Re: [PATCH #upstream-fixes] sata_mv: don't issue two DMA commands concurrently

[Bokhan Artem <APTEM@ngs.ru>]

As it named RETRY, I set it to 0, "define SD_MAX_RETRIES        0"
But still got two retries. Any suggestions?

dd if=/dev/sda of=/dev/null bs=512 skip=20359137 count=1

Aug 13 15:50:02 ubuntu kernel: [  244.688030]          res 
51/40:08:e0:a7:36/01:00:01:00:00/00 Emask 0x409 (media error) <F>
Aug 13 15:50:02 ubuntu kernel: [  244.688206] ata5: hard resetting link
Aug 13 15:50:02 ubuntu kernel: [  245.226248] ata5: SATA link up 3.0 
Gbps (SStatus 123 SControl 300)
Aug 13 15:50:02 ubuntu kernel: [  245.306267] ata5.00: max_sectors 
limited to 256 for NCQ
Aug 13 15:50:02 ubuntu kernel: [  245.388635] ata5.00: max_sectors 
limited to 256 for NCQ
Aug 13 15:50:02 ubuntu kernel: [  245.388637] ata5.00: configured for 
UDMA/133
Aug 13 15:50:02 ubuntu kernel: [  245.388643] sd 4:0:0:0: [sda] Result: 
hostbyte=DID_OK driverbyte=DRIVER_SENSE,SUGGEST_OK
Aug 13 15:50:02 ubuntu kernel: [  245.388646] sd 4:0:0:0: [sda] Sense 
Key : Medium Error [current] [descriptor]
Aug 13 15:50:02 ubuntu kernel: [  245.388649] Descriptor sense data with 
sense descriptors (in hex):
Aug 13 15:50:02 ubuntu kernel: [  245.388651]         72 03 11 04 00 00 
00 0c 00 0a 80 00 00 00 00 00
Aug 13 15:50:02 ubuntu kernel: [  245.388658]         01 36 a7 e0
Aug 13 15:50:02 ubuntu kernel: [  245.388661] sd 4:0:0:0: [sda] Add. 
Sense: Unrecovered read error - auto reallocate failed
Aug 13 15:50:02 ubuntu kernel: [  245.388783] ata5: EH complete
Aug 13 15:50:02 ubuntu kernel: [  245.388722] sd 4:0:0:0: [sda] 
1465149168 512-byte hardware sectors (750156 MB)
Aug 13 15:50:02 ubuntu kernel: [  245.388722] sd 4:0:0:0: [sda] Write 
Protect is off
Aug 13 15:50:02 ubuntu kernel: [  245.388722] sd 4:0:0:0: [sda] Write 
cache: enabled, read cache: enabled, doesn't support DPO or FUA

Aug 13 15:50:04 ubuntu kernel: [  247.117648]          res 
51/40:08:e0:a7:36/01:00:01:00:00/00 Emask 0x409 (media error) <F>
Aug 13 15:50:04 ubuntu kernel: [  247.117824] ata5: hard resetting link
Aug 13 15:50:04 ubuntu kernel: [  247.659679] ata5: SATA link up 3.0 
Gbps (SStatus 123 SControl 300)
Aug 13 15:50:04 ubuntu kernel: [  247.747372] ata5.00: max_sectors 
limited to 256 for NCQ
Aug 13 15:50:04 ubuntu kernel: [  247.825139] ata5.00: max_sectors 
limited to 256 for NCQ
Aug 13 15:50:04 ubuntu kernel: [  247.825141] ata5.00: configured for 
UDMA/133
Aug 13 15:50:04 ubuntu kernel: [  247.825145] sd 4:0:0:0: [sda] Result: 
hostbyte=DID_OK driverbyte=DRIVER_SENSE,SUGGEST_OK
Aug 13 15:50:04 ubuntu kernel: [  247.825148] sd 4:0:0:0: [sda] Sense 
Key : Medium Error [current] [descriptor]
Aug 13 15:50:04 ubuntu kernel: [  247.825151] Descriptor sense data with 
sense descriptors (in hex):
Aug 13 15:50:04 ubuntu kernel: [  247.825153]         72 03 11 04 00 00 
00 0c 00 0a 80 00 00 00 00 00
Aug 13 15:50:04 ubuntu kernel: [  247.825160]         01 36 a7 e0
Aug 13 15:50:04 ubuntu kernel: [  247.825163] sd 4:0:0:0: [sda] Add. 
Sense: Unrecovered read error - auto reallocate failed
Aug 13 15:50:04 ubuntu kernel: [  247.825281] ata5: EH complete
Aug 13 15:50:04 ubuntu kernel: [  247.825223] sd 4:0:0:0: [sda] 
1465149168 512-byte hardware sectors (750156 MB)
Aug 13 15:50:04 ubuntu kernel: [  247.825223] sd 4:0:0:0: [sda] Write 
Protect is off
Aug 13 15:50:04 ubuntu kernel: [  247.825223] sd 4:0:0:0: [sda] Write 
cache: enabled, read cache: enabled, doesn't support DPO or FUA



Mark Lord пишет:
> Artem Bokhan wrote:
>> When I run 'dd if=/dev/sda of=/dev/null skip=9700 bs=1M' and it meets 
>> bad block, it takes about 
>> '/sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/0000:02:02.0/host4/target4:0:0/4:0:0:0/timeout 
>> + about 10 seconds' to determine I/O error. Until that IO to device 
>> is locked, as I understand. I want to reduce the time of lock as  
>> much as possible.
> ..
>
> Tell the SCSI layer to stop flogging the drive with unnecessary retries.
> A quick and dirty way, is this patch below, but it really should be more
> intelligent than this for some situations:
>
> --- linux/include/scsi/sd.h.orig    2008-06-09 14:27:19.000000000 -0400
> +++ linux/include/scsi/sd.h    2008-08-13 12:16:01.000000000 -0400
> @@ -23,7 +23,7 @@
> /*
>  * Number of allowed retries
>  */
> -#define SD_MAX_RETRIES        5
> +#define SD_MAX_RETRIES        1
> #define SD_PASSTHROUGH_RETRIES    1
>
> /*