Re: Scheduler ugliness-fix

Linus Torvalds (torvalds@transmeta.com)
Wed, 8 Jul 1998 10:32:01 -0700 (PDT)


On Wed, 8 Jul 1998, Pavel Machek wrote:
>
> This is bugfix. (Or more uggliness-fix. No need to try to fool gcc
> when jiffies are volatile, anyway, also (~0UL == 0xffffffff) tests
> fail when cross compiling and we already have clean way to do this.

The _reason_ for the ugliness is apparent when you look at the assembly
code before and after your patch.

gcc simply creates horrible code for updates to volatile variables, for no
good reason. As the "volatility" of jiffies is an artifact to just make
gcc not optimize certain timing loops, the strange cast is perfectly
acceptable.

Linus

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