diff --git a/drivers/md/md.c b/drivers/md/md.c index 859edbf8c9b0a72679f86ff035c23e5e2949cb6c..f1b905a201335e3540af357da2eb554acca8eea6 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -67,6 +67,12 @@ static DECLARE_WAIT_QUEUE_HEAD(resync_wait); #define MD_BUG(x...) { printk("md: bug in file %s, line %d\n", __FILE__, __LINE__); md_print_devices(); } +/* + * Default number of read corrections we'll attempt on an rdev + * before ejecting it from the array. We divide the read error + * count by 2 for every hour elapsed between read errors. + */ +#define MD_DEFAULT_MAX_CORRECTED_READ_ERRORS 20 /* * Current RAID-1,4,5 parallel reconstruction 'guaranteed speed limit' * is 1000 KB/sec, so the extra system load does not show up that much. @@ -2653,6 +2659,8 @@ static mdk_rdev_t *md_import_device(dev_t newdev, int super_format, int super_mi rdev->flags = 0; rdev->data_offset = 0; rdev->sb_events = 0; + rdev->last_read_error.tv_sec = 0; + rdev->last_read_error.tv_nsec = 0; atomic_set(&rdev->nr_pending, 0); atomic_set(&rdev->read_errors, 0); atomic_set(&rdev->corrected_errors, 0); @@ -3289,6 +3297,29 @@ array_state_store(mddev_t *mddev, const char *buf, size_t len) static struct md_sysfs_entry md_array_state = __ATTR(array_state, S_IRUGO|S_IWUSR, array_state_show, array_state_store); +static ssize_t +max_corrected_read_errors_show(mddev_t *mddev, char *page) { + return sprintf(page, "%d\n", + atomic_read(&mddev->max_corr_read_errors)); +} + +static ssize_t +max_corrected_read_errors_store(mddev_t *mddev, const char *buf, size_t len) +{ + char *e; + unsigned long n = simple_strtoul(buf, &e, 10); + + if (*buf && (*e == 0 || *e == '\n')) { + atomic_set(&mddev->max_corr_read_errors, n); + return len; + } + return -EINVAL; +} + +static struct md_sysfs_entry max_corr_read_errors = +__ATTR(max_read_errors, S_IRUGO|S_IWUSR, max_corrected_read_errors_show, + max_corrected_read_errors_store); + static ssize_t null_show(mddev_t *mddev, char *page) { @@ -3914,6 +3945,7 @@ static struct attribute *md_default_attrs[] = { &md_array_state.attr, &md_reshape_position.attr, &md_array_size.attr, + &max_corr_read_errors.attr, NULL, }; @@ -4333,6 +4365,8 @@ static int do_md_run(mddev_t * mddev) mddev->ro = 0; atomic_set(&mddev->writes_pending,0); + atomic_set(&mddev->max_corr_read_errors, + MD_DEFAULT_MAX_CORRECTED_READ_ERRORS); mddev->safemode = 0; mddev->safemode_timer.function = md_safemode_timeout; mddev->safemode_timer.data = (unsigned long) mddev; diff --git a/drivers/md/md.h b/drivers/md/md.h index d9138885b87f420b42babc247c54a4ddc6815269..8e4c75c00d4628f76ca32e0aaab243e3aea70d4c 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -97,6 +97,9 @@ struct mdk_rdev_s atomic_t read_errors; /* number of consecutive read errors that * we have tried to ignore. */ + struct timespec last_read_error; /* monotonic time since our + * last read error + */ atomic_t corrected_errors; /* number of corrected read errors, * for reporting to userspace and storing * in superblock. @@ -299,6 +302,7 @@ struct mddev_s int external; } bitmap_info; + atomic_t max_corr_read_errors; /* max read retries */ struct list_head all_mddevs; /* Generic barrier handling. diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 670449f7411fcef371aee08ddab50e608a826ae7..5c71a462c1203356dceae8ecec36e7309877365a 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -1431,6 +1431,43 @@ static void recovery_request_write(mddev_t *mddev, r10bio_t *r10_bio) } +/* + * Used by fix_read_error() to decay the per rdev read_errors. + * We halve the read error count for every hour that has elapsed + * since the last recorded read error. + * + */ +static void check_decay_read_errors(mddev_t *mddev, mdk_rdev_t *rdev) +{ + struct timespec cur_time_mon; + unsigned long hours_since_last; + unsigned int read_errors = atomic_read(&rdev->read_errors); + + ktime_get_ts(&cur_time_mon); + + if (rdev->last_read_error.tv_sec == 0 && + rdev->last_read_error.tv_nsec == 0) { + /* first time we've seen a read error */ + rdev->last_read_error = cur_time_mon; + return; + } + + hours_since_last = (cur_time_mon.tv_sec - + rdev->last_read_error.tv_sec) / 3600; + + rdev->last_read_error = cur_time_mon; + + /* + * if hours_since_last is > the number of bits in read_errors + * just set read errors to 0. We do this to avoid + * overflowing the shift of read_errors by hours_since_last. + */ + if (hours_since_last >= 8 * sizeof(read_errors)) + atomic_set(&rdev->read_errors, 0); + else + atomic_set(&rdev->read_errors, read_errors >> hours_since_last); +} + /* * This is a kernel thread which: * @@ -1444,6 +1481,43 @@ static void fix_read_error(conf_t *conf, mddev_t *mddev, r10bio_t *r10_bio) int sect = 0; /* Offset from r10_bio->sector */ int sectors = r10_bio->sectors; mdk_rdev_t*rdev; + int max_read_errors = atomic_read(&mddev->max_corr_read_errors); + + rcu_read_lock(); + { + int d = r10_bio->devs[r10_bio->read_slot].devnum; + char b[BDEVNAME_SIZE]; + int cur_read_error_count = 0; + + rdev = rcu_dereference(conf->mirrors[d].rdev); + bdevname(rdev->bdev, b); + + if (test_bit(Faulty, &rdev->flags)) { + rcu_read_unlock(); + /* drive has already been failed, just ignore any + more fix_read_error() attempts */ + return; + } + + check_decay_read_errors(mddev, rdev); + atomic_inc(&rdev->read_errors); + cur_read_error_count = atomic_read(&rdev->read_errors); + if (cur_read_error_count > max_read_errors) { + rcu_read_unlock(); + printk(KERN_NOTICE + "raid10: %s: Raid device exceeded " + "read_error threshold " + "[cur %d:max %d]\n", + b, cur_read_error_count, max_read_errors); + printk(KERN_NOTICE + "raid10: %s: Failing raid " + "device\n", b); + md_error(mddev, conf->mirrors[d].rdev); + return; + } + } + rcu_read_unlock(); + while(sectors) { int s = sectors; int sl = r10_bio->read_slot;