arrays
of bpf_prog_info in continuous memory.

Helper functions are introduced to unify the work to get different sets
of bpf_prog_info.  Specifically, bpf_program__get_prog_info_linear()
allows the user to select which arrays to fetch, and handles details for
the user.

Please see the comments right before 'enum bpf_prog_info_array' for more
details and examples.

Signed-off-by: Song Liu &lt;songliubraving@fb.com&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Acked-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Link: https://lkml.kernel.org/r/ce92c091-e80d-a0c1-4aa0-987706c42b20@iogearbox.net
Tested-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Cc: Alexei Starovoitov &lt;ast@kernel.org&gt;
Cc: kernel-team@fb.com
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Stanislav Fomichev &lt;sdf@google.com&gt;
Link: http://lkml.kernel.org/r/20190312053051.2690567-3-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Currently, bpf_prog_info includes 9 arrays. The user has the option to
fetch any combination of these arrays. However, this requires a lot of
handling.

This work becomes more tricky when we need to store bpf_prog_info to a
file, because these arrays are allocated independently.

This patch introduces 'struct bpf_prog_info_linear', which stores arrays
of bpf_prog_info in continuous memory.

Helper functions are introduced to unify the work to get different sets
of bpf_prog_info.  Specifically, bpf_program__get_prog_info_linear()
allows the user to select which arrays to fetch, and handles details for
the user.

Please see the comments right before 'enum bpf_prog_info_array' for more
details and examples.

Signed-off-by: Song Liu &lt;songliubraving@fb.com&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Acked-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Link: https://lkml.kernel.org/r/ce92c091-e80d-a0c1-4aa0-987706c42b20@iogearbox.net
Tested-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Cc: Alexei Starovoitov &lt;ast@kernel.org&gt;
Cc: kernel-team@fb.com
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Stanislav Fomichev &lt;sdf@google.com&gt;
Link: http://lkml.kernel.org/r/20190312053051.2690567-3-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf tools: Fix errors under optimization level '-Og'</title>
<updated>2019-03-19T19:52:04+00:00</updated>
<author>
<name>Changbin Du</name>
<email>changbin.du@gmail.com</email>
</author>
<published>2019-03-16T08:05:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=11c1ea6f1a9bc97bf857fd12f72eacb6c69794e2'/>
<id>11c1ea6f1a9bc97bf857fd12f72eacb6c69794e2</id>
<content type='text'>
Optimization level '-Og' offers a reasonable level of optimization while
maintaining fast compilation and a good debugging experience. This patch
tries to make it work.

  $ make DEBUG=1 EXTRA_CFLAGS='-Og'
  bench/epoll-ctl.c: In function ‘do_threads’:
  bench/epoll-ctl.c:274:9: error: ‘ret’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
    return ret;
           ^~~
  ...

Signed-off-by: Changbin Du &lt;changbin.du@gmail.com&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alexei Starovoitov &lt;ast@kernel.org&gt;
Cc: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Link: http://lkml.kernel.org/r/20190316080556.3075-4-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Optimization level '-Og' offers a reasonable level of optimization while
maintaining fast compilation and a good debugging experience. This patch
tries to make it work.

  $ make DEBUG=1 EXTRA_CFLAGS='-Og'
  bench/epoll-ctl.c: In function ‘do_threads’:
  bench/epoll-ctl.c:274:9: error: ‘ret’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
    return ret;
           ^~~
  ...

Signed-off-by: Changbin Du &lt;changbin.du@gmail.com&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alexei Starovoitov &lt;ast@kernel.org&gt;
Cc: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Link: http://lkml.kernel.org/r/20190316080556.3075-4-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools lib bpf: Fix the build by adding a missing stdarg.h include</title>
<updated>2019-03-11T20:14:31+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2019-03-11T20:07:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=dfcbc2f2994b8a3af3605a26dc29c07ad7378bf4'/>
<id>dfcbc2f2994b8a3af3605a26dc29c07ad7378bf4</id>
<content type='text'>
The libbpf_print_fn_t typedef uses va_list without including the header
where that type is defined, stdarg.h, breaking in places where we're
unlucky for that type not to be already defined by some previously
included header.

Noticed while building on fedora 24 cross building tools/perf to the ARC
architecture using the uClibc C library:

  28 fedora:24-x-ARC-uClibc   : FAIL arc-linux-gcc (ARCompact ISA Linux uClibc toolchain 2017.09-rc2) 7.1.1 20170710

    CC       /tmp/build/perf/tests/llvm.o
  In file included from tests/llvm.c:3:0:
  /git/linux/tools/lib/bpf/libbpf.h:57:20: error: unknown type name 'va_list'
        const char *, va_list ap);
                      ^~~~~~~
  /git/linux/tools/lib/bpf/libbpf.h:59:34: error: unknown type name 'libbpf_print_fn_t'
   LIBBPF_API void libbpf_set_print(libbpf_print_fn_t fn);
                                    ^~~~~~~~~~~~~~~~~
  mv: cannot stat '/tmp/build/perf/tests/.llvm.o.tmp': No such file or directory

Cc: Alexei Starovoitov &lt;ast@kernel.org&gt;
Cc: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Cc: Jakub Kicinski &lt;jakub.kicinski@netronome.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Quentin Monnet &lt;quentin.monnet@netronome.com&gt;
Cc: Stanislav Fomichev &lt;sdf@google.com&gt;
Cc: Yonghong Song &lt;yhs@fb.com&gt;
Fixes: a8a1f7d09cfc ("libbpf: fix libbpf_print")
Link: https://lkml.kernel.org/n/tip-5270n2quu2gqz22o7itfdx00@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The libbpf_print_fn_t typedef uses va_list without including the header
where that type is defined, stdarg.h, breaking in places where we're
unlucky for that type not to be already defined by some previously
included header.

Noticed while building on fedora 24 cross building tools/perf to the ARC
architecture using the uClibc C library:

  28 fedora:24-x-ARC-uClibc   : FAIL arc-linux-gcc (ARCompact ISA Linux uClibc toolchain 2017.09-rc2) 7.1.1 20170710

    CC       /tmp/build/perf/tests/llvm.o
  In file included from tests/llvm.c:3:0:
  /git/linux/tools/lib/bpf/libbpf.h:57:20: error: unknown type name 'va_list'
        const char *, va_list ap);
                      ^~~~~~~
  /git/linux/tools/lib/bpf/libbpf.h:59:34: error: unknown type name 'libbpf_print_fn_t'
   LIBBPF_API void libbpf_set_print(libbpf_print_fn_t fn);
                                    ^~~~~~~~~~~~~~~~~
  mv: cannot stat '/tmp/build/perf/tests/.llvm.o.tmp': No such file or directory

Cc: Alexei Starovoitov &lt;ast@kernel.org&gt;
Cc: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Cc: Jakub Kicinski &lt;jakub.kicinski@netronome.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Quentin Monnet &lt;quentin.monnet@netronome.com&gt;
Cc: Stanislav Fomichev &lt;sdf@google.com&gt;
Cc: Yonghong Song &lt;yhs@fb.com&gt;
Fixes: a8a1f7d09cfc ("libbpf: fix libbpf_print")
Link: https://lkml.kernel.org/n/tip-5270n2quu2gqz22o7itfdx00@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bpf, libbpf: fixing leak when kernel does not support btf</title>
<updated>2019-03-08T20:16:36+00:00</updated>
<author>
<name>Nikita V. Shirokov</name>
<email>tehnerd@tehnerd.com</email>
</author>
<published>2019-03-08T05:18:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=243b4cdab981d7004bee56c38e18a29da32ef104'/>
<id>243b4cdab981d7004bee56c38e18a29da32ef104</id>
<content type='text'>
We could end up in situation when we have object file w/ all btf
info, but kernel does not support btf yet. In this situation
currently libbpf just set obj-&gt;btf to NULL w/o freeing it first.
This patch is fixing it by making sure to run btf__free first.

Fixes: d29d87f7e612 ("btf: separate btf creation and loading")
Signed-off-by: Nikita V. Shirokov &lt;tehnerd@tehnerd.com&gt;
Acked-by: Yonghong Song &lt;yhs@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We could end up in situation when we have object file w/ all btf
info, but kernel does not support btf yet. In this situation
currently libbpf just set obj-&gt;btf to NULL w/o freeing it first.
This patch is fixing it by making sure to run btf__free first.

Fixes: d29d87f7e612 ("btf: separate btf creation and loading")
Signed-off-by: Nikita V. Shirokov &lt;tehnerd@tehnerd.com&gt;
Acked-by: Yonghong Song &lt;yhs@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>libbpf: force fixdep compilation at the start of the build</title>
<updated>2019-03-07T09:44:41+00:00</updated>
<author>
<name>Stanislav Fomichev</name>
<email>sdf@google.com</email>
</author>
<published>2019-03-06T19:59:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=8e2688876c7f7073d925e1f150e86b8ed3338f52'/>
<id>8e2688876c7f7073d925e1f150e86b8ed3338f52</id>
<content type='text'>
libbpf targets don't explicitly depend on fixdep target, so when
we do 'make -j$(nproc)', there is a high probability, that some
objects will be built before fixdep binary is available.

Fix this by running sub-make; this makes sure that fixdep dependency
is properly accounted for.

For the same issue in perf, see commit abb26210a395 ("perf tools: Force
fixdep compilation at the start of the build").

Before:

$ rm -rf /tmp/bld; mkdir /tmp/bld; make -j$(nproc) O=/tmp/bld -C tools/lib/bpf/

Auto-detecting system features:
...                        libelf: [ on  ]
...                           bpf: [ on  ]

  HOSTCC   /tmp/bld/fixdep.o
  CC       /tmp/bld/libbpf.o
  CC       /tmp/bld/bpf.o
  CC       /tmp/bld/btf.o
  CC       /tmp/bld/nlattr.o
  CC       /tmp/bld/libbpf_errno.o
  CC       /tmp/bld/str_error.o
  CC       /tmp/bld/netlink.o
  CC       /tmp/bld/bpf_prog_linfo.o
  CC       /tmp/bld/libbpf_probes.o
  CC       /tmp/bld/xsk.o
  HOSTLD   /tmp/bld/fixdep-in.o
  LINK     /tmp/bld/fixdep
  LD       /tmp/bld/libbpf-in.o
  LINK     /tmp/bld/libbpf.a
  LINK     /tmp/bld/libbpf.so
  LINK     /tmp/bld/test_libbpf

$ head /tmp/bld/.libbpf.o.cmd
 # cannot find fixdep (/usr/local/google/home/sdf/src/linux/xxx//fixdep)
 # using basic dep data

/tmp/bld/libbpf.o: libbpf.c /usr/include/stdc-predef.h \
 /usr/include/stdlib.h /usr/include/features.h \
 /usr/include/x86_64-linux-gnu/sys/cdefs.h \
 /usr/include/x86_64-linux-gnu/bits/wordsize.h \
 /usr/include/x86_64-linux-gnu/gnu/stubs.h \
 /usr/include/x86_64-linux-gnu/gnu/stubs-64.h \
 /usr/lib/gcc/x86_64-linux-gnu/7/include/stddef.h \

After:

$ rm -rf /tmp/bld; mkdir /tmp/bld; make -j$(nproc) O=/tmp/bld -C tools/lib/bpf/

Auto-detecting system features:
...                        libelf: [ on  ]
...                           bpf: [ on  ]

  HOSTCC   /tmp/bld/fixdep.o
  HOSTLD   /tmp/bld/fixdep-in.o
  LINK     /tmp/bld/fixdep
  CC       /tmp/bld/libbpf.o
  CC       /tmp/bld/bpf.o
  CC       /tmp/bld/nlattr.o
  CC       /tmp/bld/btf.o
  CC       /tmp/bld/libbpf_errno.o
  CC       /tmp/bld/str_error.o
  CC       /tmp/bld/netlink.o
  CC       /tmp/bld/bpf_prog_linfo.o
  CC       /tmp/bld/libbpf_probes.o
  CC       /tmp/bld/xsk.o
  LD       /tmp/bld/libbpf-in.o
  LINK     /tmp/bld/libbpf.a
  LINK     /tmp/bld/libbpf.so
  LINK     /tmp/bld/test_libbpf

$ head /tmp/bld/.libbpf.o.cmd
cmd_/tmp/bld/libbpf.o := gcc -Wp,-MD,/tmp/bld/.libbpf.o.d -Wp,-MT,/tmp/bld/libbpf.o -g -Wall -DHAVE_LIBELF_MMAP_SUPPORT -DCOMPAT_NEED_REALLOCARRAY -Wbad-function-cast -Wdeclaration-after-statement -Wformat-security -Wformat-y2k -Winit-self -Wmissing-declarations -Wmissing-prototypes -Wnested-externs -Wno-system-headers -Wold-style-definition -Wpacked -Wredundant-decls -Wshadow -Wstrict-prototypes -Wswitch-default -Wswitch-enum -Wundef -Wwrite-strings -Wformat -Wstrict-aliasing=3 -Werror -Wall -fPIC -I. -I/usr/local/google/home/sdf/src/linux/tools/include -I/usr/local/google/home/sdf/src/linux/tools/arch/x86/include/uapi -I/usr/local/google/home/sdf/src/linux/tools/include/uapi -fvisibility=hidden -D"BUILD_STR(s)=$(pound)s" -c -o /tmp/bld/libbpf.o libbpf.c

source_/tmp/bld/libbpf.o := libbpf.c

deps_/tmp/bld/libbpf.o := \
  /usr/include/stdc-predef.h \
  /usr/include/stdlib.h \
  /usr/include/features.h \
  /usr/include/x86_64-linux-gnu/sys/cdefs.h \
  /usr/include/x86_64-linux-gnu/bits/wordsize.h \

Fixes: 7c422f557266 ("tools build: Build fixdep helper from perf and basic libs")
Reported-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: Stanislav Fomichev &lt;sdf@google.com&gt;
Acked-by: Yonghong Song &lt;yhs@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
libbpf targets don't explicitly depend on fixdep target, so when
we do 'make -j$(nproc)', there is a high probability, that some
objects will be built before fixdep binary is available.

Fix this by running sub-make; this makes sure that fixdep dependency
is properly accounted for.

For the same issue in perf, see commit abb26210a395 ("perf tools: Force
fixdep compilation at the start of the build").

Before:

$ rm -rf /tmp/bld; mkdir /tmp/bld; make -j$(nproc) O=/tmp/bld -C tools/lib/bpf/

Auto-detecting system features:
...                        libelf: [ on  ]
...                           bpf: [ on  ]

  HOSTCC   /tmp/bld/fixdep.o
  CC       /tmp/bld/libbpf.o
  CC       /tmp/bld/bpf.o
  CC       /tmp/bld/btf.o
  CC       /tmp/bld/nlattr.o
  CC       /tmp/bld/libbpf_errno.o
  CC       /tmp/bld/str_error.o
  CC       /tmp/bld/netlink.o
  CC       /tmp/bld/bpf_prog_linfo.o
  CC       /tmp/bld/libbpf_probes.o
  CC       /tmp/bld/xsk.o
  HOSTLD   /tmp/bld/fixdep-in.o
  LINK     /tmp/bld/fixdep
  LD       /tmp/bld/libbpf-in.o
  LINK     /tmp/bld/libbpf.a
  LINK     /tmp/bld/libbpf.so
  LINK     /tmp/bld/test_libbpf

$ head /tmp/bld/.libbpf.o.cmd
 # cannot find fixdep (/usr/local/google/home/sdf/src/linux/xxx//fixdep)
 # using basic dep data

/tmp/bld/libbpf.o: libbpf.c /usr/include/stdc-predef.h \
 /usr/include/stdlib.h /usr/include/features.h \
 /usr/include/x86_64-linux-gnu/sys/cdefs.h \
 /usr/include/x86_64-linux-gnu/bits/wordsize.h \
 /usr/include/x86_64-linux-gnu/gnu/stubs.h \
 /usr/include/x86_64-linux-gnu/gnu/stubs-64.h \
 /usr/lib/gcc/x86_64-linux-gnu/7/include/stddef.h \

After:

$ rm -rf /tmp/bld; mkdir /tmp/bld; make -j$(nproc) O=/tmp/bld -C tools/lib/bpf/

Auto-detecting system features:
...                        libelf: [ on  ]
...                           bpf: [ on  ]

  HOSTCC   /tmp/bld/fixdep.o
  HOSTLD   /tmp/bld/fixdep-in.o
  LINK     /tmp/bld/fixdep
  CC       /tmp/bld/libbpf.o
  CC       /tmp/bld/bpf.o
  CC       /tmp/bld/nlattr.o
  CC       /tmp/bld/btf.o
  CC       /tmp/bld/libbpf_errno.o
  CC       /tmp/bld/str_error.o
  CC       /tmp/bld/netlink.o
  CC       /tmp/bld/bpf_prog_linfo.o
  CC       /tmp/bld/libbpf_probes.o
  CC       /tmp/bld/xsk.o
  LD       /tmp/bld/libbpf-in.o
  LINK     /tmp/bld/libbpf.a
  LINK     /tmp/bld/libbpf.so
  LINK     /tmp/bld/test_libbpf

$ head /tmp/bld/.libbpf.o.cmd
cmd_/tmp/bld/libbpf.o := gcc -Wp,-MD,/tmp/bld/.libbpf.o.d -Wp,-MT,/tmp/bld/libbpf.o -g -Wall -DHAVE_LIBELF_MMAP_SUPPORT -DCOMPAT_NEED_REALLOCARRAY -Wbad-function-cast -Wdeclaration-after-statement -Wformat-security -Wformat-y2k -Winit-self -Wmissing-declarations -Wmissing-prototypes -Wnested-externs -Wno-system-headers -Wold-style-definition -Wpacked -Wredundant-decls -Wshadow -Wstrict-prototypes -Wswitch-default -Wswitch-enum -Wundef -Wwrite-strings -Wformat -Wstrict-aliasing=3 -Werror -Wall -fPIC -I. -I/usr/local/google/home/sdf/src/linux/tools/include -I/usr/local/google/home/sdf/src/linux/tools/arch/x86/include/uapi -I/usr/local/google/home/sdf/src/linux/tools/include/uapi -fvisibility=hidden -D"BUILD_STR(s)=$(pound)s" -c -o /tmp/bld/libbpf.o libbpf.c

source_/tmp/bld/libbpf.o := libbpf.c

deps_/tmp/bld/libbpf.o := \
  /usr/include/stdc-predef.h \
  /usr/include/stdlib.h \
  /usr/include/features.h \
  /usr/include/x86_64-linux-gnu/sys/cdefs.h \
  /usr/include/x86_64-linux-gnu/bits/wordsize.h \

Fixes: 7c422f557266 ("tools build: Build fixdep helper from perf and basic libs")
Reported-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: Stanislav Fomichev &lt;sdf@google.com&gt;
Acked-by: Yonghong Song &lt;yhs@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>btf: fix bug with resolving STRUCT/UNION into corresponding FWD</title>
<updated>2019-03-01T00:31:48+00:00</updated>
<author>
<name>Andrii Nakryiko</name>
<email>andriin@fb.com</email>
</author>
<published>2019-02-28T23:31:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=91097fbee4c025ac72f91ae41feba3a822cc1316'/>
<id>91097fbee4c025ac72f91ae41feba3a822cc1316</id>
<content type='text'>
When checking available canonical candidates for struct/union algorithm
utilizes btf_dedup_is_equiv to determine if candidate is suitable. This
check is not enough when candidate is corresponding FWD for that
struct/union, because according to equivalence logic they are
equivalent. When it so happens that FWD and STRUCT/UNION end in hashing
to the same bucket, it's possible to create remapping loop from FWD to
STRUCT and STRUCT to same FWD, which will cause btf_dedup() to loop
forever.

This patch fixes the issue by additionally checking that type and
canonical candidate are strictly equal (utilizing btf_equal_struct).

Fixes: d5caef5b5655 ("btf: add BTF types deduplication algorithm")
Reported-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Andrii Nakryiko &lt;andriin@fb.com&gt;
Acked-by: Song Liu &lt;songliubraving@fb.com&gt;
Acked-by: Yonghong Song &lt;yhs@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When checking available canonical candidates for struct/union algorithm
utilizes btf_dedup_is_equiv to determine if candidate is suitable. This
check is not enough when candidate is corresponding FWD for that
struct/union, because according to equivalence logic they are
equivalent. When it so happens that FWD and STRUCT/UNION end in hashing
to the same bucket, it's possible to create remapping loop from FWD to
STRUCT and STRUCT to same FWD, which will cause btf_dedup() to loop
forever.

This patch fixes the issue by additionally checking that type and
canonical candidate are strictly equal (utilizing btf_equal_struct).

Fixes: d5caef5b5655 ("btf: add BTF types deduplication algorithm")
Reported-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Andrii Nakryiko &lt;andriin@fb.com&gt;
Acked-by: Song Liu &lt;songliubraving@fb.com&gt;
Acked-by: Yonghong Song &lt;yhs@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>btf: allow to customize dedup hash table size</title>
<updated>2019-03-01T00:31:47+00:00</updated>
<author>
<name>Andrii Nakryiko</name>
<email>andriin@fb.com</email>
</author>
<published>2019-02-28T23:31:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=51edf5f6e015c48b62e24ab2fbcad8885ca1c74e'/>
<id>51edf5f6e015c48b62e24ab2fbcad8885ca1c74e</id>
<content type='text'>
Default size of dedup table (16k) is good enough for most binaries, even
typical vmlinux images. But there are cases of binaries with huge amount
of BTF types (e.g., allyesconfig variants of kernel), which benefit from
having bigger dedup table size to lower amount of unnecessary hash
collisions. Tools like pahole, thus, can tune this parameter to reach
optimal performance.

This change also serves double purpose of allowing tests to force hash
collisions to test some corner cases, used in follow up patch.

Signed-off-by: Andrii Nakryiko &lt;andriin@fb.com&gt;
Acked-by: Yonghong Song &lt;yhs@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Default size of dedup table (16k) is good enough for most binaries, even
typical vmlinux images. But there are cases of binaries with huge amount
of BTF types (e.g., allyesconfig variants of kernel), which benefit from
having bigger dedup table size to lower amount of unnecessary hash
collisions. Tools like pahole, thus, can tune this parameter to reach
optimal performance.

This change also serves double purpose of allowing tests to force hash
collisions to test some corner cases, used in follow up patch.

Signed-off-by: Andrii Nakryiko &lt;andriin@fb.com&gt;
Acked-by: Yonghong Song &lt;yhs@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>libbpf: fix formatting for btf_ext__get_raw_data</title>
<updated>2019-03-01T00:31:47+00:00</updated>
<author>
<name>Andrii Nakryiko</name>
<email>andriin@fb.com</email>
</author>
<published>2019-02-28T23:31:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=1baabdc1089eb807cdcabebad50b36c8b9895a48'/>
<id>1baabdc1089eb807cdcabebad50b36c8b9895a48</id>
<content type='text'>
Fix invalid formatting of pointer arg.

Signed-off-by: Andrii Nakryiko &lt;andriin@fb.com&gt;
Acked-by: Song Liu &lt;songliubraving@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Fix invalid formatting of pointer arg.

Signed-off-by: Andrii Nakryiko &lt;andriin@fb.com&gt;
Acked-by: Song Liu &lt;songliubraving@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</pre>
</div>
</content>
</entry>
</feed>
