[PATCH] ARM: OMAP2: Delete unnecessary checks before three function calls

Paul Walmsley paul at pwsan.com
Thu Jul 16 07:06:44 PDT 2015


On Wed, 15 Jul 2015, Tony Lindgren wrote:

> * Paul Walmsley <paul at pwsan.com> [150715 22:58]:
> > Hello Markus
> > 
> > On Tue, 30 Jun 2015, SF Markus Elfring wrote:
> > 
> > > From: Markus Elfring <elfring at users.sourceforge.net>
> > > Date: Tue, 30 Jun 2015 14:00:16 +0200
> > > 
> > > The functions clk_disable(), of_node_put() and omap_device_delete() test
> > > whether their argument is NULL and then return immediately.
> > > Thus the test around the call is not needed.
> > > 
> > > This issue was detected by using the Coccinelle software.
> > > 
> > > Signed-off-by: Markus Elfring <elfring at users.sourceforge.net>
> > 
> > Thanks for the patch.  I have to say, I am a bit leery about applying the 
> > omap_device.c and omap_hwmod.c changes, since the called functions -- 
> > omap_device_delete() and clk_disable() -- don't explicitly document that 
> > NULLs are allowed to be passed in.  So there's no explicit contract that 
> > callers can rely upon, to (at least in theory) prevent those internal NULL 
> > pointer checks from being removed.
> > 
> > So I would suggest that those two functions' kerneldoc be patched first to 
> > explicitly state that passing in a NULL pointer is allowed.  Then I would 
> > feel a bit more comfortable applying the omap_device.c and omap_hwmod.c 
> > changes.
> > 
> > The kerneldoc for of_node_put() does explicitly allow NULLs to be passed 
> > in.  So I'll apply that change now for v4.3, touching up the commit 
> > message accordingly.
> 
> I have them applied from a later thread already, but will drop both in
> my branch as I have not pushed them out yet.

Oops sorry about stepping on your toes - I obviously missed that followup.

- Paul



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