| Message ID | 20120905062306.GA14756@leaf |
|---|---|
| State | Accepted |
| Commit | 7ece55a4a3a04abe37118b1d4fb0b702eeb1de4c |
| Headers | show |
* Josh Triplett (josh@joshtriplett.org) wrote: > Tracepoints declare a static inline trace_*_rcuidle variant of the trace > function, to support safely generating trace events from the idle loop. > Module code never actually uses that variant of trace functions, because > modules don't run code that needs tracing with RCU idled. However, the > declaration of those otherwise unused functions causes the module to > reference rcu_idle_exit and rcu_idle_enter, which RCU does not export to > modules. > > To avoid this, don't generate trace_*_rcuidle functions for tracepoints > declared in module code. > > Reported-by: Steven Rostedt <rostedt@goodmis.org> > Signed-off-by: Josh Triplett <josh@joshtriplett.org> Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Thanks Josh! Mathieu > --- > On Tue, Sep 04, 2012 at 07:46:42PM -0400, Steven Rostedt wrote: > > We could add either. Probably keep the ugliness of tracepoints inside > > the tracepoint code than to start spreading it around to rcu. RCU has > > its own ugliness features ;-) > > > > Hence, I would be OK if you send me a patch that does what you proposed > > and removes the EXPORT from RCU. > > include/linux/tracepoint.h | 28 ++++++++++++++++++---------- > 1 file changed, 18 insertions(+), 10 deletions(-) > > diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h > index 802de56..2f322c3 100644 > --- a/include/linux/tracepoint.h > +++ b/include/linux/tracepoint.h > @@ -136,6 +136,22 @@ static inline void tracepoint_synchronize_unregister(void) > postrcu; \ > } while (0) > > +#ifndef MODULE > +#define __DECLARE_TRACE_RCU(name, proto, args, cond, data_proto, data_args) \ > + static inline void trace_##name##_rcuidle(proto) \ > + { \ > + if (static_key_false(&__tracepoint_##name.key)) \ > + __DO_TRACE(&__tracepoint_##name, \ > + TP_PROTO(data_proto), \ > + TP_ARGS(data_args), \ > + TP_CONDITION(cond), \ > + rcu_idle_exit(), \ > + rcu_idle_enter()); \ > + } > +#else > +#define __DECLARE_TRACE_RCU(name, proto, args, cond, data_proto, data_args) > +#endif > + > /* > * Make sure the alignment of the structure in the __tracepoints section will > * not add unwanted padding between the beginning of the section and the > @@ -151,16 +167,8 @@ static inline void tracepoint_synchronize_unregister(void) > TP_ARGS(data_args), \ > TP_CONDITION(cond),,); \ > } \ > - static inline void trace_##name##_rcuidle(proto) \ > - { \ > - if (static_key_false(&__tracepoint_##name.key)) \ > - __DO_TRACE(&__tracepoint_##name, \ > - TP_PROTO(data_proto), \ > - TP_ARGS(data_args), \ > - TP_CONDITION(cond), \ > - rcu_idle_exit(), \ > - rcu_idle_enter()); \ > - } \ > + __DECLARE_TRACE_RCU(name, PARAMS(proto), PARAMS(args), \ > + PARAMS(cond), PARAMS(data_proto), PARAMS(data_args)) \ > static inline int \ > register_trace_##name(void (*probe)(data_proto), void *data) \ > { \ > -- > 1.7.10.4 >
On Tue, Sep 04, 2012 at 11:23:06PM -0700, Josh Triplett wrote: > Tracepoints declare a static inline trace_*_rcuidle variant of the trace > function, to support safely generating trace events from the idle loop. > Module code never actually uses that variant of trace functions, because > modules don't run code that needs tracing with RCU idled. However, the > declaration of those otherwise unused functions causes the module to > reference rcu_idle_exit and rcu_idle_enter, which RCU does not export to > modules. > > To avoid this, don't generate trace_*_rcuidle functions for tracepoints > declared in module code. > > Reported-by: Steven Rostedt <rostedt@goodmis.org> > Signed-off-by: Josh Triplett <josh@joshtriplett.org> Looks good to me, please let me know when I should remove the exports. Sending the relevant patch is sufficient notification. ;-) Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Thanx, Paul > --- > On Tue, Sep 04, 2012 at 07:46:42PM -0400, Steven Rostedt wrote: > > We could add either. Probably keep the ugliness of tracepoints inside > > the tracepoint code than to start spreading it around to rcu. RCU has > > its own ugliness features ;-) > > > > Hence, I would be OK if you send me a patch that does what you proposed > > and removes the EXPORT from RCU. > > include/linux/tracepoint.h | 28 ++++++++++++++++++---------- > 1 file changed, 18 insertions(+), 10 deletions(-) > > diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h > index 802de56..2f322c3 100644 > --- a/include/linux/tracepoint.h > +++ b/include/linux/tracepoint.h > @@ -136,6 +136,22 @@ static inline void tracepoint_synchronize_unregister(void) > postrcu; \ > } while (0) > > +#ifndef MODULE > +#define __DECLARE_TRACE_RCU(name, proto, args, cond, data_proto, data_args) \ > + static inline void trace_##name##_rcuidle(proto) \ > + { \ > + if (static_key_false(&__tracepoint_##name.key)) \ > + __DO_TRACE(&__tracepoint_##name, \ > + TP_PROTO(data_proto), \ > + TP_ARGS(data_args), \ > + TP_CONDITION(cond), \ > + rcu_idle_exit(), \ > + rcu_idle_enter()); \ > + } > +#else > +#define __DECLARE_TRACE_RCU(name, proto, args, cond, data_proto, data_args) > +#endif > + > /* > * Make sure the alignment of the structure in the __tracepoints section will > * not add unwanted padding between the beginning of the section and the > @@ -151,16 +167,8 @@ static inline void tracepoint_synchronize_unregister(void) > TP_ARGS(data_args), \ > TP_CONDITION(cond),,); \ > } \ > - static inline void trace_##name##_rcuidle(proto) \ > - { \ > - if (static_key_false(&__tracepoint_##name.key)) \ > - __DO_TRACE(&__tracepoint_##name, \ > - TP_PROTO(data_proto), \ > - TP_ARGS(data_args), \ > - TP_CONDITION(cond), \ > - rcu_idle_exit(), \ > - rcu_idle_enter()); \ > - } \ > + __DECLARE_TRACE_RCU(name, PARAMS(proto), PARAMS(args), \ > + PARAMS(cond), PARAMS(data_proto), PARAMS(data_args)) \ > static inline int \ > register_trace_##name(void (*probe)(data_proto), void *data) \ > { \ > -- > 1.7.10.4 >
On Tue, 2012-09-04 at 23:23 -0700, Josh Triplett wrote: > Tracepoints declare a static inline trace_*_rcuidle variant of the trace > function, to support safely generating trace events from the idle loop. > Module code never actually uses that variant of trace functions, because > modules don't run code that needs tracing with RCU idled. However, the > declaration of those otherwise unused functions causes the module to > reference rcu_idle_exit and rcu_idle_enter, which RCU does not export to > modules. > > To avoid this, don't generate trace_*_rcuidle functions for tracepoints > declared in module code. > > Reported-by: Steven Rostedt <rostedt@goodmis.org> > Signed-off-by: Josh Triplett <josh@joshtriplett.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> -- Steve
diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index 802de56..2f322c3 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -136,6 +136,22 @@ static inline void tracepoint_synchronize_unregister(void) postrcu; \ } while (0) +#ifndef MODULE +#define __DECLARE_TRACE_RCU(name, proto, args, cond, data_proto, data_args) \ + static inline void trace_##name##_rcuidle(proto) \ + { \ + if (static_key_false(&__tracepoint_##name.key)) \ + __DO_TRACE(&__tracepoint_##name, \ + TP_PROTO(data_proto), \ + TP_ARGS(data_args), \ + TP_CONDITION(cond), \ + rcu_idle_exit(), \ + rcu_idle_enter()); \ + } +#else +#define __DECLARE_TRACE_RCU(name, proto, args, cond, data_proto, data_args) +#endif + /* * Make sure the alignment of the structure in the __tracepoints section will * not add unwanted padding between the beginning of the section and the @@ -151,16 +167,8 @@ static inline void tracepoint_synchronize_unregister(void) TP_ARGS(data_args), \ TP_CONDITION(cond),,); \ } \ - static inline void trace_##name##_rcuidle(proto) \ - { \ - if (static_key_false(&__tracepoint_##name.key)) \ - __DO_TRACE(&__tracepoint_##name, \ - TP_PROTO(data_proto), \ - TP_ARGS(data_args), \ - TP_CONDITION(cond), \ - rcu_idle_exit(), \ - rcu_idle_enter()); \ - } \ + __DECLARE_TRACE_RCU(name, PARAMS(proto), PARAMS(args), \ + PARAMS(cond), PARAMS(data_proto), PARAMS(data_args)) \ static inline int \ register_trace_##name(void (*probe)(data_proto), void *data) \ { \