On Tue, Jul 16, 2019 at 11:26:42AM -0700, Paul E. McKenney wrote: > On Fri, Jul 12, 2019 at 01:00:18PM -0400, Joel Fernandes (Google) wrote: > > The rcu/sync code was doing its own check whether we are in a reader > > section. With RCU consolidating flavors and the generic helper added in > > this series, this is no longer need. We can just use the generic helper > > and it results in a nice cleanup. > > > > Cc: Oleg Nesterov <oleg@xxxxxxxxxx> > > Signed-off-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx> > > This needs to be forward-ported to current mainline. (Or, I believe > equivalently for this file, to branch "dev" of -rcu.) > > Especially given that you have Oleg's Ack, I would be happy to > take the forward-ported version. Never mind, I am one version behind. Apologies for the noise! Thanx, Paul > > --- > > Please note: Only build and boot tested this particular patch so far. > > > > include/linux/rcu_sync.h | 5 ++--- > > kernel/rcu/sync.c | 22 ---------------------- > > 2 files changed, 2 insertions(+), 25 deletions(-) > > > > diff --git a/include/linux/rcu_sync.h b/include/linux/rcu_sync.h > > index 6fc53a1345b3..c954f1efc919 100644 > > --- a/include/linux/rcu_sync.h > > +++ b/include/linux/rcu_sync.h > > @@ -39,9 +39,8 @@ extern void rcu_sync_lockdep_assert(struct rcu_sync *); > > */ > > static inline bool rcu_sync_is_idle(struct rcu_sync *rsp) > > { > > -#ifdef CONFIG_PROVE_RCU > > - rcu_sync_lockdep_assert(rsp); > > -#endif > > + RCU_LOCKDEP_WARN(!rcu_read_lock_any_held(), > > + "suspicious rcu_sync_is_idle() usage"); > > return !rsp->gp_state; /* GP_IDLE */ > > } > > > > diff --git a/kernel/rcu/sync.c b/kernel/rcu/sync.c > > index a8304d90573f..535e02601f56 100644 > > --- a/kernel/rcu/sync.c > > +++ b/kernel/rcu/sync.c > > @@ -10,37 +10,25 @@ > > #include <linux/rcu_sync.h> > > #include <linux/sched.h> > > > > -#ifdef CONFIG_PROVE_RCU > > -#define __INIT_HELD(func) .held = func, > > -#else > > -#define __INIT_HELD(func) > > -#endif > > - > > 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 > > } gp_ops[] = { > > [RCU_SYNC] = { > > .sync = synchronize_rcu, > > .call = call_rcu, > > .wait = rcu_barrier, > > - __INIT_HELD(rcu_read_lock_held) > > }, > > [RCU_SCHED_SYNC] = { > > .sync = synchronize_rcu, > > .call = call_rcu, > > .wait = rcu_barrier, > > - __INIT_HELD(rcu_read_lock_sched_held) > > }, > > [RCU_BH_SYNC] = { > > .sync = synchronize_rcu, > > .call = call_rcu, > > .wait = rcu_barrier, > > - __INIT_HELD(rcu_read_lock_bh_held) > > }, > > }; > > > > @@ -49,16 +37,6 @@ enum { CB_IDLE = 0, CB_PENDING, CB_REPLAY }; > > > > #define rss_lock gp_wait.lock > > > > -#ifdef CONFIG_PROVE_RCU > > -void rcu_sync_lockdep_assert(struct rcu_sync *rsp) > > -{ > > - RCU_LOCKDEP_WARN(!gp_ops[rsp->gp_type].held(), > > - "suspicious rcu_sync_is_idle() usage"); > > -} > > - > > -EXPORT_SYMBOL_GPL(rcu_sync_lockdep_assert); > > -#endif > > - > > /** > > * rcu_sync_init() - Initialize an rcu_sync structure > > * @rsp: Pointer to rcu_sync structure to be initialized > > -- > > 2.22.0.510.g264f2c817a-goog > >