Re: [PATCH] megaraid: add scsi_cmnd NULL check before use

[Petros Koutoupis <petros@petroskoutoupis.com>]

On Mon, 2016-05-09 at 11:35 +1000, Julian Calaby wrote:
> Hi Petros,
> 
> On Mon, May 9, 2016 at 2:34 AM, Petros Koutoupis
> <petros@petroskoutoupis.com> wrote:
> > On Sun, 2016-05-08 at 22:22 +1000, Finn Thain wrote:
> >> On Sun, 8 May 2016, Petros Koutoupis wrote:
> >>
> >> > >
> >> > > That contains a tautology.
> >> > >
> >> >
> >> > How so?
> >>
> >> if (x)
> >>       /* ... */
> >> else if (!x && (whatever))
> >>       /* ... */
> >>
> >> --
> >
> > Thank you but I know the logic of what I wrote. A tautology
> > will yield the same results no matter what the interpretation.
> > That is not a tautology. The two conditionals in my case check
> > different states and serve different purposes.
> 
> You're missing the point.
> 
> Execution will only reach the else branch if "!cmd_fusion->scmd",
> hence checking that is unnecessary. Removing that test (and all the
> unnecessary parentheses) will reduce the second test to:
> 
> else if (scsi_io_req->Function == MPI2_FUNCTION_SCSI_IO_REQUEST ||
>         scsi_io_req->Function == MEGASAS_MPI2_FUNCTION_LD_IO_REQUEST)
> 
> which is much cleaner.
> 
> Thanks,
> 

Julian,

I agree. I will clean up and resend. Thank you.