On Tue, Oct 08, 2013 at 12:25:11PM +0200, Peter Zijlstra wrote: > From: Oleg Nesterov <o...@redhat.com> > > Add the new rcu_sync_ops->wait() method and the new helper, > rcu_sync_dtor(). > > It is needed if you are going to, say, kfree(rcu_sync_object). > It simply calls ops->wait() to "flush" the potentially pending > rcu callback. > > Signed-off-by: Oleg Nesterov <o...@redhat.com> > Signed-off-by: Peter Zijlstra <pet...@infradead.org>
Reviewed-by: Paul E. McKenney <paul...@linux.vnet.ibm.com> > Link: http://lkml.kernel.org/r/20131004184636.ga17...@redhat.com > --- > include/linux/rcusync.h | 1 + > kernel/rcusync.c | 22 ++++++++++++++++++++++ > 2 files changed, 23 insertions(+) > > --- a/include/linux/rcusync.h > +++ b/include/linux/rcusync.h > @@ -31,6 +31,7 @@ static inline bool rcu_sync_is_idle(stru > extern void rcu_sync_init(struct rcu_sync_struct *, enum rcu_sync_type); > extern void rcu_sync_enter(struct rcu_sync_struct *); > extern void rcu_sync_exit(struct rcu_sync_struct *); > +extern void rcu_sync_dtor(struct rcu_sync_struct *); > > #define __RCU_SYNC_INITIALIZER(name, type) { \ > .gp_state = 0, \ > --- a/kernel/rcusync.c > +++ b/kernel/rcusync.c > @@ -10,6 +10,7 @@ > static const struct { > void (*sync)(void); > void (*call)(struct rcu_head *, void (*)(struct rcu_head *)); > + void (*wait)(void); > #ifdef CONFIG_PROVE_RCU > int (*held)(void); > #endif > @@ -17,16 +18,19 @@ static const struct { > [RCU_SYNC] = { > .sync = synchronize_rcu, > .call = call_rcu, > + .wait = rcu_barrier, > __INIT_HELD(rcu_read_lock_held) > }, > [RCU_SCHED_SYNC] = { > .sync = synchronize_sched, > .call = call_rcu_sched, > + .wait = rcu_barrier_sched, > __INIT_HELD(rcu_read_lock_sched_held) > }, > [RCU_BH_SYNC] = { > .sync = synchronize_rcu_bh, > .call = call_rcu_bh, > + .wait = rcu_barrier_bh, > __INIT_HELD(rcu_read_lock_bh_held) > }, > }; > @@ -128,3 +132,21 @@ void rcu_sync_exit(struct rcu_sync_struc > } > spin_unlock_irq(&rss->rss_lock); > } > + > +void rcu_sync_dtor(struct rcu_sync_struct *rss) > +{ > + int cb_state; > + > + BUG_ON(rss->gp_count); > + > + spin_lock_irq(&rss->rss_lock); > + if (rss->cb_state == CB_REPLAY) > + rss->cb_state = CB_PENDING; > + cb_state = rss->cb_state; > + spin_unlock_irq(&rss->rss_lock); > + > + if (cb_state != CB_IDLE) { > + gp_ops[rss->gp_type].wait(); > + BUG_ON(rss->cb_state != CB_IDLE); > + } > +} > > -- 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/
