<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/kernel/trace/Kconfig, branch v5.10.38</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.10.38</id>
<link rel='self' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.10.38'/>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/'/>
<updated>2021-01-19T17:27:19Z</updated>
<entry>
<title>tracing/kprobes: Do the notrace functions check without kprobes on ftrace</title>
<updated>2021-01-19T17:27:19Z</updated>
<author>
<name>Masami Hiramatsu</name>
<email>mhiramat@kernel.org</email>
</author>
<published>2021-01-08T04:19:38Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=75942370699b15e93ea97749467801a1683e9076'/>
<id>urn:sha1:75942370699b15e93ea97749467801a1683e9076</id>
<content type='text'>
commit 7bb83f6fc4ee84e95d0ac0d14452c2619fb3fe70 upstream.

Enable the notrace function check on the architecture which doesn't
support kprobes on ftrace but support dynamic ftrace. This notrace
function check is not only for the kprobes on ftrace but also
sw-breakpoint based kprobes.
Thus there is no reason to limit this check for the arch which
supports kprobes on ftrace.

This also changes the dependency of Kconfig. Because kprobe event
uses the function tracer's address list for identifying notrace
function, if the CONFIG_DYNAMIC_FTRACE=n, it can not check whether
the target function is notrace or not.

Link: https://lkml.kernel.org/r/20210105065730.2634785-1-naveen.n.rao@linux.vnet.ibm.com
Link: https://lkml.kernel.org/r/161007957862.114704.4512260007555399463.stgit@devnote2

Cc: stable@vger.kernel.org
Fixes: 45408c4f92506 ("tracing: kprobes: Prohibit probing on notrace function")
Acked-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>ftrace: Fix DYNAMIC_FTRACE_WITH_DIRECT_CALLS dependency</title>
<updated>2020-12-01T02:43:08Z</updated>
<author>
<name>Naveen N. Rao</name>
<email>naveen.n.rao@linux.vnet.ibm.com</email>
</author>
<published>2020-11-26T18:08:39Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=49a962c075dfa41c78e34784772329bc8784d217'/>
<id>urn:sha1:49a962c075dfa41c78e34784772329bc8784d217</id>
<content type='text'>
DYNAMIC_FTRACE_WITH_DIRECT_CALLS should depend on
DYNAMIC_FTRACE_WITH_REGS since we need ftrace_regs_caller().

Link: https://lkml.kernel.org/r/fc4b257ea8689a36f086d2389a9ed989496ca63a.1606412433.git.naveen.n.rao@linux.vnet.ibm.com

Cc: stable@vger.kernel.org
Fixes: 763e34e74bb7d5c ("ftrace: Add register_ftrace_direct()")
Signed-off-by: Naveen N. Rao &lt;naveen.n.rao@linux.vnet.ibm.com&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'trace-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace</title>
<updated>2020-06-09T17:06:18Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-06-09T17:06:18Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=d1e521adad250ab8c979861c857fa2b1542c9741'/>
<id>urn:sha1:d1e521adad250ab8c979861c857fa2b1542c9741</id>
<content type='text'>
Pull tracing updates from Steven Rostedt:
 "No new features this release. Mostly clean ups, restructuring and
  documentation.

   - Have ftrace_bug() show ftrace errors before the WARN, as the WARN
     will reboot the box before the error messages are printed if
     panic_on_warn is set.

   - Have traceoff_on_warn disable tracing sooner (before prints)

   - Write a message to the trace buffer that its being disabled when
     disable_trace_on_warning() is set.

   - Separate out synthetic events from histogram code to let it be used
     by other parts of the kernel.

   - More documentation on histogram design.

   - Other small fixes and clean ups"

* tag 'trace-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Remove obsolete PREEMPTIRQ_EVENTS kconfig option
  tracing/doc: Fix ascii-art in histogram-design.rst
  tracing: Add a trace print when traceoff_on_warning is triggered
  ftrace,bug: Improve traceoff_on_warn
  selftests/ftrace: Distinguish between hist and synthetic event checks
  tracing: Move synthetic events to a separate file
  tracing: Fix events.rst section numbering
  tracing/doc: Fix typos in histogram-design.rst
  tracing: Add hist_debug trace event files for histogram debugging
  tracing: Add histogram-design document
  tracing: Check state.disabled in synth event trace functions
  tracing/probe: reverse arguments to list_add
  tools/bootconfig: Add a summary of test cases and return error
  ftrace: show debugging information when panic_on_warn set
</content>
</entry>
<entry>
<title>tracing: Remove obsolete PREEMPTIRQ_EVENTS kconfig option</title>
<updated>2020-06-06T00:08:26Z</updated>
<author>
<name>Mel Gorman</name>
<email>mgorman@techsingularity.net</email>
</author>
<published>2020-04-09T10:40:34Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=388d8bdb87e01bcea6d0b2bf797b5f6d7b2401fb'/>
<id>urn:sha1:388d8bdb87e01bcea6d0b2bf797b5f6d7b2401fb</id>
<content type='text'>
The PREEMPTIRQ_EVENTS option is unused after commit c3bc8fd637a9 ("tracing:
Centralize preemptirq tracepoints and unify their usage"). Remove it.

Note that this option is hazardous as it stands. It enables TRACE_IRQFLAGS
event on non-preempt configurations without the irqsoff tracer enabled.
TRACE_IRQFLAGS as it stands incurs significant overhead on each IRQ
entry/exit. This is because trace_hardirqs_[on|off] does all the per-cpu
manipulations and NMI checks even if tracing is completely disabled for
some insane reason.  For example, netperf running UDP_STREAM on localhost
incurs a 4-6% performance penalty without any tracing if IRQFLAGS is
set. It can be put behind a static brach but even the function entry/exit
costs a little bit.

Link: https://lkml.kernel.org/r/20200409104034.GJ3818@techsingularity.net

Signed-off-by: Mel Gorman &lt;mgorman@techsingularity.net&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>tracing: Move synthetic events to a separate file</title>
<updated>2020-06-01T12:23:22Z</updated>
<author>
<name>Tom Zanussi</name>
<email>zanussi@kernel.org</email>
</author>
<published>2020-05-28T19:32:37Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=726721a51838e3983023f906580722fc83f804ee'/>
<id>urn:sha1:726721a51838e3983023f906580722fc83f804ee</id>
<content type='text'>
With the addition of the in-kernel synthetic event API, synthetic
events are no longer specifically tied to the histogram triggers.

The synthetic event code is also making trace_event_hist.c very
bloated, so for those reasons, move it to a separate file,
trace_events_synth.c, along with a new trace_synth.h header file.

Because synthetic events are now independent from hist triggers, add a
new CONFIG_SYNTH_EVENTS config option, and have CONFIG_HIST_TRIGGERS
select it, and have CONFIG_SYNTH_EVENT_GEN_TEST depend on it.

Link: http://lkml.kernel.org/r/4d1fa1f85ed5982706ac44844ac92451dcb04715.1590693308.git.zanussi@kernel.org

Signed-off-by: Tom Zanussi &lt;zanussi@kernel.org&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>tracing: Add hist_debug trace event files for histogram debugging</title>
<updated>2020-06-01T12:22:30Z</updated>
<author>
<name>Tom Zanussi</name>
<email>zanussi@kernel.org</email>
</author>
<published>2020-04-03T19:31:21Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=2d19bd79ae6509858582a9cade739c2e9a4fdca8'/>
<id>urn:sha1:2d19bd79ae6509858582a9cade739c2e9a4fdca8</id>
<content type='text'>
Add a new "hist_debug" file for each trace event, which when read will
dump out a bunch of internal details about the hist triggers defined
on that event.

This is normally off but can be enabled by saying 'y' to the new
CONFIG_HIST_TRIGGERS_DEBUG config option.

This is in support of the new Documentation file describing histogram
internals, Documentation/trace/histogram-design.rst, which was
requested by developers trying to understand the internals when
extending or making use of the hist triggers for higher-level tools.

The histogram-design.rst documentation refers to the hist_debug files
and demonstrates their use with output in the test examples.

Link: http://lkml.kernel.org/r/77914c22b0ba493d9783c53bbfbc6087d6a7e1b1.1585941485.git.zanussi@kernel.org

Signed-off-by: Tom Zanussi &lt;zanussi@kernel.org&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>sh/ftrace: Move arch_ftrace_nmi_{enter,exit} into nmi exception</title>
<updated>2020-05-19T13:51:18Z</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2020-02-24T21:26:21Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=178ba00c354eb15cec6806a812771e60a5ae3ea1'/>
<id>urn:sha1:178ba00c354eb15cec6806a812771e60a5ae3ea1</id>
<content type='text'>
SuperH is the last remaining user of arch_ftrace_nmi_{enter,exit}(),
remove it from the generic code and into the SuperH code.

Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Alexandre Chartre &lt;alexandre.chartre@oracle.com&gt;
Acked-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Cc: Rich Felker &lt;dalias@libc.org&gt;
Cc: Yoshinori Sato &lt;ysato@users.sourceforge.jp&gt;
Link: https://lkml.kernel.org/r/20200505134101.248881738@linutronix.de


</content>
</entry>
<entry>
<title>Merge tag 'noinstr-lds-2020-05-19' into core/rcu</title>
<updated>2020-05-19T13:50:34Z</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2020-05-19T13:50:34Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=1ed0948eea079a4c802d08cdb2e8db1eee0860f1'/>
<id>urn:sha1:1ed0948eea079a4c802d08cdb2e8db1eee0860f1</id>
<content type='text'>
Get the noinstr section and annotation markers to base the RCU parts on.
</content>
</entry>
<entry>
<title>Stop the ad-hoc games with -Wno-maybe-initialized</title>
<updated>2020-05-09T20:57:10Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-05-09T20:57:10Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=78a5255ffb6a1af189a83e493d916ba1c54d8c75'/>
<id>urn:sha1:78a5255ffb6a1af189a83e493d916ba1c54d8c75</id>
<content type='text'>
We have some rather random rules about when we accept the
"maybe-initialized" warnings, and when we don't.

For example, we consider it unreliable for gcc versions &lt; 4.9, but also
if -O3 is enabled, or if optimizing for size.  And then various kernel
config options disabled it, because they know that they trigger that
warning by confusing gcc sufficiently (ie PROFILE_ALL_BRANCHES).

And now gcc-10 seems to be introducing a lot of those warnings too, so
it falls under the same heading as 4.9 did.

At the same time, we have a very straightforward way to _enable_ that
warning when wanted: use "W=2" to enable more warnings.

So stop playing these ad-hoc games, and just disable that warning by
default, with the known and straight-forward "if you want to work on the
extra compiler warnings, use W=123".

Would it be great to have code that is always so obvious that it never
confuses the compiler whether a variable is used initialized or not?
Yes, it would.  In a perfect world, the compilers would be smarter, and
our source code would be simpler.

That's currently not the world we live in, though.

Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>ftrace: Use synchronize_rcu_tasks_rude() instead of ftrace_sync()</title>
<updated>2020-04-27T18:03:53Z</updated>
<author>
<name>Paul E. McKenney</name>
<email>paulmck@kernel.org</email>
</author>
<published>2020-04-03T19:10:28Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=e5a971d76d701dbff9e5dbaa84dc9e8c3081a867'/>
<id>urn:sha1:e5a971d76d701dbff9e5dbaa84dc9e8c3081a867</id>
<content type='text'>
This commit replaces the schedule_on_each_cpu(ftrace_sync) instances
with synchronize_rcu_tasks_rude().

Suggested-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
[ paulmck: Make Kconfig adjustments noted by kbuild test robot. ]
Signed-off-by: Paul E. McKenney &lt;paulmck@kernel.org&gt;
</content>
</entry>
</feed>
