Re: [RFC] asm-generic: default BUG_ON(x) to "if(x) BUG()"

Russell King - ARM Linux
2015-11-23T17:22:13Z

On Mon, Nov 23, 2015 at 05:52:38PM +0100, Arnd Bergmann wrote:
> On Monday 23 November 2015 16:37:50 Russell King - ARM Linux wrote:
> > Does that not depend on the architectures BUG() implementation? If an
> > architecture implements it as a signalling illegal instruction and a
> > lookup table, changing it to be a panic() would probably be more code.
>
> Correct, overall, we are down to a 1.40% size reduction compared to
> 1.70% without my patch and 1.49% with my version:
>
> section CONFIG_BUG=y CONFIG_BUG=n CONFIG_BUG=n+patch panic("BUG!")
>
> .text 8320248 | 8180944 | 8207688 | 8221848
> .rodata 3633720 | 3567144 | 3570648 | 3567344
> __bug_table 32508 | --- | --- | ---
> __modver 692 | 1584 | 2176 | 1384
> .init.text 558132 | 548300 | 550088 | 550592
> .exit.text 12380 | 12256 | 12380 | 12448
> .data 1016672 | 1016064 | 1016128 | 1016064
> Total 14622556 | 14374510 | 14407326 | 14417898

Are you including dropping the bug table in these stats? See BUG_TABLE
in include/asm-generic/vmlinux.lds.h.

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