From: Dan Williams <dan.j.williams@intel.com>
To: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: linux-nvdimm <linux-nvdimm@lists.01.org>,
"Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
Jan Kara <jack@suse.cz>, Linux MM <linux-mm@kvack.org>,
linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH] mm/pmem: Avoid inserting hugepage PTE entry with fsdax if hugepage support is disabled
Date: Fri, 5 Feb 2021 09:47:32 -0800 [thread overview]
Message-ID: <CAPcyv4ghvBwKa6pCfqLxUU9UhK9R3HY4tNrNO115QN00A8zMRw@mail.gmail.com> (raw)
In-Reply-To: <20210205023956.417587-1-aneesh.kumar@linux.ibm.com>
[ add Andrew ]
On Thu, Feb 4, 2021 at 6:40 PM Aneesh Kumar K.V
<aneesh.kumar@linux.ibm.com> wrote:
>
> Differentiate between hardware not supporting hugepages and user disabling THP
> via 'echo never > /sys/kernel/mm/transparent_hugepage/enabled'
>
> For the devdax namespace, the kernel handles the above via the
> supported_alignment attribute and failing to initialize the namespace
> if the namespace align value is not supported on the platform.
>
> For the fsdax namespace, the kernel will continue to initialize
> the namespace. This can result in the kernel creating a huge pte
> entry even though the hardware don't support the same.
>
> We do want hugepage support with pmem even if the end-user disabled THP
> via sysfs file (/sys/kernel/mm/transparent_hugepage/enabled). Hence
> differentiate between hardware/firmware lacking support vs user-controlled
> disable of THP and prevent a huge fault if the hardware lacks hugepage
> support.
Looks good to me.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
I assume this will go through Andrew.
_______________________________________________
Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org
To unsubscribe send an email to linux-nvdimm-leave@lists.01.org
next prev parent reply other threads:[~2021-02-05 17:47 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-05 2:39 [PATCH] mm/pmem: Avoid inserting hugepage PTE entry with fsdax if hugepage support is disabled Aneesh Kumar K.V
2021-02-05 8:29 ` David Hildenbrand
2021-02-05 17:47 ` Dan Williams [this message]
2021-02-10 5:18 ` Pankaj Gupta
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=CAPcyv4ghvBwKa6pCfqLxUU9UhK9R3HY4tNrNO115QN00A8zMRw@mail.gmail.com \
--to=dan.j.williams@intel.com \
--cc=akpm@linux-foundation.org \
--cc=aneesh.kumar@linux.ibm.com \
--cc=jack@suse.cz \
--cc=kirill.shutemov@linux.intel.com \
--cc=linux-mm@kvack.org \
--cc=linux-nvdimm@lists.01.org \
--cc=linuxppc-dev@lists.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).