<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/tools/perf/util, branch linux-3.14.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>perf header: Fixup reading of HEADER_NRCPUS feature</title>
<updated>2015-10-22T21:39:17+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2015-09-11T15:36:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4688a16e79d81c85564711a48914992f81b2286c'/>
<id>4688a16e79d81c85564711a48914992f81b2286c</id>
<content type='text'>
commit caa470475d9b59eeff093ae650800d34612c4379 upstream.

The original patch introducing this header wrote the number of CPUs available
and online in one order and then swapped those values when reading, fix it.

Before:

  # perf record usleep 1
  # perf report --header-only | grep 'nrcpus \(online\|avail\)'
  # nrcpus online : 4
  # nrcpus avail : 4
  # echo 0 &gt; /sys/devices/system/cpu/cpu2/online
  # perf record usleep 1
  # perf report --header-only | grep 'nrcpus \(online\|avail\)'
  # nrcpus online : 4
  # nrcpus avail : 3
  # echo 0 &gt; /sys/devices/system/cpu/cpu1/online
  # perf record usleep 1
  # perf report --header-only | grep 'nrcpus \(online\|avail\)'
  # nrcpus online : 4
  # nrcpus avail : 2

After the fix, bringing back the CPUs online:

  # perf report --header-only | grep 'nrcpus \(online\|avail\)'
  # nrcpus online : 2
  # nrcpus avail : 4
  # echo 1 &gt; /sys/devices/system/cpu/cpu2/online
  # perf record usleep 1
  # perf report --header-only | grep 'nrcpus \(online\|avail\)'
  # nrcpus online : 3
  # nrcpus avail : 4
  # echo 1 &gt; /sys/devices/system/cpu/cpu1/online
  # perf record usleep 1
  # perf report --header-only | grep 'nrcpus \(online\|avail\)'
  # nrcpus online : 4
  # nrcpus avail : 4

Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Borislav Petkov &lt;bp@suse.de&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Kan Liang &lt;kan.liang@intel.com&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Fixes: fbe96f29ce4b ("perf tools: Make perf.data more self-descriptive (v8)")
Link: http://lkml.kernel.org/r/20150911153323.GP23511@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.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>
commit caa470475d9b59eeff093ae650800d34612c4379 upstream.

The original patch introducing this header wrote the number of CPUs available
and online in one order and then swapped those values when reading, fix it.

Before:

  # perf record usleep 1
  # perf report --header-only | grep 'nrcpus \(online\|avail\)'
  # nrcpus online : 4
  # nrcpus avail : 4
  # echo 0 &gt; /sys/devices/system/cpu/cpu2/online
  # perf record usleep 1
  # perf report --header-only | grep 'nrcpus \(online\|avail\)'
  # nrcpus online : 4
  # nrcpus avail : 3
  # echo 0 &gt; /sys/devices/system/cpu/cpu1/online
  # perf record usleep 1
  # perf report --header-only | grep 'nrcpus \(online\|avail\)'
  # nrcpus online : 4
  # nrcpus avail : 2

After the fix, bringing back the CPUs online:

  # perf report --header-only | grep 'nrcpus \(online\|avail\)'
  # nrcpus online : 2
  # nrcpus avail : 4
  # echo 1 &gt; /sys/devices/system/cpu/cpu2/online
  # perf record usleep 1
  # perf report --header-only | grep 'nrcpus \(online\|avail\)'
  # nrcpus online : 3
  # nrcpus avail : 4
  # echo 1 &gt; /sys/devices/system/cpu/cpu1/online
  # perf record usleep 1
  # perf report --header-only | grep 'nrcpus \(online\|avail\)'
  # nrcpus online : 4
  # nrcpus avail : 4

Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Borislav Petkov &lt;bp@suse.de&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Kan Liang &lt;kan.liang@intel.com&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Fixes: fbe96f29ce4b ("perf tools: Make perf.data more self-descriptive (v8)")
Link: http://lkml.kernel.org/r/20150911153323.GP23511@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>perf hists: Update the column width for the "srcline" sort key</title>
<updated>2015-10-22T21:39:17+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2015-08-10T19:53:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8172440d38215ba5b7a7cab09d17c47d37a71e0f'/>
<id>8172440d38215ba5b7a7cab09d17c47d37a71e0f</id>
<content type='text'>
commit e8e6d37e73e6b950c891c780745460b87f4755b6 upstream.

When we introduce a new sort key, we need to update the
hists__calc_col_len() function accordingly, otherwise the width
will be limited to strlen(header).

We can't update it when obtaining a line value for a column (for
instance, in sort__srcline_cmp()), because we reset it all when doing a
resort (see hists__output_recalc_col_len()), so we need to, from what is
in the hist_entry fields, set each of the column widths.

Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Andi Kleen &lt;andi@firstfloor.org&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Fixes: 409a8be61560 ("perf tools: Add sort by src line/number")
Link: http://lkml.kernel.org/n/tip-jgbe0yx8v1gs89cslr93pvz2@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.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>
commit e8e6d37e73e6b950c891c780745460b87f4755b6 upstream.

When we introduce a new sort key, we need to update the
hists__calc_col_len() function accordingly, otherwise the width
will be limited to strlen(header).

We can't update it when obtaining a line value for a column (for
instance, in sort__srcline_cmp()), because we reset it all when doing a
resort (see hists__output_recalc_col_len()), so we need to, from what is
in the hist_entry fields, set each of the column widths.

Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Andi Kleen &lt;andi@firstfloor.org&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Fixes: 409a8be61560 ("perf tools: Add sort by src line/number")
Link: http://lkml.kernel.org/n/tip-jgbe0yx8v1gs89cslr93pvz2@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>perf tools: Fix copying of /proc/kcore</title>
<updated>2015-10-22T21:39:17+00:00</updated>
<author>
<name>Adrian Hunter</name>
<email>adrian.hunter@intel.com</email>
</author>
<published>2015-09-24T10:05:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3de5bd0b9791f0e6eb1257a1d8ef979890c989ac'/>
<id>3de5bd0b9791f0e6eb1257a1d8ef979890c989ac</id>
<content type='text'>
commit b5cabbcbd157a4bf5a92dfc85134999a3b55342d upstream.

A copy of /proc/kcore containing the kernel text can be made to the
buildid cache. e.g.

	perf buildid-cache -v -k /proc/kcore

To workaround objdump limitations, a copy is also made when annotating
against /proc/kcore.

The copying process stops working from libelf about v1.62 onwards (the
problem was found with v1.63).

The cause is that a call to gelf_getphdr() in kcore__add_phdr() fails
because additional validation has been added to gelf_getphdr().

The use of gelf_getphdr() is a misguided attempt to get default
initialization of the Gelf_Phdr structure.  That should not be
necessary because every member of the Gelf_Phdr structure is
subsequently assigned.  So just remove the call to gelf_getphdr().

Similarly, a call to gelf_getehdr() in gelf_kcore__init() can be
removed also.

Committer notes:

Note to stable@kernel.org, from Adrian in the cover letter for this
patchkit:

The "Fix copying of /proc/kcore" problem goes back to v3.13 if you think
it is important enough for stable.

Signed-off-by: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Link: http://lkml.kernel.org/r/1443089122-19082-3-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.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>
commit b5cabbcbd157a4bf5a92dfc85134999a3b55342d upstream.

A copy of /proc/kcore containing the kernel text can be made to the
buildid cache. e.g.

	perf buildid-cache -v -k /proc/kcore

To workaround objdump limitations, a copy is also made when annotating
against /proc/kcore.

The copying process stops working from libelf about v1.62 onwards (the
problem was found with v1.63).

The cause is that a call to gelf_getphdr() in kcore__add_phdr() fails
because additional validation has been added to gelf_getphdr().

The use of gelf_getphdr() is a misguided attempt to get default
initialization of the Gelf_Phdr structure.  That should not be
necessary because every member of the Gelf_Phdr structure is
subsequently assigned.  So just remove the call to gelf_getphdr().

Similarly, a call to gelf_getehdr() in gelf_kcore__init() can be
removed also.

Committer notes:

Note to stable@kernel.org, from Adrian in the cover letter for this
patchkit:

The "Fix copying of /proc/kcore" problem goes back to v3.13 if you think
it is important enough for stable.

Signed-off-by: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Link: http://lkml.kernel.org/r/1443089122-19082-3-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>perf session: Do not fail on processing out of order event</title>
<updated>2015-01-16T14:59:34+00:00</updated>
<author>
<name>Jiri Olsa</name>
<email>jolsa@kernel.org</email>
</author>
<published>2014-11-26T15:39:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ceaefcdf2a9f24835691d58d45c5cc50d596a7d0'/>
<id>ceaefcdf2a9f24835691d58d45c5cc50d596a7d0</id>
<content type='text'>
commit f61ff6c06dc8f32c7036013ad802c899ec590607 upstream.

Linus reported perf report command being interrupted due to processing
of 'out of order' event, with following error:

  Timestamp below last timeslice flush
  0x5733a8 [0x28]: failed to process type: 3

I could reproduce the issue and in my case it was caused by one CPU
(mmap) being behind during record and userspace mmap reader seeing the
data after other CPUs data were already stored.

This is expected under some circumstances because we need to limit the
number of events that we queue for reordering when we receive a
PERF_RECORD_FINISHED_ROUND or when we force flush due to memory
pressure.

Reported-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Acked-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Corey Ashford &lt;cjashfor@linux.vnet.ibm.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Matt Fleming &lt;matt.fleming@intel.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Link: http://lkml.kernel.org/r/1417016371-30249-1-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
[zhangzhiqiang: backport to 3.10:
 - adjust context
 - commit f61ff6c06d struct events_stats was defined in tools/perf/util/event.h
   while 3.10 stable defined in tools/perf/util/hist.h.
 - 3.10 stable there is no pr_oe_time() which used for debug.
 - After the above adjustments, becomes same to the original patch:
   https://github.com/torvalds/linux/commit/f61ff6c06dc8f32c7036013ad802c899ec590607
]
Signed-off-by: Zhiqiang Zhang &lt;zhangzhiqiang.zhang@huawei.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>
commit f61ff6c06dc8f32c7036013ad802c899ec590607 upstream.

Linus reported perf report command being interrupted due to processing
of 'out of order' event, with following error:

  Timestamp below last timeslice flush
  0x5733a8 [0x28]: failed to process type: 3

I could reproduce the issue and in my case it was caused by one CPU
(mmap) being behind during record and userspace mmap reader seeing the
data after other CPUs data were already stored.

This is expected under some circumstances because we need to limit the
number of events that we queue for reordering when we receive a
PERF_RECORD_FINISHED_ROUND or when we force flush due to memory
pressure.

Reported-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Acked-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Corey Ashford &lt;cjashfor@linux.vnet.ibm.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Matt Fleming &lt;matt.fleming@intel.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Link: http://lkml.kernel.org/r/1417016371-30249-1-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
[zhangzhiqiang: backport to 3.10:
 - adjust context
 - commit f61ff6c06d struct events_stats was defined in tools/perf/util/event.h
   while 3.10 stable defined in tools/perf/util/hist.h.
 - 3.10 stable there is no pr_oe_time() which used for debug.
 - After the above adjustments, becomes same to the original patch:
   https://github.com/torvalds/linux/commit/f61ff6c06dc8f32c7036013ad802c899ec590607
]
Signed-off-by: Zhiqiang Zhang &lt;zhangzhiqiang.zhang@huawei.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf machine: Use map as success in ip__resolve_ams</title>
<updated>2014-03-10T14:19:36+00:00</updated>
<author>
<name>Don Zickus</name>
<email>dzickus@redhat.com</email>
</author>
<published>2014-02-26T03:43:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fdf57dd052d5cbd415533ae98f4d423286a85220'/>
<id>fdf57dd052d5cbd415533ae98f4d423286a85220</id>
<content type='text'>
When trying to map a bunch of instruction addresses to their respective
threads, I kept getting a lot of bogus entries [I forget the exact
reason as I patched my code months ago].

Looking through ip__resolve_ams, I noticed the check for

  if (al.sym)

and realized, most times I have an al.map definition but sometimes an
al.sym is undefined.  In the cases where al.sym is undefined, the loop
keeps going even though a valid al.map exists.

Modify this check to use the more reliable al.map.  This fixed my bogus
entries.

Signed-off-by: Don Zickus &lt;dzickus@redhat.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Link: http://lkml.kernel.org/r/1393386227-149412-2-git-send-email-dzickus@redhat.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>
When trying to map a bunch of instruction addresses to their respective
threads, I kept getting a lot of bogus entries [I forget the exact
reason as I patched my code months ago].

Looking through ip__resolve_ams, I noticed the check for

  if (al.sym)

and realized, most times I have an al.map definition but sometimes an
al.sym is undefined.  In the cases where al.sym is undefined, the loop
keeps going even though a valid al.map exists.

Modify this check to use the more reliable al.map.  This fixed my bogus
entries.

Signed-off-by: Don Zickus &lt;dzickus@redhat.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Link: http://lkml.kernel.org/r/1393386227-149412-2-git-send-email-dzickus@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf symbols: Fix crash in elf_section_by_name</title>
<updated>2014-03-10T14:17:14+00:00</updated>
<author>
<name>Jiri Olsa</name>
<email>jolsa@redhat.com</email>
</author>
<published>2014-03-02T13:32:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=155b3a13a65d4217316dbe094843f2a7df0711fa'/>
<id>155b3a13a65d4217316dbe094843f2a7df0711fa</id>
<content type='text'>
Fixing crash in elf_section_by_name function caused by missing section
name in elf binary.

Reported-by: Albert Strasheim &lt;albert@cloudflare.com&gt;
Signed-off-by: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Albert Strasheim &lt;albert@cloudflare.com&gt;
Cc: Corey Ashford &lt;cjashfor@linux.vnet.ibm.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: Ingo Molnar &lt;mingo@elte.hu&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/1393767127-599-1-git-send-email-jolsa@redhat.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>
Fixing crash in elf_section_by_name function caused by missing section
name in elf binary.

Reported-by: Albert Strasheim &lt;albert@cloudflare.com&gt;
Signed-off-by: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Albert Strasheim &lt;albert@cloudflare.com&gt;
Cc: Corey Ashford &lt;cjashfor@linux.vnet.ibm.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: Ingo Molnar &lt;mingo@elte.hu&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/1393767127-599-1-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf tools: Fix strict alias issue for find_first_bit</title>
<updated>2014-02-28T13:39:40+00:00</updated>
<author>
<name>Jiri Olsa</name>
<email>jolsa@redhat.com</email>
</author>
<published>2014-02-26T17:14:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b39c2a57a00a841f057a75b41df4c26173288b66'/>
<id>b39c2a57a00a841f057a75b41df4c26173288b66</id>
<content type='text'>
When compiling perf tool code with gcc 4.4.7 I'm getting
following error:

    CC       util/session.o
  cc1: warnings being treated as errors
  util/session.c: In function ‘perf_session_deliver_event’:
  tools/perf/util/include/linux/bitops.h:109: error: dereferencing pointer ‘p’ does break strict-aliasing rules
  tools/perf/util/include/linux/bitops.h:101: error: dereferencing pointer ‘p’ does break strict-aliasing rules
  util/session.c:697: note: initialized from here
  tools/perf/util/include/linux/bitops.h:101: note: initialized from here
  make[1]: *** [util/session.o] Error 1
  make: *** [util/session.o] Error 2

The aliased types here are u64 and unsigned long pointers, which is safe
for the find_first_bit processing.

This error shows up for me only for gcc 4.4 on 32bit x86, even for
-Wstrict-aliasing=3, while newer gcc are quiet and scream here for
-Wstrict-aliasing={2,1}. Looks like newer gcc changed the rules for
strict alias warnings.

The gcc documentation offers workaround for valid aliasing by using
__may_alias__ attribute:

  http://gcc.gnu.org/onlinedocs/gcc-4.4.0/gcc/Type-Attributes.html

Using this workaround for the find_first_bit function.

Signed-off-by: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Corey Ashford &lt;cjashfor@linux.vnet.ibm.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: Ingo Molnar &lt;mingo@elte.hu&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/1393434867-20271-1-git-send-email-jolsa@redhat.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>
When compiling perf tool code with gcc 4.4.7 I'm getting
following error:

    CC       util/session.o
  cc1: warnings being treated as errors
  util/session.c: In function ‘perf_session_deliver_event’:
  tools/perf/util/include/linux/bitops.h:109: error: dereferencing pointer ‘p’ does break strict-aliasing rules
  tools/perf/util/include/linux/bitops.h:101: error: dereferencing pointer ‘p’ does break strict-aliasing rules
  util/session.c:697: note: initialized from here
  tools/perf/util/include/linux/bitops.h:101: note: initialized from here
  make[1]: *** [util/session.o] Error 1
  make: *** [util/session.o] Error 2

The aliased types here are u64 and unsigned long pointers, which is safe
for the find_first_bit processing.

This error shows up for me only for gcc 4.4 on 32bit x86, even for
-Wstrict-aliasing=3, while newer gcc are quiet and scream here for
-Wstrict-aliasing={2,1}. Looks like newer gcc changed the rules for
strict alias warnings.

The gcc documentation offers workaround for valid aliasing by using
__may_alias__ attribute:

  http://gcc.gnu.org/onlinedocs/gcc-4.4.0/gcc/Type-Attributes.html

Using this workaround for the find_first_bit function.

Signed-off-by: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Corey Ashford &lt;cjashfor@linux.vnet.ibm.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: Ingo Molnar &lt;mingo@elte.hu&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/1393434867-20271-1-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf symbols: Destroy unused symsrcs</title>
<updated>2014-02-24T14:13:08+00:00</updated>
<author>
<name>Namhyung Kim</name>
<email>namhyung@kernel.org</email>
</author>
<published>2014-02-20T01:32:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=98e9f03bbf2cb21a60f94b8b700eb5d38470819d'/>
<id>98e9f03bbf2cb21a60f94b8b700eb5d38470819d</id>
<content type='text'>
Stephane reported that perf report and annotate failed to process data
using lots of (&gt; 500) shared libraries.  It was because of the limit on
number of open files (ulimit -n).

Currently when perf loads a DSO, it'll look for normal and dynamic
symbol tables.  And if it fails to find out both tables, it'll iterate
all of possible symtab types.  But many of them are useless since they
have no additional information and the problem is that it's not closing
those files even though they're not used.  Fix it.

Reported-by: Stephane Eranian &lt;eranian@google.com&gt;
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Cody P Schafer &lt;cody@linux.vnet.ibm.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung.kim@lge.com&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/1392859976-32760-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Stephane reported that perf report and annotate failed to process data
using lots of (&gt; 500) shared libraries.  It was because of the limit on
number of open files (ulimit -n).

Currently when perf loads a DSO, it'll look for normal and dynamic
symbol tables.  And if it fails to find out both tables, it'll iterate
all of possible symtab types.  But many of them are useless since they
have no additional information and the problem is that it's not closing
those files even though they're not used.  Fix it.

Reported-by: Stephane Eranian &lt;eranian@google.com&gt;
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Cody P Schafer &lt;cody@linux.vnet.ibm.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung.kim@lge.com&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/1392859976-32760-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf annotate: Check availability of annotate when processing samples</title>
<updated>2014-02-24T14:12:55+00:00</updated>
<author>
<name>Namhyung Kim</name>
<email>namhyung@kernel.org</email>
</author>
<published>2014-02-20T01:32:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=48c65bda95d692076de7e5eae3188ddae8635dca'/>
<id>48c65bda95d692076de7e5eae3188ddae8635dca</id>
<content type='text'>
The TUI of perf report and top support annotation, but stdio and GTK
don't.  So it should be checked before calling hist_entry__inc_addr_
samples() to avoid wasting resources that will never be used.

perf annotate need it regardless of UI and sort keys, so the check
of whether to allocate resources should be on the tools that have
annotate as an option in the TUI, 'report' and 'top', not on the
function called by all of them.

It caused perf annotate on ppc64 to produce zero output, since the
buckets were not being allocated.

Reported-by: Anton Blanchard &lt;anton@samba.org&gt;
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Anton Blanchard &lt;anton@samba.org&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung.kim@lge.com&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/1392859976-32760-1-git-send-email-namhyung@kernel.org
[ Renamed (report,top)__needs_annotate() to ui__has_annotation() ]
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 TUI of perf report and top support annotation, but stdio and GTK
don't.  So it should be checked before calling hist_entry__inc_addr_
samples() to avoid wasting resources that will never be used.

perf annotate need it regardless of UI and sort keys, so the check
of whether to allocate resources should be on the tools that have
annotate as an option in the TUI, 'report' and 'top', not on the
function called by all of them.

It caused perf annotate on ppc64 to produce zero output, since the
buckets were not being allocated.

Reported-by: Anton Blanchard &lt;anton@samba.org&gt;
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Anton Blanchard &lt;anton@samba.org&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung.kim@lge.com&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/1392859976-32760-1-git-send-email-namhyung@kernel.org
[ Renamed (report,top)__needs_annotate() to ui__has_annotation() ]
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf list: Fix checking for supported events on older kernels</title>
<updated>2014-02-10T14:34:31+00:00</updated>
<author>
<name>Vince Weaver</name>
<email>vincent.weaver@maine.edu</email>
</author>
<published>2013-12-30T20:39:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=88fee52e58ca14d8465b614774ed0bf08e1a7790'/>
<id>88fee52e58ca14d8465b614774ed0bf08e1a7790</id>
<content type='text'>
"perf list" listing of hardware events doesn't work on older ARM devices.
The change enabling event detection:

 commit b41f1cec91c37eeea6fdb15effbfa24ea0a5536b
 Author: Namhyung Kim &lt;namhyung.kim@lge.com&gt;
 Date:   Tue Aug 27 11:41:53 2013 +0900

     perf list: Skip unsupported events

uses the following code in tools/perf/util/parse-events.c:

        struct perf_event_attr attr = {
                .type = type,
                .config = config,
                .disabled = 1,
                .exclude_kernel = 1,
        };

On ARM machines pre-dating the Cortex-A15 this doesn't work, as these
machines don't support .exclude_kernel.  So starting with 3.12 "perf
list" does not report any hardware events at all on older machines (seen
on Rasp-Pi, Pandaboard, Beagleboard, etc).

This version of the patch makes changes suggested by Namhyung Kim to
check for EACCESS and retry (instead of just dropping the
exclude_kernel) so we can properly handle machines where
/proc/sys/kernel/perf_event_paranoid is set to 2.

Reported-by: Chad Paradis &lt;chad.paradis@umit.maine.edu&gt;
Signed-off-by: Vince Weaver &lt;vincent.weaver@maine.edu&gt;
Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Chad Paradis &lt;chad.paradis@umit.maine.edu&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1312301536150.28814@vincent-weaver-1.um.maine.edu
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>
"perf list" listing of hardware events doesn't work on older ARM devices.
The change enabling event detection:

 commit b41f1cec91c37eeea6fdb15effbfa24ea0a5536b
 Author: Namhyung Kim &lt;namhyung.kim@lge.com&gt;
 Date:   Tue Aug 27 11:41:53 2013 +0900

     perf list: Skip unsupported events

uses the following code in tools/perf/util/parse-events.c:

        struct perf_event_attr attr = {
                .type = type,
                .config = config,
                .disabled = 1,
                .exclude_kernel = 1,
        };

On ARM machines pre-dating the Cortex-A15 this doesn't work, as these
machines don't support .exclude_kernel.  So starting with 3.12 "perf
list" does not report any hardware events at all on older machines (seen
on Rasp-Pi, Pandaboard, Beagleboard, etc).

This version of the patch makes changes suggested by Namhyung Kim to
check for EACCESS and retry (instead of just dropping the
exclude_kernel) so we can properly handle machines where
/proc/sys/kernel/perf_event_paranoid is set to 2.

Reported-by: Chad Paradis &lt;chad.paradis@umit.maine.edu&gt;
Signed-off-by: Vince Weaver &lt;vincent.weaver@maine.edu&gt;
Acked-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Chad Paradis &lt;chad.paradis@umit.maine.edu&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1312301536150.28814@vincent-weaver-1.um.maine.edu
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
