PATCH for ide_floppy

From: Manfred.Scherer.Mhm@xxxxxxxxxxx
Date: Fri Jul 01 2005 - 10:32:43 EST

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Hi Paul

The runtime for copy of two 50MB files to a IOMEGA-100-Zip-IDE-device
seems to be not
deterministic since Linux Kernel 2.6.x.

A lot of runtime will be spent to waiting for IO. 'top -i' will show
this:

top - 03:54:23 up 37 min, 9 users, load average: 1.28, 1.52, 0.99
Tasks: 90 total, 1 running, 89 sleeping, 0 stopped, 0 zombie
Cpu(s): 3.6% us, 1.0% sy, 0.0% ni, 0.0% id, 95.0% wa, 0.3% hi,
0.0% si
Mem: 190836k total, 189416k used, 1420k free, 10796k buffers
Swap: 529912k total, 4288k used, 525624k free, 99364k cached

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
5649 root 17 0 1968 944 1764 R 0.3 0.5 0:01.47 top
5672 root 24 0 1648 524 1492 D 0.0 0.3 0:00.18 umount

... umount is pending with "95.0% wa"

The tests will be done with a small shell script cpzip.sh similar to
this:

mount /dev/hdd4 /dzip
rm /dzip/*.cgz
cp -p $* /dzip
umount /dzip
eject /dzip

__________________________________
files:
-rw-r--r-- 1 root root 50167808 Jun 19 19:17 0_LW_1_ux.cgz
-rw-r--r-- 1 root root 50167808 Jun 19 19:18 0_LW_2_ux.cgz

measured runtimes:

pc1:/scm/save_a/wcb # time ./cpzip.sh 0_LW_1_ux.cgz 0_LW_2_ux.cgz
real 9m18.486s
user 0m0.042s
sys 0m2.450s
pc1:/scm/save_a/wcb #

pc1:/scm/save_a/wcb # time ./cpzip.sh 0_LW_1_ux.cgz 0_LW_2_ux.cgz
real 4m24.953s
user 0m0.036s
sys 0m2.584s
pc1:/scm/save_a/wcb #

pc1:/scm/save_a/wcb # time ./cpzip.sh 0_LW_1_ux.cgz 0_LW_2_ux.cgz
real 22m50.351s
user 0m0.047s
sys 0m2.789s
pc1:/scm/save_a/wcb #

pc1:/scm/save_a/wcb # time ./cpzip.sh 0_LW_1_ux.cgz 0_LW_2_ux.cgz
real 17m44.786s
user 0m0.048s
sys 0m2.758s
pc1:/scm/save_a/wcb #

pc1:/scm/save_a/wcb # time ./cpzip.sh 0_LW_1_ux.cgz 0_LW_2_ux.cgz
real 5m11.958s
user 0m0.051s
sys 0m2.558s
pc1:/scm/save_a/wcb #

pc1:/scm/save_a/wcb # time ./cpzip.sh 0_LW_1_ux.cgz 0_LW_2_ux.cgz
real 19m37.694s
user 0m0.043s
sys 0m2.821s
pc1:/scm/save_a/wcb #

pc1:/scm/save_a/wcb # time ./cpzip.sh 0_LW_1_ux.cgz 0_LW_2_ux.cgz
real 32m9.964s
user 0m0.047s
sys 0m2.766s
pc1:/scm/save_a/wcb #

pc1:/scm/save_a/wcb # time ./cpzip.sh 0_LW_1_ux.cgz 0_LW_2_ux.cgz
real 6m26.194s
user 0m0.041s
sys 0m2.517s
pc1:/scm/save_a/wcb #

______________________
runtimes after applying my patch:

pc1:/scm/save_a/wcb # time ./cpzip.sh 0_LW_1_ux.cgz 0_LW_2_ux.cgz
real 6m15.780s
user 0m0.057s
sys 0m2.212s
pc1:/scm/save_a/wcb #

pc1:/scm/save_a/wcb # time ./cpzip.sh 0_LW_1_ux.cgz 0_LW_2_ux.cgz
real 5m54.664s
user 0m0.035s
sys 0m2.287s
pc1:/scm/save_a/wcb #

pc1:/scm/save_a/wcb # time ./cpzip.sh 0_LW_1_ux.cgz 0_LW_2_ux.cgz
real 5m55.325s
user 0m0.041s
sys 0m2.330s
pc1:/scm/save_a/wcb #

pc1:/scm/save_a/wcb # time ./cpzip.sh 0_LW_1_ux.cgz 0_LW_2_ux.cgz
real 6m9.513s
user 0m0.040s
sys 0m2.352s
pc1:/scm/save_a/wcb #

pc1:/scm/save_a/wcb # time ./cpzip.sh 0_LW_1_ux.cgz 0_LW_2_ux.cgz
real 6m24.069s
user 0m0.052s
sys 0m2.322s
pc1:/scm/save_a/wcb #

_________________________________________________________________

Patch:

--- linux-2.6.12/drivers/ide/ide.c.ORIG 2005-06-17 21:48:29.000000000
+0200
+++ linux-2.6.12/drivers/ide/ide.c 2005-06-25 03:55:28.000000000
+0200
@@ -240,6 +240,7 @@
drive->name[0] = 'h';
drive->name[1] = 'd';
drive->name[2] = 'a' + (index *
MAX_DRIVES) + unit;
+ drive->failures = 0; /* --ms
2004/12/29 */
drive->max_failures =
IDE_DEFAULT_MAX_FAILURES;
drive->using_dma = 0;
drive->is_flash = 0;

--- linux-2.6.12/drivers/ide/ide-floppy.c.ORIG 2005-06-17
21:48:29.000000000 +0200
+++ linux-2.6.12/drivers/ide/ide-floppy.c 2005-06-25
03:29:45.000000000 +0200
@@ -125,7 +125,14 @@
/*
* Some drives require a longer irq timeout.
*/
+#if 0
#define IDEFLOPPY_WAIT_CMD (5 * WAIT_CMD)
+#endif
+#if 0
+#define IDEFLOPPY_WAIT_CMD 200 /* --ms */
+#endif
+#define IDEFLOPPY_WAIT_CMD WAIT_CMD /* 2004/12/31
--ms */
+

/*
* After each failed packet command we issue a request sense
command
@@ -317,7 +324,13 @@
unsigned long flags;
} idefloppy_floppy_t;

+#if 0
#define IDEFLOPPY_TICKS_DELAY 3 /* default delay for ZIP 100 */
+#define IDEFLOPPY_TICKS_DELAY 6 /* default delay for ZIP 100
--ms 2005/01/01 */
+#define IDEFLOPPY_TICKS_DELAY 12 /* default delay for ZIP 100
--ms 2005/01/01 */
+#endif
+#define IDEFLOPPY_TICKS_DELAY 60 /* default delay for ZIP 100
--ms 2005/01/07 */
+

/*
* Floppy flag bits values.
@@ -774,6 +787,35 @@
pc->callback = &idefloppy_pc_callback;
}

+/*
+ * Similar to ide-cd.c 2004/12/31 --ms
+ */
+static int idefloppy_timer_expiry(ide_drive_t *drive)
+{
+ struct request *rq = HWGROUP(drive)->rq;
+ unsigned long wait = 0;
+
+ /*
+ * Some commands are *slow* and normally take a long time to
+ * complete. Usually we can use the ATAPI "disconnect" to bypass
+ * this, but not all commands/drives support that. Let
+ * ide_timer_expiry keep polling us for these.
+ */
+ switch (rq->cmd[0]) {
+ case GPCMD_BLANK:
+ case GPCMD_FORMAT_UNIT:
+ case GPCMD_FLUSH_CACHE:
+ wait = IDEFLOPPY_WAIT_CMD;
+ break;
+ default:
+ if (!(rq->flags & REQ_QUIET))
+ printk(KERN_INFO "ide-floppy: cmd 0x%x
timed out\n", rq->cmd[0]);
+ wait = 0;
+ break;
+ }
+ return wait;
+}
+
static void idefloppy_create_request_sense_cmd (idefloppy_pc_t *pc)
{
idefloppy_init_pc(pc);
@@ -900,7 +942,7 @@
ide_set_handler(drive,
&idefloppy_pc_intr,
IDEFLOPPY_WAIT_CMD,
- NULL);
+ idefloppy_timer_expiry
/* NULL --ms */);
return ide_started;
}
debug_log(KERN_NOTICE "ide-floppy: The floppy
wants to "
@@ -931,7 +973,10 @@

if (HWGROUP(drive)->handler != NULL)
BUG();
- ide_set_handler(drive, &idefloppy_pc_intr, IDEFLOPPY_WAIT_CMD,
NULL); /* And set the interrupt handler again */
+ /* And set the interrupt handler again */
+ ide_set_handler(drive, &idefloppy_pc_intr,
+ IDEFLOPPY_WAIT_CMD,
+ idefloppy_timer_expiry /* NULL --ms */);
return ide_started;
}

@@ -960,7 +1005,9 @@
if (HWGROUP(drive)->handler != NULL)
BUG();
/* Set the interrupt routine */
- ide_set_handler(drive, &idefloppy_pc_intr, IDEFLOPPY_WAIT_CMD,
NULL);
+ ide_set_handler(drive, &idefloppy_pc_intr,
+ IDEFLOPPY_WAIT_CMD,
+ idefloppy_timer_expiry /* NULL --ms */);
/* Send the actual packet */
HWIF(drive)->atapi_output_bytes(drive, floppy->pc->c, 12);
return ide_started;
@@ -1116,6 +1163,7 @@
}

/* Can we transfer the packet when we get the interrupt or wait?
*/
+/* 2005/01/01 --ms, this is really necessary! */
if (test_bit(IDEFLOPPY_ZIP_DRIVE, &floppy->flags)) {
/* wait */
pkt_xfer_routine = &idefloppy_transfer_pc1;
@@ -1129,7 +1177,7 @@
ide_execute_command(drive, WIN_PACKETCMD,
pkt_xfer_routine,
IDEFLOPPY_WAIT_CMD,
- NULL);
+ idefloppy_timer_expiry /* NULL --ms */);
return ide_started;
} else {
/* Issue the packet command */

Signed-off-by: Manfred Scherer <manfred.scherer.mhm@xxxxxxxxxxx>
___________________________________________________________________
My system is:

pc1:~ # uname -a
Linux pc1 2.6.12 #2 Sat Jun 25 04:02:24 CEST 2005 i686 athlon i386
GNU/Linux
pc1:~ #

pc1:~ # grep -i iomega /var/log/boot.msg
<4>hdd: IOMEGA ZIP 100 ATAPI, ATAPI FLOPPY drive

pc1:~ # cat /proc/cpuinfo
processor : 0
vendor_id : AuthenticAMD
cpu family : 6
model : 4
model name : AMD Athlon(tm) processor
stepping : 2
cpu MHz : 1000.250

EOF

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Next message: Artem B. Bityuckiy: "Re: reiser4 vs politics: linux misses out again"
Previous message: arjun kumar: "reiser4 vs politics: linux misses out again"
Next in thread: Jens Axboe: "Re: PATCH for ide_floppy"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]