<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/tools/perf/Makefile.config, branch v6.16</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge remote-tracking branch 'torvalds/master' into perf-tools-next</title>
<updated>2025-05-07T15:51:38+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2025-05-07T15:51:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=8330d092f789ca7859042c80cbf3ea496bc53d99'/>
<id>8330d092f789ca7859042c80cbf3ea496bc53d99</id>
<content type='text'>
To pick up fixes from the latest perf-tools pull request from Namhyung
and get perf-tools-next in line with thinngs in other areas it uses,
like tools/lib/bpf, etc.

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>
To pick up fixes from the latest perf-tools pull request from Namhyung
and get perf-tools-next in line with thinngs in other areas it uses,
like tools/lib/bpf, etc.

Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf tools: Fix in-source libperf build</title>
<updated>2025-04-29T19:32:31+00:00</updated>
<author>
<name>James Clark</name>
<email>james.clark@linaro.org</email>
</author>
<published>2025-04-29T14:22:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=8988c4b91945173a6b5505764915d470f0238fdc'/>
<id>8988c4b91945173a6b5505764915d470f0238fdc</id>
<content type='text'>
When libperf is built alone in-source, $(OUTPUT) isn't set. This causes
the generated uapi path to resolve to '/../arch' which results in a
permissions error:

  mkdir: cannot create directory '/../arch': Permission denied

Fix it by removing the preceding '/..' which means that it gets
generated either in the tools/lib/perf part of the tree or the OUTPUT
folder. Some other rules that rely on OUTPUT further refine this
conditionally depending on whether it's an in-source or out-of-source
build, but I don't think we need the extra complexity here. And this
rule is slightly different to others because the header is needed by
both libperf and Perf. This is further complicated by the fact that Perf
always passes O=... to libperf even for in source builds, meaning that
OUTPUT isn't set consistently between projects.

Because we're no longer going one level up to try to generate the file
in the tools/ folder, Perf's include rule needs to descend into libperf.
Also fix the clean rule while we're here.

Reported-by: Thorsten Leemhuis &lt;linux@leemhuis.info&gt;
Closes: https://lore.kernel.org/linux-perf-users/7703f88e-ccb7-4c98-9da4-8aad224e780f@leemhuis.info/
Fixes: bfb713ea53c7 ("perf tools: Fix arm64 build by generating unistd_64.h")
Signed-off-by: James Clark &lt;james.clark@linaro.org&gt;
Tested-by: Thorsten Leemhuis &lt;linux@leemhuis.info&gt;
Link: https://lore.kernel.org/r/20250429-james-perf-fix-libperf-in-source-build-v1-1-a1a827ac15e5@linaro.org
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When libperf is built alone in-source, $(OUTPUT) isn't set. This causes
the generated uapi path to resolve to '/../arch' which results in a
permissions error:

  mkdir: cannot create directory '/../arch': Permission denied

Fix it by removing the preceding '/..' which means that it gets
generated either in the tools/lib/perf part of the tree or the OUTPUT
folder. Some other rules that rely on OUTPUT further refine this
conditionally depending on whether it's an in-source or out-of-source
build, but I don't think we need the extra complexity here. And this
rule is slightly different to others because the header is needed by
both libperf and Perf. This is further complicated by the fact that Perf
always passes O=... to libperf even for in source builds, meaning that
OUTPUT isn't set consistently between projects.

Because we're no longer going one level up to try to generate the file
in the tools/ folder, Perf's include rule needs to descend into libperf.
Also fix the clean rule while we're here.

Reported-by: Thorsten Leemhuis &lt;linux@leemhuis.info&gt;
Closes: https://lore.kernel.org/linux-perf-users/7703f88e-ccb7-4c98-9da4-8aad224e780f@leemhuis.info/
Fixes: bfb713ea53c7 ("perf tools: Fix arm64 build by generating unistd_64.h")
Signed-off-by: James Clark &lt;james.clark@linaro.org&gt;
Tested-by: Thorsten Leemhuis &lt;linux@leemhuis.info&gt;
Link: https://lore.kernel.org/r/20250429-james-perf-fix-libperf-in-source-build-v1-1-a1a827ac15e5@linaro.org
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf tools: Fix arm64 build by generating unistd_64.h</title>
<updated>2025-04-23T15:57:12+00:00</updated>
<author>
<name>James Clark</name>
<email>james.clark@linaro.org</email>
</author>
<published>2025-04-17T13:55:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=bfb713ea53c746b07ae69fe97fa9b5388e4f34f9'/>
<id>bfb713ea53c746b07ae69fe97fa9b5388e4f34f9</id>
<content type='text'>
Since pulling in the kernel changes in commit 22f72088ffe6 ("tools
headers: Update the syscall table with the kernel sources"), arm64 is
no longer using a generic syscall header and generates one from the
syscall table. Therefore we must also generate the syscall header for
arm64 before building Perf.

Add it as a dependency to libperf which uses one syscall number. Perf
uses more, but as libperf is a dependency of Perf it will be generated
for both.

Future platforms that need this will have to add their own syscall-y
targets in libperf manually. Unfortunately the arch specific files that
do this (e.g. arch/arm64/include/asm/Kbuild) can't easily be imported
into the Perf build. But Perf only needs a subset of the generated files
anyway, so redefining them is probably the correct thing to do.

Fixes: 22f72088ffe6 ("tools headers: Update the syscall table with the kernel sources")
Signed-off-by: James Clark &lt;james.clark@linaro.org&gt;
Tested-by: Harshit Mogalapalli &lt;harshit.m.mogalapalli@oracle.com&gt;
Link: https://lore.kernel.org/r/20250417-james-perf-fix-gen-syscall-v1-1-1d268c923901@linaro.org
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Since pulling in the kernel changes in commit 22f72088ffe6 ("tools
headers: Update the syscall table with the kernel sources"), arm64 is
no longer using a generic syscall header and generates one from the
syscall table. Therefore we must also generate the syscall header for
arm64 before building Perf.

Add it as a dependency to libperf which uses one syscall number. Perf
uses more, but as libperf is a dependency of Perf it will be generated
for both.

Future platforms that need this will have to add their own syscall-y
targets in libperf manually. Unfortunately the arch specific files that
do this (e.g. arch/arm64/include/asm/Kbuild) can't easily be imported
into the Perf build. But Perf only needs a subset of the generated files
anyway, so redefining them is probably the correct thing to do.

Fixes: 22f72088ffe6 ("tools headers: Update the syscall table with the kernel sources")
Signed-off-by: James Clark &lt;james.clark@linaro.org&gt;
Tested-by: Harshit Mogalapalli &lt;harshit.m.mogalapalli@oracle.com&gt;
Link: https://lore.kernel.org/r/20250417-james-perf-fix-gen-syscall-v1-1-1d268c923901@linaro.org
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf build: Warn when libdebuginfod devel files are not available</title>
<updated>2025-04-10T13:45:02+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2025-04-08T14:37:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4fce4b91fd1aabb326c46e237eb4b19ab72598f8'/>
<id>4fce4b91fd1aabb326c46e237eb4b19ab72598f8</id>
<content type='text'>
While working on 'perf version --build-options' I noticed that:

  $ perf version --build-options
  perf version 6.15.rc1.g312a07a00d31
                   aio: [ on  ]  # HAVE_AIO_SUPPORT
                   bpf: [ on  ]  # HAVE_LIBBPF_SUPPORT
         bpf_skeletons: [ on  ]  # HAVE_BPF_SKEL
            debuginfod: [ OFF ]  # HAVE_DEBUGINFOD_SUPPORT
  &lt;SNIP&gt;

And looking at tools/perf/Makefile.config I also noticed that it is not
opt-in, meaning we will attempt to build with it in all normal cases.

So add the usual warning at build time to let the user know that
something recommended is missing, now we see:

  Makefile.config:563: No elfutils/debuginfod.h found, no debuginfo server support, please install elfutils-debuginfod-client-devel or equivalent

And after following the recommendation:

  $ perf check feature debuginfod
            debuginfod: [ on  ]  # HAVE_DEBUGINFOD_SUPPORT
  $ ldd ~/bin/perf | grep debuginfo
	libdebuginfod.so.1 =&gt; /lib64/libdebuginfod.so.1 (0x00007fee5cf5f000)
  $

With this feature on several perf tools will fetch what is needed and
not require all the contents of the debuginfo packages, for instance:

  # rpm -qa | grep kernel-debuginfo
  # pahole --running_kernel_vmlinux
  pahole: couldn't find a vmlinux that matches the running kernel
  HINT: Maybe you're inside a container or missing a debuginfo package?
  #
  # perf trace -e open* perf probe --vars icmp_rcv
      0.000 ( 0.005 ms): perf/97391 openat(dfd: CWD, filename: "/etc/ld.so.cache", flags: RDONLY|CLOEXEC) = 3
      0.014 ( 0.004 ms): perf/97391 openat(dfd: CWD, filename: "/lib64/libm.so.6", flags: RDONLY|CLOEXEC) = 3
  &lt;SNIP&gt;
  32130.100 ( 0.008 ms): perf/97391 openat(dfd: CWD, filename: "/root/.cache/debuginfod_client/aa3c82b4a13f9c0e0301bebb20fe958c4db6f362/debuginfo") = 3
  &lt;SNIP&gt;
  Available variables at icmp_rcv
        @&lt;icmp_rcv+0&gt;
                struct sk_buff* skb
  &lt;SNIP&gt;
  #
  # pahole --running_kernel_vmlinux
  /root/.cache/debuginfod_client/aa3c82b4a13f9c0e0301bebb20fe958c4db6f362/debuginfo
  # file /root/.cache/debuginfod_client/aa3c82b4a13f9c0e0301bebb20fe958c4db6f362/debuginfo
  /root/.cache/debuginfod_client/aa3c82b4a13f9c0e0301bebb20fe958c4db6f362/debuginfo: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), statically linked, BuildID[sha1]=aa3c82b4a13f9c0e0301bebb20fe958c4db6f362, with debug_info, not stripped
  # ls -la /root/.cache/debuginfod_client/aa3c82b4a13f9c0e0301bebb20fe958c4db6f362/debuginfo
  -r--------. 1 root root 475401512 Mar 27 21:00 /root/.cache/debuginfod_client/aa3c82b4a13f9c0e0301bebb20fe958c4db6f362/debuginfo
  #

Then, cached:

  # perf stat --null perf probe --vars icmp_rcv
  Available variables at icmp_rcv
        @&lt;icmp_rcv+0&gt;
                struct sk_buff* skb

   Performance counter stats for 'perf probe --vars icmp_rcv':

       0.671389041 seconds time elapsed

       0.519176000 seconds user
       0.150860000 seconds sys

Fixes: c7a14fdcb3fa7736 ("perf build-ids: Fall back to debuginfod query if debuginfo not found")
Tested-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Dmitriy Vyukov &lt;dvyukov@google.com&gt;
Cc: Howard Chu &lt;howardchu95@gmail.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Frank Ch. Eigler &lt;fche@redhat.com&gt;
Link: https://lore.kernel.org/r/Z_dkNDj9EPFwPqq1@gmail.com
[ Folded patch from Ingo to have the debian/ubuntu devel package added build warning message ]
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>
While working on 'perf version --build-options' I noticed that:

  $ perf version --build-options
  perf version 6.15.rc1.g312a07a00d31
                   aio: [ on  ]  # HAVE_AIO_SUPPORT
                   bpf: [ on  ]  # HAVE_LIBBPF_SUPPORT
         bpf_skeletons: [ on  ]  # HAVE_BPF_SKEL
            debuginfod: [ OFF ]  # HAVE_DEBUGINFOD_SUPPORT
  &lt;SNIP&gt;

And looking at tools/perf/Makefile.config I also noticed that it is not
opt-in, meaning we will attempt to build with it in all normal cases.

So add the usual warning at build time to let the user know that
something recommended is missing, now we see:

  Makefile.config:563: No elfutils/debuginfod.h found, no debuginfo server support, please install elfutils-debuginfod-client-devel or equivalent

And after following the recommendation:

  $ perf check feature debuginfod
            debuginfod: [ on  ]  # HAVE_DEBUGINFOD_SUPPORT
  $ ldd ~/bin/perf | grep debuginfo
	libdebuginfod.so.1 =&gt; /lib64/libdebuginfod.so.1 (0x00007fee5cf5f000)
  $

With this feature on several perf tools will fetch what is needed and
not require all the contents of the debuginfo packages, for instance:

  # rpm -qa | grep kernel-debuginfo
  # pahole --running_kernel_vmlinux
  pahole: couldn't find a vmlinux that matches the running kernel
  HINT: Maybe you're inside a container or missing a debuginfo package?
  #
  # perf trace -e open* perf probe --vars icmp_rcv
      0.000 ( 0.005 ms): perf/97391 openat(dfd: CWD, filename: "/etc/ld.so.cache", flags: RDONLY|CLOEXEC) = 3
      0.014 ( 0.004 ms): perf/97391 openat(dfd: CWD, filename: "/lib64/libm.so.6", flags: RDONLY|CLOEXEC) = 3
  &lt;SNIP&gt;
  32130.100 ( 0.008 ms): perf/97391 openat(dfd: CWD, filename: "/root/.cache/debuginfod_client/aa3c82b4a13f9c0e0301bebb20fe958c4db6f362/debuginfo") = 3
  &lt;SNIP&gt;
  Available variables at icmp_rcv
        @&lt;icmp_rcv+0&gt;
                struct sk_buff* skb
  &lt;SNIP&gt;
  #
  # pahole --running_kernel_vmlinux
  /root/.cache/debuginfod_client/aa3c82b4a13f9c0e0301bebb20fe958c4db6f362/debuginfo
  # file /root/.cache/debuginfod_client/aa3c82b4a13f9c0e0301bebb20fe958c4db6f362/debuginfo
  /root/.cache/debuginfod_client/aa3c82b4a13f9c0e0301bebb20fe958c4db6f362/debuginfo: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), statically linked, BuildID[sha1]=aa3c82b4a13f9c0e0301bebb20fe958c4db6f362, with debug_info, not stripped
  # ls -la /root/.cache/debuginfod_client/aa3c82b4a13f9c0e0301bebb20fe958c4db6f362/debuginfo
  -r--------. 1 root root 475401512 Mar 27 21:00 /root/.cache/debuginfod_client/aa3c82b4a13f9c0e0301bebb20fe958c4db6f362/debuginfo
  #

Then, cached:

  # perf stat --null perf probe --vars icmp_rcv
  Available variables at icmp_rcv
        @&lt;icmp_rcv+0&gt;
                struct sk_buff* skb

   Performance counter stats for 'perf probe --vars icmp_rcv':

       0.671389041 seconds time elapsed

       0.519176000 seconds user
       0.150860000 seconds sys

Fixes: c7a14fdcb3fa7736 ("perf build-ids: Fall back to debuginfod query if debuginfo not found")
Tested-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Dmitriy Vyukov &lt;dvyukov@google.com&gt;
Cc: Howard Chu &lt;howardchu95@gmail.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Frank Ch. Eigler &lt;fche@redhat.com&gt;
Link: https://lore.kernel.org/r/Z_dkNDj9EPFwPqq1@gmail.com
[ Folded patch from Ingo to have the debian/ubuntu devel package added build warning message ]
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools build: Don't set libunwind as available if test-all.c build succeeds</title>
<updated>2025-04-10T13:43:43+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2025-04-04T18:37:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=6559b83e4e71ba77461c8d6e6af7b89693c8e677'/>
<id>6559b83e4e71ba77461c8d6e6af7b89693c8e677</id>
<content type='text'>
The tools/build/feature/test-all.c file tries to detect the expected,
most common set of libraries/features we expect to have available to
build perf with.

At some point libunwind was deemed not to be part of that set of
libries, but the patches making it to be opt-in ended up forgetting some
details, fix one more.

Testing it:

  $ rm -rf /tmp/build/$(basename $PWD)/ ; mkdir -p /tmp/build/$(basename $PWD)/
  $ rpm -q libunwind-devel
  libunwind-devel-1.8.0-3.fc40.x86_64
  $ make -k LIBUNWIND=1 CORESIGHT=1 O=/tmp/build/$(basename $PWD)/ -C tools/perf install-bin |&amp; grep unwind &amp;&amp; ldd ~/bin/perf | grep unwind
  ...                               libunwind: [ on  ]
    CC      /tmp/build/perf-tools-next/arch/x86/tests/dwarf-unwind.o
    CC      /tmp/build/perf-tools-next/arch/x86/util/unwind-libunwind.o
    CC      /tmp/build/perf-tools-next/util/arm64-frame-pointer-unwind-support.o
    CC      /tmp/build/perf-tools-next/tests/dwarf-unwind.o
    CC      /tmp/build/perf-tools-next/util/unwind-libunwind-local.o
    CC      /tmp/build/perf-tools-next/util/unwind-libunwind.o
	  libunwind-x86_64.so.8 =&gt; /lib64/libunwind-x86_64.so.8 (0x00007f615a549000)
	  libunwind.so.8 =&gt; /lib64/libunwind.so.8 (0x00007f615a52f000)
  $ sudo rpm -e libunwind-devel
  $ rm -rf /tmp/build/$(basename $PWD)/ ; mkdir -p /tmp/build/$(basename $PWD)/
  $ make -k LIBUNWIND=1 CORESIGHT=1 O=/tmp/build/$(basename $PWD)/ -C tools/perf install-bin |&amp; grep unwind &amp;&amp; ldd ~/bin/perf | grep unwind
  Makefile.config:653: No libunwind found. Please install libunwind-dev[el] &gt;= 1.1 and/or set LIBUNWIND_DIR
  ...                               libunwind: [ OFF ]
    CC      /tmp/build/perf-tools-next/arch/x86/tests/dwarf-unwind.o
    CC      /tmp/build/perf-tools-next/arch/x86/util/unwind-libdw.o
    CC      /tmp/build/perf-tools-next/util/arm64-frame-pointer-unwind-support.o
    CC      /tmp/build/perf-tools-next/tests/dwarf-unwind.o
    CC      /tmp/build/perf-tools-next/util/unwind-libdw.o
  $

Should be in a separate patch, but tired now, so also adding a message
about the need to use LIBUNWIND=1 in the output when its not available,
so done here as well.

So, now when the devel files are not available we get:

  $ make -k LIBUNWIND=1 CORESIGHT=1 O=/tmp/build/$(basename $PWD)/ -C tools/perf install-bin |&amp; grep unwind &amp;&amp; ldd ~/bin/perf | grep unwind
  Makefile.config:653: No libunwind found. Please install libunwind-dev[el] &gt;= 1.1 and/or set LIBUNWIND_DIR and set LIBUNWIND=1 in the make command line as it is opt-in now
  ...                               libunwind: [ OFF ]
  $

Fixes: 13e17c9ff49119aa ("perf build: Make libunwind opt-in rather than opt-out")
Reported-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Tested-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Dmitriy Vyukov &lt;dvyukov@google.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: James Clark &lt;james.clark@linaro.org&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: https://lore.kernel.org/r/Z_AnsW9oJzFbhIFC@x1
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 tools/build/feature/test-all.c file tries to detect the expected,
most common set of libraries/features we expect to have available to
build perf with.

At some point libunwind was deemed not to be part of that set of
libries, but the patches making it to be opt-in ended up forgetting some
details, fix one more.

Testing it:

  $ rm -rf /tmp/build/$(basename $PWD)/ ; mkdir -p /tmp/build/$(basename $PWD)/
  $ rpm -q libunwind-devel
  libunwind-devel-1.8.0-3.fc40.x86_64
  $ make -k LIBUNWIND=1 CORESIGHT=1 O=/tmp/build/$(basename $PWD)/ -C tools/perf install-bin |&amp; grep unwind &amp;&amp; ldd ~/bin/perf | grep unwind
  ...                               libunwind: [ on  ]
    CC      /tmp/build/perf-tools-next/arch/x86/tests/dwarf-unwind.o
    CC      /tmp/build/perf-tools-next/arch/x86/util/unwind-libunwind.o
    CC      /tmp/build/perf-tools-next/util/arm64-frame-pointer-unwind-support.o
    CC      /tmp/build/perf-tools-next/tests/dwarf-unwind.o
    CC      /tmp/build/perf-tools-next/util/unwind-libunwind-local.o
    CC      /tmp/build/perf-tools-next/util/unwind-libunwind.o
	  libunwind-x86_64.so.8 =&gt; /lib64/libunwind-x86_64.so.8 (0x00007f615a549000)
	  libunwind.so.8 =&gt; /lib64/libunwind.so.8 (0x00007f615a52f000)
  $ sudo rpm -e libunwind-devel
  $ rm -rf /tmp/build/$(basename $PWD)/ ; mkdir -p /tmp/build/$(basename $PWD)/
  $ make -k LIBUNWIND=1 CORESIGHT=1 O=/tmp/build/$(basename $PWD)/ -C tools/perf install-bin |&amp; grep unwind &amp;&amp; ldd ~/bin/perf | grep unwind
  Makefile.config:653: No libunwind found. Please install libunwind-dev[el] &gt;= 1.1 and/or set LIBUNWIND_DIR
  ...                               libunwind: [ OFF ]
    CC      /tmp/build/perf-tools-next/arch/x86/tests/dwarf-unwind.o
    CC      /tmp/build/perf-tools-next/arch/x86/util/unwind-libdw.o
    CC      /tmp/build/perf-tools-next/util/arm64-frame-pointer-unwind-support.o
    CC      /tmp/build/perf-tools-next/tests/dwarf-unwind.o
    CC      /tmp/build/perf-tools-next/util/unwind-libdw.o
  $

Should be in a separate patch, but tired now, so also adding a message
about the need to use LIBUNWIND=1 in the output when its not available,
so done here as well.

So, now when the devel files are not available we get:

  $ make -k LIBUNWIND=1 CORESIGHT=1 O=/tmp/build/$(basename $PWD)/ -C tools/perf install-bin |&amp; grep unwind &amp;&amp; ldd ~/bin/perf | grep unwind
  Makefile.config:653: No libunwind found. Please install libunwind-dev[el] &gt;= 1.1 and/or set LIBUNWIND_DIR and set LIBUNWIND=1 in the make command line as it is opt-in now
  ...                               libunwind: [ OFF ]
  $

Fixes: 13e17c9ff49119aa ("perf build: Make libunwind opt-in rather than opt-out")
Reported-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Tested-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Dmitriy Vyukov &lt;dvyukov@google.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: James Clark &lt;james.clark@linaro.org&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: https://lore.kernel.org/r/Z_AnsW9oJzFbhIFC@x1
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf build: filter all combinations of -flto for libperl</title>
<updated>2025-03-24T06:12:10+00:00</updated>
<author>
<name>Holger Hoffstätte</name>
<email>holger@applied-asynchrony.com</email>
</author>
<published>2025-03-21T08:20:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=9480cc14a95e3883f895b5a2baa8f6c0c199c604'/>
<id>9480cc14a95e3883f895b5a2baa8f6c0c199c604</id>
<content type='text'>
When enabling the libperl feature the build uses perl's build flags
(ccopts) but filters out various flags, e.g. for LTO.
While this is conceptually correct, it is insufficient in practice,
since only "-flto=auto" is filtered out. When perl itself is built with
"-flto" this can cause parts of perf being built with LTO and others
without, giving exciting build errors like e.g.:

   ../tools/perf/pmu-events/pmu-events.c:72851:(.text+0xb79): undefined
   reference to `strcmp_cpuid_str' collect2: error: ld returned 1 exit status

Fix this by filtering all matching flag values of -flto{=n,auto,..}.

Signed-off-by: Holger Hoffstätte &lt;holger@applied-asynchrony.com&gt;
Link: https://lore.kernel.org/r/20250321082038.27901-2-holger@applied-asynchrony.com
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When enabling the libperl feature the build uses perl's build flags
(ccopts) but filters out various flags, e.g. for LTO.
While this is conceptually correct, it is insufficient in practice,
since only "-flto=auto" is filtered out. When perl itself is built with
"-flto" this can cause parts of perf being built with LTO and others
without, giving exciting build errors like e.g.:

   ../tools/perf/pmu-events/pmu-events.c:72851:(.text+0xb79): undefined
   reference to `strcmp_cpuid_str' collect2: error: ld returned 1 exit status

Fix this by filtering all matching flag values of -flto{=n,auto,..}.

Signed-off-by: Holger Hoffstätte &lt;holger@applied-asynchrony.com&gt;
Link: https://lore.kernel.org/r/20250321082038.27901-2-holger@applied-asynchrony.com
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf: Always feature test reallocarray</title>
<updated>2025-01-31T22:45:19+00:00</updated>
<author>
<name>James Clark</name>
<email>james.clark@linaro.org</email>
</author>
<published>2025-01-29T15:44:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4c4c0724d6521a8092b7c16f8f210c5869d95b17'/>
<id>4c4c0724d6521a8092b7c16f8f210c5869d95b17</id>
<content type='text'>
This is also used in util/comm.c now, so instead of selectively doing
the feature test, always do it. If it's ever used anywhere else it's
less likely to cause another build failure.

This doesn't remove the need to manually include libc_compat.h, and
missing that will still cause an error for glibc &lt; 2.26. There isn't a
way to fix that without poisoning reallocarray like libbpf did, but that
has other downsides like making memory debugging tools less useful. So
for Perf keep it like this and we'll have to fix up any missed includes.

Fixes the following build error:

  util/comm.c:152:31: error: implicit declaration of function
                      'reallocarray' [-Wimplicit-function-declaration]
  152 |                         tmp = reallocarray(comm_strs-&gt;strs,
      |                               ^~~~~~~~~~~~

Fixes: 13ca628716c6 ("perf comm: Add reference count checking to 'struct comm_str'")
Reported-by: Ali Utku Selen &lt;ali.utku.selen@arm.com&gt;
Signed-off-by: James Clark &lt;james.clark@linaro.org&gt;
Reviewed-by: Ian Rogers &lt;irogers@google.com&gt;
Link: https://lore.kernel.org/r/20250129154405.777533-1-james.clark@linaro.org
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This is also used in util/comm.c now, so instead of selectively doing
the feature test, always do it. If it's ever used anywhere else it's
less likely to cause another build failure.

This doesn't remove the need to manually include libc_compat.h, and
missing that will still cause an error for glibc &lt; 2.26. There isn't a
way to fix that without poisoning reallocarray like libbpf did, but that
has other downsides like making memory debugging tools less useful. So
for Perf keep it like this and we'll have to fix up any missed includes.

Fixes the following build error:

  util/comm.c:152:31: error: implicit declaration of function
                      'reallocarray' [-Wimplicit-function-declaration]
  152 |                         tmp = reallocarray(comm_strs-&gt;strs,
      |                               ^~~~~~~~~~~~

Fixes: 13ca628716c6 ("perf comm: Add reference count checking to 'struct comm_str'")
Reported-by: Ali Utku Selen &lt;ali.utku.selen@arm.com&gt;
Signed-off-by: James Clark &lt;james.clark@linaro.org&gt;
Reviewed-by: Ian Rogers &lt;irogers@google.com&gt;
Link: https://lore.kernel.org/r/20250129154405.777533-1-james.clark@linaro.org
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf tools: Remove dependency on libaudit</title>
<updated>2025-01-10T13:59:42+00:00</updated>
<author>
<name>Charlie Jenkins</name>
<email>charlie@rivosinc.com</email>
</author>
<published>2025-01-09T02:36:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=3cc550f5bbcf54abeeae400b33f618407a0c99f0'/>
<id>3cc550f5bbcf54abeeae400b33f618407a0c99f0</id>
<content type='text'>
All architectures now support HAVE_SYSCALL_TABLE_SUPPORT, so the flag is
no longer needed. With the removal of the flag, the related
GENERIC_SYSCALL_TABLE can also be removed.

libaudit was only used as a fallback for when HAVE_SYSCALL_TABLE_SUPPORT
was not defined, so libaudit is also no longer needed for any
architecture.

Signed-off-by: Charlie Jenkins &lt;charlie@rivosinc.com&gt;
Tested-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Christian Brauner &lt;brauner@kernel.org&gt;
Cc: Guo Ren &lt;guoren@kernel.org&gt;
Cc: Günther Noack &lt;gnoack@google.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: James Clark &lt;james.clark@linaro.org&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: John Garry &lt;john.g.garry@oracle.com&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: Leo Yan &lt;leo.yan@linux.dev&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Mickaël Salaün &lt;mic@digikod.net&gt;
Cc: Mike Leach &lt;mike.leach@linaro.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Palmer Dabbelt &lt;palmer@dabbelt.com&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Link: https://lore.kernel.org/r/20250108-perf_syscalltbl-v6-16-7543b5293098@rivosinc.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>
All architectures now support HAVE_SYSCALL_TABLE_SUPPORT, so the flag is
no longer needed. With the removal of the flag, the related
GENERIC_SYSCALL_TABLE can also be removed.

libaudit was only used as a fallback for when HAVE_SYSCALL_TABLE_SUPPORT
was not defined, so libaudit is also no longer needed for any
architecture.

Signed-off-by: Charlie Jenkins &lt;charlie@rivosinc.com&gt;
Tested-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Christian Brauner &lt;brauner@kernel.org&gt;
Cc: Guo Ren &lt;guoren@kernel.org&gt;
Cc: Günther Noack &lt;gnoack@google.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: James Clark &lt;james.clark@linaro.org&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: John Garry &lt;john.g.garry@oracle.com&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: Leo Yan &lt;leo.yan@linux.dev&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Mickaël Salaün &lt;mic@digikod.net&gt;
Cc: Mike Leach &lt;mike.leach@linaro.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Palmer Dabbelt &lt;palmer@dabbelt.com&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Link: https://lore.kernel.org/r/20250108-perf_syscalltbl-v6-16-7543b5293098@rivosinc.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf tools s390: Use generic syscall table scripts</title>
<updated>2025-01-10T13:59:42+00:00</updated>
<author>
<name>Charlie Jenkins</name>
<email>charlie@rivosinc.com</email>
</author>
<published>2025-01-09T02:36:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=00d1bfae1b9618c4986c1d175d916011ed084fa4'/>
<id>00d1bfae1b9618c4986c1d175d916011ed084fa4</id>
<content type='text'>
Use the generic scripts to generate headers from the syscall table
instead of the custom ones for s390.

Signed-off-by: Charlie Jenkins &lt;charlie@rivosinc.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Christian Brauner &lt;brauner@kernel.org&gt;
Cc: Guo Ren &lt;guoren@kernel.org&gt;
Cc: Günther Noack &lt;gnoack@google.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: James Clark &lt;james.clark@linaro.org&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: John Garry &lt;john.g.garry@oracle.com&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: Leo Yan &lt;leo.yan@linux.dev&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Mickaël Salaün &lt;mic@digikod.net&gt;
Cc: Mike Leach &lt;mike.leach@linaro.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Palmer Dabbelt &lt;palmer@dabbelt.com&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Link: https://lore.kernel.org/r/20250108-perf_syscalltbl-v6-15-7543b5293098@rivosinc.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>
Use the generic scripts to generate headers from the syscall table
instead of the custom ones for s390.

Signed-off-by: Charlie Jenkins &lt;charlie@rivosinc.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Christian Brauner &lt;brauner@kernel.org&gt;
Cc: Guo Ren &lt;guoren@kernel.org&gt;
Cc: Günther Noack &lt;gnoack@google.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: James Clark &lt;james.clark@linaro.org&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: John Garry &lt;john.g.garry@oracle.com&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: Leo Yan &lt;leo.yan@linux.dev&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Mickaël Salaün &lt;mic@digikod.net&gt;
Cc: Mike Leach &lt;mike.leach@linaro.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Palmer Dabbelt &lt;palmer@dabbelt.com&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Link: https://lore.kernel.org/r/20250108-perf_syscalltbl-v6-15-7543b5293098@rivosinc.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf tools powerpc: Use generic syscall table scripts</title>
<updated>2025-01-10T13:57:01+00:00</updated>
<author>
<name>Charlie Jenkins</name>
<email>charlie@rivosinc.com</email>
</author>
<published>2025-01-09T02:36:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4c02c7e0a2194f2d0292746df2d2be1076b61cf9'/>
<id>4c02c7e0a2194f2d0292746df2d2be1076b61cf9</id>
<content type='text'>
Use the generic scripts to generate headers from the syscall table
instead of the custom ones for powerpc.

Signed-off-by: Charlie Jenkins &lt;charlie@rivosinc.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Christian Brauner &lt;brauner@kernel.org&gt;
Cc: Guo Ren &lt;guoren@kernel.org&gt;
Cc: Günther Noack &lt;gnoack@google.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: James Clark &lt;james.clark@linaro.org&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: John Garry &lt;john.g.garry@oracle.com&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: Leo Yan &lt;leo.yan@linux.dev&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Mickaël Salaün &lt;mic@digikod.net&gt;
Cc: Mike Leach &lt;mike.leach@linaro.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Palmer Dabbelt &lt;palmer@dabbelt.com&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Link: https://lore.kernel.org/r/20250108-perf_syscalltbl-v6-14-7543b5293098@rivosinc.com
Link: https://lore.kernel.org/lkml/20250110100505.78d81450@canb.auug.org.au
[ Stephen Rothwell noticed on linux-next that the powerpc build for perf was broken and ...]
Link: https://lore.kernel.org/lkml/20250109-perf_powerpc_spu-v1-1-c097fc43737e@rivosinc.com
[ ... Charlie fixed it up and asked for it to be squashed to avoid breaking bisection. ]
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>
Use the generic scripts to generate headers from the syscall table
instead of the custom ones for powerpc.

Signed-off-by: Charlie Jenkins &lt;charlie@rivosinc.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Christian Brauner &lt;brauner@kernel.org&gt;
Cc: Guo Ren &lt;guoren@kernel.org&gt;
Cc: Günther Noack &lt;gnoack@google.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: James Clark &lt;james.clark@linaro.org&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: John Garry &lt;john.g.garry@oracle.com&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: Leo Yan &lt;leo.yan@linux.dev&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Mickaël Salaün &lt;mic@digikod.net&gt;
Cc: Mike Leach &lt;mike.leach@linaro.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Palmer Dabbelt &lt;palmer@dabbelt.com&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Link: https://lore.kernel.org/r/20250108-perf_syscalltbl-v6-14-7543b5293098@rivosinc.com
Link: https://lore.kernel.org/lkml/20250110100505.78d81450@canb.auug.org.au
[ Stephen Rothwell noticed on linux-next that the powerpc build for perf was broken and ...]
Link: https://lore.kernel.org/lkml/20250109-perf_powerpc_spu-v1-1-c097fc43737e@rivosinc.com
[ ... Charlie fixed it up and asked for it to be squashed to avoid breaking bisection. ]
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
