On Fri, Sep 11, 2026 at 10:18:04PM +0100, Bradley Morgan wrote: > On 11 September 2026 17:09:13 BST, Kunwu Chan <[email protected]> wrote: > >Add the RCU_LOCKDEP_WARN and early-boot check that the Tree version > >gained, srcu_lock_sync() was already present. > > > >Suggested-by: Zqiang <[email protected]> > > Ok. > > Reviewed-by: Bradley Morgan <[email protected]>
Applied, thank you! > >Signed-off-by: Kunwu Chan <[email protected]> > >--- > > kernel/rcu/srcutiny.c | 6 ++++++ > > 1 file changed, 6 insertions(+) > > > >diff --git a/kernel/rcu/srcutiny.c b/kernel/rcu/srcutiny.c > >index 99f8bfd98b04..76411562366f 100644 > >--- a/kernel/rcu/srcutiny.c > >+++ b/kernel/rcu/srcutiny.c > >@@ -361,6 +361,12 @@ void synchronize_srcu_atomic(struct srcu_struct *ssp) > > > > srcu_lock_sync(&ssp->dep_map); > > > >+ RCU_LOCKDEP_WARN(lockdep_is_held(ssp), > >+ "Illegal synchronize_srcu_atomic() in same-type SRCU > >read-side critical section"); > >+ > >+ if (rcu_scheduler_active == RCU_SCHEDULER_INACTIVE) > >+ return; > >+ > > Wow! If you think that this one is fun, take a look at the implementation of synchronize_rcu() in kernel/rcu/tiny.c. ;-) Thanx, Paul > > if (IS_ENABLED(CONFIG_PREEMPTION)) > > synchronize_rcu(); // Needed for RCU Tasks Trace to imply RCU > > grace period. > > // And in Tiny RCU, it is near zero cost and > > doesn't block. > > > > --- Thanks! > https://lore.kernel.org/all/[email protected]/
