diff options
| author | NeilBrown | 2005-11-08 21:39:31 -0800 |
|---|---|---|
| committer | Linus Torvalds | 2005-11-09 07:56:38 -0800 |
| commit | ba22dcbf106338a5c46d6979f9b19564faae3d49 (patch) | |
| tree | 4caae4532cda0412d2446eca8b036d4e0df447f8 | |
| parent | 007583c9253fed363a0bd71b039e9b40a0f6855e (diff) | |
[PATCH] md: improvements to raid5 handling of read errors
Two refinements to the 'attempt-overwrite-on-read-error' mechanism.
1/ If the array is read-only, don't attempt an over-write.
2/ If there are more than max_nr_stripes read errors on a device with
no success, fail the drive. This will make sure a dead
drive will be eventually kicked even when we aren't trying
to rewrite (which would normally kick a dead drive more quickly.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
| -rw-r--r-- | drivers/md/md.c | 1 | ||||
| -rw-r--r-- | drivers/md/raid5.c | 25 | ||||
| -rw-r--r-- | include/linux/raid/md_k.h | 3 |
3 files changed, 21 insertions, 8 deletions
diff --git a/drivers/md/md.c b/drivers/md/md.c index 3db5c3513072..3fb80397f8aa 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -1582,6 +1582,7 @@ static mdk_rdev_t *md_import_device(dev_t newdev, int super_format, int super_mi rdev->in_sync = 0; rdev->data_offset = 0; atomic_set(&rdev->nr_pending, 0); + atomic_set(&rdev->read_errors, 0); size = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS; if (!size) { diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 08a1620b9f8c..77610b98d4e0 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -420,21 +420,29 @@ static int raid5_end_read_request(struct bio * bi, unsigned int bytes_done, clear_bit(R5_ReadError, &sh->dev[i].flags); clear_bit(R5_ReWrite, &sh->dev[i].flags); } + if (atomic_read(&conf->disks[i].rdev->read_errors)) + atomic_set(&conf->disks[i].rdev->read_errors, 0); } else { + int retry = 0; clear_bit(R5_UPTODATE, &sh->dev[i].flags); - if (conf->mddev->degraded) { + atomic_inc(&conf->disks[i].rdev->read_errors); + if (conf->mddev->degraded) printk("R5: read error not correctable.\n"); - clear_bit(R5_ReadError, &sh->dev[i].flags); - clear_bit(R5_ReWrite, &sh->dev[i].flags); - md_error(conf->mddev, conf->disks[i].rdev); - } else if (test_bit(R5_ReWrite, &sh->dev[i].flags)) { + else if (test_bit(R5_ReWrite, &sh->dev[i].flags)) /* Oh, no!!! */ printk("R5: read error NOT corrected!!\n"); + else if (atomic_read(&conf->disks[i].rdev->read_errors) + > conf->max_nr_stripes) + printk("raid5: Too many read errors, failing device.\n"); + else + retry = 1; + if (retry) + set_bit(R5_ReadError, &sh->dev[i].flags); + else { clear_bit(R5_ReadError, &sh->dev[i].flags); clear_bit(R5_ReWrite, &sh->dev[i].flags); md_error(conf->mddev, conf->disks[i].rdev); - } else - set_bit(R5_ReadError, &sh->dev[i].flags); + } } rdev_dec_pending(conf->disks[i].rdev, conf->mddev); #if 0 @@ -1328,7 +1336,8 @@ static void handle_stripe(struct stripe_head *sh) /* If the failed drive is just a ReadError, then we might need to progress * the repair/check process */ - if (failed == 1 && test_bit(R5_ReadError, &sh->dev[failed_num].flags) + if (failed == 1 && ! conf->mddev->ro && + test_bit(R5_ReadError, &sh->dev[failed_num].flags) && !test_bit(R5_LOCKED, &sh->dev[failed_num].flags) && test_bit(R5_UPTODATE, &sh->dev[failed_num].flags) ) { diff --git a/include/linux/raid/md_k.h b/include/linux/raid/md_k.h index 4169c11e5451..200c69e34fc0 100644 --- a/include/linux/raid/md_k.h +++ b/include/linux/raid/md_k.h @@ -134,6 +134,9 @@ struct mdk_rdev_s * only maintained for arrays that * support hot removal */ + atomic_t read_errors; /* number of consecutive read errors that + * we have tried to ignore. + */ }; typedef struct mdk_personality_s mdk_personality_t; |