Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   "Joel Fernandes (Google)" <joel@joelfernandes.org>
To:     rcu@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org, rushikesh.s.kadam@intel.com,
        urezki@gmail.com, neeraj.iitr10@gmail.com, frederic@kernel.org,
        paulmck@kernel.org, rostedt@goodmis.org, youssefesmat@google.com,
        surenb@google.com, Joel Fernandes <joel@joelfernandes.org>
Subject: [PATCH v8 10/13] scsi/scsi_error: Use call_rcu_flush() instead of call_rcu()
Date:   Tue, 11 Oct 2022 18:01:39 +0000
Message-Id: <20221011180142.2742289-11-joel@joelfernandes.org>
In-Reply-To: <20221011180142.2742289-1-joel@joelfernandes.org>
References: <20221011180142.2742289-1-joel@joelfernandes.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Uladzislau Rezki <urezki@gmail.com>

Slow boot time is seen on KVM running typical Linux distributions due to
SCSI layer calling call_rcu(). Recent changes to save power may be
causing this slowness. Using call_rcu_flush() fixes the issue and brings
the boot time back to what it originally was. Convert it.

Tested-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Uladzislau Rezki <urezki@gmail.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
---
 drivers/scsi/scsi_error.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index 448748e3fba5..a56cfd612e3a 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -312,7 +312,7 @@ void scsi_eh_scmd_add(struct scsi_cmnd *scmd)
 	 * Ensure that all tasks observe the host state change before the
 	 * host_failed change.
 	 */
-	call_rcu(&scmd->rcu, scsi_eh_inc_host_failed);
+	call_rcu_flush(&scmd->rcu, scsi_eh_inc_host_failed);
 }
 
 /**
-- 
2.38.0.rc1.362.ged0d419d3c-goog