linux-kernel - Re: [RFC PATCHC 2/3] idle: store the idle state the cpu is

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]

Date:	Tue, 15 Apr 2014 14:43:30 +0200
From:	Peter Zijlstra <peterz@...radead.org>
To:	Daniel Lezcano <daniel.lezcano@...aro.org>
Cc:	linux-kernel@...r.kernel.org, mingo@...e.hu, rjw@...ysocki.net,
	nicolas.pitre@...aro.org, linux-pm@...r.kernel.org,
	alex.shi@...aro.org, vincent.guittot@...aro.org,
	morten.rasmussen@....com
Subject: Re: [RFC PATCHC 2/3] idle: store the idle state the cpu is

On Fri, Mar 28, 2014 at 01:29:55PM +0100, Daniel Lezcano wrote:
> @@ -143,6 +145,10 @@ static int cpuidle_idle_call(void)
>  			if (!ret) {
>  				trace_cpu_idle_rcuidle(next_state, dev->cpu);
>  
> +				*power = &drv->states[next_state].power;
> +
> +				wmb();
> +

I very much suspect you meant: smp_wmb(), as I don't see the hardware
reading that pointer, therefore UP wouldn't care. Also, any and all
barriers should come with a comment that describes the data ordering and
points to the matchin barriers.
--
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/