On Thu, 6 Jan 2000, Petko Manolov wrote:
> GCC optimize(reorder) "jiffies++" and "(*(unsigned long *)&jiffies)++"
> is
> used to be sure jiffies is incremented exactly where/when you want.
Ok, then it applies to lost_ticks and lost_ticks_system as well. And
therefore a cleaner way of doing it (as Richard Johnson suggested) would
be in asm:
--- timer.c.0 Thu Jan 6 15:13:21 2000
+++ timer.c Thu Jan 6 15:15:31 2000
@@ -629,12 +629,11 @@
void do_timer(struct pt_regs * regs)
{
- /* (*(unsigned long *)&jiffies)++; */
- jiffies++;
- lost_ticks++;
+ __asm__ __volatile__("incl jiffies");
+ __asm__ __volatile__("incl lost_ticks");
mark_bh(TIMER_BH);
if (!user_mode(regs))
- lost_ticks_system++;
+ __asm__ __volatile__("incl lost_ticks_system");
if (tq_timer)
mark_bh(TQUEUE_BH);
}
Thsi is better than the *& hack because it is gcc-version-independent.
Regards,
------
Tigran A. Aivazian | http://www.sco.com
Escalations Research Group | tel: +44-(0)1923-813796
Santa Cruz Operation Ltd | http://www.ocston.org/~tigran
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