LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Baolin Wang <baolin.wang@linux.alibaba.com>
To: akpm@linux-foundation.org
Cc: baolin.wang@linux.alibaba.com, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH 1/5] mm: migrate: Move the page count validation to the proper place
Date: Thu,  5 Aug 2021 23:05:56 +0800	[thread overview]
Message-ID: <1f7e1d083864fbb17a20a9c8349d2e8b427e20a3.1628174413.git.baolin.wang@linux.alibaba.com> (raw)
In-Reply-To: <cover.1628174413.git.baolin.wang@linux.alibaba.com>
In-Reply-To: <cover.1628174413.git.baolin.wang@linux.alibaba.com>

We've got the expected count for anonymous page or file page by
expected_page_refs() at the beginning of migrate_page_move_mapping(),
thus we should move the page count validation a little forward to
reduce duplicated code.

Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
---
 mm/migrate.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/mm/migrate.c b/mm/migrate.c
index 239b238..5559571 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -386,11 +386,10 @@ int folio_migrate_mapping(struct address_space *mapping,
 	int expected_count = expected_page_refs(mapping, &folio->page) + extra_count;
 	long nr = folio_nr_pages(folio);
 
-	if (!mapping) {
-		/* Anonymous page without mapping */
-		if (folio_ref_count(folio) != expected_count)
-			return -EAGAIN;
+	if (folio_ref_count(folio) != expected_count)
+		return -EAGAIN;
 
+	if (!mapping) {
 		/* No turning back from here */
 		newfolio->index = folio->index;
 		newfolio->mapping = folio->mapping;
@@ -404,8 +403,7 @@ int folio_migrate_mapping(struct address_space *mapping,
 	newzone = folio_zone(newfolio);
 
 	xas_lock_irq(&xas);
-	if (folio_ref_count(folio) != expected_count ||
-	    xas_load(&xas) != folio) {
+	if (xas_load(&xas) != folio) {
 		xas_unlock_irq(&xas);
 		return -EAGAIN;
 	}
-- 
1.8.3.1


  reply	other threads:[~2021-08-05 15:06 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-05 15:05 [PATCH 0/5] Some cleanup for page migration Baolin Wang
2021-08-05 15:05 ` Baolin Wang [this message]
2021-08-05 15:17   ` [PATCH 1/5] mm: migrate: Move the page count validation to the proper place Matthew Wilcox
2021-08-06  3:07     ` Baolin Wang
2021-08-07  2:02       ` Matthew Wilcox
2021-08-08  2:55         ` Baolin Wang
2021-08-08 10:26           ` Matthew Wilcox
2021-08-08 15:13             ` Baolin Wang
2021-08-08 16:01               ` Matthew Wilcox
2021-08-09  4:19                 ` Baolin Wang
2021-08-05 15:05 ` [PATCH 2/5] mm: migrate: Introduce a local variable to get the number of pages Baolin Wang
2021-08-05 17:42   ` Yang Shi
2021-08-05 15:05 ` [PATCH 3/5] mm: migrate: Fix the incorrect function name in comments Baolin Wang
2021-08-05 17:26   ` Yang Shi
2021-08-09 13:59   ` Alistair Popple
2021-08-05 15:05 ` [PATCH 4/5] mm: migrate: Change to use bool type for 'page_was_mapped' Baolin Wang
2021-08-05 17:34   ` Yang Shi
2021-08-05 15:06 ` [PATCH 5/5] mm: migrate: Remove redundant goto labels Baolin Wang
2021-08-05 19:54   ` Yang Shi
2021-08-06  3:20     ` Baolin Wang
2021-08-06 17:17       ` Yang Shi
2021-08-08  2:56         ` Baolin Wang

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=1f7e1d083864fbb17a20a9c8349d2e8b427e20a3.1628174413.git.baolin.wang@linux.alibaba.com \
    --to=baolin.wang@linux.alibaba.com \
    --cc=akpm@linux-foundation.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --subject='Re: [PATCH 1/5] mm: migrate: Move the page count validation to the proper place' \
    /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

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).