Messages in this thread | | | Subject | Re: BUGed to death | From | Sean Neakums <> | Date | Tue, 15 Apr 2003 13:49:39 +0100 |
| |
Jens Axboe <axboe@suse.de> writes:
> On Tue, Apr 15 2003, Duncan Sands wrote: >> On Monday 14 April 2003 22:19, Martin J. Bligh wrote: >> > Seems all these bug checks are fairly expensive. I can get 1% >> > back on system time for kernel compiles by changing BUG to >> > "do {} while (0)" to make them all compile away. Profiles aren't >> > very revealing though ... seems to be within experimental error ;-( >> >> What happens if you just turn BUG_ON into "do {} while (0)"? > > If you do that, you must audit every single BUG_ON to make sure the > expression doesn't have any side effects. > > BUG_ON(do_the_good_stuff());
#define BUG_ON(x) x; do the trick. With any luck the compiler will throw away most of the simple comparisons and whatnot.
-- Sean Neakums - <sneakums@zork.net> - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |