linux-kernel - Re: Idle loadavg of ~1, maybe MD related

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:	Sun, 06 Jan 2008 14:53:12 +1100
From:	Benjamin Herrenschmidt <benh@...nel.crashing.org>
To:	Andrew Morton <akpm@...ux-foundation.org>
Cc:	"Robin H. Johnson" <robbat2@...too.org>,
	linux-kernel@...r.kernel.org, Paul Mackerras <paulus@...ba.org>
Subject: Re: Idle loadavg of ~1, maybe MD related


> Maybe, but we can usually work around it pretty comfortably.
> 
> If smu_set_fan() is only ever called by a kernel thread then we can simply
> flip it over to using wait_for_completion_interruptible().

Hrm... as of today, it's mostly called from a kernel thread but I don't
totally iron out the possibility that we add control to those things via
sysfs... But that's definitely an option for now.

However, that's only part of the problem. There's a lot of I2C accesses
(and other SMU accesses to read SMU based sensors) and I doubt we can
make all of that "magically" interruptible.

I would much prefer if we had a way to tag a kernel thread to not add to
the load average when in interruptible sleep :-)

> If smu_set_fan() is also called from user processes then things aren't so
> easy...

Ben.


--
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/