Messages in this thread | | | Date | Mon, 24 Aug 2009 19:25:32 -0700 | From | "Paul E. McKenney" <> | Subject | Re: [PATCH -tip 1/2] Add "notrace" to RCU function headers used by ftrace. |
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On Mon, Aug 24, 2009 at 10:11:40PM -0400, Steven Rostedt wrote: > > On Mon, 24 Aug 2009, Paul E. McKenney wrote: > > > On Mon, Aug 24, 2009 at 07:38:51PM -0400, Steven Rostedt wrote: > > > > > > On Mon, 24 Aug 2009, Paul E. McKenney wrote: > > > > > > > Both rcu_read_lock_sched_notrace() and rcu_read_unlock_sched_notrace() > > > > are used by ftrace, and thus need to be marked "notrace". Unfortunately, > > > > my naive assumption that gcc would see the inner "notrace" does not hold. > > > > Kudos to Lai Jiangshan for noting this. > > > > > > > > Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> > > > > --- > > > > include/linux/rcupdate.h | 4 ++-- > > > > 1 files changed, 2 insertions(+), 2 deletions(-) > > > > > > > > diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h > > > > index ec90fc3..8b4422c 100644 > > > > --- a/include/linux/rcupdate.h > > > > +++ b/include/linux/rcupdate.h > > > > @@ -191,7 +191,7 @@ static inline void rcu_read_lock_sched(void) > > > > __acquire(RCU_SCHED); > > > > rcu_read_acquire(); > > > > } > > > > -static inline void rcu_read_lock_sched_notrace(void) > > > > +static inline notrace void rcu_read_lock_sched_notrace(void) > > > > { > > > > preempt_disable_notrace(); > > > > __acquire(RCU_SCHED); > > > > @@ -209,7 +209,7 @@ static inline void rcu_read_unlock_sched(void) > > > > __release(RCU_SCHED); > > > > preempt_enable(); > > > > } > > > > -static inline void rcu_read_unlock_sched_notrace(void) > > > > +static inline notrace void rcu_read_unlock_sched_notrace(void) > > > > > > Funny, inlines should not be traced. Is gcc ignoring the inlines here? > > > > Well, that was my line of thinking as well, until Lai Jiangshan set > > me straight. Version 4.x of gcc apparently decides on a case-by-case > > basis. > > Yeah, I've seen gcc do it, but when it does it to static inlines in header > files, I just get a feeling to squinge.
Especially when they are as short and simple as those particular functions were...
Thanx, Paul
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