linux-kernel - Re: [PATCH 1/2] sched: recover SD_WAKE_AFFINE in select_task_rq

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

Message-ID: <501110FD.9070308@intel.com>
Date:	Thu, 26 Jul 2012 17:42:21 +0800
From:	Alex Shi <alex.shi@...el.com>
To:	Mike Galbraith <efault@....de>
CC:	mingo@...hat.com, peterz@...radead.org,
	linux-kernel@...r.kernel.org, suresh.b.siddha@...el.com
Subject: Re: [PATCH 1/2] sched: recover SD_WAKE_AFFINE in select_task_rq_fair
 and code clean up

On 07/26/2012 05:37 PM, Mike Galbraith wrote:

> On Thu, 2012-07-26 at 13:27 +0800, Alex Shi wrote:
> 
>> 	if (affine_sd) {
>> -		if (cpu == prev_cpu || wake_affine(affine_sd, p, sync))
>> +		if (wake_affine(affine_sd, p, sync))
>>  			prev_cpu = cpu;
>>  
>>  		new_cpu = select_idle_sibling(p, prev_cpu);
> 
> Hm, if cpu == prev_cpu, asking wake_affine() if it's ok to put wakee
> back where it came from is wasted cycles.. that's where the task is
> headed regardless of reply.


Sure. You'r right.

> 
> -Mike
> 


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/