<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux/kernel/trace/trace_functions_graph.c, branch v3.16</title>
<subtitle>Mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/
</subtitle>
<id>https://git.shady.money/linux/atom?h=v3.16</id>
<link rel='self' href='https://git.shady.money/linux/atom?h=v3.16'/>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/'/>
<updated>2014-05-21T03:29:32Z</updated>
<entry>
<title>tracing: Add funcgraph_tail option to print function name after closing braces</title>
<updated>2014-05-21T03:29:32Z</updated>
<author>
<name>Robert Elliott</name>
<email>elliott@hp.com</email>
</author>
<published>2014-05-20T22:10:51Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=607e3a29203633eaec7334f2f58f9653df788a06'/>
<id>urn:sha1:607e3a29203633eaec7334f2f58f9653df788a06</id>
<content type='text'>
In the function-graph tracer, add a funcgraph_tail option
to print the function name on all } lines, not just
functions whose first line is no longer in the trace
buffer.

If a function calls other traced functions, its total
time appears on its } line.  This change allows grep
to be used to determine the function for which the
line corresponds.

Update Documentation/trace/ftrace.txt to describe
this new option.

Link: http://lkml.kernel.org/p/20140520221041.8359.6782.stgit@beardog.cce.hp.com

Signed-off-by: Robert Elliott &lt;elliott@hp.com&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>tracing: Eliminate duplicate TRACE_GRAPH_PRINT_xx defines</title>
<updated>2014-05-21T03:28:34Z</updated>
<author>
<name>Robert Elliott</name>
<email>elliott@hp.com</email>
</author>
<published>2014-05-20T22:10:36Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=ccdb594653b1c0d5b0f3e6f8bf764c544ba0606d'/>
<id>urn:sha1:ccdb594653b1c0d5b0f3e6f8bf764c544ba0606d</id>
<content type='text'>
Eliminate duplicate TRACE_GRAPH_PRINT_xx defines
in trace_functions_graph.c that are already in
trace.h.

Add TRACE_GRAPH_PRINT_IRQS to trace.h, which is
the only one that is missing.

Link: http://lkml.kernel.org/p/20140520221031.8359.24733.stgit@beardog.cce.hp.com

Signed-off-by: Robert Elliott &lt;elliott@hp.com&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>tracing: Remove mock up poll wait function</title>
<updated>2014-04-30T12:40:05Z</updated>
<author>
<name>Steven Rostedt (Red Hat)</name>
<email>rostedt@goodmis.org</email>
</author>
<published>2014-04-29T21:54:37Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=b1169cc69ba96b124df820904a6d3eb775491d7f'/>
<id>urn:sha1:b1169cc69ba96b124df820904a6d3eb775491d7f</id>
<content type='text'>
Now that the ring buffer has a built in way to wake up readers
when there's data, using irq_work such that it is safe to do it
in any context. But it was still using the old "poor man's"
wait polling that checks every 1/10 of a second to see if it
should wake up a waiter. This makes the latency for a wake up
excruciatingly long. No need to do that anymore.

Completely remove the different wait_poll types from the tracers
and have them all use the default one now.

Reported-by: Johannes Berg &lt;johannes@sipsolutions.net&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>tracing: Pass trace_array to set_flag callback</title>
<updated>2014-02-20T17:13:07Z</updated>
<author>
<name>Steven Rostedt (Red Hat)</name>
<email>rostedt@goodmis.org</email>
</author>
<published>2014-01-10T16:13:54Z</published>
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<id>urn:sha1:8c1a49aedb73fb2f15aaa32ad9e2e1c4289f45cb</id>
<content type='text'>
As options (flags) may affect instances instead of being global
the set_flag() callbacks need to receive the trace_array descriptor
of the instance they will be modifying.

Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>tracing: Do not use signed enums with unsigned long long in fgragh output</title>
<updated>2013-11-06T20:26:56Z</updated>
<author>
<name>Steven Rostedt (Red Hat)</name>
<email>rostedt@goodmis.org</email>
</author>
<published>2013-11-06T19:50:06Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=6fc84ea70eae478099c866ace022ecfdef998032'/>
<id>urn:sha1:6fc84ea70eae478099c866ace022ecfdef998032</id>
<content type='text'>
The duration field of print_graph_duration() can also be used
to do the space filling by passing an enum in it:

  DURATION_FILL_FULL
  DURATION_FILL_START
  DURATION_FILL_END

The problem is that these are enums and defined as negative,
but the duration field is unsigned long long. Most archs are
fine with this but blackfin fails to compile because of it:

kernel/built-in.o: In function `print_graph_duration':
kernel/trace/trace_functions_graph.c:782: undefined reference to `__ucmpdi2'

Overloading a unsigned long long with an signed enum is just
bad in principle. We can accomplish the same thing by using
part of the flags field instead.

Cc: Mike Frysinger &lt;vapier@gentoo.org&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>tracing: Update event filters for multibuffer</title>
<updated>2013-11-05T21:50:20Z</updated>
<author>
<name>Tom Zanussi</name>
<email>tom.zanussi@linux.intel.com</email>
</author>
<published>2013-10-24T13:34:17Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=f306cc82a93d6b19f01634b80c580b9755c8b7cc'/>
<id>urn:sha1:f306cc82a93d6b19f01634b80c580b9755c8b7cc</id>
<content type='text'>
The trace event filters are still tied to event calls rather than
event files, which means you don't get what you'd expect when using
filters in the multibuffer case:

Before:

  # echo 'bytes_alloc &gt; 8192' &gt; /sys/kernel/debug/tracing/events/kmem/kmalloc/filter
  # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/filter
  bytes_alloc &gt; 8192
  # mkdir /sys/kernel/debug/tracing/instances/test1
  # echo 'bytes_alloc &gt; 2048' &gt; /sys/kernel/debug/tracing/instances/test1/events/kmem/kmalloc/filter
  # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/filter
  bytes_alloc &gt; 2048
  # cat /sys/kernel/debug/tracing/instances/test1/events/kmem/kmalloc/filter
  bytes_alloc &gt; 2048

Setting the filter in tracing/instances/test1/events shouldn't affect
the same event in tracing/events as it does above.

After:

  # echo 'bytes_alloc &gt; 8192' &gt; /sys/kernel/debug/tracing/events/kmem/kmalloc/filter
  # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/filter
  bytes_alloc &gt; 8192
  # mkdir /sys/kernel/debug/tracing/instances/test1
  # echo 'bytes_alloc &gt; 2048' &gt; /sys/kernel/debug/tracing/instances/test1/events/kmem/kmalloc/filter
  # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/filter
  bytes_alloc &gt; 8192
  # cat /sys/kernel/debug/tracing/instances/test1/events/kmem/kmalloc/filter
  bytes_alloc &gt; 2048

We'd like to just move the filter directly from ftrace_event_call to
ftrace_event_file, but there are a couple cases that don't yet have
multibuffer support and therefore have to continue using the current
event_call-based filters.  For those cases, a new USE_CALL_FILTER bit
is added to the event_call flags, whose main purpose is to keep the
old behavior for those cases until they can be updated with
multibuffer support; at that point, the USE_CALL_FILTER flag (and the
new associated call_filter_check_discard() function) can go away.

The multibuffer support also made filter_current_check_discard()
redundant, so this change removes that function as well and replaces
it with filter_check_discard() (or call_filter_check_discard() as
appropriate).

Link: http://lkml.kernel.org/r/f16e9ce4270c62f46b2e966119225e1c3cca7e60.1382620672.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi &lt;tom.zanussi@linux.intel.com&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>ftrace: Add set_graph_notrace filter</title>
<updated>2013-10-19T02:23:16Z</updated>
<author>
<name>Namhyung Kim</name>
<email>namhyung.kim@lge.com</email>
</author>
<published>2013-10-14T08:24:26Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=29ad23b00474c34e3b5040dda508c78d33a1a3eb'/>
<id>urn:sha1:29ad23b00474c34e3b5040dda508c78d33a1a3eb</id>
<content type='text'>
The set_graph_notrace filter is analogous to set_ftrace_notrace and
can be used for eliminating uninteresting part of function graph trace
output.  It also works with set_graph_function nicely.

  # cd /sys/kernel/debug/tracing/
  # echo do_page_fault &gt; set_graph_function
  # perf ftrace live true
   2)               |  do_page_fault() {
   2)               |    __do_page_fault() {
   2)   0.381 us    |      down_read_trylock();
   2)   0.055 us    |      __might_sleep();
   2)   0.696 us    |      find_vma();
   2)               |      handle_mm_fault() {
   2)               |        handle_pte_fault() {
   2)               |          __do_fault() {
   2)               |            filemap_fault() {
   2)               |              find_get_page() {
   2)   0.033 us    |                __rcu_read_lock();
   2)   0.035 us    |                __rcu_read_unlock();
   2)   1.696 us    |              }
   2)   0.031 us    |              __might_sleep();
   2)   2.831 us    |            }
   2)               |            _raw_spin_lock() {
   2)   0.046 us    |              add_preempt_count();
   2)   0.841 us    |            }
   2)   0.033 us    |            page_add_file_rmap();
   2)               |            _raw_spin_unlock() {
   2)   0.057 us    |              sub_preempt_count();
   2)   0.568 us    |            }
   2)               |            unlock_page() {
   2)   0.084 us    |              page_waitqueue();
   2)   0.126 us    |              __wake_up_bit();
   2)   1.117 us    |            }
   2)   7.729 us    |          }
   2)   8.397 us    |        }
   2)   8.956 us    |      }
   2)   0.085 us    |      up_read();
   2) + 12.745 us   |    }
   2) + 13.401 us   |  }
  ...

  # echo handle_mm_fault &gt; set_graph_notrace
  # perf ftrace live true
   1)               |  do_page_fault() {
   1)               |    __do_page_fault() {
   1)   0.205 us    |      down_read_trylock();
   1)   0.041 us    |      __might_sleep();
   1)   0.344 us    |      find_vma();
   1)   0.069 us    |      up_read();
   1)   4.692 us    |    }
   1)   5.311 us    |  }
  ...

Link: http://lkml.kernel.org/r/1381739066-7531-5-git-send-email-namhyung@kernel.org

Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>tracing: Add ref_data to function and fgraph tracer structs</title>
<updated>2013-07-19T01:31:31Z</updated>
<author>
<name>Steven Rostedt (Red Hat)</name>
<email>rostedt@goodmis.org</email>
</author>
<published>2013-07-18T18:41:51Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=8f768993394a8c0d3801033c11fd86ce8c88dcac'/>
<id>urn:sha1:8f768993394a8c0d3801033c11fd86ce8c88dcac</id>
<content type='text'>
The selftest for function and function graph tracers are defined as
__init, as they are only executed at boot up. The "tracer" structs
that are associated to those tracers are not setup as __init as they
are used after boot. To stop mismatch warnings, those structures
need to be annotated with __ref_data.

Currently, the tracer structures are defined to __read_mostly, as they
do not really change. But in the future they should be converted to
consts, but that will take a little work because they have a "next"
pointer that gets updated when they are registered. That will have to
wait till the next major release.

Link: http://lkml.kernel.org/r/1373596735.17876.84.camel@gandalf.local.home

Reported-by: kbuild test robot &lt;fengguang.wu@intel.com&gt;
Reported-by: Chen Gang &lt;gang.chen@asianux.com&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>tracing: Use trace_seq_puts()/trace_seq_putc() where possible</title>
<updated>2013-07-19T01:30:36Z</updated>
<author>
<name>zhangwei(Jovi)</name>
<email>jovi.zhangwei@huawei.com</email>
</author>
<published>2013-07-15T08:32:44Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=146c3442f2dd0f50d9431aea5d0d10dfd97c9999'/>
<id>urn:sha1:146c3442f2dd0f50d9431aea5d0d10dfd97c9999</id>
<content type='text'>
For string without format specifiers, use trace_seq_puts()
or trace_seq_putc().

Link: http://lkml.kernel.org/r/51E3B3AC.1000605@huawei.com

Signed-off-by: zhangwei(Jovi) &lt;jovi.zhangwei@huawei.com&gt;
[ fixed a trace_seq_putc(s, " ") to trace_seq_putc(s, ' ') ]
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>tracing: Consolidate max_tr into main trace_array structure</title>
<updated>2013-03-15T04:35:40Z</updated>
<author>
<name>Steven Rostedt (Red Hat)</name>
<email>srostedt@redhat.com</email>
</author>
<published>2013-03-05T14:24:35Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=12883efb670c28dff57dcd7f4f995a1ffe153b2d'/>
<id>urn:sha1:12883efb670c28dff57dcd7f4f995a1ffe153b2d</id>
<content type='text'>
Currently, the way the latency tracers and snapshot feature works
is to have a separate trace_array called "max_tr" that holds the
snapshot buffer. For latency tracers, this snapshot buffer is used
to swap the running buffer with this buffer to save the current max
latency.

The only items needed for the max_tr is really just a copy of the buffer
itself, the per_cpu data pointers, the time_start timestamp that states
when the max latency was triggered, and the cpu that the max latency
was triggered on. All other fields in trace_array are unused by the
max_tr, making the max_tr mostly bloat.

This change removes the max_tr completely, and adds a new structure
called trace_buffer, that holds the buffer pointer, the per_cpu data
pointers, the time_start timestamp, and the cpu where the latency occurred.

The trace_array, now has two trace_buffers, one for the normal trace and
one for the max trace or snapshot. By doing this, not only do we remove
the bloat from the max_trace but the instances of traces can now use
their own snapshot feature and not have just the top level global_trace have
the snapshot feature and latency tracers for itself.

Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
</entry>
</feed>
