diff options
| -rw-r--r-- | block/qed-l2-cache.c | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/block/qed-l2-cache.c b/block/qed-l2-cache.c index 02b81a2..e9b2aae 100644 --- a/block/qed-l2-cache.c +++ b/block/qed-l2-cache.c @@ -161,11 +161,25 @@ void qed_commit_l2_cache_entry(L2TableCache *l2_cache, CachedL2Table *l2_table) return; } + /* Evict an unused cache entry so we have space. If all entries are in use + * we can grow the cache temporarily and we try to shrink back down later. + */ if (l2_cache->n_entries >= MAX_L2_CACHE_SIZE) { - entry = QTAILQ_FIRST(&l2_cache->entries); - QTAILQ_REMOVE(&l2_cache->entries, entry, node); - l2_cache->n_entries--; - qed_unref_l2_cache_entry(entry); + CachedL2Table *next; + QTAILQ_FOREACH_SAFE(entry, &l2_cache->entries, node, next) { + if (entry->ref > 1) { + continue; + } + + QTAILQ_REMOVE(&l2_cache->entries, entry, node); + l2_cache->n_entries--; + qed_unref_l2_cache_entry(entry); + + /* Stop evicting when we've shrunk back to max size */ + if (l2_cache->n_entries < MAX_L2_CACHE_SIZE) { + break; + } + } } l2_cache->n_entries++; |