linux-kernel - Re: [PATCH] sched/rt: Decrease number of calls of push_rt_task() in push_rt

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]

Message-ID: <5110C1E7.9020106@huawei.com>
Date:	Tue, 5 Feb 2013 16:25:11 +0800
From:	Honghui Zhang <zhanghonghui@...wei.com>
To:	Kirill Tkhai <tkhai@...dex.ru>
CC:	Steven Rostedt <rostedt@...dmis.org>,
	<linux-kernel@...r.kernel.org>, Ingo Molnar <mingo@...nel.org>,
	Peter Zijlstra <peterz@...radead.org>,
	linux-rt-users <linux-rt-users@...r.kernel.org>
Subject: Re: [PATCH] sched/rt: Decrease number of calls of push_rt_task()
 in push_rt_tasks()

On 2013/2/5 15:22, Kirill Tkhai wrote:
>>
>> Suppose we have a large number of cpus(say 4096), with the last one running
>> a low-priority task on it. Is it possible with this patch we will never reach
>> the last cpu in case that previous cpu has complete the pulled task?
> 
> Yes. But this patch is about several pushable tasks on the same cpu.
> 
> Kirill
> 

Maybe I haven't make myself understood, but in that case, there will be a higher-priority
task in the runqueue of the pushing cpu, and a lower-priority task running in the last cpu
which could not be preempt by push_rt_task(),  I don't think it's acceptable.

Hans


--
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/