linux-kernel - [PATCH 06/11] rcu/nocb: Remove halfway (de-)offloading handling from bypass

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Message-ID: <20240530134552.5467-7-frederic@kernel.org>
Date: Thu, 30 May 2024 15:45:47 +0200
From: Frederic Weisbecker <frederic@...nel.org>
To: LKML <linux-kernel@...r.kernel.org>
Cc: Frederic Weisbecker <frederic@...nel.org>,
	Boqun Feng <boqun.feng@...il.com>,
	Joel Fernandes <joel@...lfernandes.org>,
	Neeraj Upadhyay <neeraj.upadhyay@....com>,
	"Paul E . McKenney" <paulmck@...nel.org>,
	Uladzislau Rezki <urezki@...il.com>,
	Zqiang <qiang.zhang1211@...il.com>,
	rcu <rcu@...r.kernel.org>
Subject: [PATCH 06/11] rcu/nocb: Remove halfway (de-)offloading handling from bypass

Bypass enqueue can't happen anymore in the middle of (de-)offloading
since this sort of transition now only applies to offline CPUs.

The related safety check can therefore be removed.

Signed-off-by: Frederic Weisbecker <frederic@...nel.org>
---
 kernel/rcu/tree_nocb.h | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/kernel/rcu/tree_nocb.h b/kernel/rcu/tree_nocb.h
index 8e766396df3a..af44e75eb0cd 100644
--- a/kernel/rcu/tree_nocb.h
+++ b/kernel/rcu/tree_nocb.h
@@ -409,14 +409,6 @@ static bool rcu_nocb_try_bypass(struct rcu_data *rdp, struct rcu_head *rhp,
 		return false;
 	}
 
-	// In the process of (de-)offloading: no bypassing, but
-	// locking.
-	if (!rcu_segcblist_completely_offloaded(&rdp->cblist)) {
-		rcu_nocb_lock(rdp);
-		*was_alldone = !rcu_segcblist_pend_cbs(&rdp->cblist);
-		return false; /* Not offloaded, no bypassing. */
-	}
-
 	// Don't use ->nocb_bypass during early boot.
 	if (rcu_scheduler_active != RCU_SCHEDULER_RUNNING) {
 		rcu_nocb_lock(rdp);
-- 
2.45.1