From owner-svn-src-all@FreeBSD.ORG  Tue Jun 28 20:57:55 2011
Return-Path: <owner-svn-src-all@FreeBSD.ORG>
Delivered-To: svn-src-all@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 3260F106566C;
	Tue, 28 Jun 2011 20:57:55 +0000 (UTC)
	(envelope-from trociny@FreeBSD.org)
Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c])
	by mx1.freebsd.org (Postfix) with ESMTP id 227D98FC15;
	Tue, 28 Jun 2011 20:57:55 +0000 (UTC)
Received: from svn.freebsd.org (localhost [127.0.0.1])
	by svn.freebsd.org (8.14.4/8.14.4) with ESMTP id p5SKvtHW065253;
	Tue, 28 Jun 2011 20:57:55 GMT (envelope-from trociny@svn.freebsd.org)
Received: (from trociny@localhost)
	by svn.freebsd.org (8.14.4/8.14.4/Submit) id p5SKvtXX065251;
	Tue, 28 Jun 2011 20:57:55 GMT (envelope-from trociny@svn.freebsd.org)
Message-Id: <201106282057.p5SKvtXX065251@svn.freebsd.org>
From: Mikolaj Golub <trociny@FreeBSD.org>
Date: Tue, 28 Jun 2011 20:57:55 +0000 (UTC)
To: src-committers@freebsd.org, svn-src-all@freebsd.org,
	svn-src-head@freebsd.org
X-SVN-Group: head
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Cc: 
Subject: svn commit: r223654 - head/sbin/hastd
X-BeenThere: svn-src-all@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: "SVN commit messages for the entire src tree \(except for &quot;
	user&quot; and &quot; projects&quot; \)" <svn-src-all.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-all>,
	<mailto:svn-src-all-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-all>
List-Post: <mailto:svn-src-all@freebsd.org>
List-Help: <mailto:svn-src-all-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-all>,
	<mailto:svn-src-all-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 28 Jun 2011 20:57:55 -0000

Author: trociny
Date: Tue Jun 28 20:57:54 2011
New Revision: 223654
URL: http://svn.freebsd.org/changeset/base/223654

Log:
  Make activemap_write_start/complete check the keepdirty list, when
  stating if we need to update activemap on disk. This makes keepdirty
  serve its purpose -- to reduce number of metadata updates.
  
  Discussed with:	pjd
  Approved by:	pjd (mentor)

Modified:
  head/sbin/hastd/activemap.c

Modified: head/sbin/hastd/activemap.c
==============================================================================
--- head/sbin/hastd/activemap.c	Tue Jun 28 20:28:11 2011	(r223653)
+++ head/sbin/hastd/activemap.c	Tue Jun 28 20:57:54 2011	(r223654)
@@ -205,7 +205,7 @@ keepdirty_find(struct activemap *amp, in
 	return (kd);
 }
 
-static void
+static bool
 keepdirty_add(struct activemap *amp, int extent)
 {
 	struct keepdirty *kd;
@@ -217,7 +217,7 @@ keepdirty_add(struct activemap *amp, int
 		 */
 		TAILQ_REMOVE(&amp->am_keepdirty, kd, kd_next);
 		TAILQ_INSERT_HEAD(&amp->am_keepdirty, kd, kd_next);
-		return;
+		return (false);
 	}
 	/*
 	 * Add new element, but first remove the most unused one if
@@ -238,6 +238,8 @@ keepdirty_add(struct activemap *amp, int
 		amp->am_nkeepdirty++;
 		TAILQ_INSERT_HEAD(&amp->am_keepdirty, kd, kd_next);
 	}
+
+	return (true);
 }
 
 static void
@@ -308,9 +310,9 @@ activemap_write_start(struct activemap *
 			assert(!bit_test(amp->am_memmap, ext));
 			bit_set(amp->am_memmap, ext);
 			amp->am_ndirty++;
-			modified = true;
 		}
-		keepdirty_add(amp, ext);
+		if (keepdirty_add(amp, ext))
+			modified = true;
 	}
 
 	return (modified);
@@ -345,7 +347,8 @@ activemap_write_complete(struct activema
 		if (--amp->am_memtab[ext] == 0) {
 			bit_clear(amp->am_memmap, ext);
 			amp->am_ndirty--;
-			modified = true;
+			if (keepdirty_find(amp, ext) == NULL)
+				modified = true;
 		}
 	}