From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: linuxppc-dev@ozlabs.org
Subject: Re: Chenging 2 bits in MSR in ppc6xx_idle() with 1 command?
Date: Thu, 28 Dec 2006 08:15:16 +1100 [thread overview]
Message-ID: <1167254116.23340.14.camel@localhost.localdomain> (raw)
In-Reply-To: <Pine.LNX.4.60.0612272135470.13342@poirot.grange>
> Hm, wouldn't it just work? In ppc6xx_idle() the _TLF_NAPPING bit is set.
> If as a result of mtmsr only the EE bit is set and we get an interrupt, we
> end up in transfer_to_handler(), check the flag, it is set, so we branch
> to power_save_6xx_restore(). There we clear NAP/DOZE and just jump to
> transfer_to_handler_cont(). Why did you say we'd miss the check for
> need_resched (on IRC)? How is this case difference from if we really did
> go to NAP / DOZE?
>
> Are there other places in the kernel where we rely on setting MSR:POW and
> some other bit atomically?
Indeed, the napping "recovery" code might save us here... funny, as it
wasn't implemented to handle that case at all...
Ben.
next prev parent reply other threads:[~2006-12-27 21:15 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-12-25 20:07 Chenging 2 bits in MSR in ppc6xx_idle() with 1 command? Guennadi Liakhovetski
2006-12-26 23:48 ` Benjamin Herrenschmidt
2006-12-26 23:56 ` Guennadi Liakhovetski
2006-12-27 20:44 ` Guennadi Liakhovetski
2006-12-27 21:15 ` Benjamin Herrenschmidt [this message]
2006-12-28 2:30 ` Segher Boessenkool
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1167254116.23340.14.camel@localhost.localdomain \
--to=benh@kernel.crashing.org \
--cc=g.liakhovetski@gmx.de \
--cc=linuxppc-dev@ozlabs.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).