<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/tools/build/feature, branch linux-5.0.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>perf cs-etm: Add missing case value</title>
<updated>2019-05-04T07:21:22+00:00</updated>
<author>
<name>Solomon Tan</name>
<email>solomonbobstoner@gmail.com</email>
</author>
<published>2019-03-22T05:22:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=441d23c8764449c3219e7d97eb3b5a98be7c534f'/>
<id>441d23c8764449c3219e7d97eb3b5a98be7c534f</id>
<content type='text'>
[ Upstream commit c8fa7a807f3c5f946bd92076fbaf7826edb650dc ]

The following error was thrown when compiling `tools/perf` using OpenCSD
v0.11.1. This patch fixes said error.

    CC       util/intel-pt-decoder/intel-pt-log.o
    CC       util/cs-etm-decoder/cs-etm-decoder.o
  util/cs-etm-decoder/cs-etm-decoder.c: In function
  ‘cs_etm_decoder__buffer_range’:
  util/cs-etm-decoder/cs-etm-decoder.c:370:2: error: enumeration value
  ‘OCSD_INSTR_WFI_WFE’ not handled in switch [-Werror=switch-enum]
    switch (elem-&gt;last_i_type) {
    ^~~~~~
    CC       util/intel-pt-decoder/intel-pt-decoder.o
  cc1: all warnings being treated as errors

Because `OCSD_INSTR_WFI_WFE` case was added only in v0.11.0, the minimum
required OpenCSD library version for this patch is no longer v0.10.0.

Signed-off-by: Solomon Tan &lt;solomonbobstoner@gmail.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Mathieu Poirier &lt;mathieu.poirier@linaro.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Robert Walker &lt;robert.walker@arm.com&gt;
Cc: Suzuki K Poulouse &lt;suzuki.poulose@arm.com&gt;
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20190322052255.GA4809@w-OptiPlex-7050
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin (Microsoft) &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit c8fa7a807f3c5f946bd92076fbaf7826edb650dc ]

The following error was thrown when compiling `tools/perf` using OpenCSD
v0.11.1. This patch fixes said error.

    CC       util/intel-pt-decoder/intel-pt-log.o
    CC       util/cs-etm-decoder/cs-etm-decoder.o
  util/cs-etm-decoder/cs-etm-decoder.c: In function
  ‘cs_etm_decoder__buffer_range’:
  util/cs-etm-decoder/cs-etm-decoder.c:370:2: error: enumeration value
  ‘OCSD_INSTR_WFI_WFE’ not handled in switch [-Werror=switch-enum]
    switch (elem-&gt;last_i_type) {
    ^~~~~~
    CC       util/intel-pt-decoder/intel-pt-decoder.o
  cc1: all warnings being treated as errors

Because `OCSD_INSTR_WFI_WFE` case was added only in v0.11.0, the minimum
required OpenCSD library version for this patch is no longer v0.10.0.

Signed-off-by: Solomon Tan &lt;solomonbobstoner@gmail.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Mathieu Poirier &lt;mathieu.poirier@linaro.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Robert Walker &lt;robert.walker@arm.com&gt;
Cc: Suzuki K Poulouse &lt;suzuki.poulose@arm.com&gt;
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20190322052255.GA4809@w-OptiPlex-7050
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin (Microsoft) &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf coresight: Do not test for libopencsd by default</title>
<updated>2019-04-05T20:34:37+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2019-02-12T17:37:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2392dcb54ad2512d67e11e6669aaa0e12048f427'/>
<id>2392dcb54ad2512d67e11e6669aaa0e12048f427</id>
<content type='text'>
[ Upstream commit 1c3b28fd7ae80c8f6bf1a09e1848e20a953c9ce4 ]

Since it is not yet that generally available, avoid testing for the
presence of libcoresight in the fast path test-all.bin feature test.

  # dnf search opencsd
  No matches found.
  # dnf search OpenCSD
  No matches found.
  # cat /etc/fedora-release
  Fedora release 29 (Twenty Nine)
  #

I.e. right now, in my system test-all.bin is failing all the time since
Fedora29 doesn't have libopencsd available:

  $ cat /tmp/build/perf/feature/test-all.make.output
  In file included from test-all.c:174:
  test-libopencsd.c:2:10: fatal error: opencsd/c_api/opencsd_c_api.h: No such file or directory
   #include &lt;opencsd/c_api/opencsd_c_api.h&gt;
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.

See:

  6ab2b762befd ("perf build: Disable libbabeltrace check by default")

For the rationale, as soon as libopencsd becomes more generally packaged
and available, we do the same thing we did with babeltrace, enabling it
by default, as done in:

  24787afbcd01 ("perf tools: Enable LIBBABELTRACE by default")

For now, to explicitely ask for opencsd, make sure you have it installed
and use:

   make -C tools/perf CORESIGHT=1

The feature test output will be there as an empty file:

  $ ls -la /tmp/build/perf/feature/test-libopencsd.make.output

Because the binary used for the feature check was successfully built:

  $ ls -la /tmp/build/perf/feature/test-libopencsd.bin
  -rwxrwxr-x. 1 acme acme 18336 Feb 12 14:49 /tmp/build/perf/feature/test-libopencsd.bin
  $ ldd /tmp/build/perf/feature/test-libopencsd.bin
	linux-vdso.so.1 (0x00007fffe18cc000)
	libopencsd_c_api.so.0 =&gt; /lib64/libopencsd_c_api.so.0 (0x00007fb8e67f6000)
	libopencsd.so.0 =&gt; /lib64/libopencsd.so.0 (0x00007fb8e676f000)
	libc.so.6 =&gt; /lib64/libc.so.6 (0x00007fb8e65a9000)
	libstdc++.so.6 =&gt; /lib64/libstdc++.so.6 (0x00007fb8e6411000)
	libm.so.6 =&gt; /lib64/libm.so.6 (0x00007fb8e628d000)
	libgcc_s.so.1 =&gt; /lib64/libgcc_s.so.1 (0x00007fb8e6272000)
	/lib64/ld-linux-x86-64.so.2 (0x00007fb8e6828000)
  $

And the resulting perf binary will be linked with it:

  -rw-rw-r--. 1 acme acme 0 Feb 12 14:49 /tmp/build/perf/feature/test-libopencsd.make.output
  $ ldd ~/bin/perf | grep opencsd
	libopencsd_c_api.so.0 =&gt; /lib64/libopencsd_c_api.so.0 (0x00007fd43097f000)
	libopencsd.so.0 =&gt; /lib64/libopencsd.so.0 (0x00007fd4308f8000)
  $

To make sure this gets built before pushing things upstream I have a
ubuntu:19.04-x-arm64 container that has:

  [root@quaco x-arm64]# grep CORESIGHT Dockerfile
  ENV EXTRA_MAKE_ARGS=CORESIGHT=1
  [root@quaco x-arm64]#

So that I always build with libopencsd before pushing things upstream.

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Kim Phillips &lt;kim.phillips@arm.com&gt;
Cc: linux-arm-kernel@lists.infradead.org
Cc: Mathieu Poirier &lt;mathieu.poirier@linaro.org&gt;
Cc: Mike Leach &lt;mike.leach@arm.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Suzuki Poulouse &lt;suzuki.poulose@arm.com&gt;
Link: https://lkml.kernel.org/n/tip-20vyy39jw9jgrijesi30fgox@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 1c3b28fd7ae80c8f6bf1a09e1848e20a953c9ce4 ]

Since it is not yet that generally available, avoid testing for the
presence of libcoresight in the fast path test-all.bin feature test.

  # dnf search opencsd
  No matches found.
  # dnf search OpenCSD
  No matches found.
  # cat /etc/fedora-release
  Fedora release 29 (Twenty Nine)
  #

I.e. right now, in my system test-all.bin is failing all the time since
Fedora29 doesn't have libopencsd available:

  $ cat /tmp/build/perf/feature/test-all.make.output
  In file included from test-all.c:174:
  test-libopencsd.c:2:10: fatal error: opencsd/c_api/opencsd_c_api.h: No such file or directory
   #include &lt;opencsd/c_api/opencsd_c_api.h&gt;
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.

See:

  6ab2b762befd ("perf build: Disable libbabeltrace check by default")

For the rationale, as soon as libopencsd becomes more generally packaged
and available, we do the same thing we did with babeltrace, enabling it
by default, as done in:

  24787afbcd01 ("perf tools: Enable LIBBABELTRACE by default")

For now, to explicitely ask for opencsd, make sure you have it installed
and use:

   make -C tools/perf CORESIGHT=1

The feature test output will be there as an empty file:

  $ ls -la /tmp/build/perf/feature/test-libopencsd.make.output

Because the binary used for the feature check was successfully built:

  $ ls -la /tmp/build/perf/feature/test-libopencsd.bin
  -rwxrwxr-x. 1 acme acme 18336 Feb 12 14:49 /tmp/build/perf/feature/test-libopencsd.bin
  $ ldd /tmp/build/perf/feature/test-libopencsd.bin
	linux-vdso.so.1 (0x00007fffe18cc000)
	libopencsd_c_api.so.0 =&gt; /lib64/libopencsd_c_api.so.0 (0x00007fb8e67f6000)
	libopencsd.so.0 =&gt; /lib64/libopencsd.so.0 (0x00007fb8e676f000)
	libc.so.6 =&gt; /lib64/libc.so.6 (0x00007fb8e65a9000)
	libstdc++.so.6 =&gt; /lib64/libstdc++.so.6 (0x00007fb8e6411000)
	libm.so.6 =&gt; /lib64/libm.so.6 (0x00007fb8e628d000)
	libgcc_s.so.1 =&gt; /lib64/libgcc_s.so.1 (0x00007fb8e6272000)
	/lib64/ld-linux-x86-64.so.2 (0x00007fb8e6828000)
  $

And the resulting perf binary will be linked with it:

  -rw-rw-r--. 1 acme acme 0 Feb 12 14:49 /tmp/build/perf/feature/test-libopencsd.make.output
  $ ldd ~/bin/perf | grep opencsd
	libopencsd_c_api.so.0 =&gt; /lib64/libopencsd_c_api.so.0 (0x00007fd43097f000)
	libopencsd.so.0 =&gt; /lib64/libopencsd.so.0 (0x00007fd4308f8000)
  $

To make sure this gets built before pushing things upstream I have a
ubuntu:19.04-x-arm64 container that has:

  [root@quaco x-arm64]# grep CORESIGHT Dockerfile
  ENV EXTRA_MAKE_ARGS=CORESIGHT=1
  [root@quaco x-arm64]#

So that I always build with libopencsd before pushing things upstream.

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Kim Phillips &lt;kim.phillips@arm.com&gt;
Cc: linux-arm-kernel@lists.infradead.org
Cc: Mathieu Poirier &lt;mathieu.poirier@linaro.org&gt;
Cc: Mike Leach &lt;mike.leach@arm.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Suzuki Poulouse &lt;suzuki.poulose@arm.com&gt;
Link: https://lkml.kernel.org/n/tip-20vyy39jw9jgrijesi30fgox@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools build: Add test-reallocarray.c to test-all.c to fix the build</title>
<updated>2019-04-05T20:34:37+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2019-02-14T15:01:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=336eb093ba1635bb50f117eeb85a16ab40d37afb'/>
<id>336eb093ba1635bb50f117eeb85a16ab40d37afb</id>
<content type='text'>
[ Upstream commit a96c03e8cdcf123384319f312d0a08a7a760bb35 ]

When a test is in the FEATURE_TESTS_BASIC list in tools/build/Makefile.feature
must be added to tools/build/feature/test-all.c, because the successfull
compilation and linking of that test-all.bin file means that all the
features listed in FEATURE_TESTS_BASIC are present in the system, so we
don't have to go on feature by feature test building them.

Since reallocarray() is expected to be present in modern systems, it has
a place in FEATURE_TESTS_BASIC, so that we speed up the build process
building just that file.

For older systems, such as ubuntu:16.04 (build failure reported by Jin
Yao) debian:8, and for the current flagship RHEL distro, RHEL7, the
build will fail as test-all.bin (without test-reallocarray.c included)
passes but reallocarray() isn't present, making the build fail with:

    CC       /tmp/build/perf/libbpf.o
    MKDIR    /tmp/build/perf/fs/
    CC       /tmp/build/perf/fs/tracing_path.o
    LD       /tmp/build/perf/fd/libapi-in.o
    CC       /tmp/build/perf/bpf.o
  libbpf.c: In function 'bpf_object__add_program':
  libbpf.c:367:10: error: implicit declaration of function 'reallocarray' [-Werror=implicit-function-declaration]
    progs = reallocarray(progs, nr_progs + 1, sizeof(progs[0]));
            ^
  libbpf.c:367:2: error: nested extern declaration of 'reallocarray' [-Werror=nested-externs]
    progs = reallocarray(progs, nr_progs + 1, sizeof(progs[0]));
    ^
  libbpf.c:367:8: error: assignment makes pointer from integer without a cast [-Werror=int-conversion]
    progs = reallocarray(progs, nr_progs + 1, sizeof(progs[0]));
          ^
  libbpf.c: In function 'bpf_object__elf_collect':
  libbpf.c:887:10: error: assignment makes pointer from integer without a cast [-Werror=int-conversion]
      reloc = reallocarray(reloc, nr_reloc,
            ^
  libbpf.c: In function 'bpf_program__reloc_text':
  libbpf.c:1394:12: error: assignment makes pointer from integer without a cast [-Werror=int-conversion]
     new_insn = reallocarray(prog-&gt;insns, new_cnt, sizeof(*insn));
              ^
    CC       /tmp/build/perf/nlattr.o

Even with:

  $ grep reallocarray /tmp/build/perf/FEATURE-DUMP
  feature-reallocarray=1
  $

Which ubuntu:16.04.5 LTS doesn't have:

  perfbuilder@38a153a1bba8:/$ head -2 /etc/os-release
  NAME="Ubuntu"
  VERSION="16.04.5 LTS (Xenial Xerus)"
  perfbuilder@38a153a1bba8:/$ find /usr/include/ -name "*.h" | xargs grep -w reallocarray
  perfbuilder@38a153a1bba8:/$

Fix it by including it to test-all.c, which ends up forcing the
individual tests to be triggered and for the build process to notice
that indeed reallocarray() is not there:

  perfbuilder@38a153a1bba8:/$ cat /tmp/build/perf/feature/test-all.make.output
  In file included from test-all.c:178:0:
  test-reallocarray.c: In function 'main_test_reallocarray':
  test-reallocarray.c:7:11: error: implicit declaration of function 'reallocarray' [-Werror=implicit-function-declaration]
    return !!reallocarray(NULL, 1, 1);
             ^
  cc1: all warnings being treated as errors
  perfbuilder@38a153a1bba8:/$

That is the only test that is failing on Ubuntu 16.03.5 LTS, so all
tests are forced:

  perfbuilder@38a153a1bba8:/tmp/build/perf/feature$ ls -lSr *.make.output
  &lt;SNIP successful tests&gt;
  -rw-r--r--. 1 perfbuilder perfbuilder   0 Feb 14 15:00 test-dwarf.make.output
  -rw-r--r--. 1 perfbuilder perfbuilder   0 Feb 14 14:16 test-cplus-demangle.make.output
  -rw-r--r--. 1 perfbuilder perfbuilder   0 Feb 14 15:00 test-bpf.make.output
  -rw-r--r--. 1 perfbuilder perfbuilder   0 Feb 14 15:00 test-backtrace.make.output
  -rw-r--r--. 1 perfbuilder perfbuilder 104 Feb 14 15:00 test-bionic.make.output
  -rw-r--r--. 1 perfbuilder perfbuilder 107 Feb 14 15:00 test-libunwind-x86.make.output
  -rw-r--r--. 1 perfbuilder perfbuilder 115 Feb 14 15:00 test-libunwind-aarch64.make.output
  -rw-r--r--. 1 perfbuilder perfbuilder 122 Feb 14 15:00 test-libbabeltrace.make.output
  -rw-r--r--. 1 perfbuilder perfbuilder 254 Feb 14 15:00 test-reallocarray.make.output
  -rw-r--r--. 1 perfbuilder perfbuilder 312 Feb 14 15:00 test-all.make.output
  perfbuilder@38a153a1bba8:/tmp/build/perf/feature$

And that reallocarray() one shows:

  perfbuilder@38a153a1bba8:/tmp/build/perf/feature$ cat test-reallocarray.make.output
  test-reallocarray.c: In function 'main':
  test-reallocarray.c:7:11: error: implicit declaration of function 'reallocarray' [-Werror=implicit-function-declaration]
    return !!reallocarray(NULL, 1, 1);
             ^
  cc1: all warnings being treated as errors
  perfbuilder@38a153a1bba8:/tmp/build/perf/feature$

Which now generates the expected result:

  perfbuilder@38a153a1bba8:~$ grep reallocarray /tmp/build/perf/FEATURE-DUMP
  feature-reallocarray=0
  perfbuilder@38a153a1bba8:~$

The fallback mechanism kicks in and libbpf and perf are again buildable
in systems without reallocarray():

  $ cat tools/include/tools/libc_compat.h
  // SPDX-License-Identifier: (LGPL-2.0+ OR BSD-2-Clause)
  /* Copyright (C) 2018 Netronome Systems, Inc. */

  #ifndef __TOOLS_LIBC_COMPAT_H
  #define __TOOLS_LIBC_COMPAT_H

  #include &lt;stdlib.h&gt;
  #include &lt;linux/overflow.h&gt;

  #ifdef COMPAT_NEED_REALLOCARRAY
  static inline void *reallocarray(void *ptr, size_t nmemb, size_t size)
  {
	  size_t bytes;

	  if (unlikely(check_mul_overflow(nmemb, size, &amp;bytes)))
		  return NULL;
	  return realloc(ptr, bytes);
  }
  #endif
  #endif
  $

Reported-by: Jin Yao &lt;yao.jin@linux.intel.com&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Alexei Starovoitov &lt;ast@fb.com&gt;
Cc: Andrii Nakryiko &lt;andrii.nakryiko@gmail.com&gt;
Cc: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Cc: Jakub Kicinski &lt;jakub.kicinski@netronome.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Song Liu &lt;songliubraving@fb.com&gt;
Cc: Yonghong Song &lt;yhs@fb.com&gt;
Fixes: 531b014e7a2f ("tools: bpf: make use of reallocarray")
Link: https://lkml.kernel.org/n/tip-aonqku8axii8rxki5g11w40b@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit a96c03e8cdcf123384319f312d0a08a7a760bb35 ]

When a test is in the FEATURE_TESTS_BASIC list in tools/build/Makefile.feature
must be added to tools/build/feature/test-all.c, because the successfull
compilation and linking of that test-all.bin file means that all the
features listed in FEATURE_TESTS_BASIC are present in the system, so we
don't have to go on feature by feature test building them.

Since reallocarray() is expected to be present in modern systems, it has
a place in FEATURE_TESTS_BASIC, so that we speed up the build process
building just that file.

For older systems, such as ubuntu:16.04 (build failure reported by Jin
Yao) debian:8, and for the current flagship RHEL distro, RHEL7, the
build will fail as test-all.bin (without test-reallocarray.c included)
passes but reallocarray() isn't present, making the build fail with:

    CC       /tmp/build/perf/libbpf.o
    MKDIR    /tmp/build/perf/fs/
    CC       /tmp/build/perf/fs/tracing_path.o
    LD       /tmp/build/perf/fd/libapi-in.o
    CC       /tmp/build/perf/bpf.o
  libbpf.c: In function 'bpf_object__add_program':
  libbpf.c:367:10: error: implicit declaration of function 'reallocarray' [-Werror=implicit-function-declaration]
    progs = reallocarray(progs, nr_progs + 1, sizeof(progs[0]));
            ^
  libbpf.c:367:2: error: nested extern declaration of 'reallocarray' [-Werror=nested-externs]
    progs = reallocarray(progs, nr_progs + 1, sizeof(progs[0]));
    ^
  libbpf.c:367:8: error: assignment makes pointer from integer without a cast [-Werror=int-conversion]
    progs = reallocarray(progs, nr_progs + 1, sizeof(progs[0]));
          ^
  libbpf.c: In function 'bpf_object__elf_collect':
  libbpf.c:887:10: error: assignment makes pointer from integer without a cast [-Werror=int-conversion]
      reloc = reallocarray(reloc, nr_reloc,
            ^
  libbpf.c: In function 'bpf_program__reloc_text':
  libbpf.c:1394:12: error: assignment makes pointer from integer without a cast [-Werror=int-conversion]
     new_insn = reallocarray(prog-&gt;insns, new_cnt, sizeof(*insn));
              ^
    CC       /tmp/build/perf/nlattr.o

Even with:

  $ grep reallocarray /tmp/build/perf/FEATURE-DUMP
  feature-reallocarray=1
  $

Which ubuntu:16.04.5 LTS doesn't have:

  perfbuilder@38a153a1bba8:/$ head -2 /etc/os-release
  NAME="Ubuntu"
  VERSION="16.04.5 LTS (Xenial Xerus)"
  perfbuilder@38a153a1bba8:/$ find /usr/include/ -name "*.h" | xargs grep -w reallocarray
  perfbuilder@38a153a1bba8:/$

Fix it by including it to test-all.c, which ends up forcing the
individual tests to be triggered and for the build process to notice
that indeed reallocarray() is not there:

  perfbuilder@38a153a1bba8:/$ cat /tmp/build/perf/feature/test-all.make.output
  In file included from test-all.c:178:0:
  test-reallocarray.c: In function 'main_test_reallocarray':
  test-reallocarray.c:7:11: error: implicit declaration of function 'reallocarray' [-Werror=implicit-function-declaration]
    return !!reallocarray(NULL, 1, 1);
             ^
  cc1: all warnings being treated as errors
  perfbuilder@38a153a1bba8:/$

That is the only test that is failing on Ubuntu 16.03.5 LTS, so all
tests are forced:

  perfbuilder@38a153a1bba8:/tmp/build/perf/feature$ ls -lSr *.make.output
  &lt;SNIP successful tests&gt;
  -rw-r--r--. 1 perfbuilder perfbuilder   0 Feb 14 15:00 test-dwarf.make.output
  -rw-r--r--. 1 perfbuilder perfbuilder   0 Feb 14 14:16 test-cplus-demangle.make.output
  -rw-r--r--. 1 perfbuilder perfbuilder   0 Feb 14 15:00 test-bpf.make.output
  -rw-r--r--. 1 perfbuilder perfbuilder   0 Feb 14 15:00 test-backtrace.make.output
  -rw-r--r--. 1 perfbuilder perfbuilder 104 Feb 14 15:00 test-bionic.make.output
  -rw-r--r--. 1 perfbuilder perfbuilder 107 Feb 14 15:00 test-libunwind-x86.make.output
  -rw-r--r--. 1 perfbuilder perfbuilder 115 Feb 14 15:00 test-libunwind-aarch64.make.output
  -rw-r--r--. 1 perfbuilder perfbuilder 122 Feb 14 15:00 test-libbabeltrace.make.output
  -rw-r--r--. 1 perfbuilder perfbuilder 254 Feb 14 15:00 test-reallocarray.make.output
  -rw-r--r--. 1 perfbuilder perfbuilder 312 Feb 14 15:00 test-all.make.output
  perfbuilder@38a153a1bba8:/tmp/build/perf/feature$

And that reallocarray() one shows:

  perfbuilder@38a153a1bba8:/tmp/build/perf/feature$ cat test-reallocarray.make.output
  test-reallocarray.c: In function 'main':
  test-reallocarray.c:7:11: error: implicit declaration of function 'reallocarray' [-Werror=implicit-function-declaration]
    return !!reallocarray(NULL, 1, 1);
             ^
  cc1: all warnings being treated as errors
  perfbuilder@38a153a1bba8:/tmp/build/perf/feature$

Which now generates the expected result:

  perfbuilder@38a153a1bba8:~$ grep reallocarray /tmp/build/perf/FEATURE-DUMP
  feature-reallocarray=0
  perfbuilder@38a153a1bba8:~$

The fallback mechanism kicks in and libbpf and perf are again buildable
in systems without reallocarray():

  $ cat tools/include/tools/libc_compat.h
  // SPDX-License-Identifier: (LGPL-2.0+ OR BSD-2-Clause)
  /* Copyright (C) 2018 Netronome Systems, Inc. */

  #ifndef __TOOLS_LIBC_COMPAT_H
  #define __TOOLS_LIBC_COMPAT_H

  #include &lt;stdlib.h&gt;
  #include &lt;linux/overflow.h&gt;

  #ifdef COMPAT_NEED_REALLOCARRAY
  static inline void *reallocarray(void *ptr, size_t nmemb, size_t size)
  {
	  size_t bytes;

	  if (unlikely(check_mul_overflow(nmemb, size, &amp;bytes)))
		  return NULL;
	  return realloc(ptr, bytes);
  }
  #endif
  #endif
  $

Reported-by: Jin Yao &lt;yao.jin@linux.intel.com&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Alexei Starovoitov &lt;ast@fb.com&gt;
Cc: Andrii Nakryiko &lt;andrii.nakryiko@gmail.com&gt;
Cc: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Cc: Jakub Kicinski &lt;jakub.kicinski@netronome.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Song Liu &lt;songliubraving@fb.com&gt;
Cc: Yonghong Song &lt;yhs@fb.com&gt;
Fixes: 531b014e7a2f ("tools: bpf: make use of reallocarray")
Link: https://lkml.kernel.org/n/tip-aonqku8axii8rxki5g11w40b@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf build: Don't unconditionally link the libbfd feature test to -liberty and -lz</title>
<updated>2018-12-21T12:42:46+00:00</updated>
<author>
<name>Stanislav Fomichev</name>
<email>sdf@google.com</email>
</author>
<published>2018-11-16T00:32:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=14541b1e7e723859ff2c75c6fc10cdbbec6b8c34'/>
<id>14541b1e7e723859ff2c75c6fc10cdbbec6b8c34</id>
<content type='text'>
Current libbfd feature test unconditionally links against -liberty and -lz.
While it's required on some systems (e.g. opensuse), it's completely
unnecessary on the others, where only -lbdf is sufficient (debian).
This patch streamlines (and renames) the following feature checks:

feature-libbfd           - only link against -lbfd (debian),
                           see commit 2cf9040714f3 ("perf tools: Fix bfd
			   dependency libraries detection")
feature-libbfd-liberty   - link against -lbfd and -liberty
feature-libbfd-liberty-z - link against -lbfd, -liberty and -lz (opensuse),
                           see commit 280e7c48c3b8 ("perf tools: fix BFD
			   detection on opensuse")

(feature-liberty{,-z} were renamed to feature-libbfd-liberty{,z}
for clarity)

The main motivation is to fix this feature test for bpftool which is
currently broken on debian (libbfd feature shows OFF, but we still
unconditionally link against -lbfd and it works).

Tested on debian with only -lbfd installed (without -liberty); I'd
appreciate if somebody on the other systems can test this new detection
method.

Signed-off-by: Stanislav Fomichev &lt;sdf@google.com&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Mathieu Poirier &lt;mathieu.poirier@linaro.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lkml.kernel.org/r/4dfc634cfcfb236883971b5107cf3c28ec8a31be.1542328222.git.sdf@google.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>
Current libbfd feature test unconditionally links against -liberty and -lz.
While it's required on some systems (e.g. opensuse), it's completely
unnecessary on the others, where only -lbdf is sufficient (debian).
This patch streamlines (and renames) the following feature checks:

feature-libbfd           - only link against -lbfd (debian),
                           see commit 2cf9040714f3 ("perf tools: Fix bfd
			   dependency libraries detection")
feature-libbfd-liberty   - link against -lbfd and -liberty
feature-libbfd-liberty-z - link against -lbfd, -liberty and -lz (opensuse),
                           see commit 280e7c48c3b8 ("perf tools: fix BFD
			   detection on opensuse")

(feature-liberty{,-z} were renamed to feature-libbfd-liberty{,z}
for clarity)

The main motivation is to fix this feature test for bpftool which is
currently broken on debian (libbfd feature shows OFF, but we still
unconditionally link against -lbfd and it works).

Tested on debian with only -lbfd installed (without -liberty); I'd
appreciate if somebody on the other systems can test this new detection
method.

Signed-off-by: Stanislav Fomichev &lt;sdf@google.com&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Mathieu Poirier &lt;mathieu.poirier@linaro.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lkml.kernel.org/r/4dfc634cfcfb236883971b5107cf3c28ec8a31be.1542328222.git.sdf@google.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf cs-etm: Support for ARM A32/T32 instruction sets in CoreSight trace</title>
<updated>2018-12-17T17:56:18+00:00</updated>
<author>
<name>Robert Walker</name>
<email>robert.walker@arm.com</email>
</author>
<published>2018-12-03T12:18:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a7ee4d625ede4f62146ff3bb2aeee074e4cf5fa1'/>
<id>a7ee4d625ede4f62146ff3bb2aeee074e4cf5fa1</id>
<content type='text'>
This patch adds support for generating instruction samples from trace of
AArch32 programs using the A32 and T32 instruction sets.

T32 has variable 2 or 4 byte instruction size, so the conversion between
addresses and instruction counts requires extra information from the
trace decoder, requiring version 0.10.0 of OpenCSD.  A check for the
OpenCSD library version has been added to the feature check for OpenCSD.

Signed-off-by: Robert Walker &lt;robert.walker@arm.com&gt;
Reviewed-by: Mathieu Poirier &lt;mathieu.poirier@linaro.org&gt;
Tested-by: Leo Yan &lt;leo.yan@linaro.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1543839526-30348-1-git-send-email-robert.walker@arm.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>
This patch adds support for generating instruction samples from trace of
AArch32 programs using the A32 and T32 instruction sets.

T32 has variable 2 or 4 byte instruction size, so the conversion between
addresses and instruction counts requires extra information from the
trace decoder, requiring version 0.10.0 of OpenCSD.  A check for the
OpenCSD library version has been added to the feature check for OpenCSD.

Signed-off-by: Robert Walker &lt;robert.walker@arm.com&gt;
Reviewed-by: Mathieu Poirier &lt;mathieu.poirier@linaro.org&gt;
Tested-by: Leo Yan &lt;leo.yan@linaro.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1543839526-30348-1-git-send-email-robert.walker@arm.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools build feature: Check if libaio is available</title>
<updated>2018-12-17T17:54:54+00:00</updated>
<author>
<name>Alexey Budankov</name>
<email>alexey.budankov@linux.intel.com</email>
</author>
<published>2018-11-06T09:03:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2a07d814747b386feec7d7150fe519feb2a2a5f2'/>
<id>2a07d814747b386feec7d7150fe519feb2a2a5f2</id>
<content type='text'>
This will be used by 'perf record' to speed up reading the perf ring
buffer.

Committer testing:

  $ make -C tools/perf O=/tmp/build/perf
  make: Entering directory '/home/acme/git/perf/tools/perf'
    BUILD:   Doing 'make -j8' parallel build

  Auto-detecting system features:
  ...                         dwarf: [ on  ]
  ...            dwarf_getlocations: [ on  ]
  ...                         glibc: [ on  ]
  ...                          gtk2: [ OFF ]
  ...                      libaudit: [ OFF ]
  ...                        libbfd: [ OFF ]
  ...                        libelf: [ on  ]
  ...                       libnuma: [ OFF ]
  ...        numa_num_possible_cpus: [ OFF ]
  ...                       libperl: [ OFF ]
  ...                     libpython: [ OFF ]
  ...                      libslang: [ on  ]
  ...                     libcrypto: [ on  ]
  ...                     libunwind: [ on  ]
  ...            libdw-dwarf-unwind: [ on  ]
  ...                          zlib: [ on  ]
  ...                          lzma: [ on  ]
  ...                     get_cpuid: [ on  ]
  ...                           bpf: [ on  ]
  ...                        libaio: [ on  ]

  $ ls -la /tmp/build/perf/feature/test-libaio.*
  -rwxrwxr-x. 1 acme acme 18296 Nov 26 08:49 /tmp/build/perf/feature/test-libaio.bin
  -rw-rw-r--. 1 acme acme  1165 Nov 26 08:49 /tmp/build/perf/feature/test-libaio.d
  -rw-rw-r--. 1 acme acme     0 Nov 26 08:49 /tmp/build/perf/feature/test-libaio.make.output
  $
  $ grep -i aio /tmp/build/perf/FEATURE-DUMP
  feature-libaio=1
  $

Signed-off-by: Alexey Budankov &lt;alexey.budankov@linux.intel.com&gt;
Tested-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@redhat.com&gt;
Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lkml.kernel.org/r/5fcda10c-6c63-68df-383a-c6d9e5d1f918@linux.intel.com
[ split from a larger patch ]
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>
This will be used by 'perf record' to speed up reading the perf ring
buffer.

Committer testing:

  $ make -C tools/perf O=/tmp/build/perf
  make: Entering directory '/home/acme/git/perf/tools/perf'
    BUILD:   Doing 'make -j8' parallel build

  Auto-detecting system features:
  ...                         dwarf: [ on  ]
  ...            dwarf_getlocations: [ on  ]
  ...                         glibc: [ on  ]
  ...                          gtk2: [ OFF ]
  ...                      libaudit: [ OFF ]
  ...                        libbfd: [ OFF ]
  ...                        libelf: [ on  ]
  ...                       libnuma: [ OFF ]
  ...        numa_num_possible_cpus: [ OFF ]
  ...                       libperl: [ OFF ]
  ...                     libpython: [ OFF ]
  ...                      libslang: [ on  ]
  ...                     libcrypto: [ on  ]
  ...                     libunwind: [ on  ]
  ...            libdw-dwarf-unwind: [ on  ]
  ...                          zlib: [ on  ]
  ...                          lzma: [ on  ]
  ...                     get_cpuid: [ on  ]
  ...                           bpf: [ on  ]
  ...                        libaio: [ on  ]

  $ ls -la /tmp/build/perf/feature/test-libaio.*
  -rwxrwxr-x. 1 acme acme 18296 Nov 26 08:49 /tmp/build/perf/feature/test-libaio.bin
  -rw-rw-r--. 1 acme acme  1165 Nov 26 08:49 /tmp/build/perf/feature/test-libaio.d
  -rw-rw-r--. 1 acme acme     0 Nov 26 08:49 /tmp/build/perf/feature/test-libaio.make.output
  $
  $ grep -i aio /tmp/build/perf/FEATURE-DUMP
  feature-libaio=1
  $

Signed-off-by: Alexey Budankov &lt;alexey.budankov@linux.intel.com&gt;
Tested-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@redhat.com&gt;
Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lkml.kernel.org/r/5fcda10c-6c63-68df-383a-c6d9e5d1f918@linux.intel.com
[ split from a larger patch ]
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf jvmti: Separate jvmti cmlr check</title>
<updated>2018-11-22T01:39:58+00:00</updated>
<author>
<name>Jiri Olsa</name>
<email>jolsa@kernel.org</email>
</author>
<published>2018-11-21T15:43:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=dd1d0044dd1c1bf84a9b3e1f24e43347b26b96a0'/>
<id>dd1d0044dd1c1bf84a9b3e1f24e43347b26b96a0</id>
<content type='text'>
The Compiled Method Load Record (cmlr) is JDK specific interface to
access JVM stack info. This makes the jvmti agent code not compile under
another jdk, which does not support that.

Separating jvmti cmlr check into special feature check, and adding
HAVE_JVMTI_CMLR macro to indicate that.

Mark cmlr code in jvmti/libjvmti.c with HAVE_JVMTI_CMLR, so we can
compile it on system without cmlr support.

This change makes the jvmti compile with java-1.8.0-ibm package. It's
without the line numbers support, but the rest works.

Adding NO_JVMTI_CMLR compile variable for testing.

Signed-off-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Ben Gainey &lt;ben.gainey@arm.com&gt;
Cc: Gustavo Luiz Duarte &lt;gduarte@redhat.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Link: http://lkml.kernel.org/r/20181121154341.21521-1-jolsa@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 Compiled Method Load Record (cmlr) is JDK specific interface to
access JVM stack info. This makes the jvmti agent code not compile under
another jdk, which does not support that.

Separating jvmti cmlr check into special feature check, and adding
HAVE_JVMTI_CMLR macro to indicate that.

Mark cmlr code in jvmti/libjvmti.c with HAVE_JVMTI_CMLR, so we can
compile it on system without cmlr support.

This change makes the jvmti compile with java-1.8.0-ibm package. It's
without the line numbers support, but the rest works.

Adding NO_JVMTI_CMLR compile variable for testing.

Signed-off-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Ben Gainey &lt;ben.gainey@arm.com&gt;
Cc: Gustavo Luiz Duarte &lt;gduarte@redhat.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Link: http://lkml.kernel.org/r/20181121154341.21521-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools build feature: Check if eventfd() is available</title>
<updated>2018-11-22T01:25:44+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2018-11-21T20:42:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=11c6cbe706f218a8dc7e1f962f12b3a52ddd33a9'/>
<id>11c6cbe706f218a8dc7e1f962f12b3a52ddd33a9</id>
<content type='text'>
A new 'perf bench epoll' will use this, and to disable it for older
systems, add a feature test for this API.

This is just a simple program that if successfully compiled, means that
the feature is present, at least at the library level, in a build that
sets the output directory to /tmp/build/perf (using O=/tmp/build/perf),
we end up with:

  $ ls -la /tmp/build/perf/feature/test-eventfd*
  -rwxrwxr-x. 1 acme acme 8176 Nov 21 15:58 /tmp/build/perf/feature/test-eventfd.bin
  -rw-rw-r--. 1 acme acme  588 Nov 21 15:58 /tmp/build/perf/feature/test-eventfd.d
  -rw-rw-r--. 1 acme acme    0 Nov 21 15:58 /tmp/build/perf/feature/test-eventfd.make.output
  $ ldd /tmp/build/perf/feature/test-eventfd.bin
	  linux-vdso.so.1 (0x00007fff3bf3f000)
	  libc.so.6 =&gt; /lib64/libc.so.6 (0x00007fa984061000)
	  /lib64/ld-linux-x86-64.so.2 (0x00007fa984417000)
  $ grep eventfd -A 2 -B 2 /tmp/build/perf/FEATURE-DUMP
  feature-dwarf=1
  feature-dwarf_getlocations=1
  feature-eventfd=1
  feature-fortify-source=1
  feature-sync-compare-and-swap=1
  $

The main thing here is that in the end we'll have -DHAVE_EVENTFD in
CFLAGS, and then the 'perf bench' entry needing that API can be
selectively pruned.

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Davidlohr Bueso &lt;dbueso@suse.de&gt;
Cc: Jason Baron &lt;jbaron@akamai.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: https://lkml.kernel.org/n/tip-wkeldwob7dpx6jvtuzl8164k@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>
A new 'perf bench epoll' will use this, and to disable it for older
systems, add a feature test for this API.

This is just a simple program that if successfully compiled, means that
the feature is present, at least at the library level, in a build that
sets the output directory to /tmp/build/perf (using O=/tmp/build/perf),
we end up with:

  $ ls -la /tmp/build/perf/feature/test-eventfd*
  -rwxrwxr-x. 1 acme acme 8176 Nov 21 15:58 /tmp/build/perf/feature/test-eventfd.bin
  -rw-rw-r--. 1 acme acme  588 Nov 21 15:58 /tmp/build/perf/feature/test-eventfd.d
  -rw-rw-r--. 1 acme acme    0 Nov 21 15:58 /tmp/build/perf/feature/test-eventfd.make.output
  $ ldd /tmp/build/perf/feature/test-eventfd.bin
	  linux-vdso.so.1 (0x00007fff3bf3f000)
	  libc.so.6 =&gt; /lib64/libc.so.6 (0x00007fa984061000)
	  /lib64/ld-linux-x86-64.so.2 (0x00007fa984417000)
  $ grep eventfd -A 2 -B 2 /tmp/build/perf/FEATURE-DUMP
  feature-dwarf=1
  feature-dwarf_getlocations=1
  feature-eventfd=1
  feature-fortify-source=1
  feature-sync-compare-and-swap=1
  $

The main thing here is that in the end we'll have -DHAVE_EVENTFD in
CFLAGS, and then the 'perf bench' entry needing that API can be
selectively pruned.

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Davidlohr Bueso &lt;dbueso@suse.de&gt;
Cc: Jason Baron &lt;jbaron@akamai.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: https://lkml.kernel.org/n/tip-wkeldwob7dpx6jvtuzl8164k@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools build feature: Check if get_current_dir_name() is available</title>
<updated>2018-11-19T20:12:17+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2018-11-19T19:56:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8feb8efef97a134933620071e0b6384cb3238b4e'/>
<id>8feb8efef97a134933620071e0b6384cb3238b4e</id>
<content type='text'>
As the namespace support code will use this, which is not available in
some non _GNU_SOURCE libraries such as Android's bionic used in my
container build tests (r12b and r15c at the moment).

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: https://lkml.kernel.org/n/tip-x56ypm940pwclwu45d7jfj47@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>
As the namespace support code will use this, which is not available in
some non _GNU_SOURCE libraries such as Android's bionic used in my
container build tests (r12b and r15c at the moment).

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: https://lkml.kernel.org/n/tip-x56ypm940pwclwu45d7jfj47@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools: bpf: make use of reallocarray</title>
<updated>2018-07-11T20:13:34+00:00</updated>
<author>
<name>Jakub Kicinski</name>
<email>jakub.kicinski@netronome.com</email>
</author>
<published>2018-07-10T21:43:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=531b014e7a2fedaeff0b19b2934d830cd4b35dc0'/>
<id>531b014e7a2fedaeff0b19b2934d830cd4b35dc0</id>
<content type='text'>
reallocarray() is a safer variant of realloc which checks for
multiplication overflow in case of array allocation.  Since it's
not available in Glibc &lt; 2.26 import kernel's overflow.h and
add a static inline implementation when needed.  Use feature
detection to probe for existence of reallocarray.

Signed-off-by: Jakub Kicinski &lt;jakub.kicinski@netronome.com&gt;
Reviewed-by: Quentin Monnet &lt;quentin.monnet@netronome.com&gt;
Reviewed-by: Jiong Wang &lt;jiong.wang@netronome.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>
reallocarray() is a safer variant of realloc which checks for
multiplication overflow in case of array allocation.  Since it's
not available in Glibc &lt; 2.26 import kernel's overflow.h and
add a static inline implementation when needed.  Use feature
detection to probe for existence of reallocarray.

Signed-off-by: Jakub Kicinski &lt;jakub.kicinski@netronome.com&gt;
Reviewed-by: Quentin Monnet &lt;quentin.monnet@netronome.com&gt;
Reviewed-by: Jiong Wang &lt;jiong.wang@netronome.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</pre>
</div>
</content>
</entry>
</feed>
