[Patch 2/6] Enhanced partition statistics: update partition statitics

[Jerome Marchand <jmarchan@redhat.com>]

Updates the enhanced partition statistics in generic block layer
besides the disk statistics.

Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
---
 block/blk-core.c      |   34 ++++++++++++++++++++++++++++++----
 block/blk-merge.c     |    6 ++++++
 fs/partitions/check.c |    7 +++++++
 include/linux/genhd.h |    1 +
 4 files changed, 44 insertions(+), 4 deletions(-)
diff -uprN -X linux-2.6/Documentation/dontdiff linux-2.6.orig/block/blk-core.c linux-2.6/block/blk-core.c
--- linux-2.6.orig/block/blk-core.c	2008-01-31 16:44:09.000000000 +0100
+++ linux-2.6/block/blk-core.c	2008-01-31 17:31:26.000000000 +0100
@@ -59,10 +59,15 @@ static void drive_stat_acct(struct reque
 		return;
 
 	if (!new_io) {
-		__disk_stat_inc(rq->rq_disk, merges[rw]);
+		__all_stat_inc(rq->rq_disk, merges[rw], rq->sector);
 	} else {
+		struct hd_struct *part = get_part(rq->rq_disk, rq->sector);
 		disk_round_stats(rq->rq_disk);
 		rq->rq_disk->in_flight++;
+		if (part) {
+			part_round_stats(part);
+			part->in_flight++;
+		}
 	}
 }
 
@@ -990,6 +995,21 @@ void disk_round_stats(struct gendisk *di
 
 EXPORT_SYMBOL_GPL(disk_round_stats);
 
+void part_round_stats(struct hd_struct *part)
+{
+	unsigned long now = jiffies;
+
+	if (now == part->stamp)
+		return;
+
+	if (part->in_flight) {
+		__part_stat_add(part, time_in_queue,
+				part->in_flight * (now - part->stamp));
+		__part_stat_add(part, io_ticks, (now - part->stamp));
+	}
+	part->stamp = now;
+}
+
 /*
  * queue lock must be held
  */
@@ -1528,7 +1548,8 @@ static int __end_that_request_first(stru
 	if (blk_fs_request(req) && req->rq_disk) {
 		const int rw = rq_data_dir(req);
 
-		disk_stat_add(req->rq_disk, sectors[rw], nr_bytes >> 9);
+		all_stat_add(req->rq_disk, sectors[rw],
+			     nr_bytes >> 9, req->sector);
 	}
 
 	total_bytes = bio_nbytes = 0;
@@ -1712,11 +1733,16 @@ static void end_that_request_last(struct
 	if (disk && blk_fs_request(req) && req != &req->q->bar_rq) {
 		unsigned long duration = jiffies - req->start_time;
 		const int rw = rq_data_dir(req);
+		struct hd_struct *part = get_part(disk, req->sector);
 
-		__disk_stat_inc(disk, ios[rw]);
-		__disk_stat_add(disk, ticks[rw], duration);
+		__all_stat_inc(disk, ios[rw], req->sector);
+		__all_stat_add(disk, ticks[rw], duration, req->sector);
 		disk_round_stats(disk);
 		disk->in_flight--;
+		if (part) {
+			part_round_stats(part);
+			part->in_flight--;
+		}
 	}
 
 	if (req->end_io)
diff -uprN -X linux-2.6/Documentation/dontdiff linux-2.6.orig/block/blk-merge.c linux-2.6/block/blk-merge.c
--- linux-2.6.orig/block/blk-merge.c	2008-01-31 16:44:09.000000000 +0100
+++ linux-2.6/block/blk-merge.c	2008-01-31 17:36:44.000000000 +0100
@@ -454,8 +454,14 @@ static int attempt_merge(struct request_
 	elv_merge_requests(q, req, next);
 
 	if (req->rq_disk) {
+		struct hd_struct *part
+			= get_part(req->rq_disk, req->sector);
 		disk_round_stats(req->rq_disk);
 		req->rq_disk->in_flight--;
+		if (part) {
+			part_round_stats(part);
+			part->in_flight--;
+		}
 	}
 
 	req->ioprio = ioprio_best(req->ioprio, next->ioprio);
diff -uprN -X linux-2.6/Documentation/dontdiff linux-2.6.orig/fs/partitions/check.c linux-2.6/fs/partitions/check.c
--- linux-2.6.orig/fs/partitions/check.c	2008-01-31 16:42:56.000000000 +0100
+++ linux-2.6/fs/partitions/check.c	2008-01-31 17:31:26.000000000 +0100
@@ -18,6 +18,7 @@
 #include <linux/fs.h>
 #include <linux/kmod.h>
 #include <linux/ctype.h>
+#include <linux/genhd.h>
 
 #include "check.h"
 
@@ -273,6 +274,7 @@ static struct attribute_group *part_attr
 static void part_release(struct device *dev)
 {
 	struct hd_struct *p = dev_to_part(dev);
+	free_part_stats(p);
 	kfree(p);
 }
 
@@ -314,6 +316,7 @@ void delete_partition(struct gendisk *di
 	p->nr_sects = 0;
 	p->ios[0] = p->ios[1] = 0;
 	p->sectors[0] = p->sectors[1] = 0;
+	part_stat_set_all(p, 0);
 	kobject_put(p->holder_dir);
 	device_del(&p->dev);
 	put_device(&p->dev);
@@ -328,6 +331,10 @@ void add_partition(struct gendisk *disk,
 	if (!p)
 		return;
 
+	if (!init_part_stats(p)) {
+		kfree(p);
+		return;
+	}
 	p->start_sect = start;
 	p->nr_sects = len;
 	p->partno = part;
diff -uprN -X linux-2.6/Documentation/dontdiff linux-2.6.orig/include/linux/genhd.h linux-2.6/include/linux/genhd.h
--- linux-2.6.orig/include/linux/genhd.h	2008-01-31 17:00:48.000000000 +0100
+++ linux-2.6/include/linux/genhd.h	2008-01-31 17:30:36.000000000 +0100
@@ -364,6 +364,7 @@ static inline void free_part_stats(struc
 
 /* drivers/block/ll_rw_blk.c */
 extern void disk_round_stats(struct gendisk *disk);
+extern void part_round_stats(struct hd_struct *part);
 
 /* drivers/block/genhd.c */
 extern int get_blkdev_list(char *, int);