Messages in this thread Patch in this message | | | Date | Wed, 30 Jun 2021 13:47:28 -0000 | From | "tip-bot2 for Frederic Weisbecker" <> | Subject | [tip: core/rcu] rcu/nocb: Only cancel nocb timer if not polling |
| |
The following commit has been merged into the core/rcu branch of tip:
Commit-ID: f9fc166b790bd214083035d865653133b8a963d1 Gitweb: https://git.kernel.org/tip/f9fc166b790bd214083035d865653133b8a963d1 Author: Frederic Weisbecker <frederic@kernel.org> AuthorDate: Tue, 23 Feb 2021 01:10:09 +01:00 Committer: Paul E. McKenney <paulmck@kernel.org> CommitterDate: Wed, 12 May 2021 12:10:23 -07:00
rcu/nocb: Only cancel nocb timer if not polling
This commit refrains deleting the ->nocb_timer if rcu_nocb is polling because it should not ever have been queued in the polling case.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: Joel Fernandes <joel@joelfernandes.org> Cc: Neeraj Upadhyay <neeraju@codeaurora.org> Cc: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> --- kernel/rcu/tree_plugin.h | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 4253a0e..db28e31 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -2176,18 +2176,18 @@ static void nocb_gp_wait(struct rcu_data *my_rdp) my_rdp->nocb_gp_gp = needwait_gp; my_rdp->nocb_gp_seq = needwait_gp ? wait_gp_seq : 0; if (bypass) { - raw_spin_lock_irqsave(&my_rdp->nocb_gp_lock, flags); - // Avoid race with first bypass CB. - if (my_rdp->nocb_defer_wakeup > RCU_NOCB_WAKE_NOT) { - WRITE_ONCE(my_rdp->nocb_defer_wakeup, RCU_NOCB_WAKE_NOT); - del_timer(&my_rdp->nocb_timer); - } if (!rcu_nocb_poll) { + raw_spin_lock_irqsave(&my_rdp->nocb_gp_lock, flags); + // Avoid race with first bypass CB. + if (my_rdp->nocb_defer_wakeup > RCU_NOCB_WAKE_NOT) { + WRITE_ONCE(my_rdp->nocb_defer_wakeup, RCU_NOCB_WAKE_NOT); + del_timer(&my_rdp->nocb_timer); + } // At least one child with non-empty ->nocb_bypass, so set // timer in order to avoid stranding its callbacks. mod_timer(&my_rdp->nocb_bypass_timer, j + 2); + raw_spin_unlock_irqrestore(&my_rdp->nocb_gp_lock, flags); } - raw_spin_unlock_irqrestore(&my_rdp->nocb_gp_lock, flags); } if (rcu_nocb_poll) { /* Polling, so trace if first poll in the series. */
| |