Question about handle_failed_sync()

Question about handle_failed_sync()

[majianpeng]

 In function handle_failed_sync():
>>/* During recovery devices cannot be removed, so locking and
>>	 * refcounting of rdevs is not needed
>>	 */
>>	for (i = 0; i < conf->raid_disks; i++) {
>>		struct md_rdev *rdev = conf->disks[i].rdev;
>>		if (rdev
>>		    && !test_bit(Faulty, &rdev->flags)
>>		    && !test_bit(In_sync, &rdev->flags)
>>		    && !rdev_set_badblocks(rdev, sh->sector,
>>					   STRIPE_SECTORS, 0))
>>			abort = 1;

I have two questions:
1:if raid have two or more spare disks, it wil set bad block on all spare disk. Is it worth it?
2:If raid have two or more spare disks,I can remove spare disks which not working for recovery.Then you shold add locking 
   and refconting.
 				
--------------
majianpeng
2012-03-14

Re: Question about handle_failed_sync()

[NeilBrown]

[-- Attachment #1: Type: text/plain, Size: 1601 bytes --]

On Wed, 14 Mar 2012 15:16:45 +0800 "majianpeng" <majianpeng@gmail.com> wrote:

>  In function handle_failed_sync():
> >>/* During recovery devices cannot be removed, so locking and
> >>	 * refcounting of rdevs is not needed
> >>	 */
> >>	for (i = 0; i < conf->raid_disks; i++) {
> >>		struct md_rdev *rdev = conf->disks[i].rdev;
> >>		if (rdev
> >>		    && !test_bit(Faulty, &rdev->flags)
> >>		    && !test_bit(In_sync, &rdev->flags)
> >>		    && !rdev_set_badblocks(rdev, sh->sector,
> >>					   STRIPE_SECTORS, 0))
> >>			abort = 1;
> 
> I have two questions:
> 1:if raid have two or more spare disks, it wil set bad block on all spare disk. Is it worth it?

This is not looking at spare disks exactly.  Rather it is looking at
devices that are being recovered - they were spares by now they are member of
the array that are being recovered.
So there will only be 2 in RAID6 and never more.

And yes, it is worth it.


> 2:If raid have two or more spare disks,I can remove spare disks which not working for recovery.Then you shold add locking 
>    and refconting.

I'm not iterating through the list of disks (mddev->disks) here - just
through the list of devices that are active members of the array
(conf->disks).
You cannot remove those while recovery is happening.

Thanks,
NeilBrown



>  				
> --------------
> majianpeng
> 2012-03-14
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-raid" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html


[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 828 bytes --]