[Ocfs2-devel] [PATCH] ocfs2: use find_last_bit

[Ocfs2-devel] [PATCH] ocfs2: use find_last_bit

[Akinobu Mita]

We have find_last_bit() these days.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: ocfs2-devel at oss.oracle.com
---
 fs/ocfs2/cluster/heartbeat.c |   18 ++----------------
 1 files changed, 2 insertions(+), 16 deletions(-)

diff --git a/fs/ocfs2/cluster/heartbeat.c b/fs/ocfs2/cluster/heartbeat.c
index b108e86..e54f665 100644
--- a/fs/ocfs2/cluster/heartbeat.c
+++ b/fs/ocfs2/cluster/heartbeat.c
@@ -924,23 +924,9 @@ out:
 	return changed;
 }
 
-/* This could be faster if we just implmented a find_last_bit, but I
- * don't think the circumstances warrant it. */
-static int o2hb_highest_node(unsigned long *nodes,
-			     int numbits)
+static int o2hb_highest_node(unsigned long *nodes, int numbits)
 {
-	int highest, node;
-
-	highest = numbits;
-	node = -1;
-	while ((node = find_next_bit(nodes, numbits, node + 1)) != -1) {
-		if (node >= numbits)
-			break;
-
-		highest = node;
-	}
-
-	return highest;
+	return find_last_bit(nodes, numbits);
 }
 
 static int o2hb_do_disk_heartbeat(struct o2hb_region *reg)
-- 
1.7.4

[Ocfs2-devel] [PATCH] ocfs2: use find_last_bit

[Akinobu Mita]

We already have find_last_bit. So just use it as described in the comment.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: ocfs2-devel at oss.oracle.com
---
 fs/ocfs2/cluster/heartbeat.c |   18 ++----------------
 1 files changed, 2 insertions(+), 16 deletions(-)

diff --git a/fs/ocfs2/cluster/heartbeat.c b/fs/ocfs2/cluster/heartbeat.c
index cd36cb5..120fad9 100644
--- a/fs/ocfs2/cluster/heartbeat.c
+++ b/fs/ocfs2/cluster/heartbeat.c
@@ -956,23 +956,9 @@ out:
 	return changed;
 }
 
-/* This could be faster if we just implmented a find_last_bit, but I
- * don't think the circumstances warrant it. */
-static int o2hb_highest_node(unsigned long *nodes,
-			     int numbits)
+static int o2hb_highest_node(unsigned long *nodes, int numbits)
 {
-	int highest, node;
-
-	highest = numbits;
-	node = -1;
-	while ((node = find_next_bit(nodes, numbits, node + 1)) != -1) {
-		if (node >= numbits)
-			break;
-
-		highest = node;
-	}
-
-	return highest;
+	return find_last_bit(nodes, numbits);
 }
 
 static int o2hb_do_disk_heartbeat(struct o2hb_region *reg)
-- 
1.7.4.4

[Ocfs2-devel] [PATCH] ocfs2: use bitmap_weight()

[Akinobu Mita]

Use bitmap_weight instead of reinventing the wheel.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: ocfs2-devel at oss.oracle.com
---
 fs/ocfs2/cluster/heartbeat.c |   22 +++++++---------------
 1 files changed, 7 insertions(+), 15 deletions(-)

diff --git a/fs/ocfs2/cluster/heartbeat.c b/fs/ocfs2/cluster/heartbeat.c
index 120fad9..7542566 100644
--- a/fs/ocfs2/cluster/heartbeat.c
+++ b/fs/ocfs2/cluster/heartbeat.c
@@ -35,6 +35,7 @@
 #include <linux/time.h>
 #include <linux/debugfs.h>
 #include <linux/slab.h>
+#include <linux/bitmap.h>
 
 #include "heartbeat.h"
 #include "tcp.h"
@@ -282,15 +283,6 @@ struct o2hb_bio_wait_ctxt {
 	int               wc_error;
 };
 
-static int o2hb_pop_count(void *map, int count)
-{
-	int i = -1, pop = 0;
-
-	while ((i = find_next_bit(map, count, i + 1)) < count)
-		pop++;
-	return pop;
-}
-
 static void o2hb_write_timeout(struct work_struct *work)
 {
 	int failed, quorum;
@@ -307,9 +299,9 @@ static void o2hb_write_timeout(struct work_struct *work)
 		spin_lock_irqsave(&o2hb_live_lock, flags);
 		if (test_bit(reg->hr_region_num, o2hb_quorum_region_bitmap))
 			set_bit(reg->hr_region_num, o2hb_failed_region_bitmap);
-		failed = o2hb_pop_count(&o2hb_failed_region_bitmap,
+		failed = bitmap_weight(o2hb_failed_region_bitmap,
 					O2NM_MAX_REGIONS);
-		quorum = o2hb_pop_count(&o2hb_quorum_region_bitmap,
+		quorum = bitmap_weight(o2hb_quorum_region_bitmap,
 					O2NM_MAX_REGIONS);
 		spin_unlock_irqrestore(&o2hb_live_lock, flags);
 
@@ -771,7 +763,7 @@ static void o2hb_set_quorum_device(struct o2hb_region *reg)
 	 * If global heartbeat active, unpin all regions if the
 	 * region count > CUT_OFF
 	 */
-	if (o2hb_pop_count(&o2hb_quorum_region_bitmap,
+	if (bitmap_weight(o2hb_quorum_region_bitmap,
 			   O2NM_MAX_REGIONS) > O2HB_PIN_CUT_OFF)
 		o2hb_region_unpin(NULL);
 unlock:
@@ -1813,7 +1805,7 @@ static ssize_t o2hb_region_dev_write(struct o2hb_region *reg,
 	live_threshold = O2HB_LIVE_THRESHOLD;
 	if (o2hb_global_heartbeat_active()) {
 		spin_lock(&o2hb_live_lock);
-		if (o2hb_pop_count(&o2hb_region_bitmap, O2NM_MAX_REGIONS) == 1)
+		if (bitmap_weight(o2hb_region_bitmap, O2NM_MAX_REGIONS) == 1)
 			live_threshold <<= 1;
 		spin_unlock(&o2hb_live_lock);
 	}
@@ -2164,7 +2156,7 @@ static void o2hb_heartbeat_group_drop_item(struct config_group *group,
 	if (!o2hb_dependent_users)
 		goto unlock;
 
-	if (o2hb_pop_count(&o2hb_quorum_region_bitmap,
+	if (bitmap_weight(o2hb_quorum_region_bitmap,
 			   O2NM_MAX_REGIONS) <= O2HB_PIN_CUT_OFF)
 		o2hb_region_pin(NULL);
 
@@ -2458,7 +2450,7 @@ static int o2hb_region_inc_user(const char *region_uuid)
 	if (o2hb_dependent_users > 1)
 		goto unlock;
 
-	if (o2hb_pop_count(&o2hb_quorum_region_bitmap,
+	if (bitmap_weight(o2hb_quorum_region_bitmap,
 			   O2NM_MAX_REGIONS) <= O2HB_PIN_CUT_OFF)
 		ret = o2hb_region_pin(NULL);
 
-- 
1.7.4.4