Re: [PATCH] net: xfrm_user: use BUG_ON instead of if condition followed by BUG

[David Miller]

From: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Date: Tue, 24 Oct 2017 11:25:08 +0800

> On Mon, Oct 23, 2017 at 01:18:57PM -0500, Gustavo A. R. Silva wrote:
>> Use BUG_ON instead of if condition followed by BUG.
>> 
>> This issue was detected with the help of Coccinelle.
>> 
>> Signed-off-by: Gustavo A. R. Silva <garsilva@xxxxxxxxxxxxxx>
> 
> I think this patch is terrible.  Why on earth is Coccinelle even
> warning about this?

BUG_ON(x) generates significantly better code than
"if (cond) BUG();" because it's not possible to emit
the most optimal code sequences like on powerpc that has
conditional traps.

That's why.

I'm applying these transformations all over the networking as I
receive them and I advise that you do so for crypto as well.

Thank.