linux-kernel - [PATCH 2/4] rcu: No need to reset the poll request flag before completion

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20220316144255.336021-3-frederic@kernel.org>
Date:   Wed, 16 Mar 2022 15:42:53 +0100
From:   Frederic Weisbecker <frederic@...nel.org>
To:     "Paul E . McKenney" <paulmck@...nel.org>
Cc:     LKML <linux-kernel@...r.kernel.org>,
        Frederic Weisbecker <frederic@...nel.org>,
        Uladzislau Rezki <uladzislau.rezki@...y.com>,
        Boqun Feng <boqun.feng@...il.com>,
        Neeraj Upadhyay <quic_neeraju@...cinc.com>,
        Joel Fernandes <joel@...lfernandes.org>
Subject: [PATCH 2/4] rcu: No need to reset the poll request flag before completion

The flag allowing to requeue the polling work is reset before the
polling even starts. However there is no point in having two competing
polling on the same grace period. Just reset the flag once we have
completed the grace period only.

Signed-off-by: Frederic Weisbecker <frederic@...nel.org>
Cc: Neeraj Upadhyay <quic_neeraju@...cinc.com>
Cc: Boqun Feng <boqun.feng@...il.com>
Cc: Uladzislau Rezki <uladzislau.rezki@...y.com>
Cc: Joel Fernandes <joel@...lfernandes.org>
---
 kernel/rcu/tree_exp.h | 1 -
 1 file changed, 1 deletion(-)

diff --git a/kernel/rcu/tree_exp.h b/kernel/rcu/tree_exp.h
index b6fd857f34ba..763ec35546ed 100644
--- a/kernel/rcu/tree_exp.h
+++ b/kernel/rcu/tree_exp.h
@@ -911,7 +911,6 @@ static void sync_rcu_do_polled_gp(struct work_struct *wp)
 
 	raw_spin_lock_irqsave(&rnp->exp_poll_lock, flags);
 	s = rnp->exp_seq_poll_rq;
-	rnp->exp_seq_poll_rq |= 0x1;
 	raw_spin_unlock_irqrestore(&rnp->exp_poll_lock, flags);
 	if (s & 0x1)
 		return;
-- 
2.25.1