From: Nick Piggin <piggin@cyberone.com.au>
To: "Prakash K. Cheemplavam" <prakashpublic@gmx.de>
Cc: linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: 2.9test9-mm1 and DAO ATAPI cd-burning corrupt
Date: Sat, 08 Nov 2003 00:03:19 +1100 [thread overview]
Message-ID: <3FAB9817.5020502@cyberone.com.au> (raw)
In-Reply-To: <3FAB95B9.3020601@gmx.de>
[-- Attachment #1: Type: text/plain, Size: 444 bytes --]
Prakash K. Cheemplavam wrote:
>
> Yes, with this patch, it seems to be like in mm1 again, no more
> stuttering (or at least I can't notice it anymore, as since 2 daysI
> have an LCD), but also the bad stuttering at erase and burn start are
> gone again. So do you have an idea what causes the problem?
>
Getting there, thanks for testing. We'll take the others off the CC
list: the problem is not in Linus' tree. Please try this patch.
[-- Attachment #2: as-revert2.patch --]
[-- Type: text/plain, Size: 11285 bytes --]
linux-2.6-npiggin/drivers/block/as-iosched.c | 219 +++++++++------------------
1 files changed, 78 insertions(+), 141 deletions(-)
diff -puN drivers/block/as-iosched.c~as-revert2 drivers/block/as-iosched.c
--- linux-2.6/drivers/block/as-iosched.c~as-revert2 2003-11-07 23:59:20.000000000 +1100
+++ linux-2.6-npiggin/drivers/block/as-iosched.c 2003-11-08 00:00:25.000000000 +1100
@@ -70,7 +70,6 @@
/* Bits in as_io_context.state */
enum as_io_states {
AS_TASK_RUNNING=0, /* Process has not exitted */
- AS_TASK_IOSTARTED, /* Process has started some IO */
AS_TASK_IORUNNING, /* Process has completed some IO */
};
@@ -100,14 +99,6 @@ struct as_data {
sector_t last_sector[2]; /* last REQ_SYNC & REQ_ASYNC sectors */
struct list_head *dispatch; /* driver dispatch queue */
struct list_head *hash; /* request hash */
-
- unsigned long exit_prob; /* probability a task will exit while
- being waited on */
- unsigned long new_ttime_total; /* mean thinktime on new proc */
- unsigned long new_ttime_mean;
- u64 new_seek_total; /* mean seek on new proc */
- sector_t new_seek_mean;
-
unsigned long current_batch_expires;
unsigned long last_check_fifo[2];
int changed_batch; /* 1: waiting for old batch to end */
@@ -195,7 +186,6 @@ static void free_as_io_context(struct as
/* Called when the task exits */
static void exit_as_io_context(struct as_io_context *aic)
{
- WARN_ON(!test_bit(AS_TASK_RUNNING, &aic->state));
clear_bit(AS_TASK_RUNNING, &aic->state);
}
@@ -618,15 +608,8 @@ static void as_antic_timeout(unsigned lo
spin_lock_irqsave(q->queue_lock, flags);
if (ad->antic_status == ANTIC_WAIT_REQ
|| ad->antic_status == ANTIC_WAIT_NEXT) {
- struct as_io_context *aic = ad->io_context->aic;
-
ad->antic_status = ANTIC_FINISHED;
kblockd_schedule_work(&ad->antic_work);
-
- if (aic->ttime_samples == 0) {
- /* process anticipated on has exitted or timed out*/
- ad->exit_prob = (7*ad->exit_prob + 256)/8;
- }
}
spin_unlock_irqrestore(q->queue_lock, flags);
}
@@ -640,7 +623,7 @@ static int as_close_req(struct as_data *
unsigned long delay; /* milliseconds */
sector_t last = ad->last_sector[ad->batch_data_dir];
sector_t next = arq->request->sector;
- sector_t delta; /* acceptable close offset (in sectors) */
+ sector_t delta; /* acceptable close offset (in sectors) */
if (ad->antic_status == ANTIC_OFF || !ad->ioc_finished)
delay = 0;
@@ -657,7 +640,6 @@ static int as_close_req(struct as_data *
return (last - (delta>>1) <= next) && (next <= last + delta);
}
-static void as_update_thinktime(struct as_data *ad, struct as_io_context *aic, unsigned long ttime);
/*
* as_can_break_anticipation returns true if we have been anticipating this
* request.
@@ -675,27 +657,9 @@ static int as_can_break_anticipation(str
{
struct io_context *ioc;
struct as_io_context *aic;
- sector_t s;
-
- ioc = ad->io_context;
- BUG_ON(!ioc);
-
- if (arq && ioc == arq->io_context) {
- /* request from same process */
- return 1;
- }
if (arq && arq->is_sync == REQ_SYNC && as_close_req(ad, arq)) {
/* close request */
- struct as_io_context *aic = ioc->aic;
- if (aic) {
- unsigned long thinktime;
- spin_lock(&aic->lock);
- thinktime = jiffies - aic->last_end_request;
- aic->last_end_request = jiffies;
- as_update_thinktime(ad, aic, thinktime);
- spin_unlock(&aic->lock);
- }
return 1;
}
@@ -707,14 +671,20 @@ static int as_can_break_anticipation(str
return 1;
}
+ ioc = ad->io_context;
+ BUG_ON(!ioc);
+
+ if (arq && ioc == arq->io_context) {
+ /* request from same process */
+ return 1;
+ }
+
aic = ioc->aic;
if (!aic)
return 0;
if (!test_bit(AS_TASK_RUNNING, &aic->state)) {
/* process anticipated on has exitted */
- if (aic->ttime_samples == 0)
- ad->exit_prob = (7*ad->exit_prob + 256)/8;
return 1;
}
@@ -728,36 +698,27 @@ static int as_can_break_anticipation(str
return 1;
}
- if (aic->ttime_samples == 0) {
- if (ad->new_ttime_mean > ad->antic_expire)
- return 1;
- if (ad->exit_prob > 128)
- return 1;
- } else if (aic->ttime_mean > ad->antic_expire) {
- /* the process thinks too much between requests */
+ if (aic->seek_samples == 0 || aic->ttime_samples == 0) {
+ /*
+ * Process has just started IO. Don't anticipate.
+ * TODO! Must fix this up.
+ */
return 1;
}
- if (!arq)
- return 0;
-
- if (ad->last_sector[REQ_SYNC] < arq->request->sector)
- s = arq->request->sector - ad->last_sector[REQ_SYNC];
- else
- s = ad->last_sector[REQ_SYNC] - arq->request->sector;
+ if (aic->ttime_mean > ad->antic_expire) {
+ /* the process thinks too much between requests */
+ return 1;
+ }
- if (aic->seek_samples == 0) {
- /*
- * Process has just started IO. Use past statistics to
- * guage success possibility
- */
- if (ad->new_seek_mean/2 > s) {
- /* this request is better than what we're expecting */
- return 1;
- }
+ if (arq && aic->seek_samples) {
+ sector_t s;
+ if (ad->last_sector[REQ_SYNC] < arq->request->sector)
+ s = arq->request->sector - ad->last_sector[REQ_SYNC];
+ else
+ s = ad->last_sector[REQ_SYNC] - arq->request->sector;
- } else {
- if (aic->seek_mean/2 > s) {
+ if (aic->seek_mean > (s>>1)) {
/* this request is better than what we're expecting */
return 1;
}
@@ -802,51 +763,12 @@ static int as_can_anticipate(struct as_d
return 1;
}
-static void as_update_thinktime(struct as_data *ad, struct as_io_context *aic, unsigned long ttime)
-{
- /* fixed point: 1.0 == 1<<8 */
- if (aic->ttime_samples == 0) {
- ad->new_ttime_total = (7*ad->new_ttime_total + 256*ttime) / 8;
- ad->new_ttime_mean = ad->new_ttime_total / 256;
-
- ad->exit_prob = (7*ad->exit_prob)/8;
- }
- aic->ttime_samples = (7*aic->ttime_samples + 256) / 8;
- aic->ttime_total = (7*aic->ttime_total + 256*ttime) / 8;
- aic->ttime_mean = (aic->ttime_total + 128) / aic->ttime_samples;
-}
-
-static void as_update_seekdist(struct as_data *ad, struct as_io_context *aic, sector_t sdist)
-{
- u64 total;
-
- if (aic->seek_samples == 0) {
- ad->new_seek_total = (7*ad->new_seek_total + 256*(u64)sdist)/8;
- ad->new_seek_mean = ad->new_seek_total / 256;
- }
-
- /*
- * Don't allow the seek distance to get too large from the
- * odd fragment, pagein, etc
- */
- if (aic->seek_samples <= 60) /* second&third seek */
- sdist = min(sdist, (aic->seek_mean * 4) + 2*1024*1024);
- else
- sdist = min(sdist, (aic->seek_mean * 4) + 2*1024*64);
-
- aic->seek_samples = (7*aic->seek_samples + 256) / 8;
- aic->seek_total = (7*aic->seek_total + (u64)256*sdist) / 8;
- total = aic->seek_total + (aic->seek_samples/2);
- do_div(total, aic->seek_samples);
- aic->seek_mean = (sector_t)total;
-}
-
/*
* as_update_iohist keeps a decaying histogram of IO thinktimes, and
* updates @aic->ttime_mean based on that. It is called when a new
* request is queued.
*/
-static void as_update_iohist(struct as_data *ad, struct as_io_context *aic, struct request *rq)
+static void as_update_iohist(struct as_io_context *aic, struct request *rq)
{
struct as_rq *arq = RQ_DATA(rq);
int data_dir = arq->is_sync;
@@ -857,29 +779,60 @@ static void as_update_iohist(struct as_d
return;
if (data_dir == REQ_SYNC) {
- unsigned long in_flight = atomic_read(&aic->nr_queued)
- + atomic_read(&aic->nr_dispatched);
spin_lock(&aic->lock);
- if (test_bit(AS_TASK_IORUNNING, &aic->state) ||
- test_bit(AS_TASK_IOSTARTED, &aic->state)) {
+
+ if (test_bit(AS_TASK_IORUNNING, &aic->state)
+ && !atomic_read(&aic->nr_queued)
+ && !atomic_read(&aic->nr_dispatched)) {
/* Calculate read -> read thinktime */
- if (test_bit(AS_TASK_IORUNNING, &aic->state)
- && in_flight == 0) {
- thinktime = jiffies - aic->last_end_request;
- thinktime = min(thinktime, MAX_THINKTIME-1);
- } else
- thinktime = 0;
- as_update_thinktime(ad, aic, thinktime);
-
- /* Calculate read -> read seek distance */
- if (aic->last_request_pos < rq->sector)
- seek_dist = rq->sector - aic->last_request_pos;
- else
- seek_dist = aic->last_request_pos - rq->sector;
- as_update_seekdist(ad, aic, seek_dist);
- }
+ thinktime = jiffies - aic->last_end_request;
+ thinktime = min(thinktime, MAX_THINKTIME-1);
+ /* fixed point: 1.0 == 1<<8 */
+ aic->ttime_samples += 256;
+ aic->ttime_total += 256*thinktime;
+ if (aic->ttime_samples)
+ /* fixed point factor is cancelled here */
+ aic->ttime_mean = (aic->ttime_total + 128)
+ / aic->ttime_samples;
+ aic->ttime_samples = (aic->ttime_samples>>1)
+ + (aic->ttime_samples>>2);
+ aic->ttime_total = (aic->ttime_total>>1)
+ + (aic->ttime_total>>2);
+ }
+
+ /* Calculate read -> read seek distance */
+ if (!aic->seek_samples)
+ seek_dist = 0;
+ else if (aic->last_request_pos < rq->sector)
+ seek_dist = rq->sector - aic->last_request_pos;
+ else
+ seek_dist = aic->last_request_pos - rq->sector;
+
aic->last_request_pos = rq->sector + rq->nr_sectors;
- set_bit(AS_TASK_IOSTARTED, &aic->state);
+
+ /*
+ * Don't allow the seek distance to get too large from the
+ * odd fragment, pagein, etc
+ */
+ if (aic->seek_samples < 400) /* second&third seek */
+ seek_dist = min(seek_dist, (aic->seek_mean * 4)
+ + 2*1024*1024);
+ else
+ seek_dist = min(seek_dist, (aic->seek_mean * 4)
+ + 2*1024*64);
+
+ aic->seek_samples += 256;
+ aic->seek_total += (u64)256*seek_dist;
+ if (aic->seek_samples) {
+ u64 total = aic->seek_total + (aic->seek_samples>>1);
+ do_div(total, aic->seek_samples);
+ aic->seek_mean = (sector_t)total;
+ }
+ aic->seek_samples = (aic->seek_samples>>1)
+ + (aic->seek_samples>>2);
+ aic->seek_total = (aic->seek_total>>1)
+ + (aic->seek_total>>2);
+
spin_unlock(&aic->lock);
}
}
@@ -1426,8 +1379,8 @@ static void as_add_request(struct as_dat
arq->io_context = as_get_io_context();
if (arq->io_context) {
- as_update_iohist(ad, arq->io_context->aic, arq->request);
atomic_inc(&arq->io_context->aic->nr_queued);
+ as_update_iohist(arq->io_context->aic, arq->request);
}
alias = as_add_arq_rb(ad, arq);
@@ -1933,17 +1886,6 @@ as_var_store(unsigned long *var, const c
return count;
}
-static ssize_t as_est_show(struct as_data *ad, char *page)
-{
- int pos = 0;
-
- pos += sprintf(page+pos, "%lu %% exit probability\n", 100*ad->exit_prob/256);
- pos += sprintf(page+pos, "%lu ms new thinktime\n", ad->new_ttime_mean);
- pos += sprintf(page+pos, "%llu sectors new seek distance\n", (unsigned long long)ad->new_seek_mean);
-
- return pos;
-}
-
#define SHOW_FUNCTION(__FUNC, __VAR) \
static ssize_t __FUNC(struct as_data *ad, char *page) \
{ \
@@ -1975,10 +1917,6 @@ STORE_FUNCTION(as_write_batchexpire_stor
&ad->batch_expire[REQ_ASYNC], 0, INT_MAX);
#undef STORE_FUNCTION
-static struct as_fs_entry as_est_entry = {
- .attr = {.name = "est_time", .mode = S_IRUGO },
- .show = as_est_show,
-};
static struct as_fs_entry as_readexpire_entry = {
.attr = {.name = "read_expire", .mode = S_IRUGO | S_IWUSR },
.show = as_readexpire_show,
@@ -2006,7 +1944,6 @@ static struct as_fs_entry as_write_batch
};
static struct attribute *default_attrs[] = {
- &as_est_entry.attr,
&as_readexpire_entry.attr,
&as_writeexpire_entry.attr,
&as_anticexpire_entry.attr,
_
next prev parent reply other threads:[~2003-11-07 23:13 UTC|newest]
Thread overview: 132+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-11-03 18:22 2.9test9-mm1 and DAO ATAPI cd-burning corrupt Prakash K. Cheemplavam
2003-11-05 8:40 ` Jens Axboe
2003-11-05 9:55 ` Prakash K. Cheemplavam
2003-11-05 9:54 ` Jens Axboe
2003-11-05 10:01 ` Prakash K. Cheemplavam
2003-11-05 10:01 ` Jens Axboe
2003-11-05 10:12 ` Prakash K. Cheemplavam
2003-11-05 10:12 ` Jens Axboe
2003-11-05 10:20 ` Prakash K. Cheemplavam
2003-11-05 10:22 ` Jens Axboe
2003-11-05 10:31 ` Prakash K. Cheemplavam
2003-11-05 12:39 ` Jens Axboe
2003-11-05 18:47 ` Prakash K. Cheemplavam
2003-11-06 9:17 ` Jens Axboe
2003-11-06 12:42 ` Prakash K. Cheemplavam
2003-11-06 12:59 ` Nick Piggin
2003-11-06 13:00 ` Jens Axboe
2003-11-06 13:05 ` Nick Piggin
2003-11-06 13:05 ` Jens Axboe
2003-11-06 13:11 ` Nick Piggin
2003-11-06 13:11 ` Jens Axboe
2003-11-06 13:31 ` Prakash K. Cheemplavam
2003-11-06 13:31 ` Jens Axboe
2003-11-06 13:44 ` Prakash K. Cheemplavam
2003-11-06 13:47 ` Jens Axboe
2003-11-06 13:54 ` Nick Piggin
2003-11-06 13:52 ` Jens Axboe
2003-11-10 21:45 ` bill davidsen
2003-11-06 14:00 ` Prakash K. Cheemplavam
2003-11-06 13:58 ` Prakash K. Cheemplavam
2003-11-06 13:51 ` Jens Axboe
2003-11-06 14:31 ` Prakash K. Cheemplavam
2003-11-06 17:42 ` Matthew Reppert
2003-11-06 18:48 ` Prakash K. Cheemplavam
2003-11-06 19:45 ` Maciej Zenczykowski
2003-11-06 14:38 ` Prakash K. Cheemplavam
2003-11-06 18:49 ` Martin Josefsson
2003-11-06 19:06 ` Prakash K. Cheemplavam
2003-11-06 20:07 ` Martin Josefsson
[not found] ` <3FAB0754.2040209@cyberone.com.au>
2003-11-07 11:18 ` Prakash K. Cheemplavam
2003-11-07 11:31 ` Nick Piggin
[not found] ` <3FAB8428.7090307@gmx.de>
[not found] ` <3FAB870D.1050003@cyberone.com.au>
2003-11-07 12:53 ` Prakash K. Cheemplavam
2003-11-07 13:03 ` Nick Piggin [this message]
[not found] ` <3FAB9C2B.2040907@gmx.de>
[not found] ` <3FAB9F97.6050706@cyberone.com.au>
[not found] ` <3FABA364.9000404@gmx.de>
[not found] ` <3FABA5A7.904@cyberone.com.au>
[not found] ` <3FABA6EF.90207@gmx.de>
[not found] ` <3FABA788.1080000@cyberone.com.au>
[not found] ` <3FABAB5B.5090105@gmx.de>
[not found] ` <3FABAE0B.6020601@cyberone.com.au>
[not found] ` <3FABB08B.3080006@gmx.de>
[not found] ` <3FABB571.6070804@cyberone.com.au>
2003-11-07 15:48 ` Prakash K. Cheemplavam
2003-11-08 2:14 ` Nick Piggin
2003-11-08 12:31 ` Prakash K. Cheemplavam
2003-11-08 21:17 ` Randy.Dunlap
2003-11-10 22:23 ` bill davidsen
2003-11-11 14:46 ` Zwane Mwaikambo
2003-11-11 15:31 ` bill davidsen
2003-11-10 22:26 ` bill davidsen
2003-11-10 21:25 ` bill davidsen
2003-11-06 19:14 ` bill davidsen
2003-11-06 19:45 ` Linus Torvalds
2003-11-07 9:13 ` Rob Landley
2003-11-07 14:21 ` Bill Davidsen
2003-11-07 23:25 ` Rob Landley
2003-11-08 2:39 ` Nick Piggin
2003-11-07 12:46 ` Jens Axboe
2003-11-06 19:55 ` Gene Heskett
2003-11-06 22:36 ` Bill Davidsen
2003-11-07 0:51 ` Gene Heskett
2003-11-10 22:14 ` bill davidsen
2003-11-05 10:26 ` Nick Piggin
2003-11-05 10:29 ` Jens Axboe
2003-11-05 10:36 ` Prakash K. Cheemplavam
2003-11-05 11:14 ` Nick Piggin
2003-11-05 12:38 ` Jens Axboe
2003-11-05 17:36 ` Prakash K. Cheemplavam
2003-11-05 18:43 ` Prakash K. Cheemplavam
2003-11-05 10:54 ` Gene Heskett
2003-11-05 11:26 ` Jens Axboe
2003-11-05 10:33 ` Prakash K. Cheemplavam
2003-11-06 19:08 ` bill davidsen
2003-11-06 19:35 ` Linus Torvalds
2003-11-06 19:56 ` John Bradford
2003-11-07 14:10 ` Bill Davidsen
2003-11-07 15:01 ` Linus Torvalds
2003-11-08 15:06 ` Ragnar Hojland Espinosa
2003-11-08 17:52 ` Linus Torvalds
2003-11-08 18:16 ` viro
2003-11-10 19:22 ` Bill Davidsen
2003-11-10 19:01 ` Bill Davidsen
2003-11-10 19:25 ` Linus Torvalds
2003-11-10 20:03 ` Bill Davidsen
2003-11-10 20:22 ` Linus Torvalds
2003-11-11 4:48 ` bill davidsen
2003-11-11 5:40 ` Linus Torvalds
2003-11-11 17:49 ` Diego Calleja García
2003-11-11 18:15 ` Diego Calleja García
2003-11-12 22:58 ` bill davidsen
2003-11-12 23:47 ` Bartlomiej Zolnierkiewicz
2003-11-13 7:06 ` Jens Axboe
2003-11-15 13:13 ` Bill Davidsen
2003-11-15 13:43 ` Jens Axboe
2003-11-17 13:23 ` Bill Davidsen
2003-11-06 21:10 ` Prakash K. Cheemplavam
2003-11-06 21:40 ` Prakash K. Cheemplavam
2003-11-07 21:05 ` Jens Axboe
2003-11-09 10:49 ` Prakash K. Cheemplavam
2003-11-10 22:06 ` bill davidsen
2003-11-07 9:46 ` Xavier Bestel
2003-11-07 8:24 ` Jens Axboe
2003-11-05 11:17 ` DervishD
[not found] ` <3FA8C8E5.10903@gmx.de>
[not found] ` <20031105095350.GF1477@suse.de>
2003-11-05 10:00 ` Prakash K. Cheemplavam
[not found] <OXZz.7Uj.3@gated-at.bofh.it>
[not found] ` <OY9D.86A.29@gated-at.bofh.it>
2003-11-06 21:22 ` Pascal Schmidt
[not found] <QyWV.2Zi.1@gated-at.bofh.it>
[not found] ` <QzzF.3WK.3@gated-at.bofh.it>
2003-11-11 16:43 ` Pascal Schmidt
2003-11-11 17:00 ` Linus Torvalds
[not found] <Pine.LNX.4.44.0311110950250.30657-100000@home.osdl.org>
2003-11-11 19:41 ` Pascal Schmidt
2003-11-11 22:50 ` Martin Schlemmer
2003-11-11 21:41 ` Pascal Schmidt
2003-11-11 22:04 ` Linus Torvalds
2003-11-11 23:46 ` Pascal Schmidt
2003-11-12 1:14 ` Linus Torvalds
2003-11-12 17:32 ` Pascal Schmidt
2003-11-12 18:20 ` Pascal Schmidt
2003-11-12 18:31 ` Jens Axboe
2003-11-12 19:44 ` Pascal Schmidt
2003-11-13 11:52 ` Bill Davidsen
2003-11-13 12:20 ` Jens Axboe
2003-11-13 13:19 ` Pascal Schmidt
2003-11-13 14:35 ` Jens Axboe
2003-11-13 15:22 ` Linus Torvalds
2003-11-13 15:27 ` Jens Axboe
2003-11-15 13:16 ` Bill Davidsen
2003-11-13 13:17 ` Pascal Schmidt
2003-11-15 13:04 ` Bill Davidsen
2003-11-12 0:04 ` Daniel Pittman
2003-11-12 0:09 ` Pascal Schmidt
[not found] <RoMa.Mi.7@gated-at.bofh.it>
[not found] ` <RpI1.2RG.5@gated-at.bofh.it>
[not found] ` <RqNS.54j.11@gated-at.bofh.it>
2003-11-13 15:05 ` Pascal Schmidt
2003-11-13 15:28 ` Jens Axboe
2003-11-13 15:32 ` Pascal Schmidt
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