linux-kernel - Re: [PATCH v4] sched/deadline: remove useless param from setup_new_dl

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Fri, 5 Aug 2016 11:13:14 +0100
From:	Juri Lelli <juri.lelli@....com>
To:	xlpang@...hat.com
Cc:	peterz@...radead.org, rostedt@...dmis.org,
	linux-kernel@...r.kernel.org, mingo@...hat.com, luca.abeni@...tn.it
Subject: Re: [PATCH v4] sched/deadline: remove useless param from
 setup_new_dl_entity

On 22/07/16 10:58, Xunlei Pang wrote:
> On 2016/07/21 at 22:46, Juri Lelli wrote:
[...]
> > @@ -1734,9 +1724,11 @@ static void switched_to_dl(struct rq *rq, struct task_struct *p)
> >  	if (task_on_rq_queued(p)) {
> >  		/*
> >  		 * If p is not queued we will update its parameters at next
> > -		 * wakeup.
> > +		 * wakeup. If p is dl_boosted we already updated its params in
> > +		 * rt_mutex_setprio()->enqueue_task(..., ENQUEUE_REPLENISH).
> >  		 */
> > -		if (dl_time_before(p->dl.deadline, rq_clock(rq)))
> > +		if (dl_time_before(p->dl.deadline, rq_clock(rq)) &&
> > +				!p->dl.dl_boosted)
> 
> Hi Juri,
> 
> It looks good to me, only one question:
> For on_rq boosted to deadline, p->dl.deadline has been updated after rq_lock(rq) by
> rt_mutex_setprio()->enqueue_task(..., ENQUEUE_REPLENISH) and no rq clock update
> afterwards, so dl_time_before() will be false, seems p->dl.dl_boosted check is needless.
> 

Right. I removed it and posted v5. Please have a look.

Best,

- Juri