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From:   Zqiang <qiang1.zhang@intel.com>
To:     paulmck@kernel.org, frederic@kernel.org, quic_neeraju@quicinc.com,
        joel@joelfernandes.org
Cc:     rcu@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH 1/2] rcu-tasks: Convert RCU_LOCKDEP_WARN() to WARN_ONCE()
Date:   Tue, 12 Jul 2022 16:26:05 +0800
Message-Id: <20220712082606.3662616-2-qiang1.zhang@intel.com>
In-Reply-To: <20220712082606.3662616-1-qiang1.zhang@intel.com>
References: <20220712082606.3662616-1-qiang1.zhang@intel.com>
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For kernel build with CONFIG_PROVE_RCU=y and CONFIG_DEBUG_LOCK_ALLOC=y,
when the synchronize_rcu_tasks_generic() called occurs during the
rcu_scheduler_active variable is RCU_SCHEDULER_INACTIVE, the warnings
will be trigger, however the warnings is not actually triggered because
the debug_lockdep_rcu_enabled() return false(the rcu_scheduler_active !=
RCU_SCHEDULER_INACTIVE condition is false).

This commit replace RCU_LOCKDEP_WARN() with WARN_ONCE() to trigger
warnings.

Signed-off-by: Zqiang <qiang1.zhang@intel.com>
---
 kernel/rcu/tasks.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h
index 83c7e6620d40..469bf2a3b505 100644
--- a/kernel/rcu/tasks.h
+++ b/kernel/rcu/tasks.h
@@ -560,7 +560,7 @@ static int __noreturn rcu_tasks_kthread(void *arg)
 static void synchronize_rcu_tasks_generic(struct rcu_tasks *rtp)
 {
 	/* Complain if the scheduler has not started.  */
-	RCU_LOCKDEP_WARN(rcu_scheduler_active == RCU_SCHEDULER_INACTIVE,
+	WARN_ONCE(rcu_scheduler_active == RCU_SCHEDULER_INACTIVE,
 			 "synchronize_rcu_tasks called too soon");
 
 	// If the grace-period kthread is running, use it.
-- 
2.25.1