From bf157ed833f8732c4e264422bd8be46fdf75673a Mon Sep 17 00:00:00 2001 From: Zdenek Kabelac Date: Sun, 18 Dec 2016 15:05:57 +0100 Subject: [PATCH] cache: improve wait for cache clear Avoid printing misleading message about single dirty block. Instead properly detect condition where the 'cleaner' policy needs to be installed without 'overloading' dirty variable. Also print warning if we would be clearing read-only volume. (it really shouldn't happen). --- WHATS_NEW | 1 + lib/metadata/cache_manip.c | 17 ++++++++++------- 2 files changed, 11 insertions(+), 7 deletions(-) diff --git a/WHATS_NEW b/WHATS_NEW index 50023082c..2e9c95352 100644 --- a/WHATS_NEW +++ b/WHATS_NEW @@ -1,5 +1,6 @@ Version 2.02.169 - ===================================== + Avoid shifting by one number of blocks when clearing dirty cache volume. Extend metadata validation of external origin LV use count. Fix dm table when the last user of active external origin is removed. Improve reported lvs status for active external origin volume. diff --git a/lib/metadata/cache_manip.c b/lib/metadata/cache_manip.c index d73142d34..54d907cec 100644 --- a/lib/metadata/cache_manip.c +++ b/lib/metadata/cache_manip.c @@ -383,7 +383,7 @@ int lv_cache_wait_for_clean(struct logical_volume *cache_lv, int *is_clean) const struct logical_volume *lock_lv = lv_lock_holder(cache_lv); struct lv_segment *cache_seg = first_seg(cache_lv); struct lv_status_cache *status; - int cleaner_policy; + int cleaner_policy, writeback; uint64_t dirty_blocks; *is_clean = 0; @@ -402,14 +402,11 @@ int lv_cache_wait_for_clean(struct logical_volume *cache_lv, int *is_clean) cleaner_policy = !strcmp(status->cache->policy_name, "cleaner"); dirty_blocks = status->cache->dirty_blocks; - - /* No clear policy and writeback mode means dirty */ - if (!cleaner_policy && - (status->cache->feature_flags & DM_CACHE_FEATURE_WRITEBACK)) - dirty_blocks++; + writeback = (status->cache->feature_flags & DM_CACHE_FEATURE_WRITEBACK); dm_pool_destroy(status->mem); - if (!dirty_blocks) + /* Only clear when policy is Clear or mode != writeback */ + if (!dirty_blocks && (cleaner_policy || !writeback)) break; log_print_unless_silent("Flushing " FMTu64 " blocks for cache %s.", @@ -420,6 +417,12 @@ int lv_cache_wait_for_clean(struct logical_volume *cache_lv, int *is_clean) continue; } + if (!(cache_lv->status & LVM_WRITE)) { + log_warn("WARNING: Dirty blocks found on read-only cache volume %s.", + display_lvname(cache_lv)); + /* TODO: can we actually clean something? */ + } + /* Switch to cleaner policy to flush the cache */ cache_seg->cleaner_policy = 1; /* Reaload kernel with "cleaner" policy */ -- 2.43.5