From 9750061d5d4236aaba156d60790e0b8bcd7cfb64 Mon Sep 17 00:00:00 2001
From: David Zafman <dzafman@redhat.com>
Date: Sat, 13 Apr 2019 11:32:19 -0700
Subject: [PATCH] mgr: Improve ok-to-stop by using the avail_no_missing for
 recovery

Signed-off-by: David Zafman <dzafman@redhat.com>
---
 src/mgr/DaemonServer.cc | 56 +++++++++++++++++++++++------------------
 1 file changed, 31 insertions(+), 25 deletions(-)

diff --git a/src/mgr/DaemonServer.cc b/src/mgr/DaemonServer.cc
index 0c47cfcd2ee..141d9b97761 100644
--- a/src/mgr/DaemonServer.cc
+++ b/src/mgr/DaemonServer.cc
@@ -1505,7 +1505,7 @@ bool DaemonServer::_handle_command(
       cmdctx->reply(r, ss);
       return true;
     }
-    map<pg_t,int> pg_delta;  // pgid -> net acting set size change
+    int touched_pgs = 0;
     int dangerous_pgs = 0;
     cluster_state.with_osdmap_and_pgmap([&](const OSDMap& osdmap, const PGMap& pg_map) {
 	if (pg_map.num_pg_unknown > 0) {
@@ -1514,35 +1514,40 @@ bool DaemonServer::_handle_command(
 	  r = -EAGAIN;
 	  return;
 	}
-	for (auto osd : osds) {
-	  auto p = pg_map.pg_by_osd.find(osd);
-	  if (p != pg_map.pg_by_osd.end()) {
-	    for (auto& pgid : p->second) {
-	      --pg_delta[pgid];
+	for (const auto& q : pg_map.pg_stat) {
+          set<int32_t> pg_acting;  // net acting sets (with no missing if degraded)
+	  bool found = false;
+	  if (q.second.state & PG_STATE_DEGRADED) {
+	    for (auto& anm : q.second.avail_no_missing) {
+	      if (osds.count(anm.osd)) {
+		found = true;
+		continue;
+	      }
+	      pg_acting.insert(anm.osd);
+	    }
+	  } else {
+	    for (auto& a : q.second.acting) {
+	      if (osds.count(a)) {
+		found = true;
+		continue;
+	      }
+	      pg_acting.insert(a);
 	    }
 	  }
-	}
-	for (auto& p : pg_delta) {
-	  auto q = pg_map.pg_stat.find(p.first);
-	  if (q == pg_map.pg_stat.end()) {
-	    ss << "missing information about " << p.first << "; cannot draw"
-	       << " any conclusions";
-	    r = -EAGAIN;
-	    return;
+	  if (!found) {
+	    continue;
 	  }
-	  if (!(q->second.state & PG_STATE_ACTIVE) ||
-	      (q->second.state & PG_STATE_DEGRADED)) {
-	    // we don't currently have a good way to tell *how* degraded
-	    // a degraded PG is, so we have to assume we cannot remove
-	    // any more replicas/shards.
+	  touched_pgs++;
+	  if (!(q.second.state & PG_STATE_ACTIVE) ||
+	      (q.second.state & PG_STATE_DEGRADED)) {
 	    ++dangerous_pgs;
 	    continue;
 	  }
-	  const pg_pool_t *pi = osdmap.get_pg_pool(p.first.pool());
+	  const pg_pool_t *pi = osdmap.get_pg_pool(q.first.pool());
 	  if (!pi) {
 	    ++dangerous_pgs; // pool is creating or deleting
 	  } else {
-	    if (q->second.acting.size() + p.second < pi->min_size) {
+	    if (pg_acting.size() < pi->min_size) {
 	      ++dangerous_pgs;
 	    }
 	  }
@@ -1553,14 +1558,15 @@ bool DaemonServer::_handle_command(
       return true;
     }
     if (dangerous_pgs) {
-      ss << dangerous_pgs << " PGs are already degraded or might become "
-	 << "unavailable";
+      ss << dangerous_pgs << " PGs are already too degraded, would become"
+	 << " too degraded or might become unavailable";
       cmdctx->reply(-EBUSY, ss);
       return true;
     }
     ss << "OSD(s) " << osds << " are ok to stop without reducing"
-       << " availability, provided there are no other concurrent failures"
-       << " or interventions. " << pg_delta.size() << " PGs are likely to be"
+       << " availability or risking data, provided there are no other concurrent failures"
+       << " or interventions." << std::endl;
+    ss << touched_pgs << " PGs are likely to be"
        << " degraded (but remain available) as a result.";
     cmdctx->reply(0, ss);
     return true;
-- 
2.39.5