linux-kernel - Re: [RFC PATCH] sched: find the latest idle cpu

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: <52D60F11.3070005@linux.vnet.ibm.com>
Date:	Wed, 15 Jan 2014 12:31:13 +0800
From:	Michael wang <wangyun@...ux.vnet.ibm.com>
To:	Alex Shi <alex.shi@...aro.org>, mingo@...hat.com,
	peterz@...radead.org, tglx@...utronix.de,
	daniel.lezcano@...aro.org, vincent.guittot@...aro.org,
	morten.rasmussen@....com
CC:	linux-kernel@...r.kernel.org, akpm@...ux-foundation.org,
	fengguang.wu@...el.com, linaro-kernel@...ts.linaro.org
Subject: Re: [RFC PATCH] sched: find the latest idle cpu

Hi, Alex

On 01/15/2014 12:07 PM, Alex Shi wrote:
[snip] 		}
> +#ifdef CONFIG_NO_HZ_COMMON
> +		/*
> +		 * Coarsely to get the latest idle cpu for shorter latency and
> +		 * possible power benefit.
> +		 */
> +		if (!min_load) {
> +			struct tick_sched *ts = &per_cpu(tick_cpu_sched, i);
> +
> +			s64 latest_wake = 0;

I guess we missed some code for latest_wake here?

Regards,
Michael Wang

> +			/* idle cpu doing irq */
> +			if (ts->inidle && !ts->idle_active)
> +				idlest = i;
> +			/* the cpu resched */
> +			else if (!ts->inidle)
> +				idlest = i;
> +			/* find latest idle cpu */
> +			else if (ktime_to_us(ts->idle_entrytime) > latest_wake)
> +				idlest = i;
> +		}
> +#endif
>  	}
> 
>  	return idlest;
> 

--
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/