<feed xmlns='http://www.w3.org/2005/Atom'>
<title>talos-obmc-linux/tools/perf/tests, branch dev-4.13</title>
<subtitle>Talos™ II Linux sources for OpenBMC</subtitle>
<id>https://git.raptorcs.com/git/talos-obmc-linux/atom?h=dev-4.13</id>
<link rel='self' href='https://git.raptorcs.com/git/talos-obmc-linux/atom?h=dev-4.13'/>
<link rel='alternate' type='text/html' href='https://git.raptorcs.com/git/talos-obmc-linux/'/>
<updated>2017-06-27T14:49:13+00:00</updated>
<entry>
<title>perf tools: Kill die()</title>
<updated>2017-06-27T14:49:13+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2017-06-27T14:49:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.raptorcs.com/git/talos-obmc-linux/commit/?id=fef2a735167a827a65bbdf1791abe0dd070ce372'/>
<id>urn:sha1:fef2a735167a827a65bbdf1791abe0dd070ce372</id>
<content type='text'>
Finally can nuke this function, no more users.

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: http://lkml.kernel.org/n/tip-eivvvzn8ie6w42gy3batxoy7@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf tools: Remove warning()</title>
<updated>2017-06-27T14:13:20+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2017-06-27T14:13:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.raptorcs.com/git/talos-obmc-linux/commit/?id=b211d79ac1ad43d6d8d82e7f1a5c26055a249135'/>
<id>urn:sha1:b211d79ac1ad43d6d8d82e7f1a5c26055a249135</id>
<content type='text'>
Now everything uses pr_warning(), so ditch it.

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: http://lkml.kernel.org/n/tip-hv8r0mgdhk73wtfq3zrhavgx@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf tests: Add platform dependency to test 15</title>
<updated>2017-06-27T00:42:00+00:00</updated>
<author>
<name>Thomas Richter</name>
<email>tmricht@linux.vnet.ibm.com</email>
</author>
<published>2017-06-22T07:36:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.raptorcs.com/git/talos-obmc-linux/commit/?id=19508c048a2f90facb64624340bf1b7ee555442e'/>
<id>urn:sha1:19508c048a2f90facb64624340bf1b7ee555442e</id>
<content type='text'>
This patch adds platform dependency into the test case 15
(perf_event_attr). It is based on a suggestion from Jiri Olsa.

Add a new optional attribute named 'arch' in the [config] section of the
test case file. It is a comma separated list of architecture names this
test can be executed on. For example:

  arch = x86_64,alpha,ppc

If this attribute is missing the test is executed on any platform.  This
does not break existing behavior.

The values listed for this attribute should be identical to uname -m
output.

If the list starts with an exclamation mark (!) the comparison is
inverted, for example for

  arch = !s390x,ppc

the test is not executed on s390x or ppc platforms.  The exclamation
mark must be at the beginnning of the list.

Here is an example debug output:

  [root@s35lp76]# fgrep arch tests/attr/test-stat-C2
  arch = x86_64,alpha,ppc
  [root@s35lp76]# PERF_TEST_ATTR=/tmp /usr/bin/python2 ./tests/attr.py \
    -d ./tests/attr/ -p ./perf -vvvvv -t test-stat-C1

provides the following output:

  running './tests/attr//test-stat-C1'
  test limitation 'x86_64,alpha,ppc' &lt;--- new
    loading expected events
      Event event:base-stat
        fd = 1
        group_fd = -1
        .....

Here is the output when a test is skipped:

  [root@s35lp76]# fgrep arch tests/attr/test-stat-C1
  arch = !s390x
  [root@s35lp76]# PERF_TEST_ATTR=/tmp /usr/bin/python2 ./tests/attr.py \
    -d ./tests/attr/ -p ./perf -vvvvv -t test-stat-C1

provides the following output:

test limitation '!s390x' &lt;--- new

skipped [s390x] './tests/attr//test-stat-C1' &lt;--- new

The test is skipped with return code 0.

Suggested-and-Acked-by: Jiri Olsa &lt;jolsa@redhat.com&gt;
Reviewed-by: Arnaldo Carvalho de Melo &lt;acme@kernel.org&gt;
Signed-off-by: Thomas Richter &lt;tmricht@linux.vnet.ibm.com&gt;
Cc: Hendrik Brueckner &lt;brueckner@linux.vnet.ibm.com&gt;
Cc: linux-s390@vger.kernel.org
Link: http://lkml.kernel.org/r/20170622073625.86762-1-tmricht@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf test llvm: Avoid error when PROFILE_ALL_BRANCHES is set</title>
<updated>2017-06-19T19:11:26+00:00</updated>
<author>
<name>Wang Nan</name>
<email>wangnan0@huawei.com</email>
</author>
<published>2017-06-20T18:32:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.raptorcs.com/git/talos-obmc-linux/commit/?id=9b57fb7e35957c6838f89f4ed7e3f8433a4bbfc5'/>
<id>urn:sha1:9b57fb7e35957c6838f89f4ed7e3f8433a4bbfc5</id>
<content type='text'>
The 'if' keyword is a define that expands to complex code when
CONFIG_PROFILE_ALL_BRANCHES is selected, which causes a 'perf test LLVM'
failure like:

  $ ./perf test LLVM
  35: LLVM search and compile                    :
  35.1: Basic BPF llvm compile                    : Ok
  35.2: kbuild searching                          : Ok
  35.3: Compile source for BPF prologue generation: FAILED!
  35.4: Compile source for BPF relocation         : Skip

The only affected test case is bpf-script-test-prologue.c
because it uses kernel headers and has 'if' inside.

This patch undefines 'if' to make it passes perf test.

More detailed analysis from a message in this thread, also by Wang:

The problem is caused by following relocation information:

  $ readelf -a ./llvmsubtest3
  ...
     [ 5] _ftrace_branch    PROGBITS         0000000000000000  00000260
          00000000000000a0  0000000000000000  WA       0     0     4
  ...
  Relocation section '.relfunc=null_lseek file-&gt;f_mode offset orig' at
  offset 0x490 contains 4 entries:
     Offset          Info           Type           Sym. Value    Sym. Name
  000000000038  000b00000001 unrecognized: 1       0000000000000000 _ftrace_branch
  0000000000b0  000b00000001 unrecognized: 1       0000000000000000 _ftrace_branch
  000000000128  000b00000001 unrecognized: 1       0000000000000000 _ftrace_branch
  0000000001c0  000b00000001 unrecognized: 1       0000000000000000 _ftrace_branch

  Relocation section '.rel_ftrace_branch' at offset 0x4d0 contains 8 entries:
     Offset          Info           Type           Sym. Value    Sym. Name
  000000000000  000200000001 unrecognized: 1       0000000000000000 .L__func__.bpf_func__n
  000000000008  000100000001 unrecognized: 1       0000000000000015 .L.str
  000000000028  000200000001 unrecognized: 1       0000000000000000 .L__func__.bpf_func__n
  000000000030  000100000001 unrecognized: 1       0000000000000015 .L.str
  000000000050  000200000001 unrecognized: 1       0000000000000000 .L__func__.bpf_func__n
  000000000058  000100000001 unrecognized: 1       0000000000000015 .L.str
  000000000078  000200000001 unrecognized: 1       0000000000000000 .L__func__.bpf_func__n
  000000000080  000100000001 unrecognized: 1       0000000000000015 .L.str
  ...

So I think the failure is because you enabled CONFIG_PROFILE_ALL_BRANCHES.

I can reproduce your buggy result by selecting
CONFIG_PROFILE_ALL_BRANCHES in my kbuild:

  $ ./perf test LLVM
  35: LLVM search and compile                    :
  35.1: Basic BPF llvm compile                    : Ok
  35.2: kbuild searching                          : Ok
  35.3: Compile source for BPF prologue generation: FAILED!
  35.4: Compile source for BPF relocation         : Skip

Simply undef CONFIG_PROFILE_ALL_BRANCHES in clang opts not working
because it is introduced by "#include &lt;uapi/linux/fs.h&gt;", which override
cmdline options. So I think the best way is to undefine 'if' inside BPF
script.

Reported-and-Tested-by: Thomas-Mich Richter &lt;tmricht@linux.vnet.ibm.com&gt;
Signed-off-by: Wang Nan &lt;wangnan0@huawei.com&gt;
Cc: Alexei Starovoitov &lt;alexei.starovoitov@gmail.com&gt;
Cc: Hendrik Brueckner &lt;brueckner@linux.vnet.ibm.com&gt;
Cc: Zefan Li &lt;lizefan@huawei.com&gt;
Link: http://lkml.kernel.org/r/20170620183203.2517-1-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>tools: Adopt noinline from kernel sources</title>
<updated>2017-06-19T18:27:06+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2017-06-16T14:39:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.raptorcs.com/git/talos-obmc-linux/commit/?id=9dd4ca470e03334f95cc96529ba090921aac8eab'/>
<id>urn:sha1:9dd4ca470e03334f95cc96529ba090921aac8eab</id>
<content type='text'>
To have a more compact way to ask the compiler not to inline a function
and to make tools/ source code look like kernel code.

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: http://lkml.kernel.org/n/tip-bis4pqxegt6gbm5dlqs937tn@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf tools: Fix build with ARCH=x86_64</title>
<updated>2017-06-14T18:44:29+00:00</updated>
<author>
<name>Jiada Wang</name>
<email>jiada_wang@mentor.com</email>
</author>
<published>2017-04-10T03:02:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.raptorcs.com/git/talos-obmc-linux/commit/?id=7a759cd8e8272ee18922838ee711219c7c796a31'/>
<id>urn:sha1:7a759cd8e8272ee18922838ee711219c7c796a31</id>
<content type='text'>
With commit: 0a943cb10ce78 (tools build: Add HOSTARCH Makefile variable)
when building for ARCH=x86_64, ARCH=x86_64 is passed to perf instead of
ARCH=x86, so the perf build process searchs header files from
tools/arch/x86_64/include, which doesn't exist.

The following build failure is seen:

  In file included from util/event.c:2:0:
    tools/include/uapi/linux/mman.h:4:27: fatal error: uapi/asm/mman.h: No such file or directory
    compilation terminated.

Fix this issue by using SRCARCH instead of ARCH in perf, just like the
main kernel Makefile and tools/objtool's.

Signed-off-by: Jiada Wang &lt;jiada_wang@mentor.com&gt;
Tested-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Eugeniu Rosca &lt;erosca@de.adit-jv.com&gt;
Cc: Jan Stancek &lt;jstancek@redhat.com&gt;
Cc: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Ravi Bangoria &lt;ravi.bangoria@linux.vnet.ibm.com&gt;
Cc: Rui Teng &lt;rui.teng@linux.vnet.ibm.com&gt;
Cc: Sukadev Bhattiprolu &lt;sukadev@linux.vnet.ibm.com&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Fixes: 0a943cb10ce7 ("tools build: Add HOSTARCH Makefile variable")
Link: http://lkml.kernel.org/r/1491793357-14977-2-git-send-email-jiada_wang@mentor.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf evsel: Fix probing of precise_ip level for default cycles event</title>
<updated>2017-06-14T18:44:29+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2017-06-09T19:54:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.raptorcs.com/git/talos-obmc-linux/commit/?id=7a1ac110c22eb726684c837544a2d42c33e07be7'/>
<id>urn:sha1:7a1ac110c22eb726684c837544a2d42c33e07be7</id>
<content type='text'>
Since commit 18e7a45af91a ("perf/x86: Reject non sampling events with
precise_ip") returns -EINVAL for sys_perf_event_open() with an attribute
with (attr.precise_ip &gt; 0 &amp;&amp; attr.sample_period == 0), just like is done
in the routine used to probe the max precise level when no events were
passed to 'perf record' or 'perf top', i.e.:

	perf_evsel__new_cycles()
		perf_event_attr__set_max_precise_ip()

The x86 code, in x86_pmu_hw_config(), which is called all the way from
sys_perf_event_open() did, starting with the aforementioned commit:

                /* There's no sense in having PEBS for non sampling events: */
                if (!is_sampling_event(event))
                        return -EINVAL;

Which makes it fail for cycles:ppp, cycles:pp and cycles:p, always using
just the non precise cycles variant.

To make sure that this is the case, I tested it, before this patch,
with:

  # perf probe -L x86_pmu_hw_config
  &lt;x86_pmu_hw_config@/home/acme/git/linux/arch/x86/events/core.c:0&gt;
        0  int x86_pmu_hw_config(struct perf_event *event)
        1  {
        2         if (event-&gt;attr.precise_ip) {
&lt;SNIP&gt;
       17                 if (event-&gt;attr.precise_ip &gt; precise)
       18                         return -EOPNOTSUPP;

                          /* There's no sense in having PEBS for non sampling events: */
       21                 if (!is_sampling_event(event))
       22                         return -EINVAL;
                  }
&lt;SNIP&gt;
  # perf probe x86_pmu_hw_config:22
  Added new events:
    probe:x86_pmu_hw_config (on x86_pmu_hw_config:22)
    probe:x86_pmu_hw_config_1 (on x86_pmu_hw_config:22)

  You can now use it in all perf tools, such as:

        perf record -e probe:x86_pmu_hw_config_1 -aR sleep 1

  # perf trace -e perf_event_open,probe:x86_pmu_hwconfig*/max-stack=16/ perf record usleep 1
     0.000 ( 0.015 ms): perf/4150 perf_event_open(attr_uptr: 0x7ffebc8ba110, cpu: -1, group_fd: -1      ) ...
     0.015 (         ): probe:x86_pmu_hw_config:(ffffffff9c0065e1))
                                       x86_pmu_hw_config ([kernel.kallsyms])
                                       hsw_hw_config ([kernel.kallsyms])
                                       x86_pmu_event_init ([kernel.kallsyms])
                                       perf_try_init_event ([kernel.kallsyms])
                                       perf_event_alloc ([kernel.kallsyms])
                                       SYSC_perf_event_open ([kernel.kallsyms])
                                       sys_perf_event_open ([kernel.kallsyms])
                                       do_syscall_64 ([kernel.kallsyms])
                                       return_from_SYSCALL_64 ([kernel.kallsyms])
                                       syscall (/usr/lib64/libc-2.24.so)
                                       perf_event_attr__set_max_precise_ip (/home/acme/bin/perf)
                                       perf_evsel__new_cycles (/home/acme/bin/perf)
                                       perf_evlist__add_default (/home/acme/bin/perf)
                                       cmd_record (/home/acme/bin/perf)
                                       run_builtin (/home/acme/bin/perf)
                                       handle_internal_command (/home/acme/bin/perf)
     0.000 ( 0.021 ms): perf/4150  ... [continued]: perf_event_open()) = -1 EINVAL Invalid argument
     0.023 ( 0.002 ms): perf/4150 perf_event_open(attr_uptr: 0x7ffebc8ba110, cpu: -1, group_fd: -1      ) ...
     0.025 (         ): probe:x86_pmu_hw_config:(ffffffff9c0065e1))
                                       x86_pmu_hw_config ([kernel.kallsyms])
                                       hsw_hw_config ([kernel.kallsyms])
                                       x86_pmu_event_init ([kernel.kallsyms])
                                       perf_try_init_event ([kernel.kallsyms])
                                       perf_event_alloc ([kernel.kallsyms])
                                       SYSC_perf_event_open ([kernel.kallsyms])
                                       sys_perf_event_open ([kernel.kallsyms])
                                       do_syscall_64 ([kernel.kallsyms])
                                       return_from_SYSCALL_64 ([kernel.kallsyms])
                                       syscall (/usr/lib64/libc-2.24.so)
                                       perf_event_attr__set_max_precise_ip (/home/acme/bin/perf)
                                       perf_evsel__new_cycles (/home/acme/bin/perf)
                                       perf_evlist__add_default (/home/acme/bin/perf)
                                       cmd_record (/home/acme/bin/perf)
                                       run_builtin (/home/acme/bin/perf)
                                       handle_internal_command (/home/acme/bin/perf)
     0.023 ( 0.004 ms): perf/4150  ... [continued]: perf_event_open()) = -1 EINVAL Invalid argument
     0.028 ( 0.002 ms): perf/4150 perf_event_open(attr_uptr: 0x7ffebc8ba110, cpu: -1, group_fd: -1      ) ...
     0.030 (         ): probe:x86_pmu_hw_config:(ffffffff9c0065e1))
                                       x86_pmu_hw_config ([kernel.kallsyms])
                                       hsw_hw_config ([kernel.kallsyms])
                                       x86_pmu_event_init ([kernel.kallsyms])
                                       perf_try_init_event ([kernel.kallsyms])
                                       perf_event_alloc ([kernel.kallsyms])
                                       SYSC_perf_event_open ([kernel.kallsyms])
                                       sys_perf_event_open ([kernel.kallsyms])
                                       do_syscall_64 ([kernel.kallsyms])
                                       return_from_SYSCALL_64 ([kernel.kallsyms])
                                       syscall (/usr/lib64/libc-2.24.so)
                                       perf_event_attr__set_max_precise_ip (/home/acme/bin/perf)
                                       perf_evsel__new_cycles (/home/acme/bin/perf)
                                       perf_evlist__add_default (/home/acme/bin/perf)
                                       cmd_record (/home/acme/bin/perf)
                                       run_builtin (/home/acme/bin/perf)
                                       handle_internal_command (/home/acme/bin/perf)
     0.028 ( 0.004 ms): perf/4150  ... [continued]: perf_event_open()) = -1 EINVAL Invalid argument
    41.018 ( 0.012 ms): perf/4150 perf_event_open(attr_uptr: 0x7ffebc8b5dd0, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 4
    41.065 ( 0.011 ms): perf/4150 perf_event_open(attr_uptr: 0x3c7db78, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 4
    41.080 ( 0.006 ms): perf/4150 perf_event_open(attr_uptr: 0x3c7db78, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 4
    41.103 ( 0.010 ms): perf/4150 perf_event_open(attr_uptr: 0x3c4e748, pid: 4151 (perf), group_fd: -1, flags: FD_CLOEXEC) = 4
    41.115 ( 0.006 ms): perf/4150 perf_event_open(attr_uptr: 0x3c4e748, pid: 4151 (perf), cpu: 1, group_fd: -1, flags: FD_CLOEXEC) = 5
    41.122 ( 0.004 ms): perf/4150 perf_event_open(attr_uptr: 0x3c4e748, pid: 4151 (perf), cpu: 2, group_fd: -1, flags: FD_CLOEXEC) = 6
    41.128 ( 0.008 ms): perf/4150 perf_event_open(attr_uptr: 0x3c4e748, pid: 4151 (perf), cpu: 3, group_fd: -1, flags: FD_CLOEXEC) = 8
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.017 MB perf.data (2 samples) ]
  #

I.e. that return -EINVAL in x86_pmu_hw_config() is hit three times.

So fix it by just setting attr.sample_period

Now, after this patch:

  # perf trace --max-stack=2 -e perf_event_open,probe:x86_pmu_hw_config* perf record usleep 1
  [ perf record: Woken up 1 times to write data ]
     0.000 ( 0.017 ms): perf/8469 perf_event_open(attr_uptr: 0x7ffe36c27d10, pid: -1, cpu: 3, group_fd: -1, flags: FD_CLOEXEC) = 4
                                       syscall (/usr/lib64/libc-2.24.so)
                                       perf_event_open_cloexec_flag (/home/acme/bin/perf)
     0.050 ( 0.031 ms): perf/8469 perf_event_open(attr_uptr: 0x24ebb78, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 4
                                       syscall (/usr/lib64/libc-2.24.so)
                                       perf_evlist__config (/home/acme/bin/perf)
     0.092 ( 0.040 ms): perf/8469 perf_event_open(attr_uptr: 0x24ebb78, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 4
                                       syscall (/usr/lib64/libc-2.24.so)
                                       perf_evlist__config (/home/acme/bin/perf)
     0.143 ( 0.007 ms): perf/8469 perf_event_open(attr_uptr: 0x24bc748, cpu: -1, group_fd: -1           ) = 4
                                       syscall (/usr/lib64/libc-2.24.so)
                                       perf_event_attr__set_max_precise_ip (/home/acme/bin/perf)
     0.161 ( 0.007 ms): perf/8469 perf_event_open(attr_uptr: 0x24bc748, pid: 8470 (perf), group_fd: -1, flags: FD_CLOEXEC) = 4
                                       syscall (/usr/lib64/libc-2.24.so)
                                       perf_evsel__open (/home/acme/bin/perf)
     0.171 ( 0.005 ms): perf/8469 perf_event_open(attr_uptr: 0x24bc748, pid: 8470 (perf), cpu: 1, group_fd: -1, flags: FD_CLOEXEC) = 5
                                       syscall (/usr/lib64/libc-2.24.so)
                                       perf_evsel__open (/home/acme/bin/perf)
     0.180 ( 0.007 ms): perf/8469 perf_event_open(attr_uptr: 0x24bc748, pid: 8470 (perf), cpu: 2, group_fd: -1, flags: FD_CLOEXEC) = 6
                                       syscall (/usr/lib64/libc-2.24.so)
                                       perf_evsel__open (/home/acme/bin/perf)
     0.190 ( 0.005 ms): perf/8469 perf_event_open(attr_uptr: 0x24bc748, pid: 8470 (perf), cpu: 3, group_fd: -1, flags: FD_CLOEXEC) = 8
                                       syscall (/usr/lib64/libc-2.24.so)
                                       perf_evsel__open (/home/acme/bin/perf)
  [ perf record: Captured and wrote 0.017 MB perf.data (7 samples) ]
  #

The probe one called from perf_event_attr__set_max_precise_ip() works
the first time, with attr.precise_ip = 3, wit hthe next ones being the
per cpu ones for the cycles:ppp event.

And here is the text from a report and alternative proposed patch by
Thomas-Mich Richter:

 ---

On s390 the counter and sampling facility do not support a precise IP
skid level and sometimes returns EOPNOTSUPP when structure member
precise_ip in struct perf_event_attr is not set to zero.

On s390 commnd 'perf record -- true' fails with error EOPNOTSUPP.  This
happens only when no events are specified on command line.

The functions called are
...
  --&gt; perf_evlist__add_default
      --&gt; perf_evsel__new_cycles
          --&gt; perf_event_attr__set_max_precise_ip

The last function determines the value of structure member precise_ip by
invoking the perf_event_open() system call and checking the return code.
The first successful open is the value for precise_ip.

However the value is determined without setting member sample_period and
indicates no sampling.

On s390 the counter facility and sampling facility are different.  The
above procedure determines a precise_ip value of 3 using the counter
facility. Later it uses the sampling facility with a value of 3 and
fails with EOPNOTSUPP.

 ---

v2: Older compilers (e.g. gcc 4.4.7) don't support referencing members
    of unnamed union members in the container struct initialization, so
    move from:

	struct perf_event_attr attr = {
		...
		.sample_period = 1,
	};

to right after it as:

	struct perf_event_attr attr = {
		...
	};

	attr.sample_period = 1;

v3: We need to reset .sample_period to 0 to let the users of
perf_evsel__new_cycles() to properly setup attr.sample_period or
attr.sample_freq. Reported by Ingo Molnar.

Reported-and-Acked-by: Thomas-Mich Richter &lt;tmricht@linux.vnet.ibm.com&gt;
Acked-by: Hendrik Brueckner &lt;brueckner@linux.vnet.ibm.com&gt;
Acked-by: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Fixes: 18e7a45af91a ("perf/x86: Reject non sampling events with precise_ip")
Link: http://lkml.kernel.org/n/tip-yv6nnkl7tzqocrm0hl3x7vf1@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf tests: Decompress kernel module before objdump</title>
<updated>2017-06-08T18:39:19+00:00</updated>
<author>
<name>Namhyung Kim</name>
<email>namhyung@kernel.org</email>
</author>
<published>2017-06-08T07:31:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.raptorcs.com/git/talos-obmc-linux/commit/?id=94df1040b1e6aacd8dec0ba3c61d7e77cd695f26'/>
<id>urn:sha1:94df1040b1e6aacd8dec0ba3c61d7e77cd695f26</id>
<content type='text'>
If a kernel modules is compressed, it should be decompressed before
running objdump to parse binary data correctly.  This fixes a failure of
object code reading test for me.

Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Acked-by: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170608073109.30699-8-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf test: Disable breakpoint signal tests for powerpc</title>
<updated>2017-06-05T17:18:01+00:00</updated>
<author>
<name>Jiri Olsa</name>
<email>jolsa@redhat.com</email>
</author>
<published>2017-06-01T20:54:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.raptorcs.com/git/talos-obmc-linux/commit/?id=598762cf91532e6e86dd21199b5e7f803df73f49'/>
<id>urn:sha1:598762cf91532e6e86dd21199b5e7f803df73f49</id>
<content type='text'>
The following tests are failing on powerpc:

  # perf test break
  18: Breakpoint overflow signal handler  : FAILED!
  19: Breakpoint overflow sampling        : FAILED!

The powerpc kenel so far does not have support to even create
instruction breakpoints using the perf event interface, so those tests
fail early in the config phase.

I added a '-&gt;is_supported()' callback to test struct to be able to
disable specific tests. It seems better than putting ifdefs directly to
the test array.

Signed-off-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/20170601205450.GA398@krava
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf tests kmod-path: Don't fail if compressed modules aren't supported</title>
<updated>2017-05-04T13:05:55+00:00</updated>
<author>
<name>Kim Phillips</name>
<email>kim.phillips@arm.com</email>
</author>
<published>2017-05-03T12:14:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.raptorcs.com/git/talos-obmc-linux/commit/?id=805b151a1afd24414706a7f6ae275fbb9649be74'/>
<id>urn:sha1:805b151a1afd24414706a7f6ae275fbb9649be74</id>
<content type='text'>
__kmod_path__parse() uses is_supported_compression() to determine and
parse out compressed module file extensions.  On systems without zlib,
this test fails and __kmod_path__parse() continues to strcmp "ko" with
"gz".  Don't do this on those systems.

Signed-off-by: Kim Phillips &lt;kim.phillips@arm.com&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Fixes: 3c8a67f50a1e ("perf tools: Add kmod_path__parse function")
Link: http://lkml.kernel.org/r/20170503131402.c66e314460026c80cd787b34@arm.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
</feed>
