Merge error, server always flushes on eviction

Former-commit-id: 9b3b0c9a40ab5dcdac9620f0fbad84887cc9c832

src/evict.cpp

@@ -678,7 +678,7 @@ int freeMemoryIfNeeded(bool fPreSnapshot) {
     result = C_OK;
 
 cant_free:
-    if (!cserver.delete_on_evict)
+    if (!cserver.delete_on_evict && result != C_OK)
     {
         for (int idb = 0; idb < cserver.dbnum; ++idb)
         {
@@ -688,7 +688,7 @@ cant_free:
                 serverLog(LL_WARNING, "Failed to evict keys, falling back to flushing entire cache.  Consider increasing maxmemory-samples.");
                 db->removeAllCachedValues();
                 if (((mem_reported - zmalloc_used_memory()) + mem_freed) >= mem_tofree)
-                    return C_OK;
+                    result = C_OK;
             }
         }
     }

tests/unit/flash.tcl

@@ -130,6 +130,9 @@ start_server [list tags {flash} overrides [list storage-provider {flash ./rocks.
                 } err
                 assert {$err == {OK}}
             }
+            if {[log_file_matches [srv 0 stdout] "*Failed to evict*"]} {
+                fail "Server did not evict cleanly (detected full flush)"
+            }
             r set last val
             set dbsize [r dbsize]
             assert {[s used_memory] < $limit+4096}