<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/tools/perf/builtin-report.c, branch v4.4.88</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>perf symbols: Allow forcing reading of non-root owned files by root</title>
<updated>2015-11-12T21:58:18+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2015-11-12T19:50:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=2059fc7a5a9e667797b8ec503bfb4685afee48d8'/>
<id>2059fc7a5a9e667797b8ec503bfb4685afee48d8</id>
<content type='text'>
When the root user tries to read a file owned by some other user we get:

  # ls -la perf.data
  -rw-------. 1 acme acme 20032 Nov 12 15:50 perf.data
  # perf report
  File perf.data not owned by current user or root (use -f to override)
  # perf report -f | grep -v ^# | head -2
    30.96%  ls       [kernel.vmlinux]  [k] do_set_pte
    28.24%  ls       libc-2.20.so      [.] intel_check_word
  #

That wasn't happening when the symbol code tried to read a JIT map,
where the same check was done but no forcing was possible, fix it.

Reported-by: Brendan Gregg &lt;brendan.d.gregg@gmail.com&gt;
Tested-by: Brendan Gregg &lt;brendan.d.gregg@gmail.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: http://permalink.gmane.org/gmane.linux.kernel.perf.user/2380
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 the root user tries to read a file owned by some other user we get:

  # ls -la perf.data
  -rw-------. 1 acme acme 20032 Nov 12 15:50 perf.data
  # perf report
  File perf.data not owned by current user or root (use -f to override)
  # perf report -f | grep -v ^# | head -2
    30.96%  ls       [kernel.vmlinux]  [k] do_set_pte
    28.24%  ls       libc-2.20.so      [.] intel_check_word
  #

That wasn't happening when the symbol code tried to read a JIT map,
where the same check was done but no forcing was possible, fix it.

Reported-by: Brendan Gregg &lt;brendan.d.gregg@gmail.com&gt;
Tested-by: Brendan Gregg &lt;brendan.d.gregg@gmail.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: http://permalink.gmane.org/gmane.linux.kernel.perf.user/2380
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf report: Rename to --show-cpu-utilization</title>
<updated>2015-10-26T17:06:04+00:00</updated>
<author>
<name>Namhyung Kim</name>
<email>namhyung@kernel.org</email>
</author>
<published>2015-10-24T15:49:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=b272a59d835cd8ca6b45f41c66c61b473996c759'/>
<id>b272a59d835cd8ca6b45f41c66c61b473996c759</id>
<content type='text'>
So that it can be more consistent with other --show-* options.  The old
name (--showcpuutilization) is provided only for compatibility.

Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: David Ahern &lt;dsahern@gmail.com&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/1445701767-12731-2-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>
So that it can be more consistent with other --show-* options.  The old
name (--showcpuutilization) is provided only for compatibility.

Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: David Ahern &lt;dsahern@gmail.com&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/1445701767-12731-2-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 tools: Improve call graph documents and help messages</title>
<updated>2015-10-22T19:23:19+00:00</updated>
<author>
<name>Namhyung Kim</name>
<email>namhyung@kernel.org</email>
</author>
<published>2015-10-22T14:28:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=76a26549eb367f683fbb394b7246bef5dc665f8c'/>
<id>76a26549eb367f683fbb394b7246bef5dc665f8c</id>
<content type='text'>
The --call-graph option is complex so we should provide better guide for
users.  Also change help message to be consistent with config option
names.  Now perf top will show help like below:

  $ perf top --call-graph
    Error: option `call-graph' requires a value

   Usage: perf top [&lt;options&gt;]

      --call-graph &lt;record_mode[,record_size],print_type,threshold[,print_limit],order,sort_key[,branch]&gt;
           setup and enables call-graph (stack chain/backtrace):

		record_mode:	call graph recording mode (fp|dwarf|lbr)
		record_size:	if record_mode is 'dwarf', max size of stack recording (&lt;bytes&gt;)
				default: 8192 (bytes)
		print_type:	call graph printing style (graph|flat|fractal|none)
		threshold:	minimum call graph inclusion threshold (&lt;percent&gt;)
		print_limit:	maximum number of call graph entry (&lt;number&gt;)
		order:		call graph order (caller|callee)
		sort_key:	call graph sort key (function|address)
		branch:		include last branch info to call graph (branch)

		Default: fp,graph,0.5,caller,function

Requested-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Acked-by: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Brendan Gregg &lt;brendan.d.gregg@gmail.com&gt;
Cc: Chandler Carruth &lt;chandlerc@gmail.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: http://lkml.kernel.org/r/1445524112-5201-2-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>
The --call-graph option is complex so we should provide better guide for
users.  Also change help message to be consistent with config option
names.  Now perf top will show help like below:

  $ perf top --call-graph
    Error: option `call-graph' requires a value

   Usage: perf top [&lt;options&gt;]

      --call-graph &lt;record_mode[,record_size],print_type,threshold[,print_limit],order,sort_key[,branch]&gt;
           setup and enables call-graph (stack chain/backtrace):

		record_mode:	call graph recording mode (fp|dwarf|lbr)
		record_size:	if record_mode is 'dwarf', max size of stack recording (&lt;bytes&gt;)
				default: 8192 (bytes)
		print_type:	call graph printing style (graph|flat|fractal|none)
		threshold:	minimum call graph inclusion threshold (&lt;percent&gt;)
		print_limit:	maximum number of call graph entry (&lt;number&gt;)
		order:		call graph order (caller|callee)
		sort_key:	call graph sort key (function|address)
		branch:		include last branch info to call graph (branch)

		Default: fp,graph,0.5,caller,function

Requested-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Acked-by: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Brendan Gregg &lt;brendan.d.gregg@gmail.com&gt;
Cc: Chandler Carruth &lt;chandlerc@gmail.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: http://lkml.kernel.org/r/1445524112-5201-2-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 tools: Defaults to 'caller' callchain order only if --children is enabled</title>
<updated>2015-10-22T18:40:11+00:00</updated>
<author>
<name>Namhyung Kim</name>
<email>namhyung@kernel.org</email>
</author>
<published>2015-10-22T07:45:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=792aeafa8ed08e5e18fb66ab93b470f78e619f75'/>
<id>792aeafa8ed08e5e18fb66ab93b470f78e619f75</id>
<content type='text'>
The caller callchain order is useful with --children option since it can
show 'overview' style output, but other commands which don't use
--children feature like 'perf script' or even 'perf report/top' without
--children are better to keep callee order.

Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Acked-by: Brendan Gregg &lt;brendan.d.gregg@gmail.com&gt;
Acked-by: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Acked-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Chandler Carruth &lt;chandlerc@gmail.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: http://lkml.kernel.org/r/1445499946-29817-1-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>
The caller callchain order is useful with --children option since it can
show 'overview' style output, but other commands which don't use
--children feature like 'perf script' or even 'perf report/top' without
--children are better to keep callee order.

Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Acked-by: Brendan Gregg &lt;brendan.d.gregg@gmail.com&gt;
Acked-by: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Acked-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Chandler Carruth &lt;chandlerc@gmail.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: http://lkml.kernel.org/r/1445499946-29817-1-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 tools: Move callchain help messages to callchain.h</title>
<updated>2015-10-22T18:39:51+00:00</updated>
<author>
<name>Namhyung Kim</name>
<email>namhyung@kernel.org</email>
</author>
<published>2015-10-22T06:28:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=21cf62847d29392e51c37460856d3c3c57769c5e'/>
<id>21cf62847d29392e51c37460856d3c3c57769c5e</id>
<content type='text'>
These messages will be used by 'perf top' in the next patch.

Signed-off-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: Brendan Gregg &lt;brendan.d.gregg@gmail.com&gt;
Cc: Chandler Carruth &lt;chandlerc@gmail.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: http://lkml.kernel.org/r/1445495330-25416-1-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>
These messages will be used by 'perf top' in the next patch.

Signed-off-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: Brendan Gregg &lt;brendan.d.gregg@gmail.com&gt;
Cc: Chandler Carruth &lt;chandlerc@gmail.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: http://lkml.kernel.org/r/1445495330-25416-1-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 callchain: Switch default to 'graph,0.5,caller'</title>
<updated>2015-10-05T20:59:43+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2015-10-05T20:05:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=def02db0d662b0edd83f80e3c18f660fc414decb'/>
<id>def02db0d662b0edd83f80e3c18f660fc414decb</id>
<content type='text'>
Which is the most common default found in other similar tools.

Requested-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Chandler Carruth &lt;chandlerc@gmail.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: https://www.youtube.com/watch?v=nXaxk27zwlk
Link: http://lkml.kernel.org/n/tip-v8lq36aispvdwgxdmt9p9jd9@git.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>
Which is the most common default found in other similar tools.

Requested-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Chandler Carruth &lt;chandlerc@gmail.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: https://www.youtube.com/watch?v=nXaxk27zwlk
Link: http://lkml.kernel.org/n/tip-v8lq36aispvdwgxdmt9p9jd9@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf machine: Add method for common kernel_map(FUNCTION) operation</title>
<updated>2015-09-30T21:34:29+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2015-09-30T14:54:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=a5e813c68649366aaa3f785772b00ea6ccad7b8d'/>
<id>a5e813c68649366aaa3f785772b00ea6ccad7b8d</id>
<content type='text'>
And it is also a step in the direction of killing the separation of data
and text maps in map_groups.

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: http://lkml.kernel.org/n/tip-rrds86kb3wx5wk8v38v56gw8@git.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>
And it is also a step in the direction of killing the separation of data
and text maps in map_groups.

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: http://lkml.kernel.org/n/tip-rrds86kb3wx5wk8v38v56gw8@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf machine: Use machine__kernel_map() thoroughly</title>
<updated>2015-09-30T21:34:28+00:00</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2015-09-30T14:08:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=77e65977495cd6f6fcfacd8c16bdd9c8c18a1d72'/>
<id>77e65977495cd6f6fcfacd8c16bdd9c8c18a1d72</id>
<content type='text'>
In places where we were using its open coded equivalent.

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: http://lkml.kernel.org/n/tip-khkdugcdoqy3tkszm3jdxgbe@git.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>
In places where we were using its open coded equivalent.

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Link: http://lkml.kernel.org/n/tip-khkdugcdoqy3tkszm3jdxgbe@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf report: Make max_stack value allow for synthesized callchains</title>
<updated>2015-09-28T20:03:20+00:00</updated>
<author>
<name>Adrian Hunter</name>
<email>adrian.hunter@intel.com</email>
</author>
<published>2015-09-25T13:15:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=188bb5e2ce112463428994f91291e5df6fc05521'/>
<id>188bb5e2ce112463428994f91291e5df6fc05521</id>
<content type='text'>
perf report has an option (--max-stack) to set the maximum stack depth
when processing callchains.  The option defaults to the hard-coded
maximum definition PERF_MAX_STACK_DEPTH which is 127.  The intention of
the option is to allow the user to reduce the processing time by
reducing the amount of the callchain that is processed.

It is also possible, when processing instruction traces, to synthesize
callchains.  Synthesized callchains do not have the kernel size
limitation and are whatever size the user requests, although validation
presently prevents the user requested a value greater that 1024.  The
default value is 16.

To allow for synthesized callchains, make the max_stack value at least
the same size as the synthesized callchain size.

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/1443186956-18718-16-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
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<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
perf report has an option (--max-stack) to set the maximum stack depth
when processing callchains.  The option defaults to the hard-coded
maximum definition PERF_MAX_STACK_DEPTH which is 127.  The intention of
the option is to allow the user to reduce the processing time by
reducing the amount of the callchain that is processed.

It is also possible, when processing instruction traces, to synthesize
callchains.  Synthesized callchains do not have the kernel size
limitation and are whatever size the user requests, although validation
presently prevents the user requested a value greater that 1024.  The
default value is 16.

To allow for synthesized callchains, make the max_stack value at least
the same size as the synthesized callchain size.

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/1443186956-18718-16-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf report: Skip events with null branch stacks</title>
<updated>2015-09-28T19:57:01+00:00</updated>
<author>
<name>Adrian Hunter</name>
<email>adrian.hunter@intel.com</email>
</author>
<published>2015-09-25T13:15:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=f86225db3aa0e394915af45eea1c3cca6f3e2dba'/>
<id>f86225db3aa0e394915af45eea1c3cca6f3e2dba</id>
<content type='text'>
A non-synthesized event might not have a branch stack if branch stacks
have been synthesized (using itrace options).

An example of that is when Intel PT records sched_switch events for
decoding purposes.  Those sched_switch events do not have branch stacks
even though the Intel PT decoder may be synthesizing other events that
do due to the itrace options.

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/1443186956-18718-12-git-send-email-adrian.hunter@intel.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>
A non-synthesized event might not have a branch stack if branch stacks
have been synthesized (using itrace options).

An example of that is when Intel PT records sched_switch events for
decoding purposes.  Those sched_switch events do not have branch stacks
even though the Intel PT decoder may be synthesizing other events that
do due to the itrace options.

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/1443186956-18718-12-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</pre>
</div>
</content>
</entry>
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