From 074a7aca7afa6f230104e8e65eba3420263714a5 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 25 Aug 2008 19:56:14 +0900 Subject: block: move stats from disk to part0 Move stats related fields - stamp, in_flight, dkstats - from disk to part0 and unify stat handling such that... * part_stat_*() now updates part0 together if the specified partition is not part0. ie. part_stat_*() are now essentially all_stat_*(). * {disk|all}_stat_*() are gone. * part_round_stats() is updated similary. It handles part0 stats automatically and disk_round_stats() is killed. * part_{inc|dec}_in_fligh() is implemented which automatically updates part0 stats for parts other than part0. * disk_map_sector_rcu() is updated to return part0 if no part matches. Combined with the above changes, this makes NULL special case handling in callers unnecessary. * Separate stats show code paths for disk are collapsed into part stats show code paths. * Rename disk_stat_lock/unlock() to part_stat_lock/unlock() While at it, reposition stat handling macros a bit and add missing parentheses around macro parameters. Signed-off-by: Tejun Heo Signed-off-by: Jens Axboe --- block/blk-core.c | 84 +++++++++++++++++++++++--------------------------------- 1 file changed, 34 insertions(+), 50 deletions(-) (limited to 'block/blk-core.c') diff --git a/block/blk-core.c b/block/blk-core.c index 505ec61067d..98138f00252 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -61,21 +61,17 @@ static void drive_stat_acct(struct request *rq, int new_io) if (!blk_fs_request(rq) || !rq->rq_disk) return; - cpu = disk_stat_lock(); + cpu = part_stat_lock(); part = disk_map_sector_rcu(rq->rq_disk, rq->sector); if (!new_io) - all_stat_inc(cpu, rq->rq_disk, part, merges[rw], rq->sector); + part_stat_inc(cpu, part, merges[rw]); else { - disk_round_stats(cpu, rq->rq_disk); - rq->rq_disk->in_flight++; - if (part) { - part_round_stats(cpu, part); - part->in_flight++; - } + part_round_stats(cpu, part); + part_inc_in_flight(part); } - disk_stat_unlock(); + part_stat_unlock(); } void blk_queue_congestion_threshold(struct request_queue *q) @@ -983,8 +979,22 @@ static inline void add_request(struct request_queue *q, struct request *req) __elv_add_request(q, req, ELEVATOR_INSERT_SORT, 0); } -/* - * disk_round_stats() - Round off the performance stats on a struct +static void part_round_stats_single(int cpu, struct hd_struct *part, + unsigned long now) +{ + if (now == part->stamp) + return; + + if (part->in_flight) { + __part_stat_add(cpu, part, time_in_queue, + part->in_flight * (now - part->stamp)); + __part_stat_add(cpu, part, io_ticks, (now - part->stamp)); + } + part->stamp = now; +} + +/** + * part_round_stats() - Round off the performance stats on a struct * disk_stats. * * The average IO queue length and utilisation statistics are maintained @@ -998,36 +1008,15 @@ static inline void add_request(struct request_queue *q, struct request *req) * /proc/diskstats. This accounts immediately for all queue usage up to * the current jiffies and restarts the counters again. */ -void disk_round_stats(int cpu, struct gendisk *disk) -{ - unsigned long now = jiffies; - - if (now == disk->stamp) - return; - - if (disk->in_flight) { - disk_stat_add(cpu, disk, time_in_queue, - disk->in_flight * (now - disk->stamp)); - disk_stat_add(cpu, disk, io_ticks, (now - disk->stamp)); - } - disk->stamp = now; -} -EXPORT_SYMBOL_GPL(disk_round_stats); - void part_round_stats(int cpu, struct hd_struct *part) { unsigned long now = jiffies; - if (now == part->stamp) - return; - - if (part->in_flight) { - part_stat_add(cpu, part, time_in_queue, - part->in_flight * (now - part->stamp)); - part_stat_add(cpu, part, io_ticks, (now - part->stamp)); - } - part->stamp = now; + if (part->partno) + part_round_stats_single(cpu, &part_to_disk(part)->part0, now); + part_round_stats_single(cpu, part, now); } +EXPORT_SYMBOL_GPL(part_round_stats); /* * queue lock must be held @@ -1567,11 +1556,10 @@ static int __end_that_request_first(struct request *req, int error, struct hd_struct *part; int cpu; - cpu = disk_stat_lock(); + cpu = part_stat_lock(); part = disk_map_sector_rcu(req->rq_disk, req->sector); - all_stat_add(cpu, req->rq_disk, part, sectors[rw], - nr_bytes >> 9, req->sector); - disk_stat_unlock(); + part_stat_add(cpu, part, sectors[rw], nr_bytes >> 9); + part_stat_unlock(); } total_bytes = bio_nbytes = 0; @@ -1758,19 +1746,15 @@ static void end_that_request_last(struct request *req, int error) struct hd_struct *part; int cpu; - cpu = disk_stat_lock(); + cpu = part_stat_lock(); part = disk_map_sector_rcu(disk, req->sector); - all_stat_inc(cpu, disk, part, ios[rw], req->sector); - all_stat_add(cpu, disk, part, ticks[rw], duration, req->sector); - disk_round_stats(cpu, disk); - disk->in_flight--; - if (part) { - part_round_stats(cpu, part); - part->in_flight--; - } + part_stat_inc(cpu, part, ios[rw]); + part_stat_add(cpu, part, ticks[rw], duration); + part_round_stats(cpu, part); + part_dec_in_flight(part); - disk_stat_unlock(); + part_stat_unlock(); } if (req->end_io) -- cgit v1.2.3