MDEV-15359 Thread stay in "cleaning up" status after finishing

make thd_get_error_context_description() to show not just thd->proc_info, but exactly the same thread state that SHOW PROCESSLIST shows.

Author: vuvova

mysql-test/suite/plugins/r/processlist.result

@@ -0,0 +1,8 @@
+create table t1 (a int) engine=innodb;
+start transaction;
+insert t1 values (1);
+state from show engine innodb status
+ 
+state from show processlist
+
+drop table t1;

mysql-test/suite/plugins/t/processlist.test

@@ -0,0 +1,18 @@
+#
+# MDEV-15359 Thread stay in "cleaning up" status after finishing
+#
+source include/have_innodb.inc;
+
+create table t1 (a int) engine=innodb;
+start transaction;
+insert t1 values (1);
+let id=`select connection_id()`;
+connect con2,localhost,root;
+let s=query_get_value(show engine innodb status,Status,1);
+disable_query_log;
+eval select regexp_replace("$s", '(?s)^.*MySQL thread id $id,.*root([^\n]*)\n.*', '\\\\1') as `state from show engine innodb status`;
+eval select state as `state from show processlist` from information_schema.processlist where id = $id;
+enable_query_log;
+disconnect con2;
+connection default;
+drop table t1;

sql/sql_class.cc

@@ -717,103 +717,6 @@ extern "C"
 }
 
 
-/**
- Dumps a text description of a thread, its security context
- (user, host) and the current query.
-
- @param thd thread context
- @param buffer pointer to preferred result buffer
- @param length length of buffer
- @param max_query_len how many chars of query to copy (0 for all)
- 
- @return Pointer to string
-*/
-
-extern "C"
-char *thd_get_error_context_description(THD *thd, char *buffer,
- unsigned int length,
- unsigned int max_query_len)
-{
- String str(buffer, length, &my_charset_latin1);
- const Security_context *sctx= &thd->main_security_ctx;
- char header[256];
- int len;
-
- mysql_mutex_lock(&LOCK_thread_count);
-
- /*
- The pointers thd->query and thd->proc_info might change since they are
- being modified concurrently. This is acceptable for proc_info since its
- values doesn't have to very accurate and the memory it points to is static,
- but we need to attempt a snapshot on the pointer values to avoid using NULL
- values. The pointer to thd->query however, doesn't point to static memory
- and has to be protected by thd->LOCK_thd_data or risk pointing to
- uninitialized memory.
- */
- const char *proc_info= thd->proc_info;
-
- len= my_snprintf(header, sizeof(header),
- "MySQL thread id %lu, OS thread handle 0x%lx, query id %lu",
- thd->thread_id, (ulong) thd->real_id, (ulong) thd->query_id);
- str.length(0);
- str.append(header, len);
-
- if (sctx->host)
- {
- str.append(' ');
- str.append(sctx->host);
- }
-
- if (sctx->ip)
- {
- str.append(' ');
- str.append(sctx->ip);
- }
-
- if (sctx->user)
- {
- str.append(' ');
- str.append(sctx->user);
- }
-
- if (proc_info)
- {
- str.append(' ');
- str.append(proc_info);
- }
-
- /* Don't wait if LOCK_thd_data is used as this could cause a deadlock */
- if (!mysql_mutex_trylock(&thd->LOCK_thd_data))
- {
- if (thd->query())
- {
- if (max_query_len < 1)
- len= thd->query_length();
- else
- len= MY_MIN(thd->query_length(), max_query_len);
- str.append('\n');
- str.append(thd->query(), len);
- }
- mysql_mutex_unlock(&thd->LOCK_thd_data);
- }
- mysql_mutex_unlock(&LOCK_thread_count);
-
- if (str.c_ptr_safe() == buffer)
- return buffer;
-
- /*
- We have to copy the new string to the destination buffer because the string
- was reallocated to a larger buffer to be able to fit.
- */
- DBUG_ASSERT(buffer != NULL);
- length= MY_MIN(str.length(), length-1);
- memcpy(buffer, str.c_ptr_quick(), length);
- /* Make sure that the new string is null terminated */
- buffer[length]= '\0';
- return buffer;
-}
-
-
 #if MARIA_PLUGIN_INTERFACE_VERSION < 0x0200
 /**
  TODO: This function is for API compatibility, remove it eventually.

sql/sql_show.cc

@@ -9773,3 +9773,88 @@ static void get_cs_converted_string_value(THD *thd,
  return;
 }
 #endif
+
+/**
+ Dumps a text description of a thread, its security context
+ (user, host) and the current query.
+
+ @param thd thread context
+ @param buffer pointer to preferred result buffer
+ @param length length of buffer
+ @param max_query_len how many chars of query to copy (0 for all)
+
+ @return Pointer to string
+*/
+
+extern "C"
+char *thd_get_error_context_description(THD *thd, char *buffer,
+ unsigned int length,
+ unsigned int max_query_len)
+{
+ String str(buffer, length, &my_charset_latin1);
+ const Security_context *sctx= &thd->main_security_ctx;
+ char header[256];
+ int len;
+
+ mysql_mutex_lock(&LOCK_thread_count);
+
+ len= my_snprintf(header, sizeof(header),
+ "MySQL thread id %lu, OS thread handle 0x%lx, query id %lu",
+ thd->thread_id, (ulong) thd->real_id, (ulong) thd->query_id);
+ str.length(0);
+ str.append(header, len);
+
+ if (sctx->host)
+ {
+ str.append(' ');
+ str.append(sctx->host);
+ }
+
+ if (sctx->ip)
+ {
+ str.append(' ');
+ str.append(sctx->ip);
+ }
+
+ if (sctx->user)
+ {
+ str.append(' ');
+ str.append(sctx->user);
+ }
+
+ /* Don't wait if LOCK_thd_data is used as this could cause a deadlock */
+ if (!mysql_mutex_trylock(&thd->LOCK_thd_data))
+ {
+ if (const char *info= thread_state_info(thd))
+ {
+ str.append(' ');
+ str.append(info);
+ }
+
+ if (thd->query())
+ {
+ if (max_query_len < 1)
+ len= thd->query_length();
+ else
+ len= MY_MIN(thd->query_length(), max_query_len);
+ str.append('\n');
+ str.append(thd->query(), len);
+ }
+ mysql_mutex_unlock(&thd->LOCK_thd_data);
+ }
+ mysql_mutex_unlock(&LOCK_thread_count);
+
+ if (str.c_ptr_safe() == buffer)
+ return buffer;
+
+ /*
+ We have to copy the new string to the destination buffer because the string
+ was reallocated to a larger buffer to be able to fit.
+ */
+ DBUG_ASSERT(buffer != NULL);
+ length= MY_MIN(str.length(), length-1);
+ memcpy(buffer, str.c_ptr_quick(), length);
+ /* Make sure that the new string is null terminated */
+ buffer[length]= '\0';
+ return buffer;
+}