[PATCH 3/5] pktcdvd: More accurate I/O accounting

Peter Osterlund
2005-09-11T16:45:05Z

In the /proc statistics, only count writes that upper layers have
requested. Don't count additional writes created inside the packet
driver to satisfy the requirement to only write full packets.

Signed-off-by: Peter Osterlund <petero2@telia.com>
---

drivers/block/pktcdvd.c | 14 +++++++-------
1 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -736,12 +736,6 @@ static void pkt_gather_data(struct pktcd
atomic_set(&pkt->io_wait, 0);
atomic_set(&pkt->io_errors, 0);

- if (pkt->cache_valid) {
- VPRINTK("pkt_gather_data: zone %llx cached\n",
- (unsigned long long)pkt->sector);
- goto out_account;
- }
-
/*
* Figure out which frames we need to read before we can write.
*/
@@ -750,6 +744,7 @@ static void pkt_gather_data(struct pktcd
for (bio = pkt->orig_bios; bio; bio = bio->bi_next) {
int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
int num_frames = bio->bi_size / CD_FRAMESIZE;
+ pd->stats.secs_w += num_frames * (CD_FRAMESIZE >> 9);
BUG_ON(first_frame < 0);
BUG_ON(first_frame + num_frames > pkt->frames);
for (f = first_frame; f < first_frame + num_frames; f++)
@@ -757,6 +752,12 @@ static void pkt_gather_data(struct pktcd
}
spin_unlock(&pkt->lock);

+ if (pkt->cache_valid) {
+ VPRINTK("pkt_gather_data: zone %llx cached\n",
+ (unsigned long long)pkt->sector);
+ goto out_account;
+ }
+
/*
* Schedule reads for missing parts of the packet.
*/
@@ -790,7 +791,6 @@ out_account:
frames_read, (unsigned long long)pkt->sector);
pd->stats.pkt_started++;
pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
- pd->stats.secs_w += pd->settings.size;