Thread (4 messages) 4 messages, 2 authors, 2018-03-30

Re: [PATCH v2 2/2] net: mvneta: improve suspend/resume

From: Russell King - ARM Linux <linux@armlinux.org.uk>
Date: 2018-03-30 10:43:24
Also in: linux-arm-kernel, lkml

On Fri, Mar 30, 2018 at 06:36:15PM +0800, Jisheng Zhang wrote:
Current suspend/resume implementation reuses the mvneta_open() and
mvneta_close(), but it could be optimized to take only necessary
actions during suspend/resume.

One obvious problem of current implementation is: after hundreds of
system suspend/resume cycles, the resume of mvneta could fail due to
fragmented dma coherent memory. After this patch, the non-necessary
memory alloc/free is optimized out.
I don't think you've properly tested this.  Please ensure that you test
patches with the appropriate debug options enabled.
quoted hunk ↗ jump to hunk
@@ -4586,16 +4586,43 @@ static int mvneta_remove(struct platform_device *pdev)
 #ifdef CONFIG_PM_SLEEP
 static int mvneta_suspend(struct device *device)
 {
+	int queue;
 	struct net_device *dev = dev_get_drvdata(device);
 	struct mvneta_port *pp = netdev_priv(dev);
 
-	rtnl_lock();
-	if (netif_running(dev))
-		mvneta_stop(dev);
-	rtnl_unlock();
...
+	mvneta_stop_dev(pp);
You're removing the rtnl_lock() that I introduced in 3b8bc67413de
("net: mvneta: ensure PM paths take the rtnl lock") which is necessary
to provide phylink with consistent locking.  mvneta_stop_dev() calls
phylink_stop() which will check that the rtnl lock is held, and will
print a warning if it isn't.

Your patch will cause a regression here.
quoted hunk ↗ jump to hunk
+
+	for (queue = 0; queue < rxq_number; queue++) {
+		struct mvneta_rx_queue *rxq = &pp->rxqs[queue];
+
+		mvneta_rxq_drop_pkts(pp, rxq);
+	}
+
+	for (queue = 0; queue < txq_number; queue++) {
+		struct mvneta_tx_queue *txq = &pp->txqs[queue];
+
+		mvneta_txq_hw_deinit(pp, txq);
+	}
+
+clean_exit:
 	netif_device_detach(dev);
 	clk_disable_unprepare(pp->clk_bus);
 	clk_disable_unprepare(pp->clk);
+
 	return 0;
 }
 
@@ -4604,7 +4631,7 @@ static int mvneta_resume(struct device *device)
 	struct platform_device *pdev = to_platform_device(device);
 	struct net_device *dev = dev_get_drvdata(device);
 	struct mvneta_port *pp = netdev_priv(dev);
-	int err;
+	int err, queue;
 
 	clk_prepare_enable(pp->clk);
 	if (!IS_ERR(pp->clk_bus))
@@ -4626,12 +4653,36 @@ static int mvneta_resume(struct device *device)
 	}
 
 	netif_device_attach(dev);
-	rtnl_lock();
-	if (netif_running(dev)) {
-		mvneta_open(dev);
-		mvneta_set_rx_mode(dev);
...
 	}
-	rtnl_unlock();
...
+	mvneta_start_dev(pp);
Same applies here.

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 8.8Mbps down 630kbps up
According to speedtest.net: 8.21Mbps down 510kbps up
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help