linux-kernel - [PATCH] mm: account NR_WRITTEN at IO completion time

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-ID: <20110713222429.GA14098@localhost>
Date:	Wed, 13 Jul 2011 15:24:29 -0700
From:	Wu Fengguang <fengguang.wu@...el.com>
To:	Andrew Morton <akpm@...ux-foundation.org>
Cc:	Michael Rubin <mrubin@...gle.com>,
	Linux Memory Management List <linux-mm@...ck.org>,
	LKML <linux-kernel@...r.kernel.org>
Subject: [PATCH] mm: account NR_WRITTEN at IO completion time

NR_WRITTEN is now accounted at block IO enqueue time, which is not
very accurate as to common understanding. This moves NR_WRITTEN
accounting to the IO completion time and makes it more consistent
with BDI_WRITTEN, which is used for bandwidth estimation.

CC: Michael Rubin <mrubin@...gle.com>
Signed-off-by: Wu Fengguang <fengguang.wu@...el.com>
---
 mm/page-writeback.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

--- linux-next.orig/mm/page-writeback.c	2011-04-18 17:28:44.000000000 +0800
+++ linux-next/mm/page-writeback.c	2011-04-18 17:30:33.000000000 +0800
@@ -1846,7 +1846,6 @@ EXPORT_SYMBOL(account_page_dirtied);
 void account_page_writeback(struct page *page)
 {
 	inc_zone_page_state(page, NR_WRITEBACK);
-	inc_zone_page_state(page, NR_WRITTEN);
 }
 EXPORT_SYMBOL(account_page_writeback);
 
@@ -2063,8 +2062,10 @@ int test_clear_page_writeback(struct pag
 	} else {
 		ret = TestClearPageWriteback(page);
 	}
-	if (ret)
+	if (ret) {
 		dec_zone_page_state(page, NR_WRITEBACK);
+		inc_zone_page_state(page, NR_WRITTEN);
+	}
 	return ret;
 }
 
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/