Re: [EXT] Re: [PATCH v2] lib/cryptodev: fix assertion to remove GCC compilation warning

[Stephen Hemminger <stephen@networkplumber.org>]

On Tue, 23 May 2023 08:12:28 +0000
Akhil Goyal <gakhil@marvell.com> wrote:

> > 
> > This could happen if the passed in length to this routine was larger than
> > the amount of data in the mbuf. Should the function check and return an error?
> > 
> > Panic should only be reserved for seriously corrupted input (like invalid mbuf).
> > 
> > Also, this is a big enough function that it really should not be inlined.  
> 
> This is a datapath API. RTE_ASSERT is normally not enabled in release build.
> So, this assert is not doing any check for normal scenario.
> We normally avoid these type of error checks in the datapath.
> And while building in debug mode, we need these asserts to give a backtrace also
> To debug the rootcause of the issue.
> 
> I would suggest fixing the assert itself instead of adding a check.
> Current patch will affect performance.
> 
> Agreed, that the function is big for being an inline function,
> but that is what all the datapath APIs are and
> we keep them inline to improve the performance.

Inline is not a magic go fast switch. Turns out that the compilers and cpu's
already do good job with functions.  Using LTO helps too.