On 2019-09-11 17:57:25 [+0100], Scott Wood wrote: > index 388ace315f32..9ce7c5006a5e 100644 > --- a/include/linux/rcupdate.h > +++ b/include/linux/rcupdate.h > @@ -600,6 +600,36 @@ static inline void rcu_read_unlock(void) > rcu_lock_release(&rcu_lock_map); /* Keep acq info for rls diags. */ > } > > +#ifdef CONFIG_PREEMPT_RT_FULL > +/* > + * On RT, local_bh_disable() calls rcu_read_lock() -- no need to > + * track it twice. > + */ > +static inline void rcu_bh_lock_acquire(void) > +{ > +} > + > +static inline void rcu_bh_lock_release(void) > +{ > +} > +#else > +static inline void rcu_bh_lock_acquire(void) > +{ > + __acquire(RCU_BH); > + rcu_lock_acquire(&rcu_bh_lock_map); > + RCU_LOCKDEP_WARN(!rcu_is_watching(), > + "rcu_read_lock_bh() used illegally while idle"); > +} > + > +static inline void rcu_bh_lock_release(void) > +{ > + RCU_LOCKDEP_WARN(!rcu_is_watching(), > + "rcu_read_unlock_bh() used illegally while idle"); > + rcu_lock_release(&rcu_bh_lock_map); > + __release(RCU_BH); > +} > +#endif > + > /** > * rcu_read_lock_bh() - mark the beginning of an RCU-bh critical section > * > @@ -615,10 +645,7 @@ static inline void rcu_read_unlock(void) > static inline void rcu_read_lock_bh(void) > { > local_bh_disable(); > - __acquire(RCU_BH); > - rcu_lock_acquire(&rcu_bh_lock_map); > - RCU_LOCKDEP_WARN(!rcu_is_watching(), > - "rcu_read_lock_bh() used illegally while idle"); > + rcu_bh_lock_acquire(); > } > > /*
I asked previously why do you need to change rcu_read_lock_bh() and you replied that you don't remember: https://lore.kernel.org/linux-rt-users/b948ec6cccda31925ed8dc123bd0f55423fff3d4.ca...@redhat.com/ Did this change? Sebastian