From: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
To: Christophe LEROY <christophe.leroy@c-s.fr>
Cc: "linuxppc-dev\@lists.ozlabs.org" <linuxppc-dev@lists.ozlabs.org>
Subject: Re: Question on hugepages_supported()
Date: Wed, 02 Aug 2017 12:58:38 +0530 [thread overview]
Message-ID: <87a83i1l95.fsf@linux.vnet.ibm.com> (raw)
In-Reply-To: <bbc6ae12-1705-32e1-109b-baefead9444b@c-s.fr>
Christophe LEROY <christophe.leroy@c-s.fr> writes:
> In include/linux/hugetlb.h, we find the following statement
>
> #ifndef hugepages_supported
> /*
> * Some platform decide whether they support huge pages at boot
> * time. Some of them, such as powerpc, set HPAGE_SHIFT to 0
> * when there is no such support
> */
> #define hugepages_supported() (HPAGE_SHIFT != 0)
> #endif
>
> But in arch/powerpc/include/asm/page.h we find:
>
> #ifdef CONFIG_HUGETLB_PAGE
> extern unsigned int HPAGE_SHIFT;
> #else
> #define HPAGE_SHIFT PAGE_SHIFT
> #endif
>
>
> Is that correct ? SHouldn't HPAGE_SHIFT be defined to 0 when
> CONFIG_HUGETLB_PAGE is not defined ?
>
But then hugepages_supported() is only defined if HUGETLB_PAGE is
enabled. So yes we can possibly say HPAGE_SHIFT = 0 if HUGETLB is
disabled, I am not sure it has any impact with the current code ?
-aneesh
prev parent reply other threads:[~2017-08-02 7:29 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-08-02 7:03 Question on hugepages_supported() Christophe LEROY
2017-08-02 7:28 ` Aneesh Kumar K.V [this message]
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=87a83i1l95.fsf@linux.vnet.ibm.com \
--to=aneesh.kumar@linux.vnet.ibm.com \
--cc=christophe.leroy@c-s.fr \
--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).