Skip to content

M
mariadb
Commit b9a7fe27 authored by unknown's avatar unknown
Browse files
Options

WL#3337 (Event scheduler new architecture) 

Cleaned up the code a bit. Fixed few leaks.
This code still does not load events on server startup
from disk. The problem is that there is a need for a THD instance, which
does not exist during server boot. This will be solved soon.
Still Event_timed is used both for the memory queue and for exectution.
This will be changed according to WL#3337 probably in the next commit.


sql/event_data_objects.cc:
  Strip unneeded stuff from class Event_timed
  Event_timed is still used for the queue and execution.
  That will be changed in the next commit.
sql/event_data_objects.h:
  Strip unneeded stuff from class Event_timed
  Event_timed is still used for the queue and execution.
  That will be changed in the next commit.
sql/event_db_repository.cc:
  Cosmetics.
  Add a new method load_named_event_job, to be made complete in the 
  next commit. It will load from disk an instance of Event_job_data to
  be used during execution.
sql/event_db_repository.h:
  find_event does not need MEM_ROOT anymore
  because the memory is allocated on Event's own root.
sql/event_queue.cc:
  Remove dead code.
  Move dumping of the queue to separate method.
  Make critical sections in create_event & update_event
  as small as possible - load the new event outside of the section
  and free the object also outside of it.
sql/event_queue.h:
  init -> init_queue -> easier for ctags
  deinit -> deinit_queue -> easier for ctags
sql/event_scheduler.cc:
  empty this file
sql/event_scheduler.h:
  empty this file
sql/event_scheduler_ng.cc:
  add back DBUG_RETURN(0) in thread handlers.
  We don't stop running events when stopping the scheduler. Therefore
  remove this method now. If it is needed later it can be added back.
sql/event_scheduler_ng.h:
  Remove stop_all_running_threads()
  init -> init_scheduler
  deinit -> deinit_scheduler
  easier for ctags
sql/events.cc:
  Cosmetics
sql/events.h:
  Cosmetics
sql/set_var.cc:
  Remove references to dead code
sql/sql_parse.cc:
  Reorganize a bit.
parent a5dfeb02
Show whitespace changes
Inline Side-by-side
Showing with 243 additions and 2287 deletions
sql/event_data_objects.cc
View file @ b9a7fe27
......@@ -530,18 +530,14 @@ Event_parse_data::init_ends(THD *thd, Item *new_ends)
Event_timed::Event_timed()
*/
Event_timed::Event_timed():in_spawned_thread(0),locked_by_thread_id(0),
running(0), thread_id(0), status_changed(false),
Event_timed::Event_timed():status_changed(false),
last_executed_changed(false), expression(0),
created(0), modified(0),
on_completion(Event_timed::ON_COMPLETION_DROP),
status(Event_timed::ENABLED), sphead(0),
sql_mode(0), dropped(false),
free_sphead_on_delete(true), flags(0)
sql_mode(0), dropped(false), flags(0)
{
pthread_mutex_init(&this->LOCK_running, MY_MUTEX_INIT_FAST);
pthread_cond_init(&this->COND_finished, NULL);
init();
}
......@@ -555,49 +551,11 @@ Event_timed::Event_timed():in_spawned_thread(0),locked_by_thread_id(0),
Event_timed::~Event_timed()
{
deinit_mutexes();
free_root(&mem_root, MYF(0));
if (free_sphead_on_delete)
free_sp();
}
/*
Destructor
SYNOPSIS
Event_timed::deinit_mutexes()
*/
void
Event_timed::deinit_mutexes()
{
pthread_mutex_destroy(&this->LOCK_running);
pthread_cond_destroy(&this->COND_finished);
}
/*
Checks whether the event is running
SYNOPSIS
Event_timed::is_running()
*/
bool
Event_timed::is_running()
{
bool ret;
VOID(pthread_mutex_lock(&this->LOCK_running));
ret= running;
VOID(pthread_mutex_unlock(&this->LOCK_running));
return ret;
}
/*
Init all member variables
......@@ -1253,7 +1211,7 @@ Event_timed::update_fields(THD *thd)
Open_tables_state backup;
int ret;
DBUG_ENTER("Event_timed::update_time_fields");
DBUG_ENTER("Event_timed::update_fields");
DBUG_PRINT("enter", ("name: %*s", name.length, name.str));
......@@ -1382,7 +1340,7 @@ Event_timed::get_create_event(THD *thd, String *buf)
Executes the event (the underlying sp_head object);
SYNOPSIS
evex_fill_row()
Event_timed::execute()
thd THD
mem_root If != NULL use it to compile the event on it
......@@ -1607,149 +1565,6 @@ done:
}
extern pthread_attr_t connection_attrib;
/*
Checks whether is possible and forks a thread. Passes self as argument.
RETURN VALUE
EVENT_EXEC_STARTED OK
EVENT_EXEC_ALREADY_EXEC Thread not forked, already working
EVENT_EXEC_CANT_FORK Unable to spawn thread (error)
*/
int
Event_timed::spawn_now(void * (*thread_func)(void*), void *arg)
{
THD *thd= current_thd;
int ret= EVENT_EXEC_STARTED;
DBUG_ENTER("Event_timed::spawn_now");
DBUG_PRINT("info", ("[%s.%s]", dbname.str, name.str));
VOID(pthread_mutex_lock(&this->LOCK_running));
DBUG_PRINT("info", ("SCHEDULER: execute_at of %s is %lld", name.str,
TIME_to_ulonglong_datetime(&execute_at)));
mark_last_executed(thd);
if (compute_next_execution_time())
{
sql_print_error("SCHEDULER: Error while computing time of %s.%s . "
"Disabling after execution.", dbname.str, name.str);
status= DISABLED;
}
DBUG_PRINT("evex manager", ("[%10s] next exec at [%llu]", name.str,
TIME_to_ulonglong_datetime(&execute_at)));
/*
1. For one-time event : year is > 0 and expression is 0
2. For recurring, expression is != -=> check execute_at_null in this case
*/
if ((execute_at.year && !expression) || execute_at_null)
{
sql_print_information("SCHEDULER: [%s.%s of %s] no more executions "
"after this one", dbname.str, name.str,
definer.str);
flags |= EVENT_EXEC_NO_MORE | EVENT_FREE_WHEN_FINISHED;
}
update_fields(thd);
if (!in_spawned_thread)
{
pthread_t th;
in_spawned_thread= true;
if (pthread_create(&th, &connection_attrib, thread_func, arg))
{
DBUG_PRINT("info", ("problem while spawning thread"));
ret= EVENT_EXEC_CANT_FORK;
in_spawned_thread= false;
}
}
else
{
DBUG_PRINT("info", ("already in spawned thread. skipping"));
ret= EVENT_EXEC_ALREADY_EXEC;
}
VOID(pthread_mutex_unlock(&this->LOCK_running));
DBUG_RETURN(ret);
}
bool
Event_timed::spawn_thread_finish(THD *thd)
{
bool should_free;
DBUG_ENTER("Event_timed::spawn_thread_finish");
VOID(pthread_mutex_lock(&LOCK_running));
in_spawned_thread= false;
DBUG_PRINT("info", ("Sending COND_finished for thread %d", thread_id));
thread_id= 0;
if (dropped)
drop(thd);
pthread_cond_broadcast(&COND_finished);
should_free= flags & EVENT_FREE_WHEN_FINISHED;
VOID(pthread_mutex_unlock(&LOCK_running));
DBUG_RETURN(should_free);
}
/*
Kills a running event
SYNOPSIS
Event_timed::kill_thread()
RETURN VALUE
0 OK
-1 EVEX_CANT_KILL
!0 Error
*/
int
Event_timed::kill_thread(THD *thd)
{
int ret= 0;
DBUG_ENTER("Event_timed::kill_thread");
pthread_mutex_lock(&LOCK_running);
DBUG_PRINT("info", ("thread_id=%lu", thread_id));
if (thread_id == thd->thread_id)
{
/*
We don't kill ourselves in cases like :
alter event e_43 do alter event e_43 do set @a = 4 because
we will never receive COND_finished.
*/
DBUG_PRINT("info", ("It's not safe to kill ourselves in self altering queries"));
ret= EVEX_CANT_KILL;
}
else if (thread_id && !(ret= kill_one_thread(thd, thread_id, false)))
{
thd->enter_cond(&COND_finished, &LOCK_running, "Waiting for finished");
DBUG_PRINT("info", ("Waiting for COND_finished from thread %d", thread_id));
while (thread_id)
pthread_cond_wait(&COND_finished, &LOCK_running);
DBUG_PRINT("info", ("Got COND_finished"));
/* This will implicitly unlock LOCK_running. Hence we return before that */
thd->exit_cond("");
DBUG_RETURN(0);
}
else if (!thread_id && in_spawned_thread)
{
/*
Because the manager thread waits for the forked thread to update thread_id
this situation is impossible.
*/
DBUG_ASSERT(0);
}
pthread_mutex_unlock(&LOCK_running);
DBUG_PRINT("exit", ("%d", ret));
DBUG_RETURN(ret);
}
/*
Checks whether two events have the same name
......
sql/event_data_objects.h
View file @ b9a7fe27
......@@ -63,12 +63,6 @@ class Event_timed
{
Event_timed(const Event_timed &); /* Prevent use of these */
void operator=(Event_timed &);
my_bool in_spawned_thread;
ulong locked_by_thread_id;
my_bool running;
ulong thread_id;
pthread_mutex_t LOCK_running;
pthread_cond_t COND_finished;
bool status_changed;
bool last_executed_changed;
......@@ -118,7 +112,6 @@ public:
ulong sql_mode;
bool dropped;
bool free_sphead_on_delete;
uint flags;//all kind of purposes
static void *operator new(size_t size)
......@@ -146,9 +139,6 @@ public:
void
init();
void
deinit_mutexes();
int
load_from_row(TABLE *table);
......@@ -173,23 +163,8 @@ public:
int
compile(THD *thd, MEM_ROOT *mem_root);
bool
is_running();
int
spawn_now(void * (*thread_func)(void*), void *arg);
bool
spawn_thread_finish(THD *thd);
void
free_sp();
int
kill_thread(THD *thd);
void
set_thread_id(ulong tid) { thread_id= tid; }
};
......
sql/event_db_repository.cc
View file @ b9a7fe27
......@@ -374,8 +374,7 @@ Event_db_repository::table_scan_all_for_i_s(THD *thd, TABLE *schema_table,
ret= read_record_info.read_record(&read_record_info);
if (ret == 0)
ret= copy_event_to_schema_table(thd, schema_table, event_table);
}
while (ret == 0);
} while (ret == 0);
DBUG_PRINT("info", ("Scan finished. ret=%d", ret));
end_read_record(&read_record_info);
......@@ -464,8 +463,7 @@ Event_db_repository::fill_schema_events(THD *thd, TABLE_LIST *tables, char *db)
int
Event_db_repository::find_event(THD *thd, LEX_STRING dbname, LEX_STRING name,
Event_timed **ett,
TABLE *tbl, MEM_ROOT *root)
Event_timed **ett, TABLE *tbl)
{
TABLE *table;
int ret;
......@@ -505,7 +503,7 @@ done:
if (ret)
{
delete et;
et= 0;
et= NULL;
}
/* don't close the table if we haven't opened it ourselves */
if (!tbl && table)
......@@ -518,7 +516,6 @@ done:
int
Event_db_repository::init_repository()
{
init_alloc_root(&repo_root, MEM_ROOT_BLOCK_SIZE, MEM_ROOT_PREALLOC);
return 0;
}
......@@ -526,7 +523,6 @@ Event_db_repository::init_repository()
void
Event_db_repository::deinit_repository()
{
free_root(&repo_root, MYF(0));
}
......@@ -731,7 +727,8 @@ Event_db_repository::create_event(THD *thd, Event_parse_data *parse_data,
parse_data->name.str));
DBUG_PRINT("info", ("check existance of an event with the same name"));
if (!evex_db_find_event_by_name(thd, parse_data->dbname, parse_data->name, table))
if (!evex_db_find_event_by_name(thd, parse_data->dbname,
parse_data->name, table))
{
if (create_if_not)
{
......@@ -1026,14 +1023,12 @@ Event_db_repository::find_event_by_name(THD *thd, LEX_STRING db,
*/
if (db.length > table->field[ET_FIELD_DB]->field_length ||
name.length > table->field[ET_FIELD_NAME]->field_length)
DBUG_RETURN(EVEX_KEY_NOT_FOUND);
table->field[ET_FIELD_DB]->store(db.str, db.length, &my_charset_bin);
table->field[ET_FIELD_NAME]->store(name.str, name.length, &my_charset_bin);
key_copy(key, table->record[0], table->key_info,
table->key_info->key_length);
key_copy(key, table->record[0], table->key_info, table->key_info->key_length);
if (table->file->index_read_idx(table->record[0], 0, key,
table->key_info->key_length,
......@@ -1125,7 +1120,7 @@ Event_db_repository::drop_events_by_field(THD *thd,
the table, compiles and inserts it into the cache.
SYNOPSIS
Event_scheduler::load_named_event()
Event_db_repository::load_named_event_timed()
thd THD
etn The name of the event to load and compile on scheduler's root
etn_new The loaded event
......@@ -1136,7 +1131,8 @@ Event_db_repository::drop_events_by_field(THD *thd,
*/
int
Event_db_repository::load_named_event(THD *thd, LEX_STRING dbname, LEX_STRING name,
Event_db_repository::load_named_event_timed(THD *thd, LEX_STRING dbname,
LEX_STRING name,
Event_timed **etn_new)
{
int ret= 0;
......@@ -1144,12 +1140,12 @@ Event_db_repository::load_named_event(THD *thd, LEX_STRING dbname, LEX_STRING na
Event_timed *et_loaded= NULL;
Open_tables_state backup;
DBUG_ENTER("Event_db_repository::load_named_event");
DBUG_ENTER("Event_db_repository::load_named_event_timed");
DBUG_PRINT("enter",("thd=%p name:%*s",thd, name.length, name.str));
thd->reset_n_backup_open_tables_state(&backup);
/* No need to use my_error() here because db_find_event() has done it */
ret= find_event(thd, dbname, name, &et_loaded, NULL, &repo_root);
ret= find_event(thd, dbname, name, &et_loaded, NULL);
thd->restore_backup_open_tables_state(&backup);
/* In this case no memory was allocated so we don't need to clean */
if (ret)
......@@ -1171,3 +1167,57 @@ Event_db_repository::load_named_event(THD *thd, LEX_STRING dbname, LEX_STRING na
DBUG_RETURN(OP_OK);
}
/*
Looks for a named event in mysql.event and then loads it from
the table, compiles and inserts it into the cache.
SYNOPSIS
Event_db_repository::load_named_event_job()
thd THD
etn The name of the event to load and compile on scheduler's root
etn_new The loaded event
RETURN VALUE
NULL Error during compile or the event is non-enabled.
otherwise Address
*/
int
Event_db_repository::load_named_event_job(THD *thd, LEX_STRING dbname,
LEX_STRING name,
Event_job_data **etn_new)
{
int ret= 0;
MEM_ROOT *tmp_mem_root;
Event_timed *et_loaded= NULL;
Open_tables_state backup;
DBUG_ENTER("Event_db_repository::load_named_event_job");
DBUG_PRINT("enter",("thd=%p name:%*s",thd, name.length, name.str));
#if 0
thd->reset_n_backup_open_tables_state(&backup);
/* No need to use my_error() here because db_find_event() has done it */
ret= find_event(thd, dbname, name, &et_loaded, NULL);
thd->restore_backup_open_tables_state(&backup);
/* In this case no memory was allocated so we don't need to clean */
if (ret)
DBUG_RETURN(OP_LOAD_ERROR);
if (et_loaded->status != Event_timed::ENABLED)
{
/*
We don't load non-enabled events.
In db_find_event() `et_new` was allocated on the heap and not on
scheduler_root therefore we delete it here.
*/
delete et_loaded;
DBUG_RETURN(OP_DISABLED_EVENT);
}
et_loaded->compute_next_execution_time();
*etn_new= et_loaded;
#endif
DBUG_RETURN(OP_OK);
}
sql/event_db_repository.h
View file @ b9a7fe27
......@@ -56,6 +56,7 @@ fill_schema_events(THD *thd, TABLE_LIST *tables, COND * /* cond */);
class Event_timed;
class Event_parse_data;
class Event_queue_element;
class Event_job_data;
class Event_db_repository
{
......@@ -88,10 +89,15 @@ public:
int
find_event(THD *thd, LEX_STRING dbname, LEX_STRING name, Event_timed **ett,
TABLE *tbl, MEM_ROOT *root);
TABLE *tbl);
int
load_named_event(THD *thd, LEX_STRING dbname, LEX_STRING name, Event_timed **etn_new);
load_named_event_timed(THD *thd, LEX_STRING dbname, LEX_STRING name,
Event_timed **etn_new);
int
load_named_event_job(THD *thd, LEX_STRING dbname, LEX_STRING name,
Event_job_data **etn_new);
int
find_event_by_name(THD *thd, LEX_STRING db, LEX_STRING name, TABLE *table);
......@@ -116,8 +122,6 @@ private:
static bool
check_system_tables(THD *thd);
MEM_ROOT repo_root;
/* Prevent use of these */
Event_db_repository(const Event_db_repository &);
void operator=(Event_db_repository &);
......
sql/event_queue.cc
View file @ b9a7fe27
......@@ -90,34 +90,29 @@ Event_queue::Event_queue()
RETURN VALUE
OP_OK OK or scheduler not working
OP_LOAD_ERROR Error during loading from disk
OP_ALREADY_EXISTS Event already in the queue
*/
int
Event_queue::create_event(THD *thd, Event_parse_data *et, bool check_existence)
Event_queue::create_event(THD *thd, Event_parse_data *et)
{
int res;
Event_timed *et_new;
DBUG_ENTER("Event_queue::create_event");
DBUG_PRINT("enter", ("thd=%p et=%p lock=%p",thd,et, &LOCK_event_queue));
res= db_repository->load_named_event_timed(thd, et->dbname, et->name, &et_new);
LOCK_QUEUE_DATA();
if (check_existence && find_event(et->dbname, et->name, FALSE))
{
res= OP_ALREADY_EXISTS;
goto end;
}
if (!(res= db_repository->
load_named_event(thd, et->dbname, et->name, &et_new)))
if (!res)
{
DBUG_PRINT("info", ("new event in the queue %p", et_new));
queue_insert_safe(&queue, (byte *) et_new);
on_queue_change();
notify_observers();
}
else if (res == OP_DISABLED_EVENT)
res= OP_OK;
end:
UNLOCK_QUEUE_DATA();
DBUG_RETURN(res);
}
......@@ -129,104 +124,54 @@ end:
Event_queue::update_event()
thd Thread
et The event to replace(add) into the queue
new_schema New schema
new_name New name
new_schema New schema, in case of RENAME TO
new_name New name, in case of RENAME TO
RETURN VALUE
OP_OK OK or scheduler not working
OP_LOAD_ERROR Error during loading from disk
OP_ALREADY_EXISTS Event already in the queue
*/
int
Event_queue::update_event(THD *thd, Event_parse_data *et,
LEX_STRING *new_schema,
LEX_STRING *new_name)
LEX_STRING *new_schema, LEX_STRING *new_name)
{
int res= OP_OK;
Event_timed *et_old, *et_new= NULL;
LEX_STRING old_schema, old_name;
LINT_INIT(old_schema.str);
LINT_INIT(old_schema.length);
LINT_INIT(old_name.str);
LINT_INIT(old_name.length);
int res;
Event_timed *et_old= NULL, *et_new= NULL;
DBUG_ENTER("Event_queue::update_event");
DBUG_PRINT("enter", ("thd=%p et=%p et=[%s.%s] lock=%p",
thd, et, et->dbname.str, et->name.str, &LOCK_event_queue));
res= db_repository->
load_named_event_timed(thd, new_schema?*new_schema:et->dbname,
new_name? *new_name:et->name, &et_new);
if (res && res != OP_DISABLED_EVENT)
goto end;
LOCK_QUEUE_DATA();
if (!(et_old= find_event(et->dbname, et->name, TRUE)))
{
DBUG_PRINT("info", ("%s.%s not found cached, probably was DISABLED",
et->dbname.str, et->name.str));
if (new_schema && new_name)
{
old_schema= et->dbname;
old_name= et->name;
et->dbname= *new_schema;
et->name= *new_name;
}
if (!(res= db_repository->
load_named_event(thd, et->dbname, et->name, &et_new)))
if (!res)
{
DBUG_PRINT("info", ("new event in the queue %p old %p", et_new, et_old));
queue_insert_safe(&queue, (byte *) et_new);
on_queue_change();
}
else if (res == OP_DISABLED_EVENT)
res= OP_OK;
if (new_schema && new_name)
{
et->dbname= old_schema;
et->name= old_name;
}
DBUG_PRINT("info", ("res=%d", res));
UNLOCK_QUEUE_DATA();
/*
Andrey: Is this comment still truthful ???
We don't move this code above because a potential kill_thread will call
THD::awake(). Which in turn will try to acqure mysys_var->current_mutex,
which is LOCK_event_queue on which the COND_new_work in ::run() locks.
Hence, we try to acquire a lock which we have already acquired and we run
into an assert. Holding LOCK_event_queue however is not needed because
we don't touch any invariant of the scheduler anymore. ::drop_event() does
the same.
*/
notify_observers();
if (et_old)
{
switch (et_old->kill_thread(thd)) {
case EVEX_CANT_KILL:
/* Don't delete but continue */
et_old->flags |= EVENT_FREE_WHEN_FINISHED;
break;
case 0:
/*
kill_thread() waits till the spawned thread finishes after it's
killed. Hence, we delete here memory which is no more referenced from
a running thread.
*/
delete et_old;
/*
We don't signal COND_new_work here because:
1. Even if the dropped event is on top of the queue this will not
move another one to be executed before the time the one on the
top (but could be at the same second as the dropped one)
2. If this was the last event on the queue, then pthread_cond_timedwait
in ::run() will finish and then see that the queue is empty and
call cond_wait(). Hence, no need to interrupt the blocked
::run() thread.
*/
break;
default:
DBUG_ASSERT(0);
}
}
end:
DBUG_PRINT("info", ("res=%d", res));
DBUG_RETURN(res);
}
......@@ -256,40 +201,13 @@ Event_queue::drop_event(THD *thd, sp_name *name)
LOCK_QUEUE_DATA();
if (!(et_old= find_event(name->m_db, name->m_name, TRUE)))
DBUG_PRINT("info", ("No such event found, probably DISABLED"));
UNLOCK_QUEUE_DATA();
/* See comments in ::replace_event() why this is split in two parts. */
if (et_old)
{
switch ((res= et_old->kill_thread(thd))) {
case EVEX_CANT_KILL:
/* Don't delete but continue */
et_old->flags |= EVENT_FREE_WHEN_FINISHED;
break;
case 0:
/*
kill_thread() waits till the spawned thread finishes after it's
killed. Hence, we delete here memory which is no more referenced from
a running thread.
*/
delete et_old;
/*
We don't signal COND_new_work here because:
1. Even if the dropped event is on top of the queue this will not
move another one to be executed before the time the one on the
top (but could be at the same second as the dropped one)
2. If this was the last event on the queue, then pthread_cond_timedwait
in ::run() will finish and then see that the queue is empty and
call cond_wait(). Hence, no need to interrupt the blocked
::run() thread.
We don't signal here because the scheduler will catch the change
next time it wakes up.
*/
break;
default:
sql_print_error("SCHEDULER: Got unexpected error %d", res);
DBUG_ASSERT(0);
}
}
DBUG_RETURN(FALSE);
}
......@@ -361,7 +279,7 @@ Event_queue::drop_matching_events(THD *thd, LEX_STRING pattern,
DBUG_ENTER("Event_queue::drop_matching_events");
DBUG_PRINT("enter", ("pattern=%*s state=%d", pattern.length, pattern.str));
uint i= 0, dropped= 0;
uint i= 0;
while (i < queue.elements)
{
Event_timed *et= (Event_timed *) queue_element(&queue, i);
......@@ -375,30 +293,20 @@ Event_queue::drop_matching_events(THD *thd, LEX_STRING pattern,
counter and the (i < queue.elements) condition is ok.
*/
queue_remove(&queue, i);
/* See replace_event() */
switch (et->kill_thread(thd)) {
case EVEX_CANT_KILL:
/* Don't delete but continue */
et->flags |= EVENT_FREE_WHEN_FINISHED;
++dropped;
break;
case 0:
delete et;
++dropped;
break;
default:
DBUG_ASSERT(0);
}
}
else
i++;
}
DBUG_PRINT("info", ("Dropped %lu", dropped));
/*
Don't send COND_new_work because no need to wake up the scheduler thread.
When it wakes next time up it will recalculate how much more it should
sleep if the top of the queue has been changed by this method.
We don't call notify_observers() . If we remove the top event:
1. The queue is empty. The scheduler will wake up at some time and realize
that the queue is empty. If create_event() comes inbetween it will
signal the scheduler
2. The queue is not empty, but the next event after the previous top, won't
be executed any time sooner than the element we removed. Hence, we may
not notify the scheduler and it will realize the change when it
wakes up from timedwait.
*/
DBUG_VOID_RETURN;
......@@ -418,16 +326,14 @@ Event_queue::drop_matching_events(THD *thd, LEX_STRING pattern,
>=0 Number of dropped events
*/
int
void
Event_queue::drop_schema_events(THD *thd, LEX_STRING schema)
{
int ret;
DBUG_ENTER("Event_queue::drop_schema_events");
LOCK_QUEUE_DATA();
drop_matching_events(thd, schema, event_timed_db_equal);
UNLOCK_QUEUE_DATA();
DBUG_RETURN(ret);
DBUG_VOID_RETURN;
}
......@@ -744,13 +650,13 @@ Event_queue::deinit_mutexes()
its state.
SYNOPSIS
Event_queue::on_queue_change()
Event_queue::notify_observers()
*/
void
Event_queue::on_queue_change()
Event_queue::notify_observers()
{
DBUG_ENTER("Event_queue::on_queue_change");
DBUG_ENTER("Event_queue::notify_observers");
DBUG_PRINT("info", ("Signalling change of the queue"));
scheduler->queue_changed();
DBUG_VOID_RETURN;
......@@ -761,7 +667,7 @@ Event_queue::on_queue_change()
The implementation of full-fledged initialization.
SYNOPSIS
Event_scheduler::init()
Event_queue::init()
RETURN VALUE
FALSE OK
......@@ -769,15 +675,16 @@ Event_queue::on_queue_change()
*/
bool
Event_queue::init(Event_db_repository *db_repo)
Event_queue::init_queue(Event_db_repository *db_repo, Event_scheduler_ng *sched)
{
int i= 0;
bool ret= FALSE;
DBUG_ENTER("Event_queue::init");
DBUG_ENTER("Event_queue::init_queue");
DBUG_PRINT("enter", ("this=%p", this));
LOCK_QUEUE_DATA();
db_repository= db_repo;
scheduler= sched;
if (init_queue_ex(&queue, 30 /*num_el*/, 0 /*offset*/, 0 /*smallest_on_top*/,
event_timed_compare_q, NULL, 30 /*auto_extent*/))
......@@ -803,9 +710,9 @@ end:
void
Event_queue::deinit()
Event_queue::deinit_queue()
{
DBUG_ENTER("Event_queue::deinit");
DBUG_ENTER("Event_queue::deinit_queue");
LOCK_QUEUE_DATA();
empty_queue();
......@@ -833,6 +740,8 @@ void
Event_queue::empty_queue()
{
uint i;
DBUG_ENTER("Event_queue::empty_queue");
DBUG_PRINT("enter", ("Purging the queue. %d element(s)", queue.elements));
/* empty the queue */
for (i= 0; i < events_count_no_lock(); ++i)
{
......@@ -840,6 +749,7 @@ Event_queue::empty_queue()
delete et;
}
resize_queue(&queue, 0);
DBUG_VOID_RETURN;
}
......@@ -864,6 +774,29 @@ Event_queue::top_changed()
}
inline void
Event_queue::dbug_dump_queue(time_t now)
{
#ifndef DBUG_OFF
Event_timed *et;
uint i;
DBUG_PRINT("info", ("Dumping queue . Elements=%u", queue.elements));
for (i = 0; i < queue.elements; i++)
{
et= ((Event_timed*)queue_element(&queue, i));
DBUG_PRINT("info",("et=%p db=%s name=%s",et, et->dbname.str, et->name.str));
DBUG_PRINT("info", ("exec_at=%llu starts=%llu ends=%llu "
" expr=%lld et.exec_at=%d now=%d (et.exec_at - now)=%d if=%d",
TIME_to_ulonglong_datetime(&et->execute_at),
TIME_to_ulonglong_datetime(&et->starts),
TIME_to_ulonglong_datetime(&et->ends),
et->expression, sec_since_epoch_TIME(&et->execute_at), now,
(int)(sec_since_epoch_TIME(&et->execute_at) - now),
sec_since_epoch_TIME(&et->execute_at) <= now));
}
#endif
}
Event_timed *
Event_queue::get_top_for_execution_if_time(THD *thd, time_t now,
struct timespec *abstime)
......@@ -876,35 +809,21 @@ Event_queue::get_top_for_execution_if_time(THD *thd, time_t now,
LOCK_QUEUE_DATA();
do {
int res;
Event_timed *et= NULL;
if (!queue.elements)
{
abstime->tv_sec= 0;
break;
}
int i;
DBUG_PRINT("info", ("Dumping queue . Elements=%u", queue.elements));
for (i = 0; i < queue.elements; i++)
{
et= ((Event_timed*)queue_element(&queue, i));
DBUG_PRINT("info",("et=%p db=%s name=%s",et, et->dbname.str, et->name.str));
DBUG_PRINT("info", ("exec_at=%llu starts=%llu ends=%llu "
" expr=%lld et.exec_at=%d now=%d (et.exec_at - now)=%d if=%d",
TIME_to_ulonglong_datetime(&et->execute_at),
TIME_to_ulonglong_datetime(&et->starts),
TIME_to_ulonglong_datetime(&et->ends),
et->expression, sec_since_epoch_TIME(&et->execute_at), now,
(int)(sec_since_epoch_TIME(&et->execute_at) - now),
sec_since_epoch_TIME(&et->execute_at) <= now));
}
et= ((Event_timed*)queue_element(&queue, 0));
dbug_dump_queue(now);
Event_timed *et= ((Event_timed*)queue_element(&queue, 0));
top_time.tv_sec= sec_since_epoch_TIME(&et->execute_at);
if (top_time.tv_sec <= now)
{
DBUG_PRINT("info", ("Ready for execution"));
abstime->tv_sec= 0;
if ((res= db_repository->load_named_event(thd, et->dbname, et->name,
if ((res= db_repository->load_named_event_timed(thd, et->dbname, et->name,
&et_new)))
{
DBUG_ASSERT(0);
......
sql/event_queue.h
View file @ b9a7fe27
......@@ -38,15 +38,15 @@ public:
deinit_mutexes();
bool
init(Event_db_repository *db_repo);
init_queue(Event_db_repository *db_repo, Event_scheduler_ng *sched);
void
deinit();
deinit_queue();
/* Methods for queue management follow */
int
create_event(THD *thd, Event_parse_data *et, bool check_existence);
create_event(THD *thd, Event_parse_data *et);
int
update_event(THD *thd, Event_parse_data *et, LEX_STRING *new_schema,
......@@ -55,13 +55,9 @@ public:
bool
drop_event(THD *thd, sp_name *name);
int
void
drop_schema_events(THD *thd, LEX_STRING schema);
int
drop_user_events(THD *thd, LEX_STRING *definer)
{ DBUG_ASSERT(0); return 0;}
uint
events_count();
......@@ -89,7 +85,7 @@ public:
void
top_changed();
///////////////protected
protected:
Event_timed *
find_event(LEX_STRING db, LEX_STRING name, bool remove_from_q);
......@@ -105,8 +101,6 @@ public:
Event_db_repository *db_repository;
/* The sorted queue with the Event_timed objects */
QUEUE queue;
uint mutex_last_locked_at_line;
uint mutex_last_unlocked_at_line;
......@@ -122,10 +116,16 @@ public:
unlock_data(const char *func, uint line);
void
on_queue_change();
notify_observers();
void
dbug_dump_queue(time_t now);
Event_scheduler_ng *scheduler;
protected:
//public:
/* The sorted queue with the Event_timed objects */
QUEUE queue;
};
......
sql/event_scheduler.cc
View file @ b9a7fe27
......@@ -14,1540 +14,3 @@
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
#include "mysql_priv.h"
#include "events.h"
#include "event_data_objects.h"
#include "event_scheduler.h"
#include "event_db_repository.h"
#include "sp_head.h"
#include "event_queue.h"
#ifdef __GNUC__
#if __GNUC__ >= 2
#define SCHED_FUNC __FUNCTION__
#endif
#else
#define SCHED_FUNC "<unknown>"
#endif
#define LOCK_SCHEDULER_DATA() lock_data(SCHED_FUNC, __LINE__)
#define UNLOCK_SCHEDULER_DATA() unlock_data(SCHED_FUNC, __LINE__)
Event_scheduler*
Event_scheduler::singleton= NULL;
#ifndef DBUG_OFF
static
LEX_STRING states_names[] =
{
{(char*) STRING_WITH_LEN("UNINITIALIZED")},
{(char*) STRING_WITH_LEN("INITIALIZED")},
{(char*) STRING_WITH_LEN("COMMENCING")},
{(char*) STRING_WITH_LEN("CANTSTART")},
{(char*) STRING_WITH_LEN("RUNNING")},
{(char*) STRING_WITH_LEN("SUSPENDED")},
{(char*) STRING_WITH_LEN("IN_SHUTDOWN")}
};
#endif
const char * const
Event_scheduler::cond_vars_names[Event_scheduler::COND_LAST] =
{
"new work",
"started or stopped",
"suspend or resume"
};
/*
Event_scheduler*
Event_scheduler::singleton= NULL;
*/
class Worker_thread_param
{
public:
Event_timed *et;
pthread_mutex_t LOCK_started;
pthread_cond_t COND_started;
bool started;
Worker_thread_param(Event_timed *etn):et(etn), started(FALSE)
{
pthread_mutex_init(&LOCK_started, MY_MUTEX_INIT_FAST);
pthread_cond_init(&COND_started, NULL);
}
~Worker_thread_param()
{
pthread_mutex_destroy(&LOCK_started);
pthread_cond_destroy(&COND_started);
}
};
/*
Prints the stack of infos, warnings, errors from thd to
the console so it can be fetched by the logs-into-tables and
checked later.
SYNOPSIS
evex_print_warnings
thd - thread used during the execution of the event
et - the event itself
*/
static void
evex_print_warnings(THD *thd, Event_timed *et)
{
MYSQL_ERROR *err;
DBUG_ENTER("evex_print_warnings");
if (!thd->warn_list.elements)
DBUG_VOID_RETURN;
char msg_buf[10 * STRING_BUFFER_USUAL_SIZE];
char prefix_buf[5 * STRING_BUFFER_USUAL_SIZE];
String prefix(prefix_buf, sizeof(prefix_buf), system_charset_info);
prefix.length(0);
prefix.append("SCHEDULER: [");
append_identifier(thd, &prefix, et->definer_user.str, et->definer_user.length);
prefix.append('@');
append_identifier(thd, &prefix, et->definer_host.str, et->definer_host.length);
prefix.append("][", 2);
append_identifier(thd,&prefix, et->dbname.str, et->dbname.length);
prefix.append('.');
append_identifier(thd,&prefix, et->name.str, et->name.length);
prefix.append("] ", 2);
List_iterator_fast<MYSQL_ERROR> it(thd->warn_list);
while ((err= it++))
{
String err_msg(msg_buf, sizeof(msg_buf), system_charset_info);
/* set it to 0 or we start adding at the end. That's the trick ;) */
err_msg.length(0);
err_msg.append(prefix);
err_msg.append(err->msg, strlen(err->msg), system_charset_info);
err_msg.append("]");
DBUG_ASSERT(err->level < 3);
(sql_print_message_handlers[err->level])("%*s", err_msg.length(),
err_msg.c_ptr());
}
DBUG_VOID_RETURN;
}
/*
Inits an scheduler thread handler, both the main and a worker
SYNOPSIS
init_event_thread()
thd - the THD of the thread. Has to be allocated by the caller.
NOTES
1. The host of the thead is my_localhost
2. thd->net is initted with NULL - no communication.
RETURN VALUE
0 OK
-1 Error
*/
static int
init_event_thread(THD** t, enum enum_thread_type thread_type)
{
THD *thd= *t;
thd->thread_stack= (char*)t; // remember where our stack is
DBUG_ENTER("init_event_thread");
thd->client_capabilities= 0;
thd->security_ctx->master_access= 0;
thd->security_ctx->db_access= 0;
thd->security_ctx->host_or_ip= (char*)my_localhost;
my_net_init(&thd->net, 0);
thd->net.read_timeout= slave_net_timeout;
thd->slave_thread= 0;
thd->options|= OPTION_AUTO_IS_NULL;
thd->client_capabilities|= CLIENT_MULTI_RESULTS;
thd->real_id=pthread_self();
VOID(pthread_mutex_lock(&LOCK_thread_count));
thd->thread_id= thread_id++;
threads.append(thd);
thread_count++;
thread_running++;
VOID(pthread_mutex_unlock(&LOCK_thread_count));
if (init_thr_lock() || thd->store_globals())
{
thd->cleanup();
DBUG_RETURN(-1);
}
#if !defined(__WIN__) && !defined(OS2) && !defined(__NETWARE__)
sigset_t set;
VOID(sigemptyset(&set)); // Get mask in use
VOID(pthread_sigmask(SIG_UNBLOCK,&set,&thd->block_signals));
#endif
/*
Guarantees that we will see the thread in SHOW PROCESSLIST though its
vio is NULL.
*/
thd->system_thread= thread_type;
thd->proc_info= "Initialized";
thd->version= refresh_version;
thd->set_time();
DBUG_RETURN(0);
}
/*
Inits the main scheduler thread and then calls Event_scheduler::run()
of arg.
SYNOPSIS
event_scheduler_thread()
arg void* ptr to Event_scheduler
NOTES
1. The host of the thead is my_localhost
2. thd->net is initted with NULL - no communication.
3. The reason to have a proxy function is that it's not possible to
use a method as function to be executed in a spawned thread:
- our pthread_hander_t macro uses extern "C"
- separating thread setup from the real execution loop is also to be
considered good.
RETURN VALUE
0 OK
*/
pthread_handler_t
event_scheduler_thread(void *arg)
{
/* needs to be first for thread_stack */
THD *thd= NULL;
Event_scheduler *scheduler= (Event_scheduler *) arg;
DBUG_ENTER("event_scheduler_thread");
my_thread_init();
pthread_detach_this_thread();
/* note that constructor of THD uses DBUG_ ! */
if (!(thd= new THD) || init_event_thread(&thd, SYSTEM_THREAD_EVENT_SCHEDULER))
{
sql_print_error("SCHEDULER: Cannot init manager event thread.");
scheduler->report_error_during_start();
}
else
{
thd->security_ctx->set_user((char*)"event_scheduler");
sql_print_information("SCHEDULER: Manager thread booting");
if (Event_scheduler::get_instance()->event_queue->check_system_tables(thd))
scheduler->report_error_during_start();
else
scheduler->run(thd);
/*
NOTE: Don't touch `scheduler` after this point because we have notified
the
thread which shuts us down that we have finished cleaning. In this
very moment a new scheduler thread could be started and a crash is
not welcome.
*/
}
/*
If we cannot create THD then don't decrease because we haven't touched
thread_count and thread_running in init_event_thread() which was never
called. In init_event_thread() thread_count and thread_running are
always increased even in the case the method returns an error.
*/
if (thd)
{
thd->proc_info= "Clearing";
DBUG_ASSERT(thd->net.buff != 0);
net_end(&thd->net);
pthread_mutex_lock(&LOCK_thread_count);
thread_count--;
thread_running--;
delete thd;
pthread_mutex_unlock(&LOCK_thread_count);
}
my_thread_end();
DBUG_RETURN(0); // Can't return anything here
}
/*
Function that executes an event in a child thread. Setups the
environment for the event execution and cleans after that.
SYNOPSIS
event_worker_thread()
arg The Event_timed object to be processed
RETURN VALUE
0 OK
*/
pthread_handler_t
event_worker_thread(void *arg)
{
THD *thd; /* needs to be first for thread_stack */
Worker_thread_param *param= (Worker_thread_param *) arg;
Event_timed *event= param->et;
int ret;
bool startup_error= FALSE;
Security_context *save_ctx;
/* this one is local and not needed after exec */
Security_context security_ctx;
DBUG_ENTER("event_worker_thread");
DBUG_PRINT("enter", ("event=[%s.%s]", event->dbname.str, event->name.str));
my_thread_init();
pthread_detach_this_thread();
if (!(thd= new THD) || init_event_thread(&thd, SYSTEM_THREAD_EVENT_WORKER))
{
sql_print_error("SCHEDULER: Startup failure.");
startup_error= TRUE;
event->spawn_thread_finish(thd);
}
else
event->set_thread_id(thd->thread_id);
DBUG_PRINT("info", ("master_access=%d db_access=%d",
thd->security_ctx->master_access, thd->security_ctx->db_access));
/*
If we don't change it before we send the signal back, then an intermittent
DROP EVENT will take LOCK_scheduler_data and try to kill this thread, because
event->thread_id is already real. However, because thd->security_ctx->user
is not initialized then a crash occurs in kill_one_thread(). Thus, we have
to change the context before sending the signal. We are under
LOCK_scheduler_data being held by Event_scheduler::run() -> ::execute_top().
*/
thd->change_security_context(event->definer_user, event->definer_host,
event->dbname, &security_ctx, &save_ctx);
DBUG_PRINT("info", ("master_access=%d db_access=%d",
thd->security_ctx->master_access, thd->security_ctx->db_access));
/* Signal the scheduler thread that we have started successfully */
pthread_mutex_lock(&param->LOCK_started);
param->started= TRUE;
pthread_cond_signal(&param->COND_started);
pthread_mutex_unlock(&param->LOCK_started);
if (!startup_error)
{
thd->init_for_queries();
thd->enable_slow_log= TRUE;
event->set_thread_id(thd->thread_id);
sql_print_information("SCHEDULER: [%s.%s of %s] executing in thread %lu",
event->dbname.str, event->name.str,
event->definer.str, thd->thread_id);
ret= event->execute(thd, thd->mem_root);
evex_print_warnings(thd, event);
sql_print_information("SCHEDULER: [%s.%s of %s] executed. RetCode=%d",
event->dbname.str, event->name.str,
event->definer.str, ret);
if (ret == EVEX_COMPILE_ERROR)
sql_print_information("SCHEDULER: COMPILE ERROR for event %s.%s of %s",
event->dbname.str, event->name.str,
event->definer.str);
else if (ret == EVEX_MICROSECOND_UNSUP)
sql_print_information("SCHEDULER: MICROSECOND is not supported");
DBUG_PRINT("info", ("master_access=%d db_access=%d",
thd->security_ctx->master_access, thd->security_ctx->db_access));
/* If true is returned, we are expected to free it */
if (event->spawn_thread_finish(thd))
{
DBUG_PRINT("info", ("Freeing object pointer"));
delete event;
}
}
if (thd)
{
thd->proc_info= "Clearing";
DBUG_ASSERT(thd->net.buff != 0);
/*
Free it here because net.vio is NULL for us => THD::~THD will check it
and won't call net_end(&net); See also replication code.
*/
net_end(&thd->net);
DBUG_PRINT("info", ("Worker thread %lu exiting", thd->thread_id));
VOID(pthread_mutex_lock(&LOCK_thread_count));
thread_count--;
thread_running--;
delete thd;
VOID(pthread_mutex_unlock(&LOCK_thread_count));
}
my_thread_end();
DBUG_RETURN(0); // Can't return anything here
}
/*
Constructor of class Event_scheduler.
SYNOPSIS
Event_scheduler::Event_scheduler()
*/
Event_scheduler::Event_scheduler()
{
thread_id= 0;
mutex_last_unlocked_at_line= mutex_last_locked_at_line= 0;
mutex_last_unlocked_in_func= mutex_last_locked_in_func= "";
cond_waiting_on= COND_NONE;
mutex_scheduler_data_locked= FALSE;
state= UNINITIALIZED;
start_scheduler_suspended= FALSE;
LOCK_scheduler_data= &LOCK_data;
}
/*
Returns the singleton instance of the class.
SYNOPSIS
Event_scheduler::create_instance()
RETURN VALUE
address
*/
void
Event_scheduler::create_instance(Event_queue *queue)
{
singleton= new Event_scheduler();
singleton->event_queue= queue;
}
/*
Returns the singleton instance of the class.
SYNOPSIS
Event_scheduler::get_instance()
RETURN VALUE
address
*/
Event_scheduler*
Event_scheduler::get_instance()
{
DBUG_ENTER("Event_scheduler::get_instance");
DBUG_RETURN(singleton);
}
/*
The implementation of full-fledged initialization.
SYNOPSIS
Event_scheduler::init()
RETURN VALUE
FALSE OK
TRUE Error
*/
bool
Event_scheduler::init(Event_db_repository *db_repo)
{
int i= 0;
bool ret= FALSE;
DBUG_ENTER("Event_scheduler::init");
DBUG_PRINT("enter", ("this=%p", this));
LOCK_SCHEDULER_DATA();
init_alloc_root(&scheduler_root, MEM_ROOT_BLOCK_SIZE, MEM_ROOT_PREALLOC);
for (;i < COND_LAST; i++)
if (pthread_cond_init(&cond_vars[i], NULL))
{
sql_print_error("SCHEDULER: Unable to initalize conditions");
ret= TRUE;
goto end;
}
state= INITIALIZED;
end:
UNLOCK_SCHEDULER_DATA();
DBUG_RETURN(ret);
}
/*
Frees all memory allocated by the scheduler object.
SYNOPSIS
Event_scheduler::destroy()
RETURN VALUE
FALSE OK
TRUE Error
*/
void
Event_scheduler::destroy()
{
DBUG_ENTER("Event_scheduler");
LOCK_SCHEDULER_DATA();
switch (state) {
case UNINITIALIZED:
break;
case INITIALIZED:
int i;
for (i= 0; i < COND_LAST; i++)
pthread_cond_destroy(&cond_vars[i]);
state= UNINITIALIZED;
break;
default:
sql_print_error("SCHEDULER: Destroying while state is %d", state);
/* I trust my code but ::safe() > ::sorry() */
DBUG_ASSERT(0);
break;
}
UNLOCK_SCHEDULER_DATA();
DBUG_VOID_RETURN;
}
extern pthread_attr_t connection_attrib;
/*
Starts the event scheduler
SYNOPSIS
Event_scheduler::start()
RETURN VALUE
FALSE OK
TRUE Error
*/
bool
Event_scheduler::start()
{
bool ret= FALSE;
pthread_t th;
DBUG_ENTER("Event_scheduler::start");
LOCK_SCHEDULER_DATA();
/* If already working or starting don't make another attempt */
DBUG_ASSERT(state == INITIALIZED);
if (state > INITIALIZED)
{
DBUG_PRINT("info", ("scheduler is already running or starting"));
ret= TRUE;
goto end;
}
/*
Now if another thread calls start it will bail-out because the branch
above will be executed. Thus no two or more child threads will be forked.
If the child thread cannot start for some reason then `state` is set
to CANTSTART and COND_started is also signaled. In this case we
set `state` back to INITIALIZED so another attempt to start the scheduler
can be made.
*/
state= COMMENCING;
/* Fork */
if (pthread_create(&th, &connection_attrib, event_scheduler_thread,
(void*)this))
{
DBUG_PRINT("error", ("cannot create a new thread"));
state= INITIALIZED;
ret= TRUE;
goto end;
}
/* Wait till the child thread has booted (w/ or wo success) */
while (!(state == SUSPENDED || state == RUNNING) && state != CANTSTART)
cond_wait(COND_started_or_stopped, LOCK_scheduler_data);
/*
If we cannot start for some reason then don't prohibit further attempts.
Set back to INITIALIZED.
*/
if (state == CANTSTART)
{
state= INITIALIZED;
ret= TRUE;
goto end;
}
end:
UNLOCK_SCHEDULER_DATA();
DBUG_RETURN(ret);
}
/*
Starts the event scheduler in suspended mode.
SYNOPSIS
Event_scheduler::start_suspended()
RETURN VALUE
TRUE OK
FALSE Error
*/
bool
Event_scheduler::start_suspended()
{
DBUG_ENTER("Event_scheduler::start_suspended");
start_scheduler_suspended= TRUE;
DBUG_RETURN(start());
}
/*
Report back that we cannot start. Used for ocasions where
we can't go into ::run() and have to report externally.
SYNOPSIS
Event_scheduler::report_error_during_start()
*/
inline void
Event_scheduler::report_error_during_start()
{
DBUG_ENTER("Event_scheduler::report_error_during_start");
LOCK_SCHEDULER_DATA();
state= CANTSTART;
DBUG_PRINT("info", ("Sending back COND_started_or_stopped"));
pthread_cond_signal(&cond_vars[COND_started_or_stopped]);
UNLOCK_SCHEDULER_DATA();
DBUG_VOID_RETURN;
}
/*
The internal loop of the event scheduler
SYNOPSIS
Event_scheduler::run()
thd Thread
RETURN VALUE
FALSE OK
TRUE Failure
*/
bool
Event_scheduler::run(THD *thd)
{
int ret;
struct timespec abstime;
DBUG_ENTER("Event_scheduler::run");
DBUG_PRINT("enter", ("thd=%p", thd));
LOCK_SCHEDULER_DATA();
ret= event_queue->load_events_from_db(thd);
if (!ret)
{
thread_id= thd->thread_id;
state= start_scheduler_suspended? SUSPENDED:RUNNING;
start_scheduler_suspended= FALSE;
}
else
state= CANTSTART;
DBUG_PRINT("info", ("Sending back COND_started_or_stopped"));
pthread_cond_signal(&cond_vars[COND_started_or_stopped]);
if (ret)
{
UNLOCK_SCHEDULER_DATA();
DBUG_RETURN(TRUE);
}
if (!check_n_suspend_if_needed(thd))
UNLOCK_SCHEDULER_DATA();
sql_print_information("SCHEDULER: Manager thread started with id %lu",
thd->thread_id);
abstime.tv_nsec= 0;
while ((state == SUSPENDED || state == RUNNING))
{
Event_timed *et;
LOCK_SCHEDULER_DATA();
if (check_n_wait_for_non_empty_queue(thd))
continue;
/* On TRUE data is unlocked, go back to the beginning */
if (check_n_suspend_if_needed(thd))
continue;
/* Guaranteed locked here */
if (state == IN_SHUTDOWN || shutdown_in_progress)
{
UNLOCK_SCHEDULER_DATA();
break;
}
DBUG_ASSERT(state == RUNNING);
// et= (Event_timed *)queue_top(&event_queue->queue);
et= event_queue->get_top();
/* Skip disabled events */
if (et->status != Event_timed::ENABLED)
{
/*
It could be a one-timer scheduled for a time, already in the past when the
scheduler was suspended.
*/
sql_print_information("SCHEDULER: Found a disabled event %*s.%*s in the queue",
et->dbname.length, et->dbname.str, et->name.length,
et->name.str);
queue_remove(&event_queue->queue, 0);
/* ToDo: check this again */
if (et->dropped)
et->drop(thd);
delete et;
UNLOCK_SCHEDULER_DATA();
continue;
}
thd->proc_info= (char *)"Computing";
DBUG_PRINT("evex manager",("computing time to sleep till next exec"));
/* Timestamp is in UTC */
abstime.tv_sec= sec_since_epoch_TIME(&et->execute_at);
thd->end_time();
if (abstime.tv_sec > thd->query_start())
{
/* Event trigger time is in the future */
thd->proc_info= (char *)"Sleep";
DBUG_PRINT("info", ("Going to sleep. Should wakeup after approx %d secs",
abstime.tv_sec - thd->query_start()));
DBUG_PRINT("info", ("Entering condition because waiting for activation"));
/*
Use THD::enter_cond()/exit_cond() or we won't be able to kill a
sleeping thread. Though ::stop() can do it by sending COND_new_work
an user can't by just issuing 'KILL x'; . In the latter case
pthread_cond_timedwait() will wait till `abstime`.
"Sleeping until next time"
*/
thd->enter_cond(&cond_vars[COND_new_work],LOCK_scheduler_data,"Sleeping");
pthread_cond_timedwait(&cond_vars[COND_new_work], LOCK_scheduler_data,
&abstime);
DBUG_PRINT("info", ("Manager woke up. state is %d", state));
/*
If we get signal we should recalculate the whether it's the right time
because there could be :
1. Spurious wake-up
2. The top of the queue was changed (new one becase of add/drop/replace)
*/
/* This will do implicit UNLOCK_SCHEDULER_DATA() */
thd->exit_cond("");
}
else
{
thd->proc_info= (char *)"Executing";
/*
Execute the event. An error may occur if a thread cannot be forked.
In this case stop the manager.
We should enter ::execute_top() with locked LOCK_scheduler_data.
*/
int ret= execute_top(thd, et);
UNLOCK_SCHEDULER_DATA();
if (ret)
break;
}
}
thd->proc_info= (char *)"Cleaning";
LOCK_SCHEDULER_DATA();
/*
It's possible that a user has used (SQL)COM_KILL. Hence set the appropriate
state because it is only set by ::stop().
*/
if (state != IN_SHUTDOWN)
{
DBUG_PRINT("info", ("We got KILL but the but not from ::stop()"));
state= IN_SHUTDOWN;
}
UNLOCK_SCHEDULER_DATA();
sql_print_information("SCHEDULER: Shutting down");
thd->proc_info= (char *)"Cleaning queue";
clean_memory(thd);
THD_CHECK_SENTRY(thd);
/* free mamager_root memory but don't destroy the root */
thd->proc_info= (char *)"Cleaning memory root";
free_root(&scheduler_root, MYF(0));
THD_CHECK_SENTRY(thd);
/*
We notify the waiting thread which shutdowns us that we have cleaned.
There are few more instructions to be executed in this pthread but
they don't affect manager structures thus it's safe to signal already
at this point.
*/
LOCK_SCHEDULER_DATA();
thd->proc_info= (char *)"Sending shutdown signal";
DBUG_PRINT("info", ("Sending COND_started_or_stopped"));
if (state == IN_SHUTDOWN)
pthread_cond_signal(&cond_vars[COND_started_or_stopped]);
state= INITIALIZED;
/*
We set it here because ::run() can stop not only because of ::stop()
call but also because of `KILL x`
*/
thread_id= 0;
sql_print_information("SCHEDULER: Stopped");
UNLOCK_SCHEDULER_DATA();
/* We have modified, we set back */
thd->query= NULL;
thd->query_length= 0;
DBUG_RETURN(FALSE);
}
/*
Executes the top element of the queue. Auxiliary method for ::run().
SYNOPSIS
Event_scheduler::execute_top()
RETURN VALUE
FALSE OK
TRUE Failure
NOTE
NO locking is done. EXPECTED is that the caller should have locked
the queue (w/ LOCK_scheduler_data).
*/
bool
Event_scheduler::execute_top(THD *thd, Event_timed *et)
{
int spawn_ret_code;
bool ret= FALSE;
DBUG_ENTER("Event_scheduler::execute_top");
DBUG_PRINT("enter", ("thd=%p", thd));
/* Is it good idea to pass a stack address ?*/
Worker_thread_param param(et);
pthread_mutex_lock(&param.LOCK_started);
/*
We don't lock LOCK_scheduler_data fpr workers_increment() because it's a
pre-requisite for calling the current_method.
*/
switch ((spawn_ret_code= et->spawn_now(event_worker_thread, &param))) {
case EVENT_EXEC_CANT_FORK:
/*
We don't lock LOCK_scheduler_data here because it's a pre-requisite
for calling the current_method.
*/
sql_print_error("SCHEDULER: Problem while trying to create a thread");
ret= TRUE;
break;
case EVENT_EXEC_ALREADY_EXEC:
/*
We don't lock LOCK_scheduler_data here because it's a pre-requisite
for calling the current_method.
*/
sql_print_information("SCHEDULER: %s.%s in execution. Skip this time.",
et->dbname.str, et->name.str);
if ((et->flags & EVENT_EXEC_NO_MORE) || et->status == Event_timed::DISABLED)
event_queue->remove_top();
else
event_queue->top_changed();
break;
default:
DBUG_ASSERT(!spawn_ret_code);
if ((et->flags & EVENT_EXEC_NO_MORE) || et->status == Event_timed::DISABLED)
event_queue->remove_top();
else
event_queue->top_changed();
/*
We don't lock LOCK_scheduler_data here because it's a pre-requisite
for calling the current_method.
*/
if (likely(!spawn_ret_code))
{
/* Wait the forked thread to start */
do {
pthread_cond_wait(&param.COND_started, &param.LOCK_started);
} while (!param.started);
}
/*
param was allocated on the stack so no explicit delete as well as
in this moment it's no more used in the spawned thread so it's safe
to be deleted.
*/
break;
}
pthread_mutex_unlock(&param.LOCK_started);
/* `param` is on the stack and will be destructed by the compiler */
DBUG_RETURN(ret);
}
/*
Cleans the scheduler's queue. Auxiliary method for ::run().
SYNOPSIS
Event_scheduler::clean_queue()
thd Thread
*/
void
Event_scheduler::clean_memory(THD *thd)
{
CHARSET_INFO *scs= system_charset_info;
uint i;
DBUG_ENTER("Event_scheduler::clean_queue");
DBUG_PRINT("enter", ("thd=%p", thd));
LOCK_SCHEDULER_DATA();
stop_all_running_events(thd);
UNLOCK_SCHEDULER_DATA();
sql_print_information("SCHEDULER: Emptying the queue");
event_queue->empty_queue();
DBUG_VOID_RETURN;
}
/*
Stops all running events
SYNOPSIS
Event_scheduler::stop_all_running_events()
thd Thread
NOTE
LOCK_scheduler data must be acquired prior to call to this method
*/
void
Event_scheduler::stop_all_running_events(THD *thd)
{
CHARSET_INFO *scs= system_charset_info;
uint i;
DYNAMIC_ARRAY running_threads;
THD *tmp;
DBUG_ENTER("Event_scheduler::stop_all_running_events");
DBUG_PRINT("enter", ("workers_count=%d", workers_count()));
my_init_dynamic_array(&running_threads, sizeof(ulong), 10, 10);
bool had_super= FALSE;
VOID(pthread_mutex_lock(&LOCK_thread_count)); // For unlink from list
I_List_iterator<THD> it(threads);
while ((tmp=it++))
{
if (tmp->command == COM_DAEMON)
continue;
if (tmp->system_thread == SYSTEM_THREAD_EVENT_WORKER)
push_dynamic(&running_threads, (gptr) &tmp->thread_id);
}
VOID(pthread_mutex_unlock(&LOCK_thread_count));
/* We need temporarily SUPER_ACL to be able to kill our offsprings */
if (!(thd->security_ctx->master_access & SUPER_ACL))
thd->security_ctx->master_access|= SUPER_ACL;
else
had_super= TRUE;
char tmp_buff[10*STRING_BUFFER_USUAL_SIZE];
char int_buff[STRING_BUFFER_USUAL_SIZE];
String tmp_string(tmp_buff, sizeof(tmp_buff), scs);
String int_string(int_buff, sizeof(int_buff), scs);
tmp_string.length(0);
for (i= 0; i < running_threads.elements; ++i)
{
int ret;
ulong thd_id= *dynamic_element(&running_threads, i, ulong*);
int_string.set((longlong) thd_id,scs);
tmp_string.append(int_string);
if (i < running_threads.elements - 1)
tmp_string.append(' ');
if ((ret= kill_one_thread(thd, thd_id, FALSE)))
{
sql_print_error("SCHEDULER: Error killing %lu code=%d", thd_id, ret);
break;
}
}
if (running_threads.elements)
sql_print_information("SCHEDULER: Killing workers :%s", tmp_string.c_ptr());
if (!had_super)
thd->security_ctx->master_access &= ~SUPER_ACL;
delete_dynamic(&running_threads);
sql_print_information("SCHEDULER: Waiting for worker threads to finish");
while (workers_count())
my_sleep(100000);
DBUG_VOID_RETURN;
}
/*
Stops the event scheduler
SYNOPSIS
Event_scheduler::stop()
RETURN VALUE
OP_OK OK
OP_CANT_KILL Error during stopping of manager thread
OP_NOT_RUNNING Manager not working
NOTE
The caller must have acquited LOCK_scheduler_data.
*/
int
Event_scheduler::stop()
{
THD *thd= current_thd;
DBUG_ENTER("Event_scheduler::stop");
DBUG_PRINT("enter", ("thd=%p", current_thd));
LOCK_SCHEDULER_DATA();
if (!(state == SUSPENDED || state == RUNNING))
{
/*
One situation to be here is if there was a start that forked a new
thread but the new thread did not acquire yet LOCK_scheduler_data.
Hence, in this case return an error.
*/
DBUG_PRINT("info", ("manager not running but %d. doing nothing", state));
UNLOCK_SCHEDULER_DATA();
DBUG_RETURN(OP_NOT_RUNNING);
}
state= IN_SHUTDOWN;
DBUG_PRINT("info", ("Manager thread has id %d", thread_id));
sql_print_information("SCHEDULER: Killing manager thread %lu", thread_id);
/*
Sending the COND_new_work to ::run() is a way to get this working without
race conditions. If we use kill_one_thread() it will call THD::awake() and
because in ::run() both THD::enter_cond()/::exit_cond() are used,
THD::awake() will try to lock LOCK_scheduler_data. If we UNLOCK it before,
then the pthread_cond_signal(COND_started_or_stopped) could be signaled in
::run() and we can miss the signal before we relock. A way is to use
another mutex for this shutdown procedure but better not.
*/
pthread_cond_signal(&cond_vars[COND_new_work]);
/* Or we are suspended - then we should wake up */
pthread_cond_signal(&cond_vars[COND_suspend_or_resume]);
/* Guarantee we don't catch spurious signals */
sql_print_information("SCHEDULER: Waiting the manager thread to reply");
while (state != INITIALIZED)
{
DBUG_PRINT("info", ("Waiting for COND_started_or_stopped from the manager "
"thread. Current value of state is %d . "
"workers count=%d", state, workers_count()));
cond_wait(COND_started_or_stopped, LOCK_scheduler_data);
}
DBUG_PRINT("info", ("Manager thread has cleaned up. Set state to INIT"));
UNLOCK_SCHEDULER_DATA();
DBUG_RETURN(OP_OK);
}
/*
Suspends or resumes the scheduler.
SUSPEND - it won't execute any event till resumed.
RESUME - it will resume if suspended.
SYNOPSIS
Event_scheduler::suspend_or_resume()
RETURN VALUE
OP_OK OK
*/
int
Event_scheduler::suspend_or_resume(
enum Event_scheduler::enum_suspend_or_resume action)
{
DBUG_ENTER("Event_scheduler::suspend_or_resume");
DBUG_PRINT("enter", ("action=%d", action));
LOCK_SCHEDULER_DATA();
if ((action == SUSPEND && state == SUSPENDED) ||
(action == RESUME && state == RUNNING))
{
DBUG_PRINT("info", ("Either trying to suspend suspended or resume "
"running scheduler. Doing nothing."));
}
else
{
/* Wake the main thread up if he is asleep */
DBUG_PRINT("info", ("Sending signal"));
if (action==SUSPEND)
{
state= SUSPENDED;
pthread_cond_signal(&cond_vars[COND_new_work]);
}
else
{
state= RUNNING;
pthread_cond_signal(&cond_vars[COND_suspend_or_resume]);
}
DBUG_PRINT("info", ("Waiting on COND_suspend_or_resume"));
cond_wait(COND_suspend_or_resume, LOCK_scheduler_data);
DBUG_PRINT("info", ("Got response"));
}
UNLOCK_SCHEDULER_DATA();
DBUG_RETURN(OP_OK);
}
/*
Returns the number of executing events.
SYNOPSIS
Event_scheduler::workers_count()
*/
uint
Event_scheduler::workers_count()
{
THD *tmp;
uint count= 0;
DBUG_ENTER("Event_scheduler::workers_count");
VOID(pthread_mutex_lock(&LOCK_thread_count)); // For unlink from list
I_List_iterator<THD> it(threads);
while ((tmp=it++))
{
if (tmp->command == COM_DAEMON)
continue;
if (tmp->system_thread == SYSTEM_THREAD_EVENT_WORKER)
++count;
}
VOID(pthread_mutex_unlock(&LOCK_thread_count));
DBUG_PRINT("exit", ("%d", count));
DBUG_RETURN(count);
}
/*
Checks and suspends if needed
SYNOPSIS
Event_scheduler::check_n_suspend_if_needed()
thd Thread
RETURN VALUE
FALSE Not suspended, we haven't slept
TRUE We were suspended. LOCK_scheduler_data is unlocked.
NOTE
The caller should have locked LOCK_scheduler_data!
The mutex will be unlocked in case this function returns TRUE
*/
bool
Event_scheduler::check_n_suspend_if_needed(THD *thd)
{
bool was_suspended= FALSE;
DBUG_ENTER("Event_scheduler::check_n_suspend_if_needed");
if (thd->killed && !shutdown_in_progress)
{
state= SUSPENDED;
thd->killed= THD::NOT_KILLED;
}
if (state == SUSPENDED)
{
thd->enter_cond(&cond_vars[COND_suspend_or_resume], LOCK_scheduler_data,
"Suspended");
/* Send back signal to the thread that asked us to suspend operations */
pthread_cond_signal(&cond_vars[COND_suspend_or_resume]);
sql_print_information("SCHEDULER: Suspending operations");
was_suspended= TRUE;
}
while (state == SUSPENDED)
{
cond_wait(COND_suspend_or_resume, LOCK_scheduler_data);
DBUG_PRINT("info", ("Woke up after waiting on COND_suspend_or_resume"));
if (state != SUSPENDED)
{
pthread_cond_signal(&cond_vars[COND_suspend_or_resume]);
sql_print_information("SCHEDULER: Resuming operations");
}
}
if (was_suspended)
{
event_queue->recalculate_queue(thd);
/* This will implicitly unlock LOCK_scheduler_data */
thd->exit_cond("");
}
DBUG_RETURN(was_suspended);
}
/*
Checks for empty queue and waits till new element gets in
SYNOPSIS
Event_scheduler::check_n_wait_for_non_empty_queue()
thd Thread
RETURN VALUE
FALSE Did not wait - LOCK_scheduler_data still locked.
TRUE Waited - LOCK_scheduler_data unlocked.
NOTE
The caller should have locked LOCK_scheduler_data!
*/
bool
Event_scheduler::check_n_wait_for_non_empty_queue(THD *thd)
{
bool slept= FALSE;
DBUG_ENTER("Event_scheduler::check_n_wait_for_non_empty_queue");
DBUG_PRINT("enter", ("q.elements=%lu state=%s",
event_queue->events_count_no_lock(), states_names[state]));
if (!event_queue->events_count_no_lock())
thd->enter_cond(&cond_vars[COND_new_work], LOCK_scheduler_data,
"Empty queue, sleeping");
/* Wait in a loop protecting against catching spurious signals */
while (!event_queue->events_count_no_lock() && state == RUNNING)
{
slept= TRUE;
DBUG_PRINT("info", ("Entering condition because of empty queue"));
cond_wait(COND_new_work, LOCK_scheduler_data);
DBUG_PRINT("info", ("Manager woke up. Hope we have events now. state=%d",
state));
/*
exit_cond does implicit mutex_UNLOCK, we needed it locked if
1. we loop again
2. end the current loop and start doing calculations
*/
}
if (slept)
thd->exit_cond("");
DBUG_PRINT("exit", ("q.elements=%lu state=%s thd->killed=%d",
event_queue->events_count_no_lock(), states_names[state], thd->killed));
DBUG_RETURN(slept);
}
/*
Returns the current state of the scheduler
SYNOPSIS
Event_scheduler::get_state()
*/
enum Event_scheduler::enum_state
Event_scheduler::get_state()
{
enum Event_scheduler::enum_state ret;
DBUG_ENTER("Event_scheduler::get_state");
/* lock_data & unlock_data are not static */
pthread_mutex_lock(singleton->LOCK_scheduler_data);
ret= singleton->state;
pthread_mutex_unlock(singleton->LOCK_scheduler_data);
DBUG_RETURN(ret);
}
/*
Returns whether the scheduler was initialized.
SYNOPSIS
Event_scheduler::initialized()
RETURN VALUE
FALSE Was not initialized so far
TRUE Was initialized
*/
bool
Event_scheduler::initialized()
{
DBUG_ENTER("Event_scheduler::initialized");
DBUG_RETURN(Event_scheduler::get_state() != UNINITIALIZED);
}
/*
Dumps some data about the internal status of the scheduler.
SYNOPSIS
Event_scheduler::dump_internal_status()
thd THD
RETURN VALUE
0 OK
1 Error
*/
int
Event_scheduler::dump_internal_status(THD *thd)
{
DBUG_ENTER("dump_internal_status");
#ifndef DBUG_OFF
CHARSET_INFO *scs= system_charset_info;
Protocol *protocol= thd->protocol;
List<Item> field_list;
int ret;
char tmp_buff[5*STRING_BUFFER_USUAL_SIZE];
char int_buff[STRING_BUFFER_USUAL_SIZE];
String tmp_string(tmp_buff, sizeof(tmp_buff), scs);
String int_string(int_buff, sizeof(int_buff), scs);
tmp_string.length(0);
int_string.length(0);
field_list.push_back(new Item_empty_string("Name", 20));
field_list.push_back(new Item_empty_string("Value",20));
if (protocol->send_fields(&field_list, Protocol::SEND_NUM_ROWS |
Protocol::SEND_EOF))
DBUG_RETURN(1);
protocol->prepare_for_resend();
protocol->store(STRING_WITH_LEN("state"), scs);
protocol->store(states_names[singleton->state].str,
states_names[singleton->state].length,
scs);
ret= protocol->write();
/*
If not initialized - don't show anything else. get_instance()
will otherwise implicitly initialize it. We don't want that.
*/
if (singleton->state >= INITIALIZED)
{
/* last locked at*/
/*
The first thing to do, or get_instance() will overwrite the values.
mutex_last_locked_at_line / mutex_last_unlocked_at_line
*/
protocol->prepare_for_resend();
protocol->store(STRING_WITH_LEN("last locked at"), scs);
tmp_string.length(scs->cset->snprintf(scs, (char*) tmp_string.ptr(),
tmp_string.alloced_length(), "%s::%d",
singleton->mutex_last_locked_in_func,
singleton->mutex_last_locked_at_line));
protocol->store(&tmp_string);
ret= protocol->write();
/* last unlocked at*/
protocol->prepare_for_resend();
protocol->store(STRING_WITH_LEN("last unlocked at"), scs);
tmp_string.length(scs->cset->snprintf(scs, (char*) tmp_string.ptr(),
tmp_string.alloced_length(), "%s::%d",
singleton->mutex_last_unlocked_in_func,
singleton->mutex_last_unlocked_at_line));
protocol->store(&tmp_string);
ret= protocol->write();
/* waiting on */
protocol->prepare_for_resend();
protocol->store(STRING_WITH_LEN("waiting on condition"), scs);
tmp_string.length(scs->cset->
snprintf(scs, (char*) tmp_string.ptr(),
tmp_string.alloced_length(), "%s",
(singleton->cond_waiting_on != COND_NONE) ?
cond_vars_names[singleton->cond_waiting_on]:
"NONE"));
protocol->store(&tmp_string);
ret= protocol->write();
Event_scheduler *scheduler= get_instance();
/* workers_count */
protocol->prepare_for_resend();
protocol->store(STRING_WITH_LEN("workers_count"), scs);
int_string.set((longlong) scheduler->workers_count(), scs);
protocol->store(&int_string);
ret= protocol->write();
/* queue.elements */
protocol->prepare_for_resend();
protocol->store(STRING_WITH_LEN("queue.elements"), scs);
int_string.set((longlong) scheduler->event_queue->events_count_no_lock(), scs);
protocol->store(&int_string);
ret= protocol->write();
/* scheduler_data_locked */
protocol->prepare_for_resend();
protocol->store(STRING_WITH_LEN("scheduler data locked"), scs);
int_string.set((longlong) scheduler->mutex_scheduler_data_locked, scs);
protocol->store(&int_string);
ret= protocol->write();
}
send_eof(thd);
#endif
DBUG_RETURN(0);
}
/*
Wrapper for pthread_mutex_lock
SYNOPSIS
Event_scheduler::lock_data()
mutex Mutex to lock
line The line number on which the lock is done
RETURN VALUE
Error code of pthread_mutex_lock()
*/
void
Event_scheduler::lock_data(const char *func, uint line)
{
DBUG_ENTER("Event_scheduler::lock_mutex");
DBUG_PRINT("enter", ("mutex_lock=%p func=%s line=%u",
&LOCK_scheduler_data, func, line));
pthread_mutex_lock(LOCK_scheduler_data);
mutex_last_locked_in_func= func;
mutex_last_locked_at_line= line;
mutex_scheduler_data_locked= TRUE;
DBUG_VOID_RETURN;
}
/*
Wrapper for pthread_mutex_unlock
SYNOPSIS
Event_scheduler::unlock_data()
mutex Mutex to unlock
line The line number on which the unlock is done
*/
void
Event_scheduler::unlock_data(const char *func, uint line)
{
DBUG_ENTER("Event_scheduler::UNLOCK_mutex");
DBUG_PRINT("enter", ("mutex_unlock=%p func=%s line=%u",
LOCK_scheduler_data, func, line));
mutex_last_unlocked_at_line= line;
mutex_scheduler_data_locked= FALSE;
mutex_last_unlocked_in_func= func;
pthread_mutex_unlock(LOCK_scheduler_data);
DBUG_VOID_RETURN;
}
/*
Wrapper for pthread_cond_wait
SYNOPSIS
Event_scheduler::cond_wait()
cond Conditional to wait for
mutex Mutex of the conditional
RETURN VALUE
Error code of pthread_cond_wait()
*/
int
Event_scheduler::cond_wait(int cond, pthread_mutex_t *mutex)
{
int ret;
DBUG_ENTER("Event_scheduler::cond_wait");
DBUG_PRINT("enter", ("cond=%s mutex=%p", cond_vars_names[cond], mutex));
ret= pthread_cond_wait(&cond_vars[cond_waiting_on=cond], mutex);
cond_waiting_on= COND_NONE;
DBUG_RETURN(ret);
}
/*
Signals the main scheduler thread that the queue has changed
its state.
SYNOPSIS
Event_scheduler::queue_changed()
*/
void
Event_scheduler::queue_changed()
{
DBUG_ENTER("Event_scheduler::queue_changed");
DBUG_PRINT("info", ("Sending COND_new_work"));
pthread_cond_signal(&cond_vars[COND_new_work]);
DBUG_VOID_RETURN;
}
/*
Inits mutexes.
SYNOPSIS
Event_scheduler::init_mutexes()
*/
void
Event_scheduler::init_mutexes()
{
pthread_mutex_init(singleton->LOCK_scheduler_data, MY_MUTEX_INIT_FAST);
}
/*
Destroys mutexes.
SYNOPSIS
Event_queue::destroy_mutexes()
*/
void
Event_scheduler::destroy_mutexes()
{
pthread_mutex_destroy(singleton->LOCK_scheduler_data);
}
sql/event_scheduler.h
View file @ b9a7fe27
......@@ -16,191 +16,4 @@
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
class sp_name;
class Event_timed;
class Event_db_repository;
class Event_queue;
class THD;
int
events_init();
void
events_shutdown();
#include "event_queue.h"
#include "event_scheduler.h"
class Event_scheduler
{
public:
enum enum_state
{
UNINITIALIZED= 0,
INITIALIZED,
COMMENCING,
CANTSTART,
RUNNING,
SUSPENDED,
IN_SHUTDOWN
};
enum enum_suspend_or_resume
{
SUSPEND= 1,
RESUME= 2
};
/* This is the current status of the life-cycle of the scheduler. */
enum enum_state state;
static void
create_instance(Event_queue *queue);
static void
init_mutexes();
static void
destroy_mutexes();
/* Singleton access */
static Event_scheduler*
get_instance();
bool
init(Event_db_repository *db_repo);
void
destroy();
/* State changing methods follow */
bool
start();
int
stop();
bool
start_suspended();
/*
Need to be public because has to be called from the function
passed to pthread_create.
*/
bool
run(THD *thd);
int
suspend_or_resume(enum enum_suspend_or_resume action);
/*
static void
init_mutexes();
static void
destroy_mutexes();
*/
void
report_error_during_start();
/* Information retrieving methods follow */
enum enum_state
get_state();
bool
initialized();
static int
dump_internal_status(THD *thd);
/* helper functions for working with mutexes & conditionals */
void
lock_data(const char *func, uint line);
void
unlock_data(const char *func, uint line);
int
cond_wait(int cond, pthread_mutex_t *mutex);
void
queue_changed();
Event_queue *event_queue;
protected:
uint
workers_count();
/* helper functions */
bool
execute_top(THD *thd, Event_timed *et);
void
clean_memory(THD *thd);
void
stop_all_running_events(THD *thd);
bool
check_n_suspend_if_needed(THD *thd);
bool
check_n_wait_for_non_empty_queue(THD *thd);
/* Singleton DP is used */
Event_scheduler();
pthread_mutex_t LOCK_data;
pthread_mutex_t *LOCK_scheduler_data;
/* The MEM_ROOT of the object */
MEM_ROOT scheduler_root;
/* Set to start the scheduler in suspended state */
bool start_scheduler_suspended;
/*
Holds the thread id of the executor thread or 0 if the executor is not
running. It is used by ::shutdown() to know which thread to kill with
kill_one_thread(). The latter wake ups a thread if it is waiting on a
conditional variable and sets thd->killed to non-zero.
*/
ulong thread_id;
enum enum_cond_vars
{
COND_NONE= -1,
COND_new_work= 0,
COND_started_or_stopped,
COND_suspend_or_resume,
/* Must be always last */
COND_LAST
};
uint mutex_last_locked_at_line;
uint mutex_last_unlocked_at_line;
const char* mutex_last_locked_in_func;
const char* mutex_last_unlocked_in_func;
int cond_waiting_on;
bool mutex_scheduler_data_locked;
static const char * const cond_vars_names[COND_LAST];
pthread_cond_t cond_vars[COND_LAST];
/* Singleton instance */
static Event_scheduler *singleton;
private:
/* Prevent use of these */
Event_scheduler(const Event_scheduler &);
void operator=(Event_scheduler &);
};
#endif /* _EVENT_SCHEDULER_H_ */
sql/event_scheduler_ng.cc
View file @ b9a7fe27
......@@ -212,6 +212,7 @@ end:
pthread_mutex_unlock(&LOCK_thread_count);
my_thread_end();
DBUG_RETURN(0); // Against gcc warnings
}
......@@ -296,26 +297,22 @@ end:
delete event;
my_thread_end();
DBUG_RETURN(0); // Against gcc warnings
}
bool
Event_scheduler_ng::init(Event_queue *q)
Event_scheduler_ng::init_scheduler(Event_queue *q)
{
thread_id= 0;
state= INITIALIZED;
/* init memory root */
queue= q;
return FALSE;
}
void
Event_scheduler_ng::deinit()
{
}
Event_scheduler_ng::deinit_scheduler() {}
void
......@@ -477,7 +474,6 @@ Event_scheduler_ng::run(THD *thd)
pthread_cond_signal(&COND_state);
error:
state= INITIALIZED;
stop_all_running_events(thd);
UNLOCK_SCHEDULER_DATA();
sql_print_information("SCHEDULER: Stopped");
......@@ -560,98 +556,18 @@ Event_scheduler_ng::workers_count()
}
/*
Stops all running events
SYNOPSIS
Event_scheduler::stop_all_running_events()
thd Thread
NOTE
LOCK_scheduler data must be acquired prior to call to this method
*/
void
Event_scheduler_ng::stop_all_running_events(THD *thd)
{
CHARSET_INFO *scs= system_charset_info;
uint i;
DYNAMIC_ARRAY running_threads;
THD *tmp;
DBUG_ENTER("Event_scheduler::stop_all_running_events");
DBUG_PRINT("enter", ("workers_count=%d", workers_count()));
my_init_dynamic_array(&running_threads, sizeof(ulong), 10, 10);
bool had_super= FALSE;
VOID(pthread_mutex_lock(&LOCK_thread_count)); // For unlink from list
I_List_iterator<THD> it(threads);
while ((tmp=it++))
{
if (tmp->command == COM_DAEMON)
continue;
if (tmp->system_thread == SYSTEM_THREAD_EVENT_WORKER)
push_dynamic(&running_threads, (gptr) &tmp->thread_id);
}
VOID(pthread_mutex_unlock(&LOCK_thread_count));
/* We need temporarily SUPER_ACL to be able to kill our offsprings */
if (!(thd->security_ctx->master_access & SUPER_ACL))
thd->security_ctx->master_access|= SUPER_ACL;
else
had_super= TRUE;
char tmp_buff[10*STRING_BUFFER_USUAL_SIZE];
char int_buff[STRING_BUFFER_USUAL_SIZE];
String tmp_string(tmp_buff, sizeof(tmp_buff), scs);
String int_string(int_buff, sizeof(int_buff), scs);
tmp_string.length(0);
for (i= 0; i < running_threads.elements; ++i)
{
int ret;
ulong thd_id= *dynamic_element(&running_threads, i, ulong*);
int_string.set((longlong) thd_id,scs);
tmp_string.append(int_string);
if (i < running_threads.elements - 1)
tmp_string.append(' ');
if ((ret= kill_one_thread(thd, thd_id, FALSE)))
{
sql_print_error("SCHEDULER: Error killing %lu code=%d", thd_id, ret);
break;
}
}
if (running_threads.elements)
sql_print_information("SCHEDULER: Killing workers :%s", tmp_string.c_ptr());
if (!had_super)
thd->security_ctx->master_access &= ~SUPER_ACL;
delete_dynamic(&running_threads);
sql_print_information("SCHEDULER: Waiting for worker threads to finish");
while (workers_count())
my_sleep(100000);
DBUG_VOID_RETURN;
}
/*
Signals the main scheduler thread that the queue has changed
its state.
SYNOPSIS
Event_scheduler::queue_changed()
Event_scheduler_ng::queue_changed()
*/
void
Event_scheduler_ng::queue_changed()
{
DBUG_ENTER("Event_scheduler::queue_changed");
DBUG_ENTER("Event_scheduler_ng::queue_changed");
DBUG_PRINT("info", ("Sending COND_state"));
pthread_cond_signal(&COND_state);
DBUG_VOID_RETURN;
......@@ -662,8 +578,7 @@ void
Event_scheduler_ng::lock_data(const char *func, uint line)
{
DBUG_ENTER("Event_scheduler_ng::lock_mutex");
DBUG_PRINT("enter", ("mutex_lock=%p func=%s line=%u",
&LOCK_scheduler_state, func, line));
DBUG_PRINT("enter", ("func=%s line=%u", func, line));
pthread_mutex_lock(&LOCK_scheduler_state);
mutex_last_locked_in_func= func;
mutex_last_locked_at_line= line;
......@@ -675,9 +590,8 @@ Event_scheduler_ng::lock_data(const char *func, uint line)
void
Event_scheduler_ng::unlock_data(const char *func, uint line)
{
DBUG_ENTER("Event_scheduler_ng::UNLOCK_mutex");
DBUG_PRINT("enter", ("mutex_unlock=%p func=%s line=%u",
&LOCK_scheduler_state, func, line));
DBUG_ENTER("Event_scheduler_ng::unlock_mutex");
DBUG_PRINT("enter", ("func=%s line=%u", func, line));
mutex_last_unlocked_at_line= line;
mutex_scheduler_data_locked= FALSE;
mutex_last_unlocked_in_func= func;
......
sql/event_scheduler_ng.h
View file @ b9a7fe27
......@@ -48,10 +48,10 @@ public:
run(THD *thd);
bool
init(Event_queue *queue);
init_scheduler(Event_queue *queue);
void
deinit();
deinit_scheduler();
void
init_mutexes();
......@@ -78,9 +78,6 @@ private:
bool
execute_top(THD *thd, Event_timed *job_data);
void
stop_all_running_events(THD *thd);
/* helper functions for working with mutexes & conditionals */
void
lock_data(const char *func, uint line);
......@@ -104,7 +101,6 @@ private:
pthread_cond_t COND_state;
Event_queue *queue;
Event_db_repository *db_repository;
uint mutex_last_locked_at_line;
uint mutex_last_unlocked_at_line;
......
sql/events.cc
View file @ b9a7fe27
......@@ -17,10 +17,10 @@
#include "mysql_priv.h"
#include "events.h"
#include "event_data_objects.h"
#include "event_scheduler.h"
#include "event_db_repository.h"
#include "sp_head.h"
#include "event_queue.h"
#include "event_scheduler_ng.h"
#include "sp_head.h"
/*
TODO list :
......@@ -48,6 +48,21 @@ Warning:
*/
/*
If the user (un)intentionally removes an event directly from mysql.event
the following sequence has to be used to be able to remove the in-memory
counterpart.
1. CREATE EVENT the_name ON SCHEDULE EVERY 1 SECOND DISABLE DO SELECT 1;
2. DROP EVENT the_name
In other words, the first one will create a row in mysql.event . In the
second step because there will be a line, disk based drop will pass and
the scheduler will remove the memory counterpart. The reason is that
in-memory queue does not check whether the event we try to drop from memory
is disabled. Disabled events are not kept in-memory because they are not
eligible for execution.
*/
const char *event_scheduler_state_names[]=
{ "OFF", "0", "ON", "1", "SUSPEND", "2", NullS };
......@@ -284,17 +299,15 @@ Events::open_event_table(THD *thd, enum thr_lock_type lock_type,
*/
int
Events::create_event(THD *thd, Event_parse_data *parse_data, uint create_options,
Events::create_event(THD *thd, Event_parse_data *parse_data, bool if_not_exists,
uint *rows_affected)
{
int ret;
DBUG_ENTER("Events::create_event");
if (!(ret= db_repository->
create_event(thd, parse_data,
create_options & HA_LEX_CREATE_IF_NOT_EXISTS,
if (!(ret= db_repository->create_event(thd, parse_data, if_not_exists,
rows_affected)))
{
if ((ret= event_queue->create_event(thd, parse_data, true)))
if ((ret= event_queue->create_event(thd, parse_data)))
my_error(ER_EVENT_MODIFY_QUEUE_ERROR, MYF(0), ret);
}
/* No need to close the table, it will be closed in sql_parse::do_command */
......@@ -350,9 +363,10 @@ Events::update_event(THD *thd, Event_parse_data *parse_data, sp_name *new_name,
SYNOPSIS
Events::drop_event()
thd THD
name event's name
drop_if_exists if set and the event not existing => warning onto the stack
rows_affected affected number of rows is returned heres
name Event's name
if_exists When set and the event does not exist => warning onto
the stack
rows_affected Affected number of rows is returned heres
RETURN VALUE
0 OK
......@@ -360,15 +374,13 @@ Events::update_event(THD *thd, Event_parse_data *parse_data, sp_name *new_name,
*/
int
Events::drop_event(THD *thd, sp_name *name, bool drop_if_exists,
uint *rows_affected)
Events::drop_event(THD *thd, sp_name *name, bool if_exists, uint *rows_affected)
{
int ret;
DBUG_ENTER("Events::drop_event");
if (!(ret= db_repository->drop_event(thd, name->m_db, name->m_name,
drop_if_exists, rows_affected)))
if (!(ret= db_repository->drop_event(thd, name->m_db, name->m_name, if_exists,
rows_affected)))
{
if ((ret= event_queue->drop_event(thd, name)))
my_error(ER_EVENT_MODIFY_QUEUE_ERROR, MYF(0), ret);
......@@ -401,7 +413,7 @@ Events::show_create_event(THD *thd, sp_name *spn)
DBUG_PRINT("enter", ("name: %*s", spn->m_name.length, spn->m_name.str));
thd->reset_n_backup_open_tables_state(&backup);
ret= db_repository->find_event(thd, spn->m_db, spn->m_name, &et, NULL, thd->mem_root);
ret= db_repository->find_event(thd, spn->m_db, spn->m_name, &et, NULL);
thd->restore_backup_open_tables_state(&backup);
if (!ret)
......@@ -472,7 +484,7 @@ Events::drop_schema_events(THD *thd, char *db)
DBUG_ENTER("evex_drop_db_events");
DBUG_PRINT("enter", ("dropping events from %s", db));
ret= event_queue->drop_schema_events(thd, db_lex);
event_queue->drop_schema_events(thd, db_lex);
ret= db_repository->drop_schema_events(thd, db_lex);
DBUG_RETURN(ret);
......@@ -500,9 +512,8 @@ Events::init()
Event_db_repository *db_repo;
DBUG_ENTER("Events::init");
db_repository->init_repository();
event_queue->init(db_repository);
event_queue->scheduler= scheduler_ng;
scheduler_ng->init(event_queue);
event_queue->init_queue(db_repository, scheduler_ng);
scheduler_ng->init_scheduler(event_queue);
/* it should be an assignment! */
if (opt_event_scheduler)
......@@ -532,8 +543,9 @@ Events::deinit()
DBUG_ENTER("Events::deinit");
scheduler_ng->stop();
scheduler_ng->deinit();
event_queue->deinit();
scheduler_ng->deinit_scheduler();
event_queue->deinit_queue();
db_repository->deinit_repository();
DBUG_VOID_RETURN;
......
sql/events.h
View file @ b9a7fe27
......@@ -75,7 +75,7 @@ public:
get_instance();
int
create_event(THD *thd, Event_parse_data *parse_data, uint create_options,
create_event(THD *thd, Event_parse_data *parse_data, bool if_exists,
uint *rows_affected);
int
......@@ -83,7 +83,7 @@ public:
uint *rows_affected);
int
drop_event(THD *thd, sp_name *name, bool drop_if_exists, uint *rows_affected);
drop_event(THD *thd, sp_name *name, bool if_exists, uint *rows_affected);
int
drop_schema_events(THD *thd, char *db);
......@@ -105,9 +105,9 @@ public:
int
dump_internal_status(THD *thd);
Event_db_repository *db_repository;
Event_queue *event_queue;
Event_scheduler_ng *scheduler_ng;
Event_db_repository *db_repository;
private:
/* Singleton DP is used */
......
sql/set_var.cc
View file @ b9a7fe27
......@@ -57,7 +57,6 @@
#include <myisam.h>
#include <my_dir.h>
#include "event_scheduler.h"
#include "events.h"
/* WITH_BERKELEY_STORAGE_ENGINE */
......@@ -3894,7 +3893,6 @@ bool
sys_var_event_scheduler::update(THD *thd, set_var *var)
{
int res;
Event_scheduler *scheduler= Event_scheduler::get_instance();
/* here start the thread if not running. */
DBUG_ENTER("sys_var_event_scheduler::update");
if (Events::opt_event_scheduler == 0)
......@@ -3927,8 +3925,6 @@ sys_var_event_scheduler::update(THD *thd, set_var *var)
byte *sys_var_event_scheduler::value_ptr(THD *thd, enum_var_type type,
LEX_STRING *base)
{
Event_scheduler *scheduler= Event_scheduler::get_instance();
if (Events::opt_event_scheduler == 0)
thd->sys_var_tmp.long_value= 0;
else if (Events::get_instance()->is_started())
......
sql/sql_parse.cc
View file @ b9a7fe27
......@@ -3832,25 +3832,26 @@ end_with_restore_list:
case SQLCOM_CREATE_EVENT:
case SQLCOM_ALTER_EVENT:
{
uint rows_affected= 1;
uint affected= 1;
DBUG_ASSERT(lex->event_parse_data);
switch (lex->sql_command) {
case SQLCOM_CREATE_EVENT:
res= Events::get_instance()->create_event(thd, lex->event_parse_data,
(uint) lex->create_info.options,
&rows_affected);
res= Events::get_instance()->
create_event(thd, lex->event_parse_data,
lex->create_info.options & HA_LEX_CREATE_IF_NOT_EXISTS,
&affected);
break;
case SQLCOM_ALTER_EVENT:
res= Events::get_instance()->update_event(thd, lex->event_parse_data,
lex->spname, &rows_affected);
res= Events::get_instance()->
update_event(thd, lex->event_parse_data, lex->spname, &affected);
break;
default:;
}
DBUG_PRINT("info", ("CREATE/ALTER/DROP returned error code=%d af_rows=%d",
res, rows_affected));
DBUG_PRINT("info",("DDL error code=%d affected=%d", res, affected));
if (!res)
send_ok(thd, rows_affected);
send_ok(thd, affected);
/* Don't do it, if we are inside a SP */
if (!thd->spcont)
{
delete lex->sphead;
......@@ -3867,8 +3868,7 @@ end_with_restore_list:
if (! lex->spname->m_db.str)
{
my_message(ER_NO_DB_ERROR, ER(ER_NO_DB_ERROR), MYF(0));
res= true;
break;
goto error;
}
if (check_access(thd, EVENT_ACL, lex->spname->m_db.str, 0, 0, 0,
is_schema_db(lex->spname->m_db.str)))
......@@ -3885,11 +3885,10 @@ end_with_restore_list:
res= Events::get_instance()->show_create_event(thd, lex->spname);
else
{
uint rows_affected= 1;
if (!(res= Events::get_instance()->drop_event(thd, lex->spname,
lex->drop_if_exists,
&rows_affected)))
send_ok(thd, rows_affected);
uint affected= 1;
if (!(res= Events::get_instance()->
drop_event(thd, lex->spname, lex->drop_if_exists, &affected)))
send_ok(thd, affected);
}
break;
}
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment
GitLab Nexedi Edition | About GitLab | About Nexedi | 沪ICP备2021021310号-2 | 沪ICP备2021021310号-7