On Mon, 2014-04-14 at 09:32 -0700, Paul E. McKenney wrote: > On Mon, Apr 14, 2014 at 12:19:31PM -0400, Pranith Kumar wrote: > > Hi Paul, > > > > On Mon, Apr 14, 2014 at 12:07 PM, Paul E. McKenney > > <paul...@linux.vnet.ibm.com> wrote: > > > On Sun, Apr 13, 2014 at 05:53:53PM -0400, Pranith Kumar wrote: > > >> remove duplicate definition of extern resched_cpu > > >> > > >> Signed-off-by: Pranith Kumar <bobby.pr...@gmail.com> > > > > > > Hello, Pranith, > > > > > > When I apply this patch I get the following: > > > > > > /home/paulmck/public_git/linux-rcu/kernel/rcu/tree.c: In function > > > ‘rcu_implicit_dynticks_qs’: > > > /home/paulmck/public_git/linux-rcu/kernel/rcu/tree.c:895:3: error: > > > implicit declaration of function ‘resched_cpu’ > > > [-Werror=implicit-function-declaration] > > > /home/paulmck/public_git/linux-rcu/kernel/rcu/tree.c: At top level: > > > /home/paulmck/public_git/linux-rcu/kernel/rcu/tree.c:1009:13: warning: > > > conflicting types for ‘resched_cpu’ [enabled by default] > > > /home/paulmck/public_git/linux-rcu/kernel/rcu/tree.c:895:3: note: > > > previous implicit declaration of ‘resched_cpu’ was here > > > > > > This failed in under number of different Kconfig setups, the .config file > > > for one of them is attached. > > > > > > So this declaration really is needed. Just out of curiosity, what led > > > you to believe that it could be removed? > > > > > > > That is strange. The patch removes a duplicate declaration of > > resched_cpu (on lines 768, 954) of the file kernel/rcu/tree.c of the > > latest git. > > > > The patch compiles fine here with the latest tip of the git tree. > > > > CC kernel/rcu/tree.o > > > > Can you please check if your tree.c has two declarations for resched_cpu? > > Ah, your patch didn't apply, so I hand-applied it, and removed the first > declaration rather than the second one. Trying it again.
Perhaps this might be better than using the extern. This also would allow the resched_cpu call to become static inline as it's very small. --- kernel/rcu/tree.c | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 0c47e30..7f2c8c2 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -60,6 +60,13 @@ #include "tree.h" #include "rcu.h" +/* + * This include of sched.h (for resched_cpu) really isn't for public + * consumption, but RCU is special in that context switches can allow + * the state machine to make progress. + */ +#include "../sched/sched.h" + MODULE_ALIAS("rcutree"); #ifdef MODULE_PARAM_PREFIX #undef MODULE_PARAM_PREFIX @@ -762,12 +769,6 @@ static int dyntick_save_progress_counter(struct rcu_data *rdp, } /* - * This function really isn't for public consumption, but RCU is special in - * that context switches can allow the state machine to make progress. - */ -extern void resched_cpu(int cpu); - -/* * Return true if the specified CPU has passed through a quiescent * state by virtue of being in or having passed through an dynticks * idle state since the last call to dyntick_save_progress_counter() @@ -947,12 +948,6 @@ static void print_other_cpu_stall(struct rcu_state *rsp) force_quiescent_state(rsp); /* Kick them all. */ } -/* - * This function really isn't for public consumption, but RCU is special in - * that context switches can allow the state machine to make progress. - */ -extern void resched_cpu(int cpu); - static void print_cpu_stall(struct rcu_state *rsp) { int cpu; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/