From 72a23c211e4587859d5bf61ac4962d76e593fb02 Mon Sep 17 00:00:00 2001 From: Neil Brown Date: Sat, 28 Jun 2008 08:31:41 +1000 Subject: [PATCH] Make sure all changes to md/sync_action are notified. When the 'resync' thread starts or stops, when we explicitly set sync_action, or when we determine that there is definitely nothing to do, we notify sync_action. To stop "sync_action" from occasionally showing the wrong value, we introduce a new flags - MD_RECOVERY_RECOVER - to say that a recovery is probably needed or happening, and we make sure that we set MD_RECOVERY_RUNNING before clearing MD_RECOVERY_NEEDED. Signed-off-by: Neil Brown --- Documentation/md.txt | 6 ++++++ drivers/md/md.c | 34 ++++++++++++++++++++++++++++------ include/linux/raid/md_k.h | 2 ++ 3 files changed, 36 insertions(+), 6 deletions(-) diff --git a/Documentation/md.txt b/Documentation/md.txt index dca97ba4944a..c05bfb55659e 100644 --- a/Documentation/md.txt +++ b/Documentation/md.txt @@ -386,6 +386,12 @@ also have 'check' and 'repair' will start the appropriate process providing the current state is 'idle'. + This file responds to select/poll. Any important change in the value + triggers a poll event. Sometimes the value will briefly be + "recover" if a recovery seems to be needed, but cannot be + achieved. In that case, the transition to "recover" isn't + notified, but the transition away is. + mismatch_count When performing 'check' and 'repair', and possibly when performing 'resync', md will count the number of errors that are diff --git a/drivers/md/md.c b/drivers/md/md.c index 5b9d4fe4e6e4..c26dcad8a3ac 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -169,7 +169,6 @@ void md_new_event(mddev_t *mddev) { atomic_inc(&md_event_count); wake_up(&md_event_waiters); - sysfs_notify(&mddev->kobj, NULL, "sync_action"); } EXPORT_SYMBOL_GPL(md_new_event); @@ -2936,7 +2935,7 @@ action_show(mddev_t *mddev, char *page) type = "check"; else type = "repair"; - } else + } else if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery)) type = "recover"; } return sprintf(page, "%s\n", type); @@ -2958,9 +2957,12 @@ action_store(mddev_t *mddev, const char *page, size_t len) } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) || test_bit(MD_RECOVERY_NEEDED, &mddev->recovery)) return -EBUSY; - else if (cmd_match(page, "resync") || cmd_match(page, "recover")) + else if (cmd_match(page, "resync")) + set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); + else if (cmd_match(page, "recover")) { + set_bit(MD_RECOVERY_RECOVER, &mddev->recovery); set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); - else if (cmd_match(page, "reshape")) { + } else if (cmd_match(page, "reshape")) { int err; if (mddev->pers->start_reshape == NULL) return -EINVAL; @@ -2977,6 +2979,7 @@ action_store(mddev_t *mddev, const char *page, size_t len) } set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); md_wakeup_thread(mddev->thread); + sysfs_notify(&mddev->kobj, NULL, "sync_action"); return len; } @@ -3682,6 +3685,7 @@ static int do_md_run(mddev_t * mddev) mddev->changed = 1; md_new_event(mddev); sysfs_notify(&mddev->kobj, NULL, "array_state"); + sysfs_notify(&mddev->kobj, NULL, "sync_action"); kobject_uevent(&mddev->gendisk->dev.kobj, KOBJ_CHANGE); return 0; } @@ -4252,6 +4256,8 @@ static int add_new_disk(mddev_t * mddev, mdu_disk_info_t *info) export_rdev(rdev); md_update_sb(mddev, 1); + if (mddev->degraded) + set_bit(MD_RECOVERY_RECOVER, &mddev->recovery); set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); md_wakeup_thread(mddev->thread); return err; @@ -5105,6 +5111,8 @@ void md_error(mddev_t *mddev, mdk_rdev_t *rdev) if (!mddev->pers->error_handler) return; mddev->pers->error_handler(mddev,rdev); + if (mddev->degraded) + set_bit(MD_RECOVERY_RECOVER, &mddev->recovery); set_bit(MD_RECOVERY_INTR, &mddev->recovery); set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); md_wakeup_thread(mddev->thread); @@ -6055,13 +6063,18 @@ void md_check_recovery(mddev_t *mddev) mddev->recovery = 0; /* flag recovery needed just to double check */ set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); + sysfs_notify(&mddev->kobj, NULL, "sync_action"); md_new_event(mddev); goto unlock; } + /* Set RUNNING before clearing NEEDED to avoid + * any transients in the value of "sync_action". + */ + set_bit(MD_RECOVERY_RUNNING, &mddev->recovery); + clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery); /* Clear some bits that don't mean anything, but * might be left set */ - clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery); clear_bit(MD_RECOVERY_INTR, &mddev->recovery); clear_bit(MD_RECOVERY_DONE, &mddev->recovery); @@ -6079,17 +6092,19 @@ void md_check_recovery(mddev_t *mddev) /* Cannot proceed */ goto unlock; set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); + clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery); } else if ((spares = remove_and_add_spares(mddev))) { clear_bit(MD_RECOVERY_SYNC, &mddev->recovery); clear_bit(MD_RECOVERY_CHECK, &mddev->recovery); + set_bit(MD_RECOVERY_RECOVER, &mddev->recovery); } else if (mddev->recovery_cp < MaxSector) { set_bit(MD_RECOVERY_SYNC, &mddev->recovery); + clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery); } else if (!test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) /* nothing to be done ... */ goto unlock; if (mddev->pers->sync_request) { - set_bit(MD_RECOVERY_RUNNING, &mddev->recovery); if (spares && mddev->bitmap && ! mddev->bitmap->file) { /* We are adding a device or devices to an array * which has the bitmap stored on all devices. @@ -6108,9 +6123,16 @@ void md_check_recovery(mddev_t *mddev) mddev->recovery = 0; } else md_wakeup_thread(mddev->sync_thread); + sysfs_notify(&mddev->kobj, NULL, "sync_action"); md_new_event(mddev); } unlock: + if (!mddev->sync_thread) { + clear_bit(MD_RECOVERY_RUNNING, &mddev->recovery); + if (test_and_clear_bit(MD_RECOVERY_RECOVER, + &mddev->recovery)) + sysfs_notify(&mddev->kobj, NULL, "sync_action"); + } mddev_unlock(mddev); } } diff --git a/include/linux/raid/md_k.h b/include/linux/raid/md_k.h index 780e0613e6d5..62aa9c9a6ddc 100644 --- a/include/linux/raid/md_k.h +++ b/include/linux/raid/md_k.h @@ -188,6 +188,7 @@ struct mddev_s * NEEDED: we might need to start a resync/recover * RUNNING: a thread is running, or about to be started * SYNC: actually doing a resync, not a recovery + * RECOVER: doing recovery, or need to try it. * INTR: resync needs to be aborted for some reason * DONE: thread is done and is waiting to be reaped * REQUEST: user-space has requested a sync (used with SYNC) @@ -198,6 +199,7 @@ struct mddev_s */ #define MD_RECOVERY_RUNNING 0 #define MD_RECOVERY_SYNC 1 +#define MD_RECOVERY_RECOVER 2 #define MD_RECOVERY_INTR 3 #define MD_RECOVERY_DONE 4 #define MD_RECOVERY_NEEDED 5 -- 2.20.1