linuxppc-dev.lists.ozlabs.org archive mirror
 help / color / mirror / Atom feed
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: fweisbec@gmail.com, linux-kernel@vger.kernel.org,
	paulus@samba.org, paulmck@linux.vnet.ibm.com,
	linuxppc-dev@lists.ozlabs.org
Subject: Re: [RFC PATCH v3 2/5] powerpc: Exception hooks for context tracking subsystem
Date: Mon, 13 May 2013 19:06:31 +1000	[thread overview]
Message-ID: <1368435991.19924.35.camel@pasglop> (raw)
In-Reply-To: <1368434680.2618.33.camel@ThinkPad-T5421>

On Mon, 2013-05-13 at 16:44 +0800, Li Zhong wrote:
> Yes, the above and hash_page() are two C functions for a same exception.
> And the exception hooks enable RCU usage in those C codes. But for asm
> codes, I think we could assume that there would be no RCU usage there,
> so we don't need wrap them in the hooks.

hash_page() won't start a new RCU, at least not in its current incarnation,
the only thing I can see it ever doing would be to take some RCU read locks one
day (it doesn't today).

low_hash_fault() is a different beast. It will typically kill things, thus
involving sending signals etc... RCU might well be involved.

Cheers,
Ben.

  reply	other threads:[~2013-05-13  9:06 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-05-13  5:21 [RFC PATCH v3 0/5] powerpc: Support context tracking for Power pSeries Li Zhong
2013-05-13  5:21 ` [RFC PATCH v3 1/5] powerpc: Syscall hooks for context tracking subsystem Li Zhong
2013-05-13  5:21 ` [RFC PATCH v3 2/5] powerpc: Exception " Li Zhong
2013-05-13  5:57   ` Benjamin Herrenschmidt
2013-05-13  8:44     ` Li Zhong
2013-05-13  9:06       ` Benjamin Herrenschmidt [this message]
2013-05-13  9:46         ` Li Zhong
2013-05-13 10:01           ` Benjamin Herrenschmidt
2013-05-13  5:21 ` [RFC PATCH v3 3/5] powerpc: Exit user context on notify resume Li Zhong
2013-05-13  5:21 ` [RFC PATCH v3 4/5] powerpc: Use the new schedule_user API on userspace preemption Li Zhong
2013-05-13  5:21 ` [RFC PATCH v3 5/5] powerpc: select HAVE_CONTEXT_TRACKING for pSeries Li Zhong
2013-05-13  5:51 ` [RFC PATCH v3 0/5] powerpc: Support context tracking for Power pSeries Benjamin Herrenschmidt
2013-05-13  8:03   ` Li Zhong
2013-05-13  8:59     ` Benjamin Herrenschmidt
2013-05-13  9:22       ` Li Zhong
2013-05-29 21:32       ` Frederic Weisbecker
2013-05-29 21:29     ` Frederic Weisbecker

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=1368435991.19924.35.camel@pasglop \
    --to=benh@kernel.crashing.org \
    --cc=fweisbec@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=paulmck@linux.vnet.ibm.com \
    --cc=paulus@samba.org \
    --cc=zhong@linux.vnet.ibm.com \
    /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).