From: Mark Nelson <mnelson@redhat.com>
Date: Fri, 24 Jul 2020 05:29:15 +0000 (+0000)
Subject: mds/CInode: Optimize only pinned by subtrees check
X-Git-Tag: v15.2.9~122^2~24^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=f8a777016e7f741c06f75edc65ab8b7f25de3798;p=ceph.git

mds/CInode: Optimize only pinned by subtrees check

Fixes: https://tracker.ceph.com/issues/46727

Signed-off-by: Mark Nelson <mnelson@redhat.com>
(cherry picked from commit 6a865f805b723525358ed8e79bb3d41709e98bf3)
---

diff --git a/src/mds/CInode.h b/src/mds/CInode.h
index 22cdc6e7bef3..b5d6465cc1f3 100644
--- a/src/mds/CInode.h
+++ b/src/mds/CInode.h
@@ -575,6 +575,9 @@ class CInode : public MDSCacheObject, public InodeStoreBase, public Counter<CIno
     get_subtree_dirfrags(v);
     return v;
   }
+  int get_num_subtree_roots() const {
+    return num_subtree_roots;
+  }
 
   CDir *get_or_open_dirfrag(MDCache *mdcache, frag_t fg);
   CDir *add_dirfrag(CDir *dir);
diff --git a/src/mds/MDCache.cc b/src/mds/MDCache.cc
index 88eece19f00b..d131edccb878 100644
--- a/src/mds/MDCache.cc
+++ b/src/mds/MDCache.cc
@@ -6819,9 +6819,9 @@ std::pair<bool, uint64_t> MDCache::trim(uint64_t count)
       }
     } else if (!diri->is_auth() && dir->get_num_ref() <= 1) {
       // only subtree pin
-      auto&& ls = diri->get_subtree_dirfrags();
-      if (diri->get_num_ref() > (int)ls.size()) // only pinned by subtrees
+      if (diri->get_num_ref() > diri->get_num_subtree_roots()) {
         continue;
+      }
 
       // don't trim subtree root if its auth MDS is recovering.
       // This simplify the cache rejoin code.