On Tue, Apr 24, 2007 at 12:46:37AM +0400, Oleg Nesterov wrote: > On 04/23, Rafael J. Wysocki wrote: > > > > On Monday, 23 April 2007 14:35, Gautham R Shenoy wrote: > > > > + if (!freezer_should_exempt(current)) { > > > task_lock(k); > > > > + /* We are freezable, so we must make sure that the > > > > thread being > > > > + * stopped is not frozen and will not be frozen until > > > > it dies > > > > + */ > > > > + freezer_exempt(k); > > > > + if (frozen(k)) > > > > + clear_frozen_flag(k); > > > task_unlock(k); > > > > + } > > > > Yes, that's correct. We need to take task_lock() to avoid the race with > > refrigerator(). > > Even if we use thaw_task() ?
I don't think so. As you correctly pointed out, thaw_task() is race free w.r.t the refrigerator(). > > Even if I am wrong, I think we should not use task_lock() for the freezing > related code, except in freezer.[ch] > > Note also that without CONFIG_FREEZER freezer_should_exempt() == 0, so we > will do unneeded task_lock/task_unlock. > > Oleg. > Thanks and Regards gautham. -- Gautham R Shenoy Linux Technology Center IBM India. "Freedom comes with a price tag of responsibility, which is still a bargain, because Freedom is priceless!" - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/