diff options
| author | Paul E. McKenney <paulmck@kernel.org> | 2025-06-03 13:49:53 -0700 |
|---|---|---|
| committer | Neeraj Upadhyay (AMD) <neeraj.upadhyay@kernel.org> | 2025-07-16 09:50:57 +0530 |
| commit | 3aea745a2a82e8397d2f30326f0dcf5f375dd7c8 (patch) | |
| tree | 43a381402b19b806408a175a9743ad41ee2a708e | |
| parent | 941ab0b369c983f7867de54c8579fd7f1676ee3c (diff) | |
srcu: Expedite SRCU-fast grace periods
Currently, SRCU-fast grace periods use synchronize_rcu() to provide the
needed ordering with readers, even given an expedited SRCU-fast grace
period, which isn't all that expedited. This commit therefore instead
uses synchronize_rcu_expedited() if there is an expedited SRCU-fast
grace period in flight.
Of course, given an non-expedited SRCU-fast grace period blocked in
synchronize_rcu(), a later request for an expedited SRCU-fast grace
period will wait for that synchronize_rcu() to return before switching
to use of synchronize_rcu_expedited(). If this turns out to be a real
problem for a production workload, we can increase the complexity (but
likely also degrade the energy efficiency) to speed things up further.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Neeraj Upadhyay (AMD) <neeraj.upadhyay@kernel.org>
| -rw-r--r-- | kernel/rcu/srcutree.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c index 48047260697e..c5e8ebc493d5 100644 --- a/kernel/rcu/srcutree.c +++ b/kernel/rcu/srcutree.c @@ -502,6 +502,8 @@ static bool srcu_readers_active_idx_check(struct srcu_struct *ssp, int idx) */ if (!did_gp) smp_mb(); /* A */ + else if (srcu_gp_is_expedited(ssp)) + synchronize_rcu_expedited(); /* X */ else synchronize_rcu(); /* X */ |