[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <7ae64b5e-79ee-5768-34a3-75e33ea45246@infradead.org>
Date: Tue, 17 Apr 2018 14:12:05 -0700
From: Randy Dunlap <rdunlap@...radead.org>
To: "Huang, Ying" <ying.huang@...el.com>,
Andrew Morton <akpm@...ux-foundation.org>
Cc: Tim Chen <tim.c.chen@...el.com>, Andi Kleen <ak@...ux.intel.com>,
linux-mm@...ck.org, linux-kernel@...r.kernel.org,
"Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>,
Andrea Arcangeli <aarcange@...hat.com>,
Michal Hocko <mhocko@...e.com>,
Johannes Weiner <hannes@...xchg.org>,
Shaohua Li <shli@...nel.org>, Hugh Dickins <hughd@...gle.com>,
Minchan Kim <minchan@...nel.org>,
Rik van Riel <riel@...hat.com>,
Dave Hansen <dave.hansen@...ux.intel.com>,
Naoya Horiguchi <n-horiguchi@...jp.nec.com>,
Zi Yan <zi.yan@...rutgers.edu>
Subject: Re: [PATCH -mm 06/21] mm, THP, swap: Support PMD swap mapping when
splitting huge PMD
On 04/16/18 19:02, Huang, Ying wrote:
> From: Huang Ying <ying.huang@...el.com>
>
> A huge PMD need to be split when zap a part of the PMD mapping etc.
> If the PMD mapping is a swap mapping, we need to split it too. This
> patch implemented the support for this. This is similar as splitting
> the PMD page mapping, except we need to decrease the PMD swap mapping
> count for the huge swap cluster too. If the PMD swap mapping count
> becomes 0, the huge swap cluster will be split.
>
> Notice: is_huge_zero_pmd() and pmd_page() doesn't work well with swap
> PMD, so pmd_present() check is called before them.
FWIW, I would prefer to see that comment in the source code, not just
in the commit description.
>
> Signed-off-by: "Huang, Ying" <ying.huang@...el.com>
> Cc: "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>
> Cc: Andrea Arcangeli <aarcange@...hat.com>
> Cc: Michal Hocko <mhocko@...e.com>
> Cc: Johannes Weiner <hannes@...xchg.org>
> Cc: Shaohua Li <shli@...nel.org>
> Cc: Hugh Dickins <hughd@...gle.com>
> Cc: Minchan Kim <minchan@...nel.org>
> Cc: Rik van Riel <riel@...hat.com>
> Cc: Dave Hansen <dave.hansen@...ux.intel.com>
> Cc: Naoya Horiguchi <n-horiguchi@...jp.nec.com>
> Cc: Zi Yan <zi.yan@...rutgers.edu>
> ---
> include/linux/swap.h | 6 +++++
> mm/huge_memory.c | 54 ++++++++++++++++++++++++++++++++++++++++----
> mm/swapfile.c | 28 +++++++++++++++++++++++
> 3 files changed, 83 insertions(+), 5 deletions(-)
--
~Randy
Powered by blists - more mailing lists