lkml.org 
[lkml]   [2009]   [Sep]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] WARN_ONCE(): use bool for boolean flag
From
Date
On Sun, 2009-09-27 at 12:56 -0300, Cesar Eduardo Barros wrote:
> Daniel Walker escreveu:
> > On Sun, 2009-09-27 at 10:53 -0300, Cesar Eduardo Barros wrote:
> >> #define
> >> WARN_ON_ONCE(condition) ({ \
> >> - static int __warned; \
> >> + static bool __warned; \
> >> int __ret_warn_once = !!(condition); \
> >
> > Could __ret_warn_once be bool also ? It looks like just another
> > conditional variable..
>
> Yes, it could (as long as either it is converted back to int in the
> return of the macro, or all users do not care about the macro's return
> type). However, the justification used for the printk_once patch (and
> this WARN_ONCE patch) does not apply directly anymore, since the code is
> different (to start with, it is not a static variable).

I did a couple kernel builds to test this on a small normal config,

vmlinux.base-line
text data bss dec hex filename
6718958 497200 1082460 8298618 7ea07a vmlinux.base-line

vmlinux.one-bool <-- Your patch
text data bss dec hex filename
6718590 497232 1082292 8298114 7e9e82 vmlinux.one-bool

vmlinux.all-bool-converted
text data bss dec hex filename
6718506 497232 1082292 8298030 7e9e2e vmlinux.all-converted

your changes drops the size 368 bytes, and if you convert the other
conditionals it drops it by another 84 bytes. Not much more, but it's
something.

So I think Rolands original reasoning still holds.. As far as people
needing an int output from WARN_ON() , I'm not sure that's happening
anyplace .. I can't imagine a sane usage for that..

Daniel



\
 
 \ /
  Last update: 2009-09-27 18:55    [W:0.507 / U:0.364 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site