MWL#182: Explain running statements: address review feedback

- Move standalone tests to a unittest.
- Added comments.

CMakeLists.txt

@@ -279,6 +279,7 @@ IF(WITH_UNIT_TESTS)
  ADD_SUBDIRECTORY(unittest/strings)
  ADD_SUBDIRECTORY(unittest/examples)
  ADD_SUBDIRECTORY(unittest/mysys)
+ ADD_SUBDIRECTORY(unittest/sql)
 ENDIF()
 
 IF(NOT WITHOUT_SERVER)

sql/my_apc.cc

@@ -15,22 +15,13 @@
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
 
 
-#ifdef MY_APC_STANDALONE
-
-#include <my_global.h>
-#include <my_pthread.h>
-#include <my_sys.h>
-
-#include "my_apc.h"
-
-#else
+#ifndef MY_APC_STANDALONE
 
 #include "sql_priv.h"
 #include "sql_class.h"
 
 #endif
 
-
 /*
   Standalone testing:
     g++ -c -DMY_APC_STANDALONE -g -I.. -I../include -o my_apc.o my_apc.cc
@@ -141,11 +132,18 @@ void Apc_target::dequeue_request(Call_request *qe)
 /*
   Make an APC (Async Procedure Call) to another thread. 
  
-  - The caller is responsible for making sure he's not calling to the same
-    thread.
+  @detail
+  Make an APC call: schedule it for execution and wait until the target
+  thread has executed it. 
+
+  - The caller is responsible for making sure he's not posting request
+    to the thread he's calling this function from.
 
-  - The caller should have locked target_thread_mutex.
+  - The caller must have locked target_mutex. The function will release it.
 
+  @retval FALSE - Ok, the call has been made
+  @retval TRUE  - Call wasnt made (either the target is in disabled state or
+                    timeout occured)
 
   psergey-todo: Should waits here be KILLable? (it seems one needs 
   to use thd->enter_cond() calls to be killable)
@@ -251,137 +249,3 @@ void Apc_target::process_apc_requests()
   }
 }
 
-/*****************************************************************************
- * Testing 
- *****************************************************************************/
-#ifdef MY_APC_STANDALONE
-
-volatile bool started= FALSE;
-volatile bool service_should_exit= FALSE;
-volatile bool requestors_should_exit=FALSE;
-
-volatile int apcs_served= 0;
-volatile int apcs_missed=0;
-volatile int apcs_timed_out=0;
-
-Apc_target apc_target;
-mysql_mutex_t target_mutex;
-
-int int_rand(int size)
-{
-  return round (((double)rand() / RAND_MAX) * size);
-}
-
-/* An APC-serving thread */
-void *test_apc_service_thread(void *ptr)
-{
-  my_thread_init();
-  mysql_mutex_init(0, &target_mutex, MY_MUTEX_INIT_FAST);
-  apc_target.init(&target_mutex);
-  apc_target.enable();
-  started= TRUE;
-  fprintf(stderr, "# test_apc_service_thread started\n");
-  while (!service_should_exit)
-  {
-    //apc_target.disable();
-    usleep(10000);
-    //apc_target.enable();
-    for (int i = 0; i < 10 && !service_should_exit; i++)
-    {
-      apc_target.process_apc_requests();
-      usleep(int_rand(30));
-    }
-  }
-  apc_target.disable();
-  apc_target.destroy();
-  my_thread_end();
-  pthread_exit(0);
-}
-
-class Apc_order
-{
-public:
-  int value;   // The value 
-  int *where_to;  // Where to write it
-  Apc_order(int a, int *b) : value(a), where_to(b) {}
-};
-
-void test_apc_func(void *arg)
-{
-  Apc_order *order=(Apc_order*)arg;
-  usleep(int_rand(1000));
-  *(order->where_to) = order->value;
-  __sync_fetch_and_add(&apcs_served, 1);
-}
-
-void *test_apc_requestor_thread(void *ptr)
-{
-  my_thread_init();
-  fprintf(stderr, "# test_apc_requestor_thread started\n");
-  while (!requestors_should_exit)
-  {
-    int dst_value= 0;
-    int src_value= int_rand(4*1000*100);
-    /* Create APC to do  dst_value= src_value */
-    Apc_order apc_order(src_value, &dst_value);
-    bool timed_out;
-
-    bool res= apc_target.make_apc_call(test_apc_func, (void*)&apc_order, 60, &timed_out);
-    if (res)
-    {
-      if (timed_out)
-        __sync_fetch_and_add(&apcs_timed_out, 1);
-      else
-        __sync_fetch_and_add(&apcs_missed, 1);
-
-      if (dst_value != 0)
-        fprintf(stderr, "APC was done even though return value says it wasnt!\n");
-    }
-    else
-    {
-      if (dst_value != src_value)
-        fprintf(stderr, "APC was not done even though return value says it was!\n");
-    }
-    //usleep(300);
-  }
-  fprintf(stderr, "# test_apc_requestor_thread exiting\n");
-  my_thread_end();
-}
-
-const int N_THREADS=23;
-int main(int args, char **argv)
-{
-  pthread_t service_thr;
-  pthread_t request_thr[N_THREADS];
-  int i, j;
-  my_thread_global_init();
-
-  pthread_create(&service_thr, NULL, test_apc_service_thread, (void*)NULL);
-  while (!started)
-    usleep(1000);
-  for (i = 0; i < N_THREADS; i++)
-    pthread_create(&request_thr[i], NULL, test_apc_requestor_thread, (void*)NULL);
-  
-  for (i = 0; i < 15; i++)
-  {
-    usleep(500*1000);
-    fprintf(stderr, "# %d APCs served %d missed\n", apcs_served, apcs_missed);
-  }
-  fprintf(stderr, "# Shutting down requestors\n");
-  requestors_should_exit= TRUE;
-  for (i = 0; i < N_THREADS; i++)
-    pthread_join(request_thr[i], NULL);
-  
-  fprintf(stderr, "# Shutting down service\n");
-  service_should_exit= TRUE;
-  pthread_join(service_thr, NULL);
-  fprintf(stderr, "# Done.\n");
-  my_thread_end();
-  my_thread_global_end();
-  return 0;
-}
-
-#endif // MY_APC_STANDALONE
-
-
-

sql/my_apc.h

@@ -50,21 +50,16 @@ public:
   
   void process_apc_requests();
   
+  /* Functor class for calls you can schedule */
   class Apc_call
   {
   public:
+    /* This function will be called in the target thread */
     virtual void call_in_target_thread()= 0;
     virtual ~Apc_call() {}
   };
-  /*
-    Make an APC call: schedule it for execution and wait until the target
-    thread has executed it. This function must not be called from a thread
-    that's different from the target thread.
   
-    @retval FALSE - Ok, the call has been made
-    @retval TRUE  - Call wasnt made (either the target is in disabled state or
-                    timeout occured)
-  */
+  /* Make a call in the target thread (see function definition for details) */
   bool make_apc_call(Apc_call *call, int timeout_sec, bool *timed_out);
 
 #ifndef DBUG_OFF

unittest/sql/CMakeLists.txt

+
+MY_ADD_TESTS(my_apc LINK_LIBRARIES mysys EXT cc)
+

unittest/sql/my_apc-t.cc

+/*
+   Copyright (c) 2012, Monty Program Ab
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; version 2 of the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
+
+/*
+  This file does standalone APC system tests.
+*/
+#include <stdio.h>
+#include <my_global.h>
+#include <my_pthread.h>
+#include <my_sys.h>
+
+#include <tap.h>
+
+#include "../sql/my_apc.h"
+
+#define MY_APC_STANDALONE 1
+#include "../sql/my_apc.cc"
+
+volatile bool started= FALSE;
+volatile bool service_should_exit= FALSE;
+volatile bool requestors_should_exit=FALSE;
+
+/*  Counters for APC calls */
+int apcs_served= 0;
+int apcs_missed=0;
+int apcs_timed_out=0;
+mysql_mutex_t apc_counters_mutex;
+
+inline void increment_counter(int *var)
+{
+  mysql_mutex_lock(&apc_counters_mutex);
+  *var= *var+1;
+  mysql_mutex_unlock(&apc_counters_mutex);
+}
+
+volatile bool have_errors= false;
+
+Apc_target apc_target;
+mysql_mutex_t target_mutex;
+
+int int_rand(int size)
+{
+  return round (((double)rand() / RAND_MAX) * size);
+}
+
+/* 
+  APC target thread (the one that will serve the APC requests). We will have
+  one target.
+*/
+void *test_apc_service_thread(void *ptr)
+{
+  my_thread_init();
+  mysql_mutex_init(0, &target_mutex, MY_MUTEX_INIT_FAST);
+  apc_target.init(&target_mutex);
+  apc_target.enable();
+  started= TRUE;
+  fprintf(stderr, "# test_apc_service_thread started\n");
+  while (!service_should_exit)
+  {
+    //apc_target.disable();
+    usleep(10000);
+    //apc_target.enable();
+    for (int i = 0; i < 10 && !service_should_exit; i++)
+    {
+      apc_target.process_apc_requests();
+      usleep(int_rand(30));
+    }
+  }
+  apc_target.disable();
+  apc_target.destroy();
+  mysql_mutex_destroy(&target_mutex);
+  my_thread_end();
+  pthread_exit(0);
+}
+
+
+/*
+  One APC request (to write 'value' into *where_to)
+*/
+class Apc_order : public Apc_target::Apc_call
+{
+public:
+  int value;   // The value 
+  int *where_to;  // Where to write it
+  Apc_order(int a, int *b) : value(a), where_to(b) {}
+
+  void call_in_target_thread()
+  {
+    usleep(int_rand(1000));
+    *where_to = value;
+    increment_counter(&apcs_served);
+  }
+};
+
+
+/*
+  APC requestor thread. It makes APC requests, and checks if they were actually
+  executed.
+*/
+void *test_apc_requestor_thread(void *ptr)
+{
+  my_thread_init();
+  fprintf(stderr, "# test_apc_requestor_thread started\n");
+  while (!requestors_should_exit)
+  {
+    int dst_value= 0;
+    int src_value= int_rand(4*1000*100);
+    /* Create an APC to do "dst_value= src_value" assignment */
+    Apc_order apc_order(src_value, &dst_value);
+    bool timed_out;
+
+    mysql_mutex_lock(&target_mutex);
+    bool res= apc_target.make_apc_call(&apc_order, 60, &timed_out);
+    if (res)
+    {
+      if (timed_out)
+        increment_counter(&apcs_timed_out);
+      else
+        increment_counter(&apcs_missed);
+
+      if (dst_value != 0)
+      {
+        fprintf(stderr, "APC was done even though return value says it wasnt!\n");
+        have_errors= true;
+      }
+    }
+    else
+    {
+      if (dst_value != src_value)
+      {
+        fprintf(stderr, "APC was not done even though return value says it was!\n");
+        have_errors= true;
+      }
+    }
+    //usleep(300);
+  }
+  fprintf(stderr, "# test_apc_requestor_thread exiting\n");
+  my_thread_end();
+  return NULL;
+}
+
+/* Number of APC requestor threads */
+const int N_THREADS=23;
+
+
+int main(int args, char **argv)
+{
+  pthread_t service_thr;
+  pthread_t request_thr[N_THREADS];
+  int i;
+
+  my_thread_global_init();
+
+  mysql_mutex_init(0, &apc_counters_mutex, MY_MUTEX_INIT_FAST);
+
+  plan(1);
+  diag("Testing APC delivery and execution");
+
+  pthread_create(&service_thr, NULL, test_apc_service_thread, (void*)NULL);
+  while (!started)
+    usleep(1000);
+  for (i = 0; i < N_THREADS; i++)
+    pthread_create(&request_thr[i], NULL, test_apc_requestor_thread, (void*)NULL);
+  
+  for (i = 0; i < 15; i++)
+  {
+    usleep(500*1000);
+    fprintf(stderr, "# %d APCs served %d missed\n", apcs_served, apcs_missed);
+  }
+  fprintf(stderr, "# Shutting down requestors\n");
+  requestors_should_exit= TRUE;
+  for (i = 0; i < N_THREADS; i++)
+    pthread_join(request_thr[i], NULL);
+  
+  fprintf(stderr, "# Shutting down service\n");
+  service_should_exit= TRUE;
+  pthread_join(service_thr, NULL);
+
+  mysql_mutex_destroy(&apc_counters_mutex);
+
+  fprintf(stderr, "# Done.\n");
+  my_thread_end();
+  my_thread_global_end();
+
+  ok1(!have_errors);
+  return exit_status();
+}
+