From: Mel Gorman <mgorman@techsingularity.net>
To: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: akpm@linux-foundation.org, Rik van Riel <riel@surriel.com>,
linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/autonuma: don't use set_pte_at when updating protnone ptes
Date: Mon, 6 Feb 2017 22:26:42 +0000 [thread overview]
Message-ID: <20170206222642.u2e5ip4h2udaehr4@techsingularity.net> (raw)
In-Reply-To: <1486400776-28114-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com>
On Mon, Feb 06, 2017 at 10:36:16PM +0530, Aneesh Kumar K.V wrote:
> Architectures like ppc64, use privilege access bit to mark pte non accessible.
> This implies that kernel can do a copy_to_user to an address marked for numa fault.
> This also implies that there can be a parallel hardware update for the pte.
> set_pte_at cannot be used in such scenarios. Hence switch the pte
> update to use ptep_get_and_clear and set_pte_at combination.
>
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Yeah, ok. The main thing is that it still avoids doing an unnecessary TLB
flush so
Acked-by: Mel Gorman <mgorman@techsingularity.net>
--
Mel Gorman
SUSE Labs
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
WARNING: multiple messages have this Message-ID (diff)
From: Mel Gorman <mgorman@techsingularity.net>
To: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: akpm@linux-foundation.org, Rik van Riel <riel@surriel.com>,
linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/autonuma: don't use set_pte_at when updating protnone ptes
Date: Mon, 6 Feb 2017 22:26:42 +0000 [thread overview]
Message-ID: <20170206222642.u2e5ip4h2udaehr4@techsingularity.net> (raw)
In-Reply-To: <1486400776-28114-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com>
On Mon, Feb 06, 2017 at 10:36:16PM +0530, Aneesh Kumar K.V wrote:
> Architectures like ppc64, use privilege access bit to mark pte non accessible.
> This implies that kernel can do a copy_to_user to an address marked for numa fault.
> This also implies that there can be a parallel hardware update for the pte.
> set_pte_at cannot be used in such scenarios. Hence switch the pte
> update to use ptep_get_and_clear and set_pte_at combination.
>
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Yeah, ok. The main thing is that it still avoids doing an unnecessary TLB
flush so
Acked-by: Mel Gorman <mgorman@techsingularity.net>
--
Mel Gorman
SUSE Labs
next prev parent reply other threads:[~2017-02-06 22:26 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-02-06 17:06 [PATCH] mm/autonuma: don't use set_pte_at when updating protnone ptes Aneesh Kumar K.V
2017-02-06 17:06 ` Aneesh Kumar K.V
2017-02-06 18:46 ` Rik van Riel
2017-02-06 22:26 ` Mel Gorman [this message]
2017-02-06 22:26 ` Mel Gorman
2017-02-07 8:09 ` John Hubbard
2017-02-14 14:11 ` Aneesh Kumar K.V
2017-02-14 14:11 ` Aneesh Kumar K.V
2017-02-15 0:05 ` Andrew Morton
2017-02-15 0:05 ` Andrew Morton
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=20170206222642.u2e5ip4h2udaehr4@techsingularity.net \
--to=mgorman@techsingularity.net \
--cc=akpm@linux-foundation.org \
--cc=aneesh.kumar@linux.vnet.ibm.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=riel@surriel.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.