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  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:	Mon, 10 Nov 2014 13:29:54 +0100
From:	Peter Zijlstra <>
To:	Daniel Lezcano <>
Subject: Re: [PATCH V3 1/6] sched: idle: Add a weak arch_cpu_idle_poll

On Fri, Nov 07, 2014 at 03:31:22PM +0100, Daniel Lezcano wrote:
> The poll function is called when a timer expired or if we force to poll when
> the cpu_idle_force_poll option is set.
> The poll function does:
>        local_irq_enable();
>        while (!tif_need_resched())
>                cpu_relax();
> This default poll function suits for the x86 arch because its rep; nop;
> hardware power optimization. But on other archs, this optimization does not
> exists and we are not saving power. The arch specific bits may want to
> optimize this loop by adding their own optimization.

This doesn't make sense to me; should an arch not either implement an
actual idle driver or implement cpu_relax() properly, why allow for a
third weird option?
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

Powered by blists - more mailing lists