From: Nai Xia <nai.xia@gmail.com>
To: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>, Mel Gorman <mgorman@suse.de>,
Pawel Sikora <pluto@agmk.net>,
Andrew Morton <akpm@linux-foundation.org>,
linux-mm@kvack.org, jpiszcz@lucidpixels.com, arekm@pld-linux.org,
linux-kernel@vger.kernel.org
Subject: [PATCH] mremap: skip page table lookup for non-faulted anonymous VMAs
Date: Mon, 7 Nov 2011 12:21:35 +0800 [thread overview]
Message-ID: <201111071221.35403.nai.xia@gmail.com> (raw)
If an anonymous vma has not yet been faulted, move_page_tables() in move_vma()
is not necessary for it.
Signed-off-by: Nai Xia <nai.xia@gmail.com>
---
diff --git a/mm/mremap.c b/mm/mremap.c
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -200,6 +200,10 @@ static unsigned long move_vma(struct vm_area_struct *vma,
if (!new_vma)
return -ENOMEM;
+ /* An anonymous vma has not been faulted, no pagetables lookup. */
+ if (!vma->vm_file && !vma->anon_vma)
+ goto page_tables_ok;
+
moved_len = move_page_tables(vma, old_addr, new_vma, new_addr, old_len);
if (moved_len < old_len) {
/*
@@ -213,6 +217,7 @@ static unsigned long move_vma(struct vm_area_struct *vma,
old_addr = new_addr;
new_addr = -ENOMEM;
}
+page_tables_ok:
/* Conceal VM_ACCOUNT so old reservation is not undone */
if (vm_flags & VM_ACCOUNT) {
WARNING: multiple messages have this Message-ID (diff)
From: Nai Xia <nai.xia@gmail.com>
To: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>, Mel Gorman <mgorman@suse.de>,
Pawel Sikora <pluto@agmk.net>,
Andrew Morton <akpm@linux-foundation.org>,
linux-mm@kvack.org, jpiszcz@lucidpixels.com, arekm@pld-linux.org,
linux-kernel@vger.kernel.org
Subject: [PATCH] mremap: skip page table lookup for non-faulted anonymous VMAs
Date: Mon, 7 Nov 2011 12:21:35 +0800 [thread overview]
Message-ID: <201111071221.35403.nai.xia@gmail.com> (raw)
If an anonymous vma has not yet been faulted, move_page_tables() in move_vma()
is not necessary for it.
Signed-off-by: Nai Xia <nai.xia@gmail.com>
---
diff --git a/mm/mremap.c b/mm/mremap.c
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -200,6 +200,10 @@ static unsigned long move_vma(struct vm_area_struct *vma,
if (!new_vma)
return -ENOMEM;
+ /* An anonymous vma has not been faulted, no pagetables lookup. */
+ if (!vma->vm_file && !vma->anon_vma)
+ goto page_tables_ok;
+
moved_len = move_page_tables(vma, old_addr, new_vma, new_addr, old_len);
if (moved_len < old_len) {
/*
@@ -213,6 +217,7 @@ static unsigned long move_vma(struct vm_area_struct *vma,
old_addr = new_addr;
new_addr = -ENOMEM;
}
+page_tables_ok:
/* Conceal VM_ACCOUNT so old reservation is not undone */
if (vm_flags & VM_ACCOUNT) {
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next reply other threads:[~2011-11-07 4:22 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-11-07 4:21 Nai Xia [this message]
2011-11-07 4:21 ` [PATCH] mremap: skip page table lookup for non-faulted anonymous VMAs Nai Xia
2011-11-07 15:32 ` Andrea Arcangeli
2011-11-07 15:32 ` Andrea Arcangeli
2011-11-07 16:13 ` Nai Xia
2011-11-07 16:13 ` Nai Xia
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=201111071221.35403.nai.xia@gmail.com \
--to=nai.xia@gmail.com \
--cc=aarcange@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=arekm@pld-linux.org \
--cc=hughd@google.com \
--cc=jpiszcz@lucidpixels.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mgorman@suse.de \
--cc=pluto@agmk.net \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.