<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/tools/perf/util, branch v3.0.7</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>perf symbols: Fix ppc64 SEGV in dso__load_sym with debuginfo files</title>
<updated>2011-10-03T18:41:02+00:00</updated>
<author>
<name>Anton Blanchard</name>
<email>anton@samba.org</email>
</author>
<published>2011-08-24T06:40:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8413239bfc9e8b94af509c7a43c7d92bd8965630'/>
<id>8413239bfc9e8b94af509c7a43c7d92bd8965630</id>
<content type='text'>
commit adb091846318f86e4f46c7d6a7b40d2f478abdbe upstream.

64bit PowerPC debuginfo files have an empty function descriptor section.
I hit a SEGV when perf tried to use this section for symbol resolution.

To fix this we need to check the section is valid and we can do this by
checking for type SHT_PROGBITS.

Cc: &lt;stable@kernel.org&gt;
Cc: Ingo Molnar &lt;mingo@elte.hu&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Eric B Munson &lt;emunson@mgebm.net&gt;
Link: http://lkml.kernel.org/r/20110824065242.895239970@samba.org
Signed-off-by: Anton Blanchard &lt;anton@samba.org&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@suse.de&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit adb091846318f86e4f46c7d6a7b40d2f478abdbe upstream.

64bit PowerPC debuginfo files have an empty function descriptor section.
I hit a SEGV when perf tried to use this section for symbol resolution.

To fix this we need to check the section is valid and we can do this by
checking for type SHT_PROGBITS.

Cc: &lt;stable@kernel.org&gt;
Cc: Ingo Molnar &lt;mingo@elte.hu&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Eric B Munson &lt;emunson@mgebm.net&gt;
Link: http://lkml.kernel.org/r/20110824065242.895239970@samba.org
Signed-off-by: Anton Blanchard &lt;anton@samba.org&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@suse.de&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>perf tools: do not look at ./config for configuration</title>
<updated>2011-08-17T17:55:54+00:00</updated>
<author>
<name>Jonathan Nieder</name>
<email>jrnieder@gmail.com</email>
</author>
<published>2011-08-05T16:58:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=cb52eec12483475b1c1dcea3d817528b5724a209'/>
<id>cb52eec12483475b1c1dcea3d817528b5724a209</id>
<content type='text'>
commit aba8d056078e47350d85b06a9cabd5afcc4b72ea upstream.

In addition to /etc/perfconfig and $HOME/.perfconfig, perf looks for
configuration in the file ./config, imitating git which looks at
$GIT_DIR/config.  If ./config is not a perf configuration file, it
fails, or worse, treats it as a configuration file and changes behavior
in some unexpected way.

"config" is not an unusual name for a file to be lying around and perf
does not have a private directory dedicated for its own use, so let's
just stop looking for configuration in the cwd.  Callers needing
context-sensitive configuration can use the PERF_CONFIG environment
variable.

Requested-by: Christian Ohm &lt;chr.ohm@gmx.net&gt;
Cc: 632923@bugs.debian.org
Cc: Ben Hutchings &lt;ben@decadent.org.uk&gt;
Cc: Christian Ohm &lt;chr.ohm@gmx.net&gt;
Cc: Ingo Molnar &lt;mingo@elte.hu&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/20110805165838.GA7237@elie.gateway.2wire.net
Signed-off-by: Jonathan Nieder &lt;jrnieder@gmail.com&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@suse.de&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit aba8d056078e47350d85b06a9cabd5afcc4b72ea upstream.

In addition to /etc/perfconfig and $HOME/.perfconfig, perf looks for
configuration in the file ./config, imitating git which looks at
$GIT_DIR/config.  If ./config is not a perf configuration file, it
fails, or worse, treats it as a configuration file and changes behavior
in some unexpected way.

"config" is not an unusual name for a file to be lying around and perf
does not have a private directory dedicated for its own use, so let's
just stop looking for configuration in the cwd.  Callers needing
context-sensitive configuration can use the PERF_CONFIG environment
variable.

Requested-by: Christian Ohm &lt;chr.ohm@gmx.net&gt;
Cc: 632923@bugs.debian.org
Cc: Ben Hutchings &lt;ben@decadent.org.uk&gt;
Cc: Christian Ohm &lt;chr.ohm@gmx.net&gt;
Cc: Ingo Molnar &lt;mingo@elte.hu&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/20110805165838.GA7237@elie.gateway.2wire.net
Signed-off-by: Jonathan Nieder &lt;jrnieder@gmail.com&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@suse.de&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>perf tools: Fix endian conversion reading event attr from file header</title>
<updated>2011-08-05T04:58:35+00:00</updated>
<author>
<name>David Ahern</name>
<email>dsahern@gmail.com</email>
</author>
<published>2011-07-15T18:34:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5dd830d09df97bc9318d6e0841fcf652bdc46bfa'/>
<id>5dd830d09df97bc9318d6e0841fcf652bdc46bfa</id>
<content type='text'>
commit eda3913bb70ecebac13adccffe1e7f96e93cee02 upstream.

The perf_event_attr struct has two __u32's at the top and
they need to be swapped individually.

With this change I was able to analyze a perf.data collected in a
32-bit PPC VM on an x86 system. I tested both 32-bit and 64-bit
binaries for the Intel analysis side; both read the PPC perf.data
file correctly.

-v2:
 - changed the existing perf_event__attr_swap() to swap only elements
   of perf_event_attr and exported it for use in swapping the
   attributes in the file header
 - updated swap_ops used for processing events

Signed-off-by: David Ahern &lt;dsahern@gmail.com&gt;
Acked-by: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: acme@ghostprotocols.net
Cc: peterz@infradead.org
Cc: paulus@samba.org
Link: http://lkml.kernel.org/r/1310754849-12474-1-git-send-email-dsahern@gmail.com
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@suse.de&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit eda3913bb70ecebac13adccffe1e7f96e93cee02 upstream.

The perf_event_attr struct has two __u32's at the top and
they need to be swapped individually.

With this change I was able to analyze a perf.data collected in a
32-bit PPC VM on an x86 system. I tested both 32-bit and 64-bit
binaries for the Intel analysis side; both read the PPC perf.data
file correctly.

-v2:
 - changed the existing perf_event__attr_swap() to swap only elements
   of perf_event_attr and exported it for use in swapping the
   attributes in the file header
 - updated swap_ops used for processing events

Signed-off-by: David Ahern &lt;dsahern@gmail.com&gt;
Acked-by: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: acme@ghostprotocols.net
Cc: peterz@infradead.org
Cc: paulus@samba.org
Link: http://lkml.kernel.org/r/1310754849-12474-1-git-send-email-dsahern@gmail.com
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@suse.de&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip</title>
<updated>2011-06-19T15:56:56+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2011-06-19T15:56:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=357ed6b1a110048ff8106f99092d6c4a7aadb45a'/>
<id>357ed6b1a110048ff8106f99092d6c4a7aadb45a</id>
<content type='text'>
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  rcu: Move RCU_BOOST #ifdefs to header file
  rcu: use softirq instead of kthreads except when RCU_BOOST=y
  rcu: Use softirq to address performance regression
  rcu: Simplify curing of load woes
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  rcu: Move RCU_BOOST #ifdefs to header file
  rcu: use softirq instead of kthreads except when RCU_BOOST=y
  rcu: Use softirq to address performance regression
  rcu: Simplify curing of load woes
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6</title>
<updated>2011-06-16T17:26:58+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2011-06-16T17:26:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7cc2ed05891f424c2e323bc1a368ddb5c78b90f2'/>
<id>7cc2ed05891f424c2e323bc1a368ddb5c78b90f2</id>
<content type='text'>
* 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
  kbuild: Call depmod.sh via shell
  perf: clear out make flags when calling kernel make kernelver
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
* 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
  kbuild: Call depmod.sh via shell
  perf: clear out make flags when calling kernel make kernelver
</pre>
</div>
</content>
</entry>
<entry>
<title>perf: clear out make flags when calling kernel make kernelver</title>
<updated>2011-06-15T20:12:55+00:00</updated>
<author>
<name>Andy Whitcroft</name>
<email>apw@canonical.com</email>
</author>
<published>2011-06-15T13:35:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=37aa9a2eb4d9b1a4aec1fd18bb2bb6bca029de27'/>
<id>37aa9a2eb4d9b1a4aec1fd18bb2bb6bca029de27</id>
<content type='text'>
When generating the perf version from the kernel version using 'make
kernelver' it is necessary to clear out any MAKEFLAGS otherwise they may
trigger additional output which pollute the contents.

Signed-off-by: Andy Whitcroft &lt;apw@canonical.com&gt;
Signed-off-by: Michal Marek &lt;mmarek@suse.cz&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When generating the perf version from the kernel version using 'make
kernelver' it is necessary to clear out any MAKEFLAGS otherwise they may
trigger additional output which pollute the contents.

Signed-off-by: Andy Whitcroft &lt;apw@canonical.com&gt;
Signed-off-by: Michal Marek &lt;mmarek@suse.cz&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>rcu: Use softirq to address performance regression</title>
<updated>2011-06-14T22:25:39+00:00</updated>
<author>
<name>Shaohua Li</name>
<email>shaohua.li@intel.com</email>
</author>
<published>2011-06-14T05:26:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=09223371deac67d08ca0b70bd18787920284c967'/>
<id>09223371deac67d08ca0b70bd18787920284c967</id>
<content type='text'>
Commit a26ac2455ffcf3(rcu: move TREE_RCU from softirq to kthread)
introduced performance regression. In an AIM7 test, this commit degraded
performance by about 40%.

The commit runs rcu callbacks in a kthread instead of softirq. We observed
high rate of context switch which is caused by this. Out test system has
64 CPUs and HZ is 1000, so we saw more than 64k context switch per second
which is caused by RCU's per-CPU kthread.  A trace showed that most of
the time the RCU per-CPU kthread doesn't actually handle any callbacks,
but instead just does a very small amount of work handling grace periods.
This means that RCU's per-CPU kthreads are making the scheduler do quite
a bit of work in order to allow a very small amount of RCU-related
processing to be done.

Alex Shi's analysis determined that this slowdown is due to lock
contention within the scheduler.  Unfortunately, as Peter Zijlstra points
out, the scheduler's real-time semantics require global action, which
means that this contention is inherent in real-time scheduling.  (Yes,
perhaps someone will come up with a workaround -- otherwise, -rt is not
going to do well on large SMP systems -- but this patch will work around
this issue in the meantime.  And "the meantime" might well be forever.)

This patch therefore re-introduces softirq processing to RCU, but only
for core RCU work.  RCU callbacks are still executed in kthread context,
so that only a small amount of RCU work runs in softirq context in the
common case.  This should minimize ksoftirqd execution, allowing us to
skip boosting of ksoftirqd for CONFIG_RCU_BOOST=y kernels.

Signed-off-by: Shaohua Li &lt;shaohua.li@intel.com&gt;
Tested-by: "Alex,Shi" &lt;alex.shi@intel.com&gt;
Signed-off-by: Paul E. McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Commit a26ac2455ffcf3(rcu: move TREE_RCU from softirq to kthread)
introduced performance regression. In an AIM7 test, this commit degraded
performance by about 40%.

The commit runs rcu callbacks in a kthread instead of softirq. We observed
high rate of context switch which is caused by this. Out test system has
64 CPUs and HZ is 1000, so we saw more than 64k context switch per second
which is caused by RCU's per-CPU kthread.  A trace showed that most of
the time the RCU per-CPU kthread doesn't actually handle any callbacks,
but instead just does a very small amount of work handling grace periods.
This means that RCU's per-CPU kthreads are making the scheduler do quite
a bit of work in order to allow a very small amount of RCU-related
processing to be done.

Alex Shi's analysis determined that this slowdown is due to lock
contention within the scheduler.  Unfortunately, as Peter Zijlstra points
out, the scheduler's real-time semantics require global action, which
means that this contention is inherent in real-time scheduling.  (Yes,
perhaps someone will come up with a workaround -- otherwise, -rt is not
going to do well on large SMP systems -- but this patch will work around
this issue in the meantime.  And "the meantime" might well be forever.)

This patch therefore re-introduces softirq processing to RCU, but only
for core RCU work.  RCU callbacks are still executed in kthread context,
so that only a small amount of RCU work runs in softirq context in the
common case.  This should minimize ksoftirqd execution, allowing us to
skip boosting of ksoftirqd for CONFIG_RCU_BOOST=y kernels.

Signed-off-by: Shaohua Li &lt;shaohua.li@intel.com&gt;
Tested-by: "Alex,Shi" &lt;alex.shi@intel.com&gt;
Signed-off-by: Paul E. McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6</title>
<updated>2011-06-09T23:27:42+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2011-06-09T23:27:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6aecceccf5aa626b0af203e54ca62cbf308c53d8'/>
<id>6aecceccf5aa626b0af203e54ca62cbf308c53d8</id>
<content type='text'>
* 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
  perf: Use make kernelversion instead of parsing the Makefile
  kbuild: Hack for depmod not handling X.Y versions
  kbuild: Move depmod call to a separate script
  kbuild: Fix &lt;linux/version.h&gt; for empty SUBLEVEL or PATCHLEVEL
  kbuild: Fix KERNELVERSION for empty SUBLEVEL or PATCHLEVEL
  kbuild: silence Nothing to be done for 'all' message
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
* 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
  perf: Use make kernelversion instead of parsing the Makefile
  kbuild: Hack for depmod not handling X.Y versions
  kbuild: Move depmod call to a separate script
  kbuild: Fix &lt;linux/version.h&gt; for empty SUBLEVEL or PATCHLEVEL
  kbuild: Fix KERNELVERSION for empty SUBLEVEL or PATCHLEVEL
  kbuild: silence Nothing to be done for 'all' message
</pre>
</div>
</content>
</entry>
<entry>
<title>perf: Use make kernelversion instead of parsing the Makefile</title>
<updated>2011-06-09T21:05:54+00:00</updated>
<author>
<name>Michal Marek</name>
<email>mmarek@suse.cz</email>
</author>
<published>2011-05-30T12:12:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5d61b9fd19d9f3cf653dbba615876e7792eea5ea'/>
<id>5d61b9fd19d9f3cf653dbba615876e7792eea5ea</id>
<content type='text'>
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Ingo Molnar &lt;mingo@elte.hu&gt;
Cc: Arnaldo Carvalho de Melo &lt;acme@ghostprotocols.net&gt;
Signed-off-by: Michal Marek &lt;mmarek@suse.cz&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Paul Mackerras &lt;paulus@samba.org&gt;
Cc: Ingo Molnar &lt;mingo@elte.hu&gt;
Cc: Arnaldo Carvalho de Melo &lt;acme@ghostprotocols.net&gt;
Signed-off-by: Michal Marek &lt;mmarek@suse.cz&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf python: Fix argument name list of read_on_cpu()</title>
<updated>2011-06-03T13:09:22+00:00</updated>
<author>
<name>Frederic Weisbecker</name>
<email>fweisbec@gmail.com</email>
</author>
<published>2011-03-31T16:27:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b273fa9716aa1564bee88ceee62f9042981cdc81'/>
<id>b273fa9716aa1564bee88ceee62f9042981cdc81</id>
<content type='text'>
Mandatory arguments need to be present in the argument name list, as
well as optional arguments, otherwise python barfs:

	# ./python/twatch.py
	Traceback (most recent call last):
	  File "./python/twatch.py", line 41, in &lt;module&gt;
	    main()
	  File "./python/twatch.py", line 32, in main
	    event = evlist.read_on_cpu(cpu)
	RuntimeError: more argument specifiers than keyword list entries

Hence, add cpu to the name list.

Cc: David Ahern &lt;daahern@cisco.com&gt;
Cc: Ingo Molnar &lt;mingo@elte.hu&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;
Cc: Tom Zanussi &lt;tzanussi@gmail.com&gt;
Link: http://lkml.kernel.org/r/1301588863-20210-1-git-send-email-fweisbec@gmail.com
Signed-off-by: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
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>
Mandatory arguments need to be present in the argument name list, as
well as optional arguments, otherwise python barfs:

	# ./python/twatch.py
	Traceback (most recent call last):
	  File "./python/twatch.py", line 41, in &lt;module&gt;
	    main()
	  File "./python/twatch.py", line 32, in main
	    event = evlist.read_on_cpu(cpu)
	RuntimeError: more argument specifiers than keyword list entries

Hence, add cpu to the name list.

Cc: David Ahern &lt;daahern@cisco.com&gt;
Cc: Ingo Molnar &lt;mingo@elte.hu&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;
Cc: Tom Zanussi &lt;tzanussi@gmail.com&gt;
Link: http://lkml.kernel.org/r/1301588863-20210-1-git-send-email-fweisbec@gmail.com
Signed-off-by: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
