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sh_eth: kill redundant check in the probe() method

PATCH In review Sergei Shtylyov 2 participants 2 messages Dec 31, 2017 – Jan 2, 2018

Subsystems (3)
Networking Network drivers Renesas SuperH Ethernet driver
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Sergei Shtylyov

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#0 lore raw

PATCH 2/2 sh_eth: kill redundant check in the probe() method

Browsing thru the driver diassembly, I noticed that gcc was able to figure out that the 'ndev' pointer is always non-NULL when calling free_netdev() on the probe() method's error path and thus skip that redundant NULL check... gcc is smart, be like gcc! :-)

Signed-off-by Sergei Shtylyov <[email protected]>
---
 drivers/net/ethernet/renesas/sh_eth.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)
drivers/net/ethernet/renesas/sh_eth.c +1 -2
Index: net-next/drivers/net/ethernet/renesas/sh_eth.c
===================================================================
@@ -3282,8 +3282,7 @@ out_napi_del:
 
 out_release:
 	/* net_dev free */
-	if (ndev)
-		free_netdev(ndev);
+	free_netdev(ndev);
 
 	pm_runtime_put(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
Reviewed-by on v1 2/2
#1 lore raw

H Sergei,

Quoted 4 lines · Sergei Shtylyov

Browsing thru the driver diassembly, I noticed that gcc was able to figure out that the 'ndev' pointer is always non-NULL when calling free_netdev() on the probe() method's error path and thus skip that redundant NULL check... gcc is smart, be like gcc! :-)

Thanks for your patch!

Quoted 1 line
Signed-off-by Sergei Shtylyov <[email protected]>
Reviewed-by Geert Uytterhoeven <[email protected]>

drivers/net/ethernet/renesas/sh_eth.c out_napi_del: · line 3288

Quoted 12 lines
drivers/net/ethernet/renesas/sh_eth.c +1 -2
@@ -3282,8 +3282,7 @@ out_napi_del:
 
 out_release:
        /* net_dev free */
-       if (ndev)
-               free_netdev(ndev);
+       free_netdev(ndev);
 
        pm_runtime_put(&pdev->dev);
        pm_runtime_disable(&pdev->dev);

BTW, there isn't a functional dependency, but you may want to move the freeing of the netdev below disabling of Runtime PM for symmetry (use reverse order in cleanup).

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]

In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds