From: Pingfan Liu <kernelfans@gmail.com>
To: Ira Weiny <ira.weiny@intel.com>
Cc: Linux-mm@kvack.org, Andrew Morton <akpm@linux-foundation.org>,
Mike Rapoport <rppt@linux.ibm.com>,
"Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
Thomas Gleixner <tglx@linutronix.de>,
John Hubbard <jhubbard@nvidia.com>,
"Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>,
Christoph Hellwig <hch@lst.de>,
Keith Busch <keith.busch@intel.com>,
Mike Kravetz <mike.kravetz@oracle.com>,
LKML <Linux-kernel@vger.kernel.org>
Subject: Re: [PATCHv2] mm/gup: speed up check_and_migrate_cma_pages() on huge page
Date: Mon, 24 Jun 2019 13:32:34 +0800 [thread overview]
Message-ID: <CAFgQCTuMVdrjkiQ5H3xUuME16g-xNUFXtvU1p+=P4-pujXcSAA@mail.gmail.com> (raw)
In-Reply-To: <20190624044305.GA30102@iweiny-DESK2.sc.intel.com>
On Mon, Jun 24, 2019 at 12:43 PM Ira Weiny <ira.weiny@intel.com> wrote:
>
> On Mon, Jun 24, 2019 at 12:12:41PM +0800, Pingfan Liu wrote:
> > Both hugetlb and thp locate on the same migration type of pageblock, since
> > they are allocated from a free_list[]. Based on this fact, it is enough to
> > check on a single subpage to decide the migration type of the whole huge
> > page. By this way, it saves (2M/4K - 1) times loop for pmd_huge on x86,
> > similar on other archs.
> >
> > Furthermore, when executing isolate_huge_page(), it avoid taking global
> > hugetlb_lock many times, and meanless remove/add to the local link list
> > cma_page_list.
> >
> > Signed-off-by: Pingfan Liu <kernelfans@gmail.com>
> > Cc: Andrew Morton <akpm@linux-foundation.org>
> > Cc: Ira Weiny <ira.weiny@intel.com>
> > Cc: Mike Rapoport <rppt@linux.ibm.com>
> > Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
> > Cc: Thomas Gleixner <tglx@linutronix.de>
> > Cc: John Hubbard <jhubbard@nvidia.com>
> > Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
> > Cc: Christoph Hellwig <hch@lst.de>
> > Cc: Keith Busch <keith.busch@intel.com>
> > Cc: Mike Kravetz <mike.kravetz@oracle.com>
> > Cc: Linux-kernel@vger.kernel.org
> > ---
> > mm/gup.c | 19 ++++++++++++-------
> > 1 file changed, 12 insertions(+), 7 deletions(-)
> >
> > diff --git a/mm/gup.c b/mm/gup.c
> > index ddde097..544f5de 100644
> > --- a/mm/gup.c
> > +++ b/mm/gup.c
> > @@ -1342,19 +1342,22 @@ static long check_and_migrate_cma_pages(struct task_struct *tsk,
> > LIST_HEAD(cma_page_list);
> >
> > check_again:
> > - for (i = 0; i < nr_pages; i++) {
> > + for (i = 0; i < nr_pages;) {
> > +
> > + struct page *head = compound_head(pages[i]);
> > + long step = 1;
> > +
> > + if (PageCompound(head))
> > + step = compound_order(head) - (pages[i] - head);
>
> Sorry if I missed this last time. compound_order() is not correct here.
For thp, prep_transhuge_page()->prep_compound_page()->set_compound_order().
For smaller hugetlb,
prep_new_huge_page()->prep_compound_page()->set_compound_order().
For gigantic page, prep_compound_gigantic_page()->set_compound_order().
Do I miss anything?
Thanks,
Pingfan
[...]
next prev parent reply other threads:[~2019-06-24 5:33 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-06-24 4:12 [PATCHv2] mm/gup: speed up check_and_migrate_cma_pages() on huge page Pingfan Liu
2019-06-24 4:43 ` Ira Weiny
2019-06-24 5:32 ` Pingfan Liu [this message]
2019-06-24 5:34 ` Pingfan Liu
2019-06-24 23:01 ` Ira Weiny
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='CAFgQCTuMVdrjkiQ5H3xUuME16g-xNUFXtvU1p+=P4-pujXcSAA@mail.gmail.com' \
--to=kernelfans@gmail.com \
--cc=Linux-kernel@vger.kernel.org \
--cc=Linux-mm@kvack.org \
--cc=akpm@linux-foundation.org \
--cc=aneesh.kumar@linux.ibm.com \
--cc=hch@lst.de \
--cc=ira.weiny@intel.com \
--cc=jhubbard@nvidia.com \
--cc=keith.busch@intel.com \
--cc=kirill.shutemov@linux.intel.com \
--cc=mike.kravetz@oracle.com \
--cc=rppt@linux.ibm.com \
--cc=tglx@linutronix.de \
/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).