linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Yang Shi <yang.shi@linux.alibaba.com>
To: hughd@google.com, kirill.shutemov@linux.intel.com,
	vbabka@suse.cz, akpm@linux-foundation.org
Cc: yang.shi@linux.alibaba.com, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org
Subject: [v2 PATCH 1/2] mm: thp: register mm for khugepaged when merging vma for shmem
Date: Fri, 22 Jun 2018 07:15:48 +0800	[thread overview]
Message-ID: <1529622949-75504-1-git-send-email-yang.shi@linux.alibaba.com> (raw)

When merging anonymous page vma, if the size of vma can fit in at least
one hugepage, the mm will be registered for khugepaged for collapsing
THP in the future.

But, it skips shmem vma. Doing so for shmem too, but not file-private
mapping, when merging vma in order to increase the odd to collapse
hugepage by khugepaged.

Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
---
v1 --> 2:
* Exclude file-private mapping per Kirill's comment

 mm/khugepaged.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index d7b2a4b..9b0ec30 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -440,8 +440,12 @@ int khugepaged_enter_vma_merge(struct vm_area_struct *vma,
 		 * page fault if needed.
 		 */
 		return 0;
-	if (vma->vm_ops || (vm_flags & VM_NO_KHUGEPAGED))
-		/* khugepaged not yet working on file or special mappings */
+	if ((vma->vm_ops && (!shmem_file(vma->vm_file) || vma->anon_vma)) ||
+	    (vm_flags & VM_NO_KHUGEPAGED))
+		/*
+		 * khugepaged not yet working on non-shmem file or special
+		 * mappings. And, file-private shmem THP is not supported.
+		 */
 		return 0;
 	hstart = (vma->vm_start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK;
 	hend = vma->vm_end & HPAGE_PMD_MASK;
-- 
1.8.3.1


             reply	other threads:[~2018-06-21 23:16 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-06-21 23:15 Yang Shi [this message]
2018-06-21 23:15 ` [v2 PATCH 2/2] mm: thp: inc counter for collapsed shmem THP Yang Shi
2018-06-22  8:00   ` Kirill A. Shutemov
2018-06-22  7:59 ` [v2 PATCH 1/2] mm: thp: register mm for khugepaged when merging vma for shmem Kirill A. Shutemov
2018-06-22 16:04   ` Yang Shi
2018-06-22 16:19     ` Kirill A. Shutemov
2018-06-22 16:44       ` Yang Shi

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=1529622949-75504-1-git-send-email-yang.shi@linux.alibaba.com \
    --to=yang.shi@linux.alibaba.com \
    --cc=akpm@linux-foundation.org \
    --cc=hughd@google.com \
    --cc=kirill.shutemov@linux.intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=vbabka@suse.cz \
    /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).