Unify profiling SHOW code and INFORMATION_SCHEMA code for

profiling.  Also,

Bug#26938: profiling client hang if used before enabled

In the SHOW command, not sending header data because we had no 
rows to send was a protocol violation.  Porting the SHOW PROFILE
command to use the Information Schema table avoids that problem.


mysql-test/r/profiling.result:
  Add headers of pre-profile SHOW test.
mysql-test/t/profiling.test:
  Verify that the protocol isn't violated if we ask for profiling 
  info before profiling has recorded anything.
sql/sql_parse.cc:
  Remove SQLCOM_SHOW_PROFILE and add a I_S schema table entry.
sql/sql_profile.cc:
  Add SHOW column-names and a new function that takes profile options
  set in the parser and packs a list of selected fields from the 
  I_S table implementation.
sql/sql_profile.h:
  Remove unused functions and add a new function.
sql/sql_show.cc:
  Add a pointer to the function that selects fields from I_S table
  for SHOW command.
sql/sql_yacc.yy:
  Prepare an I_S table for SHOW PROFILE.
sql/table.h:
  Rename to match the intention.

mysql-test/r/profiling.result

@@ -1,3 +1,7 @@
+show profiles;
+Query_ID	Duration	Query
+show profile all;
+Status	Duration	CPU_user	CPU_system	Context_voluntary	Context_involuntary	Block_ops_in	Block_ops_out	Messages_sent	Messages_received	Page_faults_major	Page_faults_minor	Swaps	Source_function	Source_file	Source_line
 show session variables like 'profil%';
 Variable_name	Value
 profiling	OFF

mysql-test/t/profiling.test

@@ -1,3 +1,8 @@
+# Verify that the protocol isn't violated if we ask for profiling info
+# before profiling has recorded anything.
+show profiles;
+show profile all;
+
 # default is OFF
 show session variables like 'profil%';
 select @@profiling;

sql/sql_parse.cc

@@ -2315,6 +2315,15 @@ int prepare_schema_table(THD *thd, LEX *lex, Table_ident *table_ident,
       break;
     }
 #endif
+  case SCH_PROFILES:
+    /* 
+      Mark this current profiling record to be discarded.  We don't
+      wish to have SHOW commands show up in profiling.
+    */
+#ifdef ENABLED_PROFILING
+    thd->profiling.discard();
+#endif
+    break;
   case SCH_OPEN_TABLES:
   case SCH_VARIABLES:
   case SCH_STATUS:
@@ -2755,23 +2764,6 @@ mysql_execute_command(THD *thd)
 #else
     my_error(ER_FEATURE_DISABLED, MYF(0), "SHOW PROFILES", "enable-profiling");
     goto error;
-#endif
-    break;
-  }
-  case SQLCOM_SHOW_PROFILE:
-  {
-#ifdef ENABLED_PROFILING
-    thd->profiling.store();
-    thd->profiling.discard(); // will get re-enabled by reset()
-    if (lex->profile_query_id != 0)
-      res= thd->profiling.show(lex->profile_options, lex->profile_query_id);
-    else
-      res= thd->profiling.show_last(lex->profile_options);
-    if (res)
-      goto error;
-#else
-    my_error(ER_FEATURE_DISABLED, MYF(0), "SHOW PROFILE", "enable-profiling");
-    goto error;
 #endif
     break;
   }

sql/sql_profile.cc

@@ -41,27 +41,77 @@ int fill_query_profile_statistics_info(THD *thd, struct st_table_list *tables,
 ST_FIELD_INFO query_profile_statistics_info[]=
 {
   /* name, length, type, value, maybe_null, old_name */
-  {"QUERY_ID", 20, MYSQL_TYPE_LONG, 0, false, NULL},
+  {"QUERY_ID", 20, MYSQL_TYPE_LONG, 0, false, "Query_id"},
-  {"SEQ", 20, MYSQL_TYPE_LONG, 0, false, NULL},
+  {"SEQ", 20, MYSQL_TYPE_LONG, 0, false, "Seq"},
-  {"STATE", 30, MYSQL_TYPE_STRING, 0, false, NULL},
+  {"STATE", 30, MYSQL_TYPE_STRING, 0, false, "Status"},
-  {"DURATION", TIME_FLOAT_DIGITS, MYSQL_TYPE_DOUBLE, 0, false, NULL},
+  {"DURATION", TIME_FLOAT_DIGITS, MYSQL_TYPE_DOUBLE, 0, false, "Duration"},
-  {"CPU_USER", TIME_FLOAT_DIGITS, MYSQL_TYPE_DOUBLE, 0, true, NULL},
+  {"CPU_USER", TIME_FLOAT_DIGITS, MYSQL_TYPE_DOUBLE, 0, true, "CPU_user"},
-  {"CPU_SYSTEM", TIME_FLOAT_DIGITS, MYSQL_TYPE_DOUBLE, 0, true, NULL},
+  {"CPU_SYSTEM", TIME_FLOAT_DIGITS, MYSQL_TYPE_DOUBLE, 0, true, "CPU_system"},
-  {"CONTEXT_VOLUNTARY", 20, MYSQL_TYPE_LONG, 0, true, NULL},
+  {"CONTEXT_VOLUNTARY", 20, MYSQL_TYPE_LONG, 0, true, "Context_voluntary"},
-  {"CONTEXT_INVOLUNTARY", 20, MYSQL_TYPE_LONG, 0, true, NULL},
+  {"CONTEXT_INVOLUNTARY", 20, MYSQL_TYPE_LONG, 0, true, "Context_involuntary"},
-  {"BLOCK_OPS_IN", 20, MYSQL_TYPE_LONG, 0, true, NULL},
+  {"BLOCK_OPS_IN", 20, MYSQL_TYPE_LONG, 0, true, "Block_ops_in"},
-  {"BLOCK_OPS_OUT", 20, MYSQL_TYPE_LONG, 0, true, NULL},
+  {"BLOCK_OPS_OUT", 20, MYSQL_TYPE_LONG, 0, true, "Block_ops_out"},
-  {"MESSAGES_SENT", 20, MYSQL_TYPE_LONG, 0, true, NULL},
+  {"MESSAGES_SENT", 20, MYSQL_TYPE_LONG, 0, true, "Messages_sent"},
-  {"MESSAGES_RECEIVED", 20, MYSQL_TYPE_LONG, 0, true, NULL},
+  {"MESSAGES_RECEIVED", 20, MYSQL_TYPE_LONG, 0, true, "Messages_received"},
-  {"PAGE_FAULTS_MAJOR", 20, MYSQL_TYPE_LONG, 0, true, NULL},
+  {"PAGE_FAULTS_MAJOR", 20, MYSQL_TYPE_LONG, 0, true, "Page_faults_major"},
-  {"PAGE_FAULTS_MINOR", 20, MYSQL_TYPE_LONG, 0, true, NULL},
+  {"PAGE_FAULTS_MINOR", 20, MYSQL_TYPE_LONG, 0, true, "Page_faults_minor"},
-  {"SWAPS", 20, MYSQL_TYPE_LONG, 0, true, NULL},
+  {"SWAPS", 20, MYSQL_TYPE_LONG, 0, true, "Swaps"},
-  {"SOURCE_FUNCTION", 30, MYSQL_TYPE_STRING, 0, true, NULL},
+  {"SOURCE_FUNCTION", 30, MYSQL_TYPE_STRING, 0, true, "Source_function"},
-  {"SOURCE_FILE", 20, MYSQL_TYPE_STRING, 0, true, NULL},
+  {"SOURCE_FILE", 20, MYSQL_TYPE_STRING, 0, true, "Source_file"},
-  {"SOURCE_LINE", 20, MYSQL_TYPE_LONG, 0, true, NULL},
+  {"SOURCE_LINE", 20, MYSQL_TYPE_LONG, 0, true, "Source_line"},
   {NULL, 0, MYSQL_TYPE_STRING, 0, true, NULL}
 };
 
+
+int make_profile_table_for_show(THD *thd, ST_SCHEMA_TABLE *schema_table)
+{
+  int profile_options = thd->lex->profile_options;
+  int fields_include_condition_truth_values[]= {
+    FALSE, /* Query_id */
+    FALSE, /* Seq */
+    TRUE, /* Status */
+    TRUE, /* Duration */
+    profile_options & PROFILE_CPU, /* CPU_user */
+    profile_options & PROFILE_CPU, /* CPU_system */
+    profile_options & PROFILE_CONTEXT, /* Context_voluntary */
+    profile_options & PROFILE_CONTEXT, /* Context_involuntary */
+    profile_options & PROFILE_BLOCK_IO, /* Block_ops_in */
+    profile_options & PROFILE_BLOCK_IO, /* Block_ops_out */
+    profile_options & PROFILE_IPC, /* Messages_sent */
+    profile_options & PROFILE_IPC, /* Messages_received */
+    profile_options & PROFILE_PAGE_FAULTS, /* Page_faults_major */
+    profile_options & PROFILE_PAGE_FAULTS, /* Page_faults_minor */
+    profile_options & PROFILE_SWAPS, /* Swaps */
+    profile_options & PROFILE_SOURCE, /* Source_function */
+    profile_options & PROFILE_SOURCE, /* Source_file */
+    profile_options & PROFILE_SOURCE, /* Source_line */
+  };
+
+  ST_FIELD_INFO *field_info;
+  Name_resolution_context *context= &thd->lex->select_lex.context;
+  int i;
+
+  for (i= 0; schema_table->fields_info[i].field_name != NULL; i++)
+  {
+    if (! fields_include_condition_truth_values[i])
+      continue;
+
+    field_info= &schema_table->fields_info[i];
+    Item_field *field= new Item_field(context,
+                                      NullS, NullS, field_info->field_name);
+    if (field)
+    {
+      field->set_name(field_info->old_name,
+                      strlen(field_info->old_name),
+                      system_charset_info);
+      if (add_item_to_list(thd, field))
+        return 1;
+    }
+  }
+  return 0;
+}
+
+
 #ifdef ENABLED_PROFILING
 
 #define RUSAGE_USEC(tv)  ((tv).tv_sec*1000*1000 + (tv).tv_usec)
@@ -242,212 +292,6 @@ void QUERY_PROFILE::reset()
   DBUG_VOID_RETURN;
 }
 
-bool QUERY_PROFILE::show(uint options)
-{  
-  THD *thd= profiling->thd;
-  List<Item> field_list;
-  DBUG_ENTER("QUERY_PROFILE::show");
-
-  field_list.push_back(new Item_empty_string("Status", MYSQL_ERRMSG_SIZE));
-  field_list.push_back(new Item_return_int("Duration", TIME_FLOAT_DIGITS,
-                                           MYSQL_TYPE_DOUBLE));
-
-  if (options & PROFILE_CPU)
-  {
-    field_list.push_back(new Item_return_int("CPU_user", TIME_FLOAT_DIGITS,
-                                             MYSQL_TYPE_DOUBLE));
-    field_list.push_back(new Item_return_int("CPU_system", TIME_FLOAT_DIGITS, 
-                                             MYSQL_TYPE_DOUBLE));
-  }
-  
-  if (options & PROFILE_MEMORY)
-  {
-  }
-  
-  if (options & PROFILE_CONTEXT)
-  {
-    field_list.push_back(new Item_return_int("Context_voluntary", 10,
-                                             MYSQL_TYPE_LONG));
-    field_list.push_back(new Item_return_int("Context_involuntary", 10,
-                                             MYSQL_TYPE_LONG));
-  }
-
-  if (options & PROFILE_BLOCK_IO)
-  {
-    field_list.push_back(new Item_return_int("Block_ops_in", 10,
-                                             MYSQL_TYPE_LONG));
-    field_list.push_back(new Item_return_int("Block_ops_out", 10,
-                                             MYSQL_TYPE_LONG));
-  }
-  
-  if (options & PROFILE_IPC)
-  {
-    field_list.push_back(new Item_return_int("Messages_sent", 10,
-                                             MYSQL_TYPE_LONG));
-    field_list.push_back(new Item_return_int("Messages_received", 10,
-                                             MYSQL_TYPE_LONG));
-  }
-  
-  if (options & PROFILE_PAGE_FAULTS)
-  {
-    field_list.push_back(new Item_return_int("Page_faults_major", 10,
-                                             MYSQL_TYPE_LONG));
-    field_list.push_back(new Item_return_int("Page_faults_minor", 10,
-                                             MYSQL_TYPE_LONG));
-  }
-  
-  if (options & PROFILE_SWAPS)
-  {
-    field_list.push_back(new Item_return_int("Swaps", 10, MYSQL_TYPE_LONG));
-  }
-  
-  if (options & PROFILE_SOURCE)
-  {
-    field_list.push_back(new Item_empty_string("Source_function",
-                                               MYSQL_ERRMSG_SIZE));  
-    field_list.push_back(new Item_empty_string("Source_file",
-                                               MYSQL_ERRMSG_SIZE));
-    field_list.push_back(new Item_return_int("Source_line", 10,
-                                             MYSQL_TYPE_LONG));
-  }
-  
-  if (thd->protocol->send_fields(&field_list,
-                                 Protocol::SEND_NUM_ROWS | Protocol::SEND_EOF))
-    DBUG_RETURN(TRUE);
-
-  Protocol *protocol= thd->protocol;
-  SELECT_LEX *sel= &thd->lex->select_lex;
-  SELECT_LEX_UNIT *unit= &thd->lex->unit;
-  ha_rows idx= 0;
-  unit->set_limit(sel);
-  PROFILE_ENTRY *previous= &profile_start;
-
-  PROFILE_ENTRY *entry;
-  void *iterator;
-  for (iterator= entries.new_iterator(); 
-       iterator != NULL; 
-       iterator= entries.iterator_next(iterator))
-  {
-    entry= entries.iterator_value(iterator);
-
-#ifdef HAVE_GETRUSAGE
-    struct rusage *rusage= &(entry->rusage);
-#endif
-    String elapsed;
-
-    if (++idx <= unit->offset_limit_cnt)
-      continue;
-    if (idx > unit->select_limit_cnt)
-      break;
-
-    protocol->prepare_for_resend();
-
-    /*
-      This entry, n, has a point in time, T(n), and a status phrase, S(n).  The
-      status phrase S(n) describes the period of time that begins at T(n).  The
-      previous status phrase S(n-1) describes the period of time that starts at
-      T(n-1) and ends at T(n).  Since we want to describe the time that a status
-      phrase took T(n)-T(n-1), this line must describe the previous status.
-    */
-    protocol->store(previous->status, strlen(previous->status), 
-                    system_charset_info);
-    protocol->store((double)(entry->time_usecs - 
-                    previous->time_usecs)/(1000.0*1000),
-                    (uint32) TIME_FLOAT_DIGITS-1, &elapsed);
-
-    if (options & PROFILE_CPU)
-    {
-#ifdef HAVE_GETRUSAGE
-      String cpu_utime, cpu_stime;
-      protocol->store((double)(RUSAGE_DIFF_USEC(rusage->ru_utime,
-                      previous->rusage.ru_utime))/(1000.0*1000),
-                      (uint32) TIME_FLOAT_DIGITS-1, &cpu_utime);
-      protocol->store((double)(RUSAGE_DIFF_USEC(rusage->ru_stime,
-                      previous->rusage.ru_stime))/(1000.0*1000),
-                      (uint32) TIME_FLOAT_DIGITS-1, &cpu_stime);
-#else
-      protocol->store_null();
-      protocol->store_null();
-#endif
-    }
-    
-    if (options & PROFILE_CONTEXT)
-    {
-#ifdef HAVE_GETRUSAGE
-      protocol->store((uint32)(rusage->ru_nvcsw - previous->rusage.ru_nvcsw));
-      protocol->store((uint32)(rusage->ru_nivcsw - previous->rusage.ru_nivcsw));
-#else
-      protocol->store_null();
-      protocol->store_null();
-#endif
-    }
-
-    if (options & PROFILE_BLOCK_IO)
-    {
-#ifdef HAVE_GETRUSAGE
-      protocol->store((uint32)(rusage->ru_inblock - previous->rusage.ru_inblock));
-      protocol->store((uint32)(rusage->ru_oublock - previous->rusage.ru_oublock));
-#else
-      protocol->store_null();
-      protocol->store_null();
-#endif
-    }
-    
-    if (options & PROFILE_IPC)
-    {
-#ifdef HAVE_GETRUSAGE
-      protocol->store((uint32)(rusage->ru_msgsnd - previous->rusage.ru_msgsnd));
-      protocol->store((uint32)(rusage->ru_msgrcv - previous->rusage.ru_msgrcv));
-#else
-      protocol->store_null();
-      protocol->store_null();
-#endif
-    }
-    
-    if (options & PROFILE_PAGE_FAULTS)
-    {
-#ifdef HAVE_GETRUSAGE
-      protocol->store((uint32)(rusage->ru_majflt - previous->rusage.ru_majflt));
-      protocol->store((uint32)(rusage->ru_minflt - previous->rusage.ru_minflt));
-#else
-      protocol->store_null();
-      protocol->store_null();
-#endif
-    }
-
-    if (options & PROFILE_SWAPS)
-    {
-#ifdef HAVE_GETRUSAGE
-      protocol->store((uint32)(rusage->ru_nswap - previous->rusage.ru_nswap));
-#else
-      protocol->store_null();
-#endif
-    }
-    
-    if (options & PROFILE_SOURCE)
-    {
-      if ((entry->function != NULL) && (entry->file != NULL))
-      {
-        protocol->store(entry->function, strlen(entry->function),
-                        system_charset_info);        
-        protocol->store(entry->file, strlen(entry->file), system_charset_info);
-        protocol->store((uint32) entry->line);
-      } else {
-        protocol->store_null();
-        protocol->store_null();
-        protocol->store_null();
-      }
-    }
-
-    if (protocol->write())
-      DBUG_RETURN(TRUE);
-
-    previous= entry;
-  }
-  send_eof(thd);
-  DBUG_RETURN(FALSE);
-}
-
 PROFILING::PROFILING()
   :profile_id_counter(1), keeping(TRUE), enabled(FALSE), current(NULL), last(NULL)
 {
@@ -630,38 +474,11 @@ void PROFILING::set_query_source(char *query_source_arg, uint query_length_arg)
   DBUG_VOID_RETURN;
 }
 
-bool PROFILING::show(uint options, uint profiling_query_id)
-{
-  DBUG_ENTER("PROFILING::show");
-  QUERY_PROFILE *prof;
-
-  void *iterator;
-  for (iterator= history.new_iterator(); 
-       iterator != NULL; 
-       iterator= history.iterator_next(iterator))
-  {
-    prof= history.iterator_value(iterator);
-
-    if(prof->profiling_query_id == profiling_query_id)
-      DBUG_RETURN(prof->show(options));
-  }
-
-  my_error(ER_WRONG_ARGUMENTS, MYF(0), "SHOW PROFILE");
-  DBUG_RETURN(TRUE);
-}
-
-bool PROFILING::show_last(uint options)
-{
-  DBUG_ENTER("PROFILING::show_last");
-  if (!history.is_empty()) {
-    DBUG_RETURN(last->show(options));
-  }
-  DBUG_RETURN(TRUE);
-}
-
 
 /**
   Fill the information schema table, "query_profile", as defined in show.cc .
+  There are two ways to get to this function:  Selecting from the information
+  schema, and a SHOW command.  
 */
 int PROFILING::fill_statistics_info(THD *thd, struct st_table_list *tables, Item *cond)
 {
@@ -696,6 +513,31 @@ int PROFILING::fill_statistics_info(THD *thd, struct st_table_list *tables, Item
     {
       entry= query->entries.iterator_value(entry_iterator);
 
+      if (thd->lex->orig_sql_command == SQLCOM_SHOW_PROFILE)
+      {
+        /* 
+          We got here via a SHOW command.  That means that we stored
+          information about the query we wish to show and that isn't
+          in a WHERE clause at a higher level to filter out rows we
+          wish to exclude.
+
+          Because that functionality isn't available in the server yet,
+          we must filter here, at the wrong level.  Once one can con-
+          struct where and having conditions at the SQL layer, then this
+          condition should be ripped out.
+        */
+        if (thd->lex->profile_query_id == 0) /* 0 == show final query */
+        {
+          if (query != last)
+            continue;
+        }
+        else
+        {
+          if (thd->lex->profile_query_id != query->profiling_query_id)
+            continue;
+        }
+      }
+
       /* Set default values for this row. */
       restore_record(table, s->default_values);
 

sql/sql_profile.h

@@ -39,6 +39,7 @@ extern const char * const _unknown_func_;
 
 extern ST_FIELD_INFO query_profile_statistics_info[];
 int fill_query_profile_statistics_info(THD *thd, struct st_table_list *tables, Item *cond);
+int make_profile_table_for_show(THD *thd, ST_SCHEMA_TABLE *schema_table);
 
 
 #define PROFILE_NONE         0
@@ -332,12 +333,6 @@ public:
   /* SHOW PROFILES */
   bool show_profiles();
 
-  /* SHOW PROFILE FOR QUERY query_id */
-  bool show(uint options, uint profiling_query_id);
-
-  /* SHOW PROFILE */
-  bool show_last(uint options);
-
   /* ... from INFORMATION_SCHEMA.PROFILING ... */
   int fill_statistics_info(THD *thd, struct st_table_list *tables, Item *cond);
 };

sql/sql_show.cc

@@ -4344,7 +4344,8 @@ ST_SCHEMA_TABLE schema_tables[]=
   {"OPEN_TABLES", open_tables_fields_info, create_schema_table,
    fill_open_tables, make_old_format, 0, -1, -1, 1},
   {"PROFILING", query_profile_statistics_info, create_schema_table,
-    fill_query_profile_statistics_info, NULL, NULL, -1, -1, false},
+   fill_query_profile_statistics_info, make_profile_table_for_show, 
+   NULL, -1, -1, false},
   {"ROUTINES", proc_fields_info, create_schema_table, 
     fill_schema_proc, make_proc_old_format, 0, -1, -1, 0},
   {"SCHEMATA", schema_fields_info, create_schema_table,

sql/sql_yacc.yy

@@ -7044,7 +7044,13 @@ show_param:
         | PROFILES_SYM
           { Lex->sql_command = SQLCOM_SHOW_PROFILES; }
         | PROFILE_SYM opt_profile_defs opt_profile_args opt_limit_clause_init
-          { Lex->sql_command = SQLCOM_SHOW_PROFILE; }
+          { 
+            LEX *lex= Lex;
+            lex->sql_command= SQLCOM_SELECT;
+            lex->orig_sql_command= SQLCOM_SHOW_PROFILE;
+            if (prepare_schema_table(YYTHD, lex, NULL, SCH_PROFILES) != 0)
+              YYABORT;
+          }
         | opt_var_type STATUS_SYM wild_and_where
           {
             LEX *lex= Lex;

sql/table.h

@@ -320,7 +320,7 @@ enum enum_schema_tables
   SCH_COLUMN_PRIVILEGES,
   SCH_KEY_COLUMN_USAGE,
   SCH_OPEN_TABLES,
-  SCH_PROFILING,
+  SCH_PROFILES,
   SCH_PROCEDURES,
   SCH_SCHEMATA,
   SCH_SCHEMA_PRIVILEGES,