Enhanced partition statistics: update partition statitics

diff -urNp -X linux-2.6/Documentation/dontdiff linux-2.6.orig/block/ll_rw_blk.c linux-2.6/block/ll_rw_blk.c
@@ -2734,10 +2734,15 @@ 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++;
+		}
 	}
 }
 

@@ -2789,6 +2794,21 @@ 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
  */

@@ -2903,8 +2923,14 @@ 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);

@@ -3447,7 +3473,8 @@ 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;

@@ -3676,11 +3703,16 @@ void end_that_request_last(struct reques
 	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)
 		req->end_io(req, error);

diff -urNp -X linux-2.6/Documentation/dontdiff linux-2.6.orig/fs/partitions/check.c linux-2.6/fs/partitions/check.c
@@ -18,6 +18,7 @@
 #include <linux/fs.h>
 #include <linux/kmod.h>
 #include <linux/ctype.h>
+#include <linux/genhd.h>
 
 #include "check.h"
 

@@ -321,6 +322,7 @@ extern struct kset block_subsys;
 static void part_release(struct kobject *kobj)
 {
 	struct hd_struct * p = container_of(kobj,struct hd_struct,kobj);
+	free_part_stats(p);
 	kfree(p);
 }
 

@@ -361,6 +363,7 @@ 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);
 	sysfs_remove_link(&p->kobj, "subsystem");
 	kobject_unregister(p->holder_dir);
 	kobject_uevent(&p->kobj, KOBJ_REMOVE);

@@ -376,6 +379,10 @@ 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 -urNp -X linux-2.6/Documentation/dontdiff linux-2.6.orig/include/linux/genhd.h linux-2.6/include/linux/genhd.h
@@ -359,6 +359,7 @@ 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);