<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/tools/perf, branch v3.18.129</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>perf tools: Cleanup trace-event-info 'tdata' leak</title>
<updated>2018-11-22T06:32:42+00:00</updated>
<author>
<name>Sanskriti Sharma</name>
<email>sansharm@redhat.com</email>
</author>
<published>2018-10-02T14:29:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=dac6480460793316bc9cd911ce2ff1250a5a1acb'/>
<id>dac6480460793316bc9cd911ce2ff1250a5a1acb</id>
<content type='text'>
[ Upstream commit faedbf3fd19f2511a39397f76359e4cc6ee93072 ]

Free tracing_data structure in tracing_data_get() error paths.

Fixes the following coverity complaint:

  Error: RESOURCE_LEAK (CWE-772):
  leaked_storage: Variable "tdata" going out of scope leaks the storage

Signed-off-by: Sanskriti Sharma &lt;sansharm@redhat.com&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Joe Lawrence &lt;joe.lawrence@redhat.com&gt;
Link: http://lkml.kernel.org/r/1538490554-8161-3-git-send-email-sansharm@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit faedbf3fd19f2511a39397f76359e4cc6ee93072 ]

Free tracing_data structure in tracing_data_get() error paths.

Fixes the following coverity complaint:

  Error: RESOURCE_LEAK (CWE-772):
  leaked_storage: Variable "tdata" going out of scope leaks the storage

Signed-off-by: Sanskriti Sharma &lt;sansharm@redhat.com&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Joe Lawrence &lt;joe.lawrence@redhat.com&gt;
Link: http://lkml.kernel.org/r/1538490554-8161-3-git-send-email-sansharm@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf tools: Free temporary 'sys' string in read_event_files()</title>
<updated>2018-11-22T06:32:42+00:00</updated>
<author>
<name>Sanskriti Sharma</name>
<email>sansharm@redhat.com</email>
</author>
<published>2018-10-02T14:29:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3f237bd15d2e71348a9f5c34a987a8424b8c6c39'/>
<id>3f237bd15d2e71348a9f5c34a987a8424b8c6c39</id>
<content type='text'>
[ Upstream commit 1e44224fb0528b4c0cc176bde2bb31e9127eb14b ]

For each system in a given pevent, read_event_files() reads in a
temporary 'sys' string.  Be sure to free this string before moving onto
to the next system and/or leaving read_event_files().

Fixes the following coverity complaints:

  Error: RESOURCE_LEAK (CWE-772):

  tools/perf/util/trace-event-read.c:343: overwrite_var: Overwriting
  "sys" in "sys = read_string()" leaks the storage that "sys" points to.

  tools/perf/util/trace-event-read.c:353: leaked_storage: Variable "sys"
  going out of scope leaks the storage it points to.

Signed-off-by: Sanskriti Sharma &lt;sansharm@redhat.com&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Joe Lawrence &lt;joe.lawrence@redhat.com&gt;
Link: http://lkml.kernel.org/r/1538490554-8161-6-git-send-email-sansharm@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 1e44224fb0528b4c0cc176bde2bb31e9127eb14b ]

For each system in a given pevent, read_event_files() reads in a
temporary 'sys' string.  Be sure to free this string before moving onto
to the next system and/or leaving read_event_files().

Fixes the following coverity complaints:

  Error: RESOURCE_LEAK (CWE-772):

  tools/perf/util/trace-event-read.c:343: overwrite_var: Overwriting
  "sys" in "sys = read_string()" leaks the storage that "sys" points to.

  tools/perf/util/trace-event-read.c:353: leaked_storage: Variable "sys"
  going out of scope leaks the storage it points to.

Signed-off-by: Sanskriti Sharma &lt;sansharm@redhat.com&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Joe Lawrence &lt;joe.lawrence@redhat.com&gt;
Link: http://lkml.kernel.org/r/1538490554-8161-6-git-send-email-sansharm@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf tools: Disable parallelism for 'make clean'</title>
<updated>2018-11-10T15:39:21+00:00</updated>
<author>
<name>Rasmus Villemoes</name>
<email>linux@rasmusvillemoes.dk</email>
</author>
<published>2018-07-05T13:15:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=df10e01a5624c972a05d3a29e4d0ba0500f04f62'/>
<id>df10e01a5624c972a05d3a29e4d0ba0500f04f62</id>
<content type='text'>
[ Upstream commit da15fc2fa9c07b23db8f5e479bd8a9f0d741ca07 ]

The Yocto build system does a 'make clean' when rebuilding due to
changed dependencies, and that consistently fails for me (causing the
whole BSP build to fail) with errors such as

| find: '[...]/perf/1.0-r9/perf-1.0/plugin_mac80211.so': No such file or directory
| find: '[...]/perf/1.0-r9/perf-1.0/plugin_mac80211.so': No such file or directory
| find: find: '[...]/perf/1.0-r9/perf-1.0/libtraceevent.a''[...]/perf/1.0-r9/perf-1.0/libtraceevent.a': No such file or directory: No such file or directory
|
[...]
| find: cannot delete '/mnt/xfs/devel/pil/yocto/tmp-glibc/work/wandboard-oe-linux-gnueabi/perf/1.0-r9/perf-1.0/util/.pstack.o.cmd': No such file or directory

Apparently (despite the comment), 'make clean' ends up launching
multiple sub-makes that all want to remove the same things - perhaps
this only happens in combination with a O=... parameter. In any case, we
don't lose much by explicitly disabling the parallelism for the clean
target, and it makes automated builds much more reliable.

Signed-off-by: Rasmus Villemoes &lt;linux@rasmusvillemoes.dk&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lkml.kernel.org/r/20180705131527.19749-1-linux@rasmusvillemoes.dk
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 da15fc2fa9c07b23db8f5e479bd8a9f0d741ca07 ]

The Yocto build system does a 'make clean' when rebuilding due to
changed dependencies, and that consistently fails for me (causing the
whole BSP build to fail) with errors such as

| find: '[...]/perf/1.0-r9/perf-1.0/plugin_mac80211.so': No such file or directory
| find: '[...]/perf/1.0-r9/perf-1.0/plugin_mac80211.so': No such file or directory
| find: find: '[...]/perf/1.0-r9/perf-1.0/libtraceevent.a''[...]/perf/1.0-r9/perf-1.0/libtraceevent.a': No such file or directory: No such file or directory
|
[...]
| find: cannot delete '/mnt/xfs/devel/pil/yocto/tmp-glibc/work/wandboard-oe-linux-gnueabi/perf/1.0-r9/perf-1.0/util/.pstack.o.cmd': No such file or directory

Apparently (despite the comment), 'make clean' ends up launching
multiple sub-makes that all want to remove the same things - perhaps
this only happens in combination with a O=... parameter. In any case, we
don't lose much by explicitly disabling the parallelism for the clean
target, and it makes automated builds much more reliable.

Signed-off-by: Rasmus Villemoes &lt;linux@rasmusvillemoes.dk&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lkml.kernel.org/r/20180705131527.19749-1-linux@rasmusvillemoes.dk
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 bench numa: Fix to show proper convergence stats</title>
<updated>2018-11-10T15:39:18+00:00</updated>
<author>
<name>Srikar Dronamraju</name>
<email>srikar@linux.vnet.ibm.com</email>
</author>
<published>2015-06-24T11:10:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7c852f4aa687dbc71567c06aa22e87f1122dd6d2'/>
<id>7c852f4aa687dbc71567c06aa22e87f1122dd6d2</id>
<content type='text'>
[ Upstream commit 2b42b09b88c831ba4da2d669581dde371c38c2af ]

With commit: e1e455f4f4d3 (perf tools: Work around lack of sched_getcpu
in glibc &lt; 2.6), perf_bench numa mem with -c or -m option is not able to
correctly calculate convergence.

With the above commit, sched_getcpu always seems to return -1. The
intention of commit e1e455f was to add a sched_getcpu in glibc &lt; 2.6.
Hence keep the sched_getcpu definition under an ifdef.

This regression happened occurred between v4.0 and v4.1

Signed-off-by: Srikar Dronamraju &lt;srikar@linux.vnet.ibm.com&gt;
Acked-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Masami Hiramatsu &lt;masami.hiramatsu.pt@hitachi.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Vinson Lee &lt;vlee@twitter.com&gt;
Fixes:  e1e455f4f4d3 ("perf tools: Work around lack of sched_getcpu in glibc &lt; 2.6")
Link: http://lkml.kernel.org/r/20150624111004.GA5220@linux.vnet.ibm.com
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 2b42b09b88c831ba4da2d669581dde371c38c2af ]

With commit: e1e455f4f4d3 (perf tools: Work around lack of sched_getcpu
in glibc &lt; 2.6), perf_bench numa mem with -c or -m option is not able to
correctly calculate convergence.

With the above commit, sched_getcpu always seems to return -1. The
intention of commit e1e455f was to add a sched_getcpu in glibc &lt; 2.6.
Hence keep the sched_getcpu definition under an ifdef.

This regression happened occurred between v4.0 and v4.1

Signed-off-by: Srikar Dronamraju &lt;srikar@linux.vnet.ibm.com&gt;
Acked-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Masami Hiramatsu &lt;masami.hiramatsu.pt@hitachi.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Vinson Lee &lt;vlee@twitter.com&gt;
Fixes:  e1e455f4f4d3 ("perf tools: Work around lack of sched_getcpu in glibc &lt; 2.6")
Link: http://lkml.kernel.org/r/20150624111004.GA5220@linux.vnet.ibm.com
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 tools: Fix segfault for symbol annotation on TUI</title>
<updated>2018-11-10T15:39:17+00:00</updated>
<author>
<name>Namhyung Kim</name>
<email>namhyung@kernel.org</email>
</author>
<published>2015-01-14T11:18:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=12c2155a4178686dd3b6783f074f4146956a2af2'/>
<id>12c2155a4178686dd3b6783f074f4146956a2af2</id>
<content type='text'>
[ Upstream commit 813ccd15452ed34e97aa526ffc70d6d8e6c466c5 ]

Currently the symbol structure is allocated with symbol_conf.priv_size
to carry sideband information like annotation, map browser on TUI and
sort-by-name tree node.  So retrieving these information from symbol
needs to care about the details of such placement.

However the annotation code just assumes that the symbol is placed after
the struct annotation.  But actually there's other info between them.
So accessing those struct will lead to an undefined behavior (usually a
crash) after they write their info to the same location.

To reproduce the problem, please follow the steps below:

  1. run perf report (TUI of course) with -v option
  2. open map browser (by pressing right arrow key for any entry)
  3. search any function (by pressing '/' key and input whatever..)
  4. return to the hist browser (by pressing 'q' or left arrow key)
  5. open annotation window for the same entry (by pressing 'a' key)

Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Masami Hiramatsu &lt;masami.hiramatsu.pt@hitachi.com&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/1421234288-22758-1-git-send-email-namhyung@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 813ccd15452ed34e97aa526ffc70d6d8e6c466c5 ]

Currently the symbol structure is allocated with symbol_conf.priv_size
to carry sideband information like annotation, map browser on TUI and
sort-by-name tree node.  So retrieving these information from symbol
needs to care about the details of such placement.

However the annotation code just assumes that the symbol is placed after
the struct annotation.  But actually there's other info between them.
So accessing those struct will lead to an undefined behavior (usually a
crash) after they write their info to the same location.

To reproduce the problem, please follow the steps below:

  1. run perf report (TUI of course) with -v option
  2. open map browser (by pressing right arrow key for any entry)
  3. search any function (by pressing '/' key and input whatever..)
  4. return to the hist browser (by pressing 'q' or left arrow key)
  5. open annotation window for the same entry (by pressing 'a' key)

Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Masami Hiramatsu &lt;masami.hiramatsu.pt@hitachi.com&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/1421234288-22758-1-git-send-email-namhyung@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 tools: Avoid build splat for syscall numbers with uclibc</title>
<updated>2018-11-10T15:39:17+00:00</updated>
<author>
<name>Vineet Gupta</name>
<email>Vineet.Gupta1@synopsys.com</email>
</author>
<published>2015-01-13T13:43:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0ebc7b86d70880ea4fe82c636353b8deaf3e7385'/>
<id>0ebc7b86d70880ea4fe82c636353b8deaf3e7385</id>
<content type='text'>
[ Upstream commit ea1fe3a88763d4dfef7e2529ba606f96e8e6b271 ]

This is due to duplicated unistd inclusion (via uClibc headers + kernel headers)
Also seen on ARM uClibc based tools

   ------- ARC build ----------&gt;8-------------

  CC       util/evlist.o
In file included from
~/arc/k.org/arch/arc/include/uapi/asm/unistd.h:25:0,
                 from util/../perf-sys.h:10,
                 from util/../perf.h:15,
                 from util/event.h:7,
                 from util/event.c:3:
~/arc/k.org/include/uapi/asm-generic/unistd.h:906:0:
warning: "__NR_fcntl64" redefined [enabled by default]
 #define __NR_fcntl64 __NR3264_fcntl
 ^
In file included from
~/arc/gnu/INSTALL_1412-arc-2014.12-rc1/arc-snps-linux-uclibc/sysroot/usr/include/sys/syscall.h:24:0,
                 from util/../perf-sys.h:6,
   -----------------&gt;8-------------------

   ------- ARM build ----------&gt;8-------------

  CC FPIC  plugin_scsi.o
In file included from util/../perf-sys.h:9:0,
                 from util/../perf.h:15,
                 from util/cache.h:7,
                 from perf.c:12:
~/arc/k.org/arch/arm/include/uapi/asm/unistd.h:28:0:
warning: "__NR_restart_syscall" redefined [enabled by default]
In file included from
~/buildroot/host/usr/arm-buildroot-linux-uclibcgnueabi/sysroot/usr/include/sys/syscall.h:25:0,
                 from util/../perf-sys.h:6,
                 from util/../perf.h:15,
                 from util/cache.h:7,
                 from perf.c:12:
~/buildroot/host/usr/arm-buildroot-linux-uclibcgnueabi/sysroot/usr/include/bits/sysnum.h:17:0:
note: this is the location of the previous definition
   -----------------&gt;8-------------------

Signed-off-by: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Cc: Alexey Brodkin &lt;Alexey.Brodkin@synopsys.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lkml.kernel.org/r/1421156604-30603-4-git-send-email-vgupta@synopsys.com
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 ea1fe3a88763d4dfef7e2529ba606f96e8e6b271 ]

This is due to duplicated unistd inclusion (via uClibc headers + kernel headers)
Also seen on ARM uClibc based tools

   ------- ARC build ----------&gt;8-------------

  CC       util/evlist.o
In file included from
~/arc/k.org/arch/arc/include/uapi/asm/unistd.h:25:0,
                 from util/../perf-sys.h:10,
                 from util/../perf.h:15,
                 from util/event.h:7,
                 from util/event.c:3:
~/arc/k.org/include/uapi/asm-generic/unistd.h:906:0:
warning: "__NR_fcntl64" redefined [enabled by default]
 #define __NR_fcntl64 __NR3264_fcntl
 ^
In file included from
~/arc/gnu/INSTALL_1412-arc-2014.12-rc1/arc-snps-linux-uclibc/sysroot/usr/include/sys/syscall.h:24:0,
                 from util/../perf-sys.h:6,
   -----------------&gt;8-------------------

   ------- ARM build ----------&gt;8-------------

  CC FPIC  plugin_scsi.o
In file included from util/../perf-sys.h:9:0,
                 from util/../perf.h:15,
                 from util/cache.h:7,
                 from perf.c:12:
~/arc/k.org/arch/arm/include/uapi/asm/unistd.h:28:0:
warning: "__NR_restart_syscall" redefined [enabled by default]
In file included from
~/buildroot/host/usr/arm-buildroot-linux-uclibcgnueabi/sysroot/usr/include/sys/syscall.h:25:0,
                 from util/../perf-sys.h:6,
                 from util/../perf.h:15,
                 from util/cache.h:7,
                 from perf.c:12:
~/buildroot/host/usr/arm-buildroot-linux-uclibcgnueabi/sysroot/usr/include/bits/sysnum.h:17:0:
note: this is the location of the previous definition
   -----------------&gt;8-------------------

Signed-off-by: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Cc: Alexey Brodkin &lt;Alexey.Brodkin@synopsys.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lkml.kernel.org/r/1421156604-30603-4-git-send-email-vgupta@synopsys.com
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 machine: Fix __machine__findnew_thread() error path</title>
<updated>2018-11-10T15:39:17+00:00</updated>
<author>
<name>Namhyung Kim</name>
<email>namhyung@kernel.org</email>
</author>
<published>2015-01-09T00:38:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=32eaad5795d2bcbc15d406b0f8c0f7a268aaafec'/>
<id>32eaad5795d2bcbc15d406b0f8c0f7a268aaafec</id>
<content type='text'>
[ Upstream commit 260d819e3abdbdaa2b88fb983d1314f1b263f9e2 ]

When thread__init_map_groups() fails, a new thread should be removed
from the rbtree since it's gonna be freed.  Also update last match cache
only if the function succeeded.

Reported-by: David Ahern &lt;dsahern@gmail.com&gt;
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/1420763892-15535-1-git-send-email-namhyung@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 260d819e3abdbdaa2b88fb983d1314f1b263f9e2 ]

When thread__init_map_groups() fails, a new thread should be removed
from the rbtree since it's gonna be freed.  Also update last match cache
only if the function succeeded.

Reported-by: David Ahern &lt;dsahern@gmail.com&gt;
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/1420763892-15535-1-git-send-email-namhyung@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 powerpc: Fix callchain ip filtering</title>
<updated>2018-09-26T06:33:56+00:00</updated>
<author>
<name>Sandipan Das</name>
<email>sandipan@linux.ibm.com</email>
</author>
<published>2018-07-10T13:58:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8eb6f3c1e90879b7407890acedebafce5e01ede1'/>
<id>8eb6f3c1e90879b7407890acedebafce5e01ede1</id>
<content type='text'>
[ Upstream commit c715fcfda5a08edabaa15508742be926b7ee51db ]

For powerpc64, redundant entries in the callchain are filtered out by
determining the state of the return address and the stack frame using
DWARF debug information.

For making these filtering decisions we must analyze the debug
information for the location corresponding to the program counter value,
i.e. the first entry in the callchain, and not the LR value; otherwise,
perf may filter out either the second or the third entry in the
callchain incorrectly.

This can be observed on a powerpc64le system running Fedora 27 as shown
below.

Case 1 - Attaching a probe at inet_pton+0x8 (binary offset 0x15af28).
         Return address is still in LR and a new stack frame is not yet
         allocated. The LR value, i.e. the second entry, should not be
	 filtered out.

  # objdump -d /usr/lib64/libc-2.26.so | less
  ...
  000000000010eb10 &lt;gaih_inet.constprop.7&gt;:
  ...
    10fa48:       78 bb e4 7e     mr      r4,r23
    10fa4c:       0a 00 60 38     li      r3,10
    10fa50:       d9 b4 04 48     bl      15af28 &lt;inet_pton+0x8&gt;
    10fa54:       00 00 00 60     nop
    10fa58:       ac f4 ff 4b     b       10ef04 &lt;gaih_inet.constprop.7+0x3f4&gt;
  ...
  0000000000110450 &lt;getaddrinfo&gt;:
  ...
    1105a8:       54 00 ff 38     addi    r7,r31,84
    1105ac:       58 00 df 38     addi    r6,r31,88
    1105b0:       69 e5 ff 4b     bl      10eb18 &lt;gaih_inet.constprop.7+0x8&gt;
    1105b4:       78 1b 71 7c     mr      r17,r3
    1105b8:       50 01 7f e8     ld      r3,336(r31)
  ...
  000000000015af20 &lt;inet_pton&gt;:
    15af20:       0b 00 4c 3c     addis   r2,r12,11
    15af24:       e0 c1 42 38     addi    r2,r2,-15904
    15af28:       a6 02 08 7c     mflr    r0
    15af2c:       f0 ff c1 fb     std     r30,-16(r1)
    15af30:       f8 ff e1 fb     std     r31,-8(r1)
  ...

  # perf probe -x /usr/lib64/libc-2.26.so -a inet_pton+0x8
  # perf record -e probe_libc:inet_pton -g ping -6 -c 1 ::1
  # perf script

Before:

  ping  4507 [002] 514985.546540: probe_libc:inet_pton: (7fffa7dbaf28)
              7fffa7dbaf28 __GI___inet_pton+0x8 (/usr/lib64/libc-2.26.so)
              7fffa7d705b4 getaddrinfo+0x164 (/usr/lib64/libc-2.26.so)
                 13fb52d70 _init+0xbfc (/usr/bin/ping)
              7fffa7c836a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc-2.26.so)
              7fffa7c83898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so)
                         0 [unknown] ([unknown])

After:

  ping  4507 [002] 514985.546540: probe_libc:inet_pton: (7fffa7dbaf28)
              7fffa7dbaf28 __GI___inet_pton+0x8 (/usr/lib64/libc-2.26.so)
              7fffa7d6fa54 gaih_inet.constprop.7+0xf44 (/usr/lib64/libc-2.26.so)
              7fffa7d705b4 getaddrinfo+0x164 (/usr/lib64/libc-2.26.so)
                 13fb52d70 _init+0xbfc (/usr/bin/ping)
              7fffa7c836a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc-2.26.so)
              7fffa7c83898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so)
                         0 [unknown] ([unknown])

Case 2 - Attaching a probe at _int_malloc+0x180 (binary offset 0x9cf10).
         Return address in still in LR and a new stack frame has already
         been allocated but not used. The caller's caller, i.e. the third
	 entry, is invalid and should be filtered out and not the second
	 one.

  # objdump -d /usr/lib64/libc-2.26.so | less
  ...
  000000000009cd90 &lt;_int_malloc&gt;:
     9cd90:       17 00 4c 3c     addis   r2,r12,23
     9cd94:       70 a3 42 38     addi    r2,r2,-23696
     9cd98:       26 00 80 7d     mfcr    r12
     9cd9c:       f8 ff e1 fb     std     r31,-8(r1)
     9cda0:       17 00 e4 3b     addi    r31,r4,23
     9cda4:       d8 ff 61 fb     std     r27,-40(r1)
     9cda8:       78 23 9b 7c     mr      r27,r4
     9cdac:       1f 00 bf 2b     cmpldi  cr7,r31,31
     9cdb0:       f0 ff c1 fb     std     r30,-16(r1)
     9cdb4:       b0 ff c1 fa     std     r22,-80(r1)
     9cdb8:       78 1b 7e 7c     mr      r30,r3
     9cdbc:       08 00 81 91     stw     r12,8(r1)
     9cdc0:       11 ff 21 f8     stdu    r1,-240(r1)
     9cdc4:       4c 01 9d 41     bgt     cr7,9cf10 &lt;_int_malloc+0x180&gt;
     9cdc8:       20 00 a4 2b     cmpldi  cr7,r4,32
  ...
     9cf08:       00 00 00 60     nop
     9cf0c:       00 00 42 60     ori     r2,r2,0
     9cf10:       e4 06 ff 7b     rldicr  r31,r31,0,59
     9cf14:       40 f8 a4 7f     cmpld   cr7,r4,r31
     9cf18:       68 05 9d 41     bgt     cr7,9d480 &lt;_int_malloc+0x6f0&gt;
  ...
  000000000009e3c0 &lt;tcache_init.part.4&gt;:
  ...
     9e420:       40 02 80 38     li      r4,576
     9e424:       78 fb e3 7f     mr      r3,r31
     9e428:       71 e9 ff 4b     bl      9cd98 &lt;_int_malloc+0x8&gt;
     9e42c:       00 00 a3 2f     cmpdi   cr7,r3,0
     9e430:       78 1b 7e 7c     mr      r30,r3
  ...
  000000000009f7a0 &lt;__libc_malloc&gt;:
  ...
     9f8f8:       00 00 89 2f     cmpwi   cr7,r9,0
     9f8fc:       1c ff 9e 40     bne     cr7,9f818 &lt;__libc_malloc+0x78&gt;
     9f900:       c9 ea ff 4b     bl      9e3c8 &lt;tcache_init.part.4+0x8&gt;
     9f904:       00 00 00 60     nop
     9f908:       e8 90 22 e9     ld      r9,-28440(r2)
  ...

  # perf probe -x /usr/lib64/libc-2.26.so -a _int_malloc+0x180
  # perf record -e probe_libc:_int_malloc -g ./test-malloc
  # perf script

Before:

  test-malloc  6554 [009] 515975.797403: probe_libc:_int_malloc: (7fffa6e6cf10)
              7fffa6e6cf10 _int_malloc+0x180 (/usr/lib64/libc-2.26.so)
              7fffa6dd0000 [unknown] (/usr/lib64/libc-2.26.so)
              7fffa6e6f904 malloc+0x164 (/usr/lib64/libc-2.26.so)
              7fffa6e6f9fc malloc+0x25c (/usr/lib64/libc-2.26.so)
                  100006b4 main+0x38 (/home/testuser/test-malloc)
              7fffa6df36a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc-2.26.so)
              7fffa6df3898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so)
                         0 [unknown] ([unknown])

After:

  test-malloc  6554 [009] 515975.797403: probe_libc:_int_malloc: (7fffa6e6cf10)
              7fffa6e6cf10 _int_malloc+0x180 (/usr/lib64/libc-2.26.so)
              7fffa6e6e42c tcache_init.part.4+0x6c (/usr/lib64/libc-2.26.so)
              7fffa6e6f904 malloc+0x164 (/usr/lib64/libc-2.26.so)
              7fffa6e6f9fc malloc+0x25c (/usr/lib64/libc-2.26.so)
                  100006b4 main+0x38 (/home/sandipan/test-malloc)
              7fffa6df36a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc-2.26.so)
              7fffa6df3898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so)
                         0 [unknown] ([unknown])

Signed-off-by: Sandipan Das &lt;sandipan@linux.ibm.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Maynard Johnson &lt;maynard@us.ibm.com&gt;
Cc: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Cc: Ravi Bangoria &lt;ravi.bangoria@linux.vnet.ibm.com&gt;
Cc: Sukadev Bhattiprolu &lt;sukadev@linux.vnet.ibm.com&gt;
Fixes: a60335ba3298 ("perf tools powerpc: Adjust callchain based on DWARF debug info")
Link: http://lkml.kernel.org/r/24bb726d91ed173aebc972ec3f41a2ef2249434e.1530724939.git.sandipan@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit c715fcfda5a08edabaa15508742be926b7ee51db ]

For powerpc64, redundant entries in the callchain are filtered out by
determining the state of the return address and the stack frame using
DWARF debug information.

For making these filtering decisions we must analyze the debug
information for the location corresponding to the program counter value,
i.e. the first entry in the callchain, and not the LR value; otherwise,
perf may filter out either the second or the third entry in the
callchain incorrectly.

This can be observed on a powerpc64le system running Fedora 27 as shown
below.

Case 1 - Attaching a probe at inet_pton+0x8 (binary offset 0x15af28).
         Return address is still in LR and a new stack frame is not yet
         allocated. The LR value, i.e. the second entry, should not be
	 filtered out.

  # objdump -d /usr/lib64/libc-2.26.so | less
  ...
  000000000010eb10 &lt;gaih_inet.constprop.7&gt;:
  ...
    10fa48:       78 bb e4 7e     mr      r4,r23
    10fa4c:       0a 00 60 38     li      r3,10
    10fa50:       d9 b4 04 48     bl      15af28 &lt;inet_pton+0x8&gt;
    10fa54:       00 00 00 60     nop
    10fa58:       ac f4 ff 4b     b       10ef04 &lt;gaih_inet.constprop.7+0x3f4&gt;
  ...
  0000000000110450 &lt;getaddrinfo&gt;:
  ...
    1105a8:       54 00 ff 38     addi    r7,r31,84
    1105ac:       58 00 df 38     addi    r6,r31,88
    1105b0:       69 e5 ff 4b     bl      10eb18 &lt;gaih_inet.constprop.7+0x8&gt;
    1105b4:       78 1b 71 7c     mr      r17,r3
    1105b8:       50 01 7f e8     ld      r3,336(r31)
  ...
  000000000015af20 &lt;inet_pton&gt;:
    15af20:       0b 00 4c 3c     addis   r2,r12,11
    15af24:       e0 c1 42 38     addi    r2,r2,-15904
    15af28:       a6 02 08 7c     mflr    r0
    15af2c:       f0 ff c1 fb     std     r30,-16(r1)
    15af30:       f8 ff e1 fb     std     r31,-8(r1)
  ...

  # perf probe -x /usr/lib64/libc-2.26.so -a inet_pton+0x8
  # perf record -e probe_libc:inet_pton -g ping -6 -c 1 ::1
  # perf script

Before:

  ping  4507 [002] 514985.546540: probe_libc:inet_pton: (7fffa7dbaf28)
              7fffa7dbaf28 __GI___inet_pton+0x8 (/usr/lib64/libc-2.26.so)
              7fffa7d705b4 getaddrinfo+0x164 (/usr/lib64/libc-2.26.so)
                 13fb52d70 _init+0xbfc (/usr/bin/ping)
              7fffa7c836a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc-2.26.so)
              7fffa7c83898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so)
                         0 [unknown] ([unknown])

After:

  ping  4507 [002] 514985.546540: probe_libc:inet_pton: (7fffa7dbaf28)
              7fffa7dbaf28 __GI___inet_pton+0x8 (/usr/lib64/libc-2.26.so)
              7fffa7d6fa54 gaih_inet.constprop.7+0xf44 (/usr/lib64/libc-2.26.so)
              7fffa7d705b4 getaddrinfo+0x164 (/usr/lib64/libc-2.26.so)
                 13fb52d70 _init+0xbfc (/usr/bin/ping)
              7fffa7c836a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc-2.26.so)
              7fffa7c83898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so)
                         0 [unknown] ([unknown])

Case 2 - Attaching a probe at _int_malloc+0x180 (binary offset 0x9cf10).
         Return address in still in LR and a new stack frame has already
         been allocated but not used. The caller's caller, i.e. the third
	 entry, is invalid and should be filtered out and not the second
	 one.

  # objdump -d /usr/lib64/libc-2.26.so | less
  ...
  000000000009cd90 &lt;_int_malloc&gt;:
     9cd90:       17 00 4c 3c     addis   r2,r12,23
     9cd94:       70 a3 42 38     addi    r2,r2,-23696
     9cd98:       26 00 80 7d     mfcr    r12
     9cd9c:       f8 ff e1 fb     std     r31,-8(r1)
     9cda0:       17 00 e4 3b     addi    r31,r4,23
     9cda4:       d8 ff 61 fb     std     r27,-40(r1)
     9cda8:       78 23 9b 7c     mr      r27,r4
     9cdac:       1f 00 bf 2b     cmpldi  cr7,r31,31
     9cdb0:       f0 ff c1 fb     std     r30,-16(r1)
     9cdb4:       b0 ff c1 fa     std     r22,-80(r1)
     9cdb8:       78 1b 7e 7c     mr      r30,r3
     9cdbc:       08 00 81 91     stw     r12,8(r1)
     9cdc0:       11 ff 21 f8     stdu    r1,-240(r1)
     9cdc4:       4c 01 9d 41     bgt     cr7,9cf10 &lt;_int_malloc+0x180&gt;
     9cdc8:       20 00 a4 2b     cmpldi  cr7,r4,32
  ...
     9cf08:       00 00 00 60     nop
     9cf0c:       00 00 42 60     ori     r2,r2,0
     9cf10:       e4 06 ff 7b     rldicr  r31,r31,0,59
     9cf14:       40 f8 a4 7f     cmpld   cr7,r4,r31
     9cf18:       68 05 9d 41     bgt     cr7,9d480 &lt;_int_malloc+0x6f0&gt;
  ...
  000000000009e3c0 &lt;tcache_init.part.4&gt;:
  ...
     9e420:       40 02 80 38     li      r4,576
     9e424:       78 fb e3 7f     mr      r3,r31
     9e428:       71 e9 ff 4b     bl      9cd98 &lt;_int_malloc+0x8&gt;
     9e42c:       00 00 a3 2f     cmpdi   cr7,r3,0
     9e430:       78 1b 7e 7c     mr      r30,r3
  ...
  000000000009f7a0 &lt;__libc_malloc&gt;:
  ...
     9f8f8:       00 00 89 2f     cmpwi   cr7,r9,0
     9f8fc:       1c ff 9e 40     bne     cr7,9f818 &lt;__libc_malloc+0x78&gt;
     9f900:       c9 ea ff 4b     bl      9e3c8 &lt;tcache_init.part.4+0x8&gt;
     9f904:       00 00 00 60     nop
     9f908:       e8 90 22 e9     ld      r9,-28440(r2)
  ...

  # perf probe -x /usr/lib64/libc-2.26.so -a _int_malloc+0x180
  # perf record -e probe_libc:_int_malloc -g ./test-malloc
  # perf script

Before:

  test-malloc  6554 [009] 515975.797403: probe_libc:_int_malloc: (7fffa6e6cf10)
              7fffa6e6cf10 _int_malloc+0x180 (/usr/lib64/libc-2.26.so)
              7fffa6dd0000 [unknown] (/usr/lib64/libc-2.26.so)
              7fffa6e6f904 malloc+0x164 (/usr/lib64/libc-2.26.so)
              7fffa6e6f9fc malloc+0x25c (/usr/lib64/libc-2.26.so)
                  100006b4 main+0x38 (/home/testuser/test-malloc)
              7fffa6df36a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc-2.26.so)
              7fffa6df3898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so)
                         0 [unknown] ([unknown])

After:

  test-malloc  6554 [009] 515975.797403: probe_libc:_int_malloc: (7fffa6e6cf10)
              7fffa6e6cf10 _int_malloc+0x180 (/usr/lib64/libc-2.26.so)
              7fffa6e6e42c tcache_init.part.4+0x6c (/usr/lib64/libc-2.26.so)
              7fffa6e6f904 malloc+0x164 (/usr/lib64/libc-2.26.so)
              7fffa6e6f9fc malloc+0x25c (/usr/lib64/libc-2.26.so)
                  100006b4 main+0x38 (/home/sandipan/test-malloc)
              7fffa6df36a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc-2.26.so)
              7fffa6df3898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so)
                         0 [unknown] ([unknown])

Signed-off-by: Sandipan Das &lt;sandipan@linux.ibm.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Maynard Johnson &lt;maynard@us.ibm.com&gt;
Cc: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Cc: Ravi Bangoria &lt;ravi.bangoria@linux.vnet.ibm.com&gt;
Cc: Sukadev Bhattiprolu &lt;sukadev@linux.vnet.ibm.com&gt;
Fixes: a60335ba3298 ("perf tools powerpc: Adjust callchain based on DWARF debug info")
Link: http://lkml.kernel.org/r/24bb726d91ed173aebc972ec3f41a2ef2249434e.1530724939.git.sandipan@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf powerpc: Fix callchain ip filtering when return address is in a register</title>
<updated>2018-09-26T06:33:56+00:00</updated>
<author>
<name>Sandipan Das</name>
<email>sandipan@linux.ibm.com</email>
</author>
<published>2018-07-10T13:58:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2a227c0acd512fb90acec358a0858ec87cd377ca'/>
<id>2a227c0acd512fb90acec358a0858ec87cd377ca</id>
<content type='text'>
[ Upstream commit 9068533e4f470daf2b0f29c71d865990acd8826e ]

For powerpc64, perf will filter out the second entry in the callchain,
i.e. the LR value, if the return address of the function corresponding
to the probed location has already been saved on its caller's stack.

The state of the return address is determined using debug information.
At any point within a function, if the return address is already saved
somewhere, a DWARF expression can tell us about its location. If the
return address in still in LR only, no DWARF expression would exist.

Typically, the instructions in a function's prologue first copy the LR
value to R0 and then pushes R0 on to the stack. If LR has already been
copied to R0 but R0 is yet to be pushed to the stack, we can still get a
DWARF expression that says that the return address is in R0. This is
indicating that getting a DWARF expression for the return address does
not guarantee the fact that it has already been saved on the stack.

This can be observed on a powerpc64le system running Fedora 27 as shown
below.

  # objdump -d /usr/lib64/libc-2.26.so | less
  ...
  000000000015af20 &lt;inet_pton&gt;:
    15af20:       0b 00 4c 3c     addis   r2,r12,11
    15af24:       e0 c1 42 38     addi    r2,r2,-15904
    15af28:       a6 02 08 7c     mflr    r0
    15af2c:       f0 ff c1 fb     std     r30,-16(r1)
    15af30:       f8 ff e1 fb     std     r31,-8(r1)
    15af34:       78 1b 7f 7c     mr      r31,r3
    15af38:       78 23 83 7c     mr      r3,r4
    15af3c:       78 2b be 7c     mr      r30,r5
    15af40:       10 00 01 f8     std     r0,16(r1)
    15af44:       c1 ff 21 f8     stdu    r1,-64(r1)
    15af48:       28 00 81 f8     std     r4,40(r1)
  ...

  # readelf --debug-dump=frames-interp /usr/lib64/libc-2.26.so | less
  ...
  00027024 0000000000000024 00027028 FDE cie=00000000 pc=000000000015af20..000000000015af88
     LOC           CFA      r30   r31   ra
  000000000015af20 r1+0     u     u     u
  000000000015af34 r1+0     c-16  c-8   r0
  000000000015af48 r1+64    c-16  c-8   c+16
  000000000015af5c r1+0     c-16  c-8   c+16
  000000000015af78 r1+0     u     u
  ...

  # perf probe -x /usr/lib64/libc-2.26.so -a inet_pton+0x18
  # perf record -e probe_libc:inet_pton -g ping -6 -c 1 ::1
  # perf script

Before:

  ping  2829 [005] 512917.460174: probe_libc:inet_pton: (7fff7e2baf38)
              7fff7e2baf38 __GI___inet_pton+0x18 (/usr/lib64/libc-2.26.so)
              7fff7e2705b4 getaddrinfo+0x164 (/usr/lib64/libc-2.26.so)
                 12f152d70 _init+0xbfc (/usr/bin/ping)
              7fff7e1836a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc-2.26.so)
              7fff7e183898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so)
                         0 [unknown] ([unknown])

After:

  ping  2829 [005] 512917.460174: probe_libc:inet_pton: (7fff7e2baf38)
              7fff7e2baf38 __GI___inet_pton+0x18 (/usr/lib64/libc-2.26.so)
              7fff7e26fa54 gaih_inet.constprop.7+0xf44 (/usr/lib64/libc-2.26.so)
              7fff7e2705b4 getaddrinfo+0x164 (/usr/lib64/libc-2.26.so)
                 12f152d70 _init+0xbfc (/usr/bin/ping)
              7fff7e1836a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc-2.26.so)
              7fff7e183898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so)
                         0 [unknown] ([unknown])

Reported-by: Ravi Bangoria &lt;ravi.bangoria@linux.ibm.com&gt;
Signed-off-by: Sandipan Das &lt;sandipan@linux.ibm.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Maynard Johnson &lt;maynard@us.ibm.com&gt;
Cc: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Cc: Ravi Bangoria &lt;ravi.bangoria@linux.vnet.ibm.com&gt;
Cc: Sukadev Bhattiprolu &lt;sukadev@linux.vnet.ibm.com&gt;
Link: http://lkml.kernel.org/r/66e848a7bdf2d43b39210a705ff6d828a0865661.1530724939.git.sandipan@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 9068533e4f470daf2b0f29c71d865990acd8826e ]

For powerpc64, perf will filter out the second entry in the callchain,
i.e. the LR value, if the return address of the function corresponding
to the probed location has already been saved on its caller's stack.

The state of the return address is determined using debug information.
At any point within a function, if the return address is already saved
somewhere, a DWARF expression can tell us about its location. If the
return address in still in LR only, no DWARF expression would exist.

Typically, the instructions in a function's prologue first copy the LR
value to R0 and then pushes R0 on to the stack. If LR has already been
copied to R0 but R0 is yet to be pushed to the stack, we can still get a
DWARF expression that says that the return address is in R0. This is
indicating that getting a DWARF expression for the return address does
not guarantee the fact that it has already been saved on the stack.

This can be observed on a powerpc64le system running Fedora 27 as shown
below.

  # objdump -d /usr/lib64/libc-2.26.so | less
  ...
  000000000015af20 &lt;inet_pton&gt;:
    15af20:       0b 00 4c 3c     addis   r2,r12,11
    15af24:       e0 c1 42 38     addi    r2,r2,-15904
    15af28:       a6 02 08 7c     mflr    r0
    15af2c:       f0 ff c1 fb     std     r30,-16(r1)
    15af30:       f8 ff e1 fb     std     r31,-8(r1)
    15af34:       78 1b 7f 7c     mr      r31,r3
    15af38:       78 23 83 7c     mr      r3,r4
    15af3c:       78 2b be 7c     mr      r30,r5
    15af40:       10 00 01 f8     std     r0,16(r1)
    15af44:       c1 ff 21 f8     stdu    r1,-64(r1)
    15af48:       28 00 81 f8     std     r4,40(r1)
  ...

  # readelf --debug-dump=frames-interp /usr/lib64/libc-2.26.so | less
  ...
  00027024 0000000000000024 00027028 FDE cie=00000000 pc=000000000015af20..000000000015af88
     LOC           CFA      r30   r31   ra
  000000000015af20 r1+0     u     u     u
  000000000015af34 r1+0     c-16  c-8   r0
  000000000015af48 r1+64    c-16  c-8   c+16
  000000000015af5c r1+0     c-16  c-8   c+16
  000000000015af78 r1+0     u     u
  ...

  # perf probe -x /usr/lib64/libc-2.26.so -a inet_pton+0x18
  # perf record -e probe_libc:inet_pton -g ping -6 -c 1 ::1
  # perf script

Before:

  ping  2829 [005] 512917.460174: probe_libc:inet_pton: (7fff7e2baf38)
              7fff7e2baf38 __GI___inet_pton+0x18 (/usr/lib64/libc-2.26.so)
              7fff7e2705b4 getaddrinfo+0x164 (/usr/lib64/libc-2.26.so)
                 12f152d70 _init+0xbfc (/usr/bin/ping)
              7fff7e1836a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc-2.26.so)
              7fff7e183898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so)
                         0 [unknown] ([unknown])

After:

  ping  2829 [005] 512917.460174: probe_libc:inet_pton: (7fff7e2baf38)
              7fff7e2baf38 __GI___inet_pton+0x18 (/usr/lib64/libc-2.26.so)
              7fff7e26fa54 gaih_inet.constprop.7+0xf44 (/usr/lib64/libc-2.26.so)
              7fff7e2705b4 getaddrinfo+0x164 (/usr/lib64/libc-2.26.so)
                 12f152d70 _init+0xbfc (/usr/bin/ping)
              7fff7e1836a0 generic_start_main.isra.0+0x140 (/usr/lib64/libc-2.26.so)
              7fff7e183898 __libc_start_main+0xb8 (/usr/lib64/libc-2.26.so)
                         0 [unknown] ([unknown])

Reported-by: Ravi Bangoria &lt;ravi.bangoria@linux.ibm.com&gt;
Signed-off-by: Sandipan Das &lt;sandipan@linux.ibm.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Maynard Johnson &lt;maynard@us.ibm.com&gt;
Cc: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Cc: Ravi Bangoria &lt;ravi.bangoria@linux.vnet.ibm.com&gt;
Cc: Sukadev Bhattiprolu &lt;sukadev@linux.vnet.ibm.com&gt;
Link: http://lkml.kernel.org/r/66e848a7bdf2d43b39210a705ff6d828a0865661.1530724939.git.sandipan@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf report powerpc: Fix crash if callchain is empty</title>
<updated>2018-08-28T05:21:35+00:00</updated>
<author>
<name>Sandipan Das</name>
<email>sandipan@linux.ibm.com</email>
</author>
<published>2018-06-11T10:40:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=915d80fd2060502aa2301bf6ae4639cb7313b09a'/>
<id>915d80fd2060502aa2301bf6ae4639cb7313b09a</id>
<content type='text'>
[ Upstream commit 143c99f6ac6812d23254e80844d6e34be897d3e1 ]

For some cases, the callchain provided by the kernel may be empty. So,
the callchain ip filtering code will cause a crash if we do not check
whether the struct ip_callchain pointer is NULL before accessing any
members.

This can be observed on a powerpc64le system running Fedora 27 as shown
below.

  # perf record -b -e cycles:u ls

Before:

  # perf report --branch-history

  perf: Segmentation fault
  -------- backtrace --------
  perf[0x1027615c]
  linux-vdso64.so.1(__kernel_sigtramp_rt64+0x0)[0x7fff856304d8]
  perf(arch_skip_callchain_idx+0x44)[0x10257c58]
  perf[0x1017f2e4]
  perf(thread__resolve_callchain+0x124)[0x1017ff5c]
  perf(sample__resolve_callchain+0xf0)[0x10172788]
  ...

After:

  # perf report --branch-history

  Samples: 25  of event 'cycles:u', Event count (approx.): 2306870
    Overhead  Source:Line            Symbol                   Shared Object
  +   11.60%  _init+35736            [.] _init                ls
  +    9.84%  strcoll_l.c:137        [.] __strcoll_l          libc-2.26.so
  +    9.16%  memcpy.S:175           [.] __memcpy_power7      libc-2.26.so
  +    9.01%  gconv_charset.h:54     [.] _nl_find_locale      libc-2.26.so
  +    8.87%  dl-addr.c:52           [.] _dl_addr             libc-2.26.so
  +    8.83%  _init+236              [.] _init                ls
  ...

Reported-by: Ravi Bangoria &lt;ravi.bangoria@linux.ibm.com&gt;
Signed-off-by: Sandipan Das &lt;sandipan@linux.ibm.com&gt;
Acked-by: Ravi Bangoria &lt;ravi.bangoria@linux.ibm.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Cc: Sukadev Bhattiprolu &lt;sukadev@linux.vnet.ibm.com&gt;
Link: http://lkml.kernel.org/r/20180611104049.11048-1-sandipan@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 143c99f6ac6812d23254e80844d6e34be897d3e1 ]

For some cases, the callchain provided by the kernel may be empty. So,
the callchain ip filtering code will cause a crash if we do not check
whether the struct ip_callchain pointer is NULL before accessing any
members.

This can be observed on a powerpc64le system running Fedora 27 as shown
below.

  # perf record -b -e cycles:u ls

Before:

  # perf report --branch-history

  perf: Segmentation fault
  -------- backtrace --------
  perf[0x1027615c]
  linux-vdso64.so.1(__kernel_sigtramp_rt64+0x0)[0x7fff856304d8]
  perf(arch_skip_callchain_idx+0x44)[0x10257c58]
  perf[0x1017f2e4]
  perf(thread__resolve_callchain+0x124)[0x1017ff5c]
  perf(sample__resolve_callchain+0xf0)[0x10172788]
  ...

After:

  # perf report --branch-history

  Samples: 25  of event 'cycles:u', Event count (approx.): 2306870
    Overhead  Source:Line            Symbol                   Shared Object
  +   11.60%  _init+35736            [.] _init                ls
  +    9.84%  strcoll_l.c:137        [.] __strcoll_l          libc-2.26.so
  +    9.16%  memcpy.S:175           [.] __memcpy_power7      libc-2.26.so
  +    9.01%  gconv_charset.h:54     [.] _nl_find_locale      libc-2.26.so
  +    8.87%  dl-addr.c:52           [.] _dl_addr             libc-2.26.so
  +    8.83%  _init+236              [.] _init                ls
  ...

Reported-by: Ravi Bangoria &lt;ravi.bangoria@linux.ibm.com&gt;
Signed-off-by: Sandipan Das &lt;sandipan@linux.ibm.com&gt;
Acked-by: Ravi Bangoria &lt;ravi.bangoria@linux.ibm.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Cc: Sukadev Bhattiprolu &lt;sukadev@linux.vnet.ibm.com&gt;
Link: http://lkml.kernel.org/r/20180611104049.11048-1-sandipan@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
