<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux/kernel/trace/ring_buffer_benchmark.c, branch v4.3</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=v4.3</id>
<link rel='self' href='https://git.shady.money/linux/atom?h=v4.3'/>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/'/>
<updated>2015-06-26T21:02:43Z</updated>
<entry>
<title>Merge tag 'trace-v4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace</title>
<updated>2015-06-26T21:02:43Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2015-06-26T21:02:43Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=e382608254e06c8109f40044f5e693f2e04f3899'/>
<id>urn:sha1:e382608254e06c8109f40044f5e693f2e04f3899</id>
<content type='text'>
Pull tracing updates from Steven Rostedt:
 "This patch series contains several clean ups and even a new trace
  clock "monitonic raw".  Also some enhancements to make the ring buffer
  even faster.  But the biggest and most noticeable change is the
  renaming of the ftrace* files, structures and variables that have to
  deal with trace events.

  Over the years I've had several developers tell me about their
  confusion with what ftrace is compared to events.  Technically,
  "ftrace" is the infrastructure to do the function hooks, which include
  tracing and also helps with live kernel patching.  But the trace
  events are a separate entity altogether, and the files that affect the
  trace events should not be named "ftrace".  These include:

    include/trace/ftrace.h         -&gt;    include/trace/trace_events.h
    include/linux/ftrace_event.h   -&gt;    include/linux/trace_events.h

  Also, functions that are specific for trace events have also been renamed:

    ftrace_print_*()               -&gt;    trace_print_*()
    (un)register_ftrace_event()    -&gt;    (un)register_trace_event()
    ftrace_event_name()            -&gt;    trace_event_name()
    ftrace_trigger_soft_disabled() -&gt;    trace_trigger_soft_disabled()
    ftrace_define_fields_##call()  -&gt;    trace_define_fields_##call()
    ftrace_get_offsets_##call()    -&gt;    trace_get_offsets_##call()

  Structures have been renamed:

    ftrace_event_file              -&gt;    trace_event_file
    ftrace_event_{call,class}      -&gt;    trace_event_{call,class}
    ftrace_event_buffer            -&gt;    trace_event_buffer
    ftrace_subsystem_dir           -&gt;    trace_subsystem_dir
    ftrace_event_raw_##call        -&gt;    trace_event_raw_##call
    ftrace_event_data_offset_##call-&gt;    trace_event_data_offset_##call
    ftrace_event_type_funcs_##call -&gt;    trace_event_type_funcs_##call

  And a few various variables and flags have also been updated.

  This has been sitting in linux-next for some time, and I have not
  heard a single complaint about this rename breaking anything.  Mostly
  because these functions, variables and structures are mostly internal
  to the tracing system and are seldom (if ever) used by anything
  external to that"

* tag 'trace-v4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (33 commits)
  ring_buffer: Allow to exit the ring buffer benchmark immediately
  ring-buffer-benchmark: Fix the wrong type
  ring-buffer-benchmark: Fix the wrong param in module_param
  ring-buffer: Add enum names for the context levels
  ring-buffer: Remove useless unused tracing_off_permanent()
  ring-buffer: Give NMIs a chance to lock the reader_lock
  ring-buffer: Add trace_recursive checks to ring_buffer_write()
  ring-buffer: Allways do the trace_recursive checks
  ring-buffer: Move recursive check to per_cpu descriptor
  ring-buffer: Add unlikelys to make fast path the default
  tracing: Rename ftrace_get_offsets_##call() to trace_event_get_offsets_##call()
  tracing: Rename ftrace_define_fields_##call() to trace_event_define_fields_##call()
  tracing: Rename ftrace_event_type_funcs_##call to trace_event_type_funcs_##call
  tracing: Rename ftrace_data_offset_##call to trace_event_data_offset_##call
  tracing: Rename ftrace_raw_##call event structures to trace_event_raw_##call
  tracing: Rename ftrace_trigger_soft_disabled() to trace_trigger_soft_disabled()
  tracing: Rename FTRACE_EVENT_FL_* flags to EVENT_FILE_FL_*
  tracing: Rename struct ftrace_subsystem_dir to trace_subsystem_dir
  tracing: Rename ftrace_event_name() to trace_event_name()
  tracing: Rename FTRACE_MAX_EVENT to TRACE_EVENT_TYPE_MAX
  ...
</content>
</entry>
<entry>
<title>ring_buffer: Allow to exit the ring buffer benchmark immediately</title>
<updated>2015-06-15T16:03:12Z</updated>
<author>
<name>Petr Mladek</name>
<email>pmladek@suse.cz</email>
</author>
<published>2015-06-15T13:53:10Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=b44754d8262d3aab842998cf747f44fe6090be9f'/>
<id>urn:sha1:b44754d8262d3aab842998cf747f44fe6090be9f</id>
<content type='text'>
It takes a while until the ring_buffer_benchmark module is removed
when the ring buffer hammer is running. It is because it takes
few seconds and kthread_should_stop() is not being checked.

This patch adds the check for kthread termination into the producer.
It uses the existing @kill_test flag to finish the kthreads as
cleanly as possible.

It disables printing the "ERROR" message when the kthread is going.

It makes sure that producer does not go into the 10sec sleep
when it is being killed.

Finally, it does not call wait_to_die() when kthread_should_stop()
already returns true.

Link: http://lkml.kernel.org/r/20150615155428.GD3135@pathway.suse.cz

Signed-off-by: Petr Mladek &lt;pmladek@suse.cz&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>ring-buffer-benchmark: Fix the wrong sched_priority of producer</title>
<updated>2015-06-11T13:27:58Z</updated>
<author>
<name>Wang Long</name>
<email>long.wanglong@huawei.com</email>
</author>
<published>2015-06-10T08:12:37Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=108029323910c5dd1ef8fa2d10da1ce5fbce6e12'/>
<id>urn:sha1:108029323910c5dd1ef8fa2d10da1ce5fbce6e12</id>
<content type='text'>
The producer should be used producer_fifo as its sched_priority,
so correct it.

Link: http://lkml.kernel.org/r/1433923957-67842-1-git-send-email-long.wanglong@huawei.com

Cc: stable@vger.kernel.org # 2.6.33+
Signed-off-by: Wang Long &lt;long.wanglong@huawei.com&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>ring-buffer-benchmark: Fix the wrong type</title>
<updated>2015-06-10T19:45:22Z</updated>
<author>
<name>Wang Long</name>
<email>long.wanglong@huawei.com</email>
</author>
<published>2015-06-10T08:12:07Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=33d657d1381025542b84b79d5c7b548598e40a4d'/>
<id>urn:sha1:33d657d1381025542b84b79d5c7b548598e40a4d</id>
<content type='text'>
The macro 'module_param' shows that the type of the
variable disable_reader and write_iteration is unsigned
integer. so, we change their type form int to unsigned int.

Link: http://lkml.kernel.org/r/1433923927-67782-1-git-send-email-long.wanglong@huawei.com

Signed-off-by: Wang Long &lt;long.wanglong@huawei.com&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>ring-buffer-benchmark: Fix the wrong param in module_param</title>
<updated>2015-06-10T19:44:35Z</updated>
<author>
<name>Wang Long</name>
<email>long.wanglong@huawei.com</email>
</author>
<published>2015-06-10T08:11:13Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=7364e86547bc52a555c9317b32cc4e81c4d4fd7c'/>
<id>urn:sha1:7364e86547bc52a555c9317b32cc4e81c4d4fd7c</id>
<content type='text'>
The {producer|consumer}_{nice|fifo} parameters are integer
type, we should use 'int' as the second param in module_param.

For example(consumer_fifo):
	the default value of consumer_fifo is -1.
   Without this patch:
        # cat /sys/module/ring_buffer_benchmark/parameters/consumer_fifo
        4294967295
   With this patch:
	# cat /sys/module/ring_buffer_benchmark/parameters/consumer_fifo
	-1

Link: http://lkml.kernel.org/r/1433923873-67712-1-git-send-email-long.wanglong@huawei.com

Signed-off-by: Wang Long &lt;long.wanglong@huawei.com&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>trace: Use 64-bit timekeeping</title>
<updated>2015-01-28T16:02:05Z</updated>
<author>
<name>Tina Ruchandani</name>
<email>ruchandani.tina@gmail.com</email>
</author>
<published>2015-01-28T14:16:11Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=da194930ede6d87945786f72b1c36c7a4ed0f3a6'/>
<id>urn:sha1:da194930ede6d87945786f72b1c36c7a4ed0f3a6</id>
<content type='text'>
The ring_buffer_producer uses 'struct timeval' to measure
its start and end times. 'struct timeval' on 32-bit systems
will have its tv_sec value overflow in year 2038 and beyond.
This patch replaces struct timeval with 'ktime_t' which uses
64-bit representation for nanoseconds.

Link: http://lkml.kernel.org/r/20150128141611.GA2701@tinar

Suggested-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Suggested-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Signed-off-by: Tina Ruchandani &lt;ruchandani.tina@gmail.com&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>sched, cleanup, treewide: Remove set_current_state(TASK_RUNNING) after schedule()</title>
<updated>2014-09-19T10:35:17Z</updated>
<author>
<name>Kirill Tkhai</name>
<email>ktkhai@parallels.com</email>
</author>
<published>2014-09-12T13:40:54Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=f139caf2e89713687514d9db847a4fa2e29c87a2'/>
<id>urn:sha1:f139caf2e89713687514d9db847a4fa2e29c87a2</id>
<content type='text'>
schedule(), io_schedule() and schedule_timeout() always return
with TASK_RUNNING state set, so one more setting is unnecessary.

(All places in patch are visible good, only exception is
 kiblnd_scheduler() from:

      drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd_cb.c

 Its schedule() is one line above standard 3 lines of unified diff)

No places where set_current_state() is used for mb().

Signed-off-by: Kirill Tkhai &lt;ktkhai@parallels.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Link: http://lkml.kernel.org/r/1410529254.3569.23.camel@tkhai
Cc: Alasdair Kergon &lt;agk@redhat.com&gt;
Cc: Anil Belur &lt;askb23@gmail.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Dave Kleikamp &lt;shaggy@kernel.org&gt;
Cc: David Airlie &lt;airlied@linux.ie&gt;
Cc: David Howells &lt;dhowells@redhat.com&gt;
Cc: Dmitry Eremin &lt;dmitry.eremin@intel.com&gt;
Cc: Frank Blaschka &lt;blaschka@linux.vnet.ibm.com&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Helge Deller &lt;deller@gmx.de&gt;
Cc: Isaac Huang &lt;he.huang@intel.com&gt;
Cc: James E.J. Bottomley &lt;JBottomley@parallels.com&gt;
Cc: James E.J. Bottomley &lt;jejb@parisc-linux.org&gt;
Cc: J. Bruce Fields &lt;bfields@fieldses.org&gt;
Cc: Jeff Dike &lt;jdike@addtoit.com&gt;
Cc: Jesper Nilsson &lt;jesper.nilsson@axis.com&gt;
Cc: Jiri Slaby &lt;jslaby@suse.cz&gt;
Cc: Laura Abbott &lt;lauraa@codeaurora.org&gt;
Cc: Liang Zhen &lt;liang.zhen@intel.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Cc: Masaru Nomura &lt;massa.nomura@gmail.com&gt;
Cc: Michael Opdenacker &lt;michael.opdenacker@free-electrons.com&gt;
Cc: Mikael Starvik &lt;starvik@axis.com&gt;
Cc: Mike Snitzer &lt;snitzer@redhat.com&gt;
Cc: Neil Brown &lt;neilb@suse.de&gt;
Cc: Oleg Drokin &lt;green@linuxhacker.ru&gt;
Cc: Peng Tao &lt;bergwolf@gmail.com&gt;
Cc: Richard Weinberger &lt;richard@nod.at&gt;
Cc: Robert Love &lt;robert.w.love@intel.com&gt;
Cc: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Trond Myklebust &lt;trond.myklebust@primarydata.com&gt;
Cc: Ursula Braun &lt;ursula.braun@de.ibm.com&gt;
Cc: Zi Shen Lim &lt;zlim.lnx@gmail.com&gt;
Cc: devel@driverdev.osuosl.org
Cc: dm-devel@redhat.com
Cc: dri-devel@lists.freedesktop.org
Cc: fcoe-devel@open-fcoe.org
Cc: jfs-discussion@lists.sourceforge.net
Cc: linux390@de.ibm.com
Cc: linux-afs@lists.infradead.org
Cc: linux-cris-kernel@axis.com
Cc: linux-kernel@vger.kernel.org
Cc: linux-nfs@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linux-raid@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linux-scsi@vger.kernel.org
Cc: qla2xxx-upstream@qlogic.com
Cc: user-mode-linux-devel@lists.sourceforge.net
Cc: user-mode-linux-user@lists.sourceforge.net
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
</entry>
<entry>
<title>trace: Replace hardcoding of 19 with MAX_NICE</title>
<updated>2014-02-27T11:41:03Z</updated>
<author>
<name>Dongsheng Yang</name>
<email>yangds.fnst@cn.fujitsu.com</email>
</author>
<published>2014-02-24T14:12:01Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=2b3942e4bb20ef8ef26515bd958c2df83d9a6210'/>
<id>urn:sha1:2b3942e4bb20ef8ef26515bd958c2df83d9a6210</id>
<content type='text'>
Use MAX_NICE instead of the value 19 for ring_buffer_benchmark.

Signed-off-by: Dongsheng Yang &lt;yangds.fnst@cn.fujitsu.com&gt;
Signed-off-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Acked-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Link: http://lkml.kernel.org/r/1393251121-25534-1-git-send-email-yangds.fnst@cn.fujitsu.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
</entry>
<entry>
<title>tracing: Use NUMA allocation for per-cpu ring buffer pages</title>
<updated>2011-06-15T02:04:39Z</updated>
<author>
<name>Vaibhav Nagarnaik</name>
<email>vnagarnaik@google.com</email>
</author>
<published>2011-05-04T00:56:42Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=7ea5906405a1f3fc1c0033dfd7e02f2cfd1de5e5'/>
<id>urn:sha1:7ea5906405a1f3fc1c0033dfd7e02f2cfd1de5e5</id>
<content type='text'>
The tracing ring buffer is a group of per-cpu ring buffers where
allocation and logging is done on a per-cpu basis. The events that are
generated on a particular CPU are logged in the corresponding buffer.
This is to provide wait-free writes between CPUs and good NUMA node
locality while accessing the ring buffer.

However, the allocation routines consider NUMA locality only for buffer
page metadata and not for the actual buffer page. This causes the pages
to be allocated on the NUMA node local to the CPU where the allocation
routine is running at the time.

This patch fixes the problem by using a NUMA node specific allocation
routine so that the pages are allocated from a NUMA node local to the
logging CPU.

I tested with the getuid_microbench from autotest. It is a simple binary
that calls getuid() in a loop and measures the average time for the
syscall to complete. The following command was used to test:
$ getuid_microbench 1000000

Compared the numbers found on kernel with and without this patch and
found that logging latency decreases by 30-50 ns/call.
tracing with non-NUMA allocation - 569 ns/call
tracing with NUMA allocation     - 512 ns/call

Signed-off-by: Vaibhav Nagarnaik &lt;vnagarnaik@google.com&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Michael Rubin &lt;mrubin@google.com&gt;
Cc: David Sharp &lt;dhsharp@google.com&gt;
Link: http://lkml.kernel.org/r/1304470602-20366-1-git-send-email-vnagarnaik@google.com
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>ring-buffer: Make benchmark handle missed events</title>
<updated>2010-04-27T17:26:58Z</updated>
<author>
<name>Steven Rostedt</name>
<email>srostedt@redhat.com</email>
</author>
<published>2010-04-27T17:26:58Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=a838b2e634405fb89ddbf4fa9412acb33911911f'/>
<id>urn:sha1:a838b2e634405fb89ddbf4fa9412acb33911911f</id>
<content type='text'>
With the addition of the "missed events" flags that is stored in the
commit field of the ring buffer page, the ring_buffer_benchmark
was not updated to handle this. If events are missed, then the
missed events flag is set in the ring buffer page, the benchmark
will count that flag as part of the size of the page and will hit the BUG()
when it tries to read beyond the page.

The solution is simply to have the ring buffer benchmark mask off
the extra bits.

Reported-by: Ingo Molnar &lt;mingo@elte.hu&gt;
Signed-off-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
</content>
</entry>
</feed>
