Close databases on benchmark error exits in db_bench (#7327)

Summary:
Delete database instances to make sure there are no loose threads
running before exit(). This fixes segfaults seen when running
workloads through CompositeEnvs with custom file systems.

For further background on the issues arising when using CompositeEnvs, see the discussion in:
https://github.com/facebook/rocksdb/pull/6878

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7327

Reviewed By: cheng-chang

Differential Revision: D23433244

Pulled By: ajkr

fbshipit-source-id: 4e19cf2067e3fe68c2a3fe1823f24b4091336bbe

tools/db_bench_tool.cc

@@ -2900,9 +2900,17 @@ class Benchmark {
     fprintf(stderr, "...Verified\n");
   }
 
+  void ErrorExit() {
+    db_.DeleteDBs();
+    for (size_t i = 0; i < multi_dbs_.size(); i++) {
+      delete multi_dbs_[i].db;
+    }
+    exit(1);
+  }
+
   void Run() {
     if (!SanityCheck()) {
-      exit(1);
+      ErrorExit();
     }
     Open(&open_options_);
     PrintHeader();
@@ -2941,7 +2949,7 @@ class Benchmark {
         auto it = name.find('[');
         if (it == std::string::npos) {
           fprintf(stderr, "unknown benchmark arguments '%s'\n", name.c_str());
-          exit(1);
+          ErrorExit();
         }
         std::string args = name.substr(it + 1);
         args.resize(args.size() - 1);
@@ -2974,7 +2982,7 @@ class Benchmark {
           fprintf(stderr,
                   "Please disable_auto_compactions in FillDeterministic "
                   "benchmark\n");
-          exit(1);
+          ErrorExit();
         }
         if (num_threads > 1) {
           fprintf(stderr,
@@ -3026,7 +3034,7 @@ class Benchmark {
           fprintf(stderr,
                   "Please set use_existing_keys to true and specify a "
                   "row cache size in readtorowcache benchmark\n");
-          exit(1);
+          ErrorExit();
         }
         method = &Benchmark::ReadToRowCache;
       } else if (name == "readtocache") {
@@ -3091,7 +3099,7 @@ class Benchmark {
         if (FLAGS_merge_operator.empty()) {
           fprintf(stdout, "%-12s : skipped (--merge_operator is unknown)\n",
                   name.c_str());
-          exit(1);
+          ErrorExit();
         }
         method = &Benchmark::ReadRandomMergeRandom;
       } else if (name == "updaterandom") {
@@ -3157,18 +3165,18 @@ class Benchmark {
       } else if (name == "replay") {
         if (num_threads > 1) {
           fprintf(stderr, "Multi-threaded replay is not yet supported\n");
-          exit(1);
+          ErrorExit();
         }
         if (FLAGS_trace_file == "") {
           fprintf(stderr, "Please set --trace_file to be replayed from\n");
-          exit(1);
+          ErrorExit();
         }
         method = &Benchmark::Replay;
       } else if (name == "getmergeoperands") {
         method = &Benchmark::GetMergeOperands;
       } else if (!name.empty()) {  // No error message for empty name
         fprintf(stderr, "unknown benchmark '%s'\n", name.c_str());
-        exit(1);
+        ErrorExit();
       }
 
       if (fresh_db) {
@@ -3209,13 +3217,13 @@ class Benchmark {
           if (!s.ok()) {
             fprintf(stderr, "Encountered an error starting a trace, %s\n",
                     s.ToString().c_str());
-            exit(1);
+            ErrorExit();
           }
           s = db_.db->StartTrace(trace_options_, std::move(trace_writer));
           if (!s.ok()) {
             fprintf(stderr, "Encountered an error starting a trace, %s\n",
                     s.ToString().c_str());
-            exit(1);
+            ErrorExit();
           }
           fprintf(stdout, "Tracing the workload to: [%s]\n",
                   FLAGS_trace_file.c_str());
@@ -3227,13 +3235,13 @@ class Benchmark {
             fprintf(stderr,
                     "Block cache trace sampling frequency must be higher than "
                     "0.\n");
-            exit(1);
+            ErrorExit();
           }
           if (FLAGS_block_cache_trace_max_trace_file_size_in_bytes <= 0) {
             fprintf(stderr,
                     "The maximum file size for block cache tracing must be "
                     "higher than 0.\n");
-            exit(1);
+            ErrorExit();
           }
           block_cache_trace_options_.max_trace_file_size =
               FLAGS_block_cache_trace_max_trace_file_size_in_bytes;
@@ -3247,7 +3255,7 @@ class Benchmark {
             fprintf(stderr,
                     "Encountered an error when creating trace writer, %s\n",
                     s.ToString().c_str());
-            exit(1);
+            ErrorExit();
           }
           s = db_.db->StartBlockCacheTrace(block_cache_trace_options_,
                                            std::move(block_cache_trace_writer));
@@ -3256,7 +3264,7 @@ class Benchmark {
                 stderr,
                 "Encountered an error when starting block cache tracing, %s\n",
                 s.ToString().c_str());
-            exit(1);
+            ErrorExit();
           }
           fprintf(stdout, "Tracing block cache accesses to: [%s]\n",
                   FLAGS_block_cache_trace_file.c_str());
@@ -4575,7 +4583,7 @@ class Benchmark {
 
       if (!s.ok()) {
         fprintf(stderr, "put error: %s\n", s.ToString().c_str());
-        exit(1);
+        ErrorExit();
       }
     }
     thread->stats.AddBytes(bytes);
@@ -5663,7 +5671,7 @@ class Benchmark {
             gen.Generate(static_cast<unsigned int>(val_size)));
         if (!s.ok()) {
           fprintf(stderr, "put error: %s\n", s.ToString().c_str());
-          exit(1);
+          ErrorExit();
         }
 
         if (thread->shared->write_rate_limiter) {
@@ -6222,7 +6230,7 @@ class Benchmark {
         Status s = db->Put(write_options_, key, gen.Generate());
         if (!s.ok()) {
           fprintf(stderr, "put error: %s\n", s.ToString().c_str());
-          exit(1);
+          ErrorExit();
         }
         put_weight--;
         writes_done++;
@@ -6327,7 +6335,7 @@ class Benchmark {
       Status s = db->Put(write_options_, key, Slice(new_value));
       if (!s.ok()) {
         fprintf(stderr, "put error: %s\n", s.ToString().c_str());
-        exit(1);
+        ErrorExit();
       }
       thread->stats.FinishedOps(nullptr, db, 1);
     }
@@ -6380,7 +6388,7 @@ class Benchmark {
       Status s = db->Put(write_options_, key, value);
       if (!s.ok()) {
         fprintf(stderr, "put error: %s\n", s.ToString().c_str());
-        exit(1);
+        ErrorExit();
       }
       bytes += key.size() + value.size();
       thread->stats.FinishedOps(nullptr, db, 1, kUpdate);
@@ -6917,7 +6925,7 @@ class Benchmark {
 
       if (!s.ok()) {
         fprintf(stderr, "put error: %s\n", s.ToString().c_str());
-        exit(1);
+        ErrorExit();
       }
       bytes = key.size() + val.size();
       thread->stats.FinishedOps(&db_, db_.db, 1, kWrite);