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[for-next][PATCH 01/13] tracepoints: Fix documentation of RCU lockdep checks

From Steven Rostedt <rostedt@goodmis.org>
Newsgroups linux.kernel
Subject [for-next][PATCH 01/13] tracepoints: Fix documentation of RCU lockdep checks
Date 2015-11-04 16:40 +0100
Message-ID <qr8kk-2go-87@gated-at.bofh.it> (permalink)
References <qr8kh-2go-3@gated-at.bofh.it>
Organization linux.* mail to news gateway

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From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

The documentation on top of __DECLARE_TRACE() does not match its
implementation since the condition check has been added to the
RCU lockdep checks. Update the documentation to match its
implementation.

Link: http://lkml.kernel.org/r/1446504164-21563-1-git-send-email-mathieu.desnoyers@efficios.com

CC: Dave Hansen <dave@sr71.net>
Fixes: a05d59a56733 "tracing: Add condition check to RCU lockdep checks"
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 include/linux/tracepoint.h | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
index 6b79537a42b1..696a339c592c 100644
--- a/include/linux/tracepoint.h
+++ b/include/linux/tracepoint.h
@@ -184,10 +184,11 @@ extern void syscall_unregfunc(void);
  * structure. Force alignment to the same alignment as the section start.
  *
  * When lockdep is enabled, we make sure to always do the RCU portions of
- * the tracepoint code, regardless of whether tracing is on or we match the
- * condition.  This lets us find RCU issues triggered with tracepoints even
- * when this tracepoint is off.  This code has no purpose other than poking
- * RCU a bit.
+ * the tracepoint code, regardless of whether tracing is on. However,
+ * don't check if the condition is false, due to interaction with idle
+ * instrumentation. This lets us find RCU issues triggered with tracepoints
+ * even when this tracepoint is off. This code has no purpose other than
+ * poking RCU a bit.
  */
 #define __DECLARE_TRACE(name, proto, args, cond, data_proto, data_args) \
 	extern struct tracepoint __tracepoint_##name;			\
-- 
2.6.1


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Thread

[for-next][PATCH 00/13] tracing: Some more last minute cleanups and fixes for 4.4 Steven Rostedt <rostedt@goodmis.org> - 2015-11-04 16:40 +0100
  [for-next][PATCH 13/13] tracing: Put back comma for empty fields in boot string parsing Steven Rostedt <rostedt@goodmis.org> - 2015-11-04 16:40 +0100
  [for-next][PATCH 05/13] tracing: Rename max_stack_lock to stack_trace_max_lock Steven Rostedt <rostedt@goodmis.org> - 2015-11-04 16:40 +0100
  [for-next][PATCH 12/13] tracing: Apply tracer specific options from kernel command line. Steven Rostedt <rostedt@goodmis.org> - 2015-11-04 16:40 +0100
  [for-next][PATCH 09/13] tracing: Allow dumping traces without tracking trace started cpus Steven Rostedt <rostedt@goodmis.org> - 2015-11-04 16:40 +0100
  [for-next][PATCH 02/13] recordmcount: Fix endianness handling bug for nop_mcount Steven Rostedt <rostedt@goodmis.org> - 2015-11-04 16:40 +0100
  [for-next][PATCH 07/13] ring_buffer: Do no not complete benchmark reader too early Steven Rostedt <rostedt@goodmis.org> - 2015-11-04 16:40 +0100
  [for-next][PATCH 06/13] tracing: Remove redundant TP_ARGS redefining Steven Rostedt <rostedt@goodmis.org> - 2015-11-04 16:40 +0100
  [for-next][PATCH 08/13] ring_buffer: Fix more races when terminating the producer in the  benchmark Steven Rostedt <rostedt@goodmis.org> - 2015-11-04 16:40 +0100
  [for-next][PATCH 10/13] ring_buffer: Remove unneeded smp_wmb() before wakeup of reader  benchmark Steven Rostedt <rostedt@goodmis.org> - 2015-11-04 16:40 +0100
  [for-next][PATCH 04/13] tracing: Allow arch-specific stack tracer Steven Rostedt <rostedt@goodmis.org> - 2015-11-04 16:40 +0100
  [for-next][PATCH 03/13] recordmcount: arm64: Replace the ignored mcount call into nop Steven Rostedt <rostedt@goodmis.org> - 2015-11-04 16:40 +0100
  [for-next][PATCH 01/13] tracepoints: Fix documentation of RCU lockdep checks Steven Rostedt <rostedt@goodmis.org> - 2015-11-04 16:40 +0100

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