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	 f5fdf3e87a
			
		
	
	f5fdf3e87a
	
	
	
		
			
			- CHAR() now returns binary string as default - CHAR(X*65536+Y*256+Z) is now equal to CHAR(X,Y,Z) independent of the character set for CHAR() - Test for both ETIMEDOUT and ETIME from pthread_cond_timedwait() (Some old systems returns ETIME and it's safer to test for both values than to try to write a wrapper for each old system) - Fixed new introduced bug in NOT BETWEEN X and X - Ensure we call commit_by_xid or rollback_by_xid for all engines, even if one engine has failed - Use octet2hex() for all conversion of string to hex - Simplify and optimize code
		
			
				
	
	
		
			1484 lines
		
	
	
		
			44 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			1484 lines
		
	
	
		
			44 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* Copyright (C) 2000 MySQL AB
 | |
| 
 | |
|    This program is free software; you can redistribute it and/or modify
 | |
|    it under the terms of the GNU General Public License as published by
 | |
|    the Free Software Foundation; either version 2 of the License, or
 | |
|    (at your option) any later version.
 | |
| 
 | |
|    This program is distributed in the hope that it will be useful,
 | |
|    but WITHOUT ANY WARRANTY; without even the implied warranty of
 | |
|    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 | |
|    GNU General Public License for more details.
 | |
| 
 | |
|    You should have received a copy of the GNU General Public License
 | |
|    along with this program; if not, write to the Free Software
 | |
|    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
 | |
| 
 | |
| /*
 | |
| Read and write locks for Posix threads. All tread must acquire
 | |
| all locks it needs through thr_multi_lock() to avoid dead-locks.
 | |
| A lock consists of a master lock (THR_LOCK), and lock instances
 | |
| (THR_LOCK_DATA).
 | |
| Any thread can have any number of lock instances (read and write:s) on
 | |
| any lock. All lock instances must be freed.
 | |
| Locks are prioritized according to:
 | |
| 
 | |
| The current lock types are:
 | |
| 
 | |
| TL_READ	 		# Low priority read
 | |
| TL_READ_WITH_SHARED_LOCKS
 | |
| TL_READ_HIGH_PRIORITY	# High priority read
 | |
| TL_READ_NO_INSERT	# Read without concurrent inserts
 | |
| TL_WRITE_ALLOW_WRITE	# Write lock that allows other writers
 | |
| TL_WRITE_ALLOW_READ	# Write lock, but allow reading
 | |
| TL_WRITE_CONCURRENT_INSERT
 | |
| 			# Insert that can be mixed when selects
 | |
| TL_WRITE_DELAYED	# Used by delayed insert
 | |
| 			# Allows lower locks to take over
 | |
| TL_WRITE_LOW_PRIORITY	# Low priority write
 | |
| TL_WRITE		# High priority write
 | |
| TL_WRITE_ONLY		# High priority write
 | |
| 			# Abort all new lock request with an error
 | |
| 
 | |
| Locks are prioritized according to:
 | |
| 
 | |
| WRITE_ALLOW_WRITE, WRITE_ALLOW_READ, WRITE_CONCURRENT_INSERT, WRITE_DELAYED,
 | |
| WRITE_LOW_PRIORITY, READ, WRITE, READ_HIGH_PRIORITY and WRITE_ONLY
 | |
| 
 | |
| Locks in the same privilege level are scheduled in first-in-first-out order.
 | |
| 
 | |
| To allow concurrent read/writes locks, with 'WRITE_CONCURRENT_INSERT' one
 | |
| should put a pointer to the following functions in the lock structure:
 | |
| (If the pointer is zero (default), the function is not called)
 | |
| 
 | |
| check_status:
 | |
| 	 Before giving a lock of type TL_WRITE_CONCURRENT_INSERT,
 | |
|          we check if this function exists and returns 0.
 | |
| 	 If not, then the lock is upgraded to TL_WRITE_LOCK
 | |
| 	 In MyISAM this is a simple check if the insert can be done
 | |
| 	 at the end of the datafile.
 | |
| update_status:
 | |
| 	Before a write lock is released, this function is called.
 | |
| 	In MyISAM this functions updates the count and length of the datafile
 | |
| get_status:
 | |
| 	When one gets a lock this functions is called.
 | |
| 	In MyISAM this stores the number of rows and size of the datafile
 | |
| 	for concurrent reads.
 | |
| 
 | |
| The lock algorithm allows one to have one TL_WRITE_ALLOW_READ,
 | |
| TL_WRITE_CONCURRENT_INSERT or one TL_WRITE_DELAYED lock at the same time as
 | |
| multiple read locks.
 | |
| 
 | |
| */
 | |
| 
 | |
| #if !defined(MAIN) && !defined(DBUG_OFF) && !defined(EXTRA_DEBUG)
 | |
| #define DBUG_OFF
 | |
| #endif
 | |
| 
 | |
| #include "mysys_priv.h"
 | |
| 
 | |
| #ifdef THREAD
 | |
| #include "thr_lock.h"
 | |
| #include <m_string.h>
 | |
| #include <errno.h>
 | |
| 
 | |
| my_bool thr_lock_inited=0;
 | |
| ulong locks_immediate = 0L, locks_waited = 0L;
 | |
| ulong table_lock_wait_timeout;
 | |
| enum thr_lock_type thr_upgraded_concurrent_insert_lock = TL_WRITE;
 | |
| 
 | |
| /* The following constants are only for debug output */
 | |
| #define MAX_THREADS 100
 | |
| #define MAX_LOCKS   100
 | |
| 
 | |
| 
 | |
| LIST *thr_lock_thread_list;			/* List of threads in use */
 | |
| ulong max_write_lock_count= ~(ulong) 0L;
 | |
| 
 | |
| static inline pthread_cond_t *get_cond(void)
 | |
| {
 | |
|   return &my_thread_var->suspend;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** For the future (now the thread specific cond is alloced by my_pthread.c)
 | |
| */
 | |
| 
 | |
| my_bool init_thr_lock()
 | |
| {
 | |
|   thr_lock_inited=1;
 | |
|   return 0;
 | |
| }
 | |
| 
 | |
| static inline my_bool
 | |
| thr_lock_owner_equal(THR_LOCK_OWNER *rhs, THR_LOCK_OWNER *lhs)
 | |
| {
 | |
|   return rhs == lhs;
 | |
| }
 | |
| 
 | |
| 
 | |
| #ifdef EXTRA_DEBUG
 | |
| #define MAX_FOUND_ERRORS	10		/* Report 10 first errors */
 | |
| static uint found_errors=0;
 | |
| 
 | |
| static int check_lock(struct st_lock_list *list, const char* lock_type,
 | |
| 		      const char *where, my_bool same_owner, bool no_cond)
 | |
| {
 | |
|   THR_LOCK_DATA *data,**prev;
 | |
|   uint count=0;
 | |
|   THR_LOCK_OWNER *first_owner;
 | |
|   LINT_INIT(first_owner);
 | |
| 
 | |
|   prev= &list->data;
 | |
|   if (list->data)
 | |
|   {
 | |
|     enum thr_lock_type last_lock_type=list->data->type;
 | |
| 
 | |
|     if (same_owner && list->data)
 | |
|       first_owner= list->data->owner;
 | |
|     for (data=list->data; data && count++ < MAX_LOCKS ; data=data->next)
 | |
|     {
 | |
|       if (data->type != last_lock_type)
 | |
| 	last_lock_type=TL_IGNORE;
 | |
|       if (data->prev != prev)
 | |
|       {
 | |
| 	fprintf(stderr,
 | |
| 		"Warning: prev link %d didn't point at previous lock at %s: %s\n",
 | |
| 		count, lock_type, where);
 | |
| 	return 1;
 | |
|       }
 | |
|       if (same_owner &&
 | |
|           !thr_lock_owner_equal(data->owner, first_owner) &&
 | |
| 	  last_lock_type != TL_WRITE_ALLOW_WRITE)
 | |
|       {
 | |
| 	fprintf(stderr,
 | |
| 		"Warning: Found locks from different threads in %s: %s\n",
 | |
| 		lock_type,where);
 | |
| 	return 1;
 | |
|       }
 | |
|       if (no_cond && data->cond)
 | |
|       {
 | |
| 	fprintf(stderr,
 | |
| 		"Warning: Found active lock with not reset cond %s: %s\n",
 | |
| 		lock_type,where);
 | |
| 	return 1;
 | |
|       }
 | |
|       prev= &data->next;
 | |
|     }
 | |
|     if (data)
 | |
|     {
 | |
|       fprintf(stderr,"Warning: found too many locks at %s: %s\n",
 | |
| 	      lock_type,where);
 | |
|       return 1;
 | |
|     }
 | |
|   }
 | |
|   if (prev != list->last)
 | |
|   {
 | |
|     fprintf(stderr,"Warning: last didn't point at last lock at %s: %s\n",
 | |
| 	    lock_type, where);
 | |
|     return 1;
 | |
|   }
 | |
|   return 0;
 | |
| }
 | |
| 
 | |
| 
 | |
| static void check_locks(THR_LOCK *lock, const char *where,
 | |
| 			my_bool allow_no_locks)
 | |
| {
 | |
|   uint old_found_errors=found_errors;
 | |
|   DBUG_ENTER("check_locks");
 | |
| 
 | |
|   if (found_errors < MAX_FOUND_ERRORS)
 | |
|   {
 | |
|     if (check_lock(&lock->write,"write",where,1,1) |
 | |
| 	check_lock(&lock->write_wait,"write_wait",where,0,0) |
 | |
| 	check_lock(&lock->read,"read",where,0,1) |
 | |
| 	check_lock(&lock->read_wait,"read_wait",where,0,0))
 | |
|       found_errors++;
 | |
| 
 | |
|     if (found_errors < MAX_FOUND_ERRORS)
 | |
|     {
 | |
|       uint count=0;
 | |
|       THR_LOCK_DATA *data;
 | |
|       for (data=lock->read.data ; data ; data=data->next)
 | |
|       {
 | |
| 	if ((int) data->type == (int) TL_READ_NO_INSERT)
 | |
| 	  count++;
 | |
|       }
 | |
|       if (count != lock->read_no_write_count)
 | |
|       {
 | |
| 	found_errors++;
 | |
| 	fprintf(stderr,
 | |
| 		"Warning at '%s': Locks read_no_write_count was %u when it should have been %u\n", where, lock->read_no_write_count,count);
 | |
|       }      
 | |
| 
 | |
|       if (!lock->write.data)
 | |
|       {
 | |
| 	if (!allow_no_locks && !lock->read.data &&
 | |
| 	    (lock->write_wait.data || lock->read_wait.data))
 | |
| 	{
 | |
| 	  found_errors++;
 | |
| 	  fprintf(stderr,
 | |
| 		  "Warning at '%s': No locks in use but locks are in wait queue\n",
 | |
| 		  where);
 | |
| 	}
 | |
| 	if (!lock->write_wait.data)
 | |
| 	{
 | |
| 	  if (!allow_no_locks && lock->read_wait.data)
 | |
| 	  {
 | |
| 	    found_errors++;
 | |
| 	    fprintf(stderr,
 | |
| 		    "Warning at '%s': No write locks and waiting read locks\n",
 | |
| 		    where);
 | |
| 	  }
 | |
| 	}
 | |
| 	else
 | |
| 	{
 | |
| 	  if (!allow_no_locks &&
 | |
| 	      (((lock->write_wait.data->type == TL_WRITE_CONCURRENT_INSERT ||
 | |
| 		 lock->write_wait.data->type == TL_WRITE_ALLOW_WRITE) &&
 | |
| 		!lock->read_no_write_count) ||
 | |
| 	       lock->write_wait.data->type == TL_WRITE_ALLOW_READ ||
 | |
| 	       (lock->write_wait.data->type == TL_WRITE_DELAYED &&
 | |
| 		!lock->read.data)))
 | |
| 	  {
 | |
| 	    found_errors++;
 | |
| 	    fprintf(stderr,
 | |
| 		    "Warning at '%s': Write lock %d waiting while no exclusive read locks\n",where,(int) lock->write_wait.data->type);
 | |
| 	  }
 | |
| 	}	      
 | |
|       }
 | |
|       else
 | |
|       {						/* Have write lock */
 | |
| 	if (lock->write_wait.data)
 | |
| 	{
 | |
| 	  if (!allow_no_locks && 
 | |
| 	      lock->write.data->type == TL_WRITE_ALLOW_WRITE &&
 | |
| 	      lock->write_wait.data->type == TL_WRITE_ALLOW_WRITE)
 | |
| 	  {
 | |
| 	    found_errors++;
 | |
| 	    fprintf(stderr,
 | |
| 		    "Warning at '%s': Found WRITE_ALLOW_WRITE lock waiting for WRITE_ALLOW_WRITE lock\n",
 | |
| 		    where);
 | |
| 	  }
 | |
| 	}
 | |
| 	if (lock->read.data)
 | |
| 	{
 | |
|           if (!thr_lock_owner_equal(lock->write.data->owner,
 | |
|                                     lock->read.data->owner) &&
 | |
| 	      ((lock->write.data->type > TL_WRITE_DELAYED &&
 | |
| 		lock->write.data->type != TL_WRITE_ONLY) ||
 | |
| 	       ((lock->write.data->type == TL_WRITE_CONCURRENT_INSERT ||
 | |
| 		 lock->write.data->type == TL_WRITE_ALLOW_WRITE) &&
 | |
| 		lock->read_no_write_count)))
 | |
| 	  {
 | |
| 	    found_errors++;
 | |
| 	    fprintf(stderr,
 | |
| 		    "Warning at '%s': Found lock of type %d that is write and read locked\n",
 | |
| 		    where, lock->write.data->type);
 | |
| 	    DBUG_PRINT("warning",("At '%s': Found lock of type %d that is write and read locked\n",
 | |
| 		    where, lock->write.data->type));
 | |
| 
 | |
| 	  }
 | |
| 	}
 | |
| 	if (lock->read_wait.data)
 | |
| 	{
 | |
| 	  if (!allow_no_locks && lock->write.data->type <= TL_WRITE_DELAYED &&
 | |
| 	      lock->read_wait.data->type <= TL_READ_HIGH_PRIORITY)
 | |
| 	  {
 | |
| 	    found_errors++;
 | |
| 	    fprintf(stderr,
 | |
| 		    "Warning at '%s': Found read lock of type %d waiting for write lock of type %d\n",
 | |
| 		    where,
 | |
| 		    (int) lock->read_wait.data->type,
 | |
| 		    (int) lock->write.data->type);
 | |
| 	  }
 | |
| 	}
 | |
|       }
 | |
|     }
 | |
|     if (found_errors != old_found_errors)
 | |
|     {
 | |
|       DBUG_PRINT("error",("Found wrong lock"));
 | |
|     }
 | |
|   }
 | |
|   DBUG_VOID_RETURN;
 | |
| }
 | |
| 
 | |
| #else /* EXTRA_DEBUG */
 | |
| #define check_locks(A,B,C)
 | |
| #endif
 | |
| 
 | |
| 
 | |
| 	/* Initialize a lock */
 | |
| 
 | |
| void thr_lock_init(THR_LOCK *lock)
 | |
| {
 | |
|   DBUG_ENTER("thr_lock_init");
 | |
|   bzero((char*) lock,sizeof(*lock));
 | |
|   VOID(pthread_mutex_init(&lock->mutex,MY_MUTEX_INIT_FAST));
 | |
|   lock->read.last= &lock->read.data;
 | |
|   lock->read_wait.last= &lock->read_wait.data;
 | |
|   lock->write_wait.last= &lock->write_wait.data;
 | |
|   lock->write.last= &lock->write.data;
 | |
| 
 | |
|   pthread_mutex_lock(&THR_LOCK_lock);		/* Add to locks in use */
 | |
|   lock->list.data=(void*) lock;
 | |
|   thr_lock_thread_list=list_add(thr_lock_thread_list,&lock->list);
 | |
|   pthread_mutex_unlock(&THR_LOCK_lock);
 | |
|   DBUG_VOID_RETURN;
 | |
| }
 | |
| 
 | |
| 
 | |
| void thr_lock_delete(THR_LOCK *lock)
 | |
| {
 | |
|   DBUG_ENTER("thr_lock_delete");
 | |
|   VOID(pthread_mutex_destroy(&lock->mutex));
 | |
|   pthread_mutex_lock(&THR_LOCK_lock);
 | |
|   thr_lock_thread_list=list_delete(thr_lock_thread_list,&lock->list);
 | |
|   pthread_mutex_unlock(&THR_LOCK_lock);
 | |
|   DBUG_VOID_RETURN;
 | |
| }
 | |
| 
 | |
| 
 | |
| void thr_lock_info_init(THR_LOCK_INFO *info)
 | |
| {
 | |
|   info->thread= pthread_self();
 | |
|   info->thread_id= my_thread_id();              /* for debugging */
 | |
|   info->n_cursors= 0;
 | |
| }
 | |
| 
 | |
| 	/* Initialize a lock instance */
 | |
| 
 | |
| void thr_lock_data_init(THR_LOCK *lock,THR_LOCK_DATA *data, void *param)
 | |
| {
 | |
|   data->lock=lock;
 | |
|   data->type=TL_UNLOCK;
 | |
|   data->owner= 0;                               /* no owner yet */
 | |
|   data->status_param=param;
 | |
|   data->cond=0;
 | |
| }
 | |
| 
 | |
| 
 | |
| static inline my_bool
 | |
| have_old_read_lock(THR_LOCK_DATA *data, THR_LOCK_OWNER *owner)
 | |
| {
 | |
|   for ( ; data ; data=data->next)
 | |
|   {
 | |
|     if (thr_lock_owner_equal(data->owner, owner))
 | |
|       return 1;					/* Already locked by thread */
 | |
|   }
 | |
|   return 0;
 | |
| }
 | |
| 
 | |
| static inline my_bool have_specific_lock(THR_LOCK_DATA *data,
 | |
| 					 enum thr_lock_type type)
 | |
| {
 | |
|   for ( ; data ; data=data->next)
 | |
|   {
 | |
|     if (data->type == type)
 | |
|       return 1;
 | |
|   }
 | |
|   return 0;
 | |
| }
 | |
| 
 | |
| 
 | |
| static enum enum_thr_lock_result
 | |
| wait_for_lock(struct st_lock_list *wait, THR_LOCK_DATA *data,
 | |
|               my_bool in_wait_list)
 | |
| {
 | |
|   struct st_my_thread_var *thread_var= my_thread_var;
 | |
|   pthread_cond_t *cond= &thread_var->suspend;
 | |
|   struct timespec wait_timeout;
 | |
|   enum enum_thr_lock_result result= THR_LOCK_ABORTED;
 | |
|   my_bool can_deadlock= test(data->owner->info->n_cursors);
 | |
| 
 | |
|   if (!in_wait_list)
 | |
|   {
 | |
|     (*wait->last)=data;				/* Wait for lock */
 | |
|     data->prev= wait->last;
 | |
|     wait->last= &data->next;
 | |
|   }
 | |
| 
 | |
|   /* Set up control struct to allow others to abort locks */
 | |
|   thread_var->current_mutex= &data->lock->mutex;
 | |
|   thread_var->current_cond=  cond;
 | |
|   data->cond= cond;
 | |
| 
 | |
|   if (can_deadlock)
 | |
|     set_timespec(wait_timeout, table_lock_wait_timeout);
 | |
|   while (!thread_var->abort || in_wait_list)
 | |
|   {
 | |
|     int rc= (can_deadlock ?
 | |
|              pthread_cond_timedwait(cond, &data->lock->mutex,
 | |
|                                     &wait_timeout) :
 | |
|              pthread_cond_wait(cond, &data->lock->mutex));
 | |
|     /*
 | |
|       We must break the wait if one of the following occurs:
 | |
|       - the connection has been aborted (!thread_var->abort), but
 | |
|         this is not a delayed insert thread (in_wait_list). For a delayed
 | |
|         insert thread the proper action at shutdown is, apparently, to
 | |
|         acquire the lock and complete the insert.
 | |
|       - the lock has been granted (data->cond is set to NULL by the granter),
 | |
|         or the waiting has been aborted (additionally data->type is set to
 | |
|         TL_UNLOCK).
 | |
|       - the wait has timed out (rc == ETIMEDOUT)
 | |
|       Order of checks below is important to not report about timeout
 | |
|       if the predicate is true.
 | |
|     */
 | |
|     if (data->cond == 0)
 | |
|       break;
 | |
|     if (rc == ETIMEDOUT || rc == ETIME)
 | |
|     {
 | |
|       result= THR_LOCK_WAIT_TIMEOUT;
 | |
|       break;
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   if (data->cond || data->type == TL_UNLOCK)
 | |
|   {
 | |
|     if (data->cond)                             /* aborted or timed out */
 | |
|     {
 | |
|       if (((*data->prev)=data->next))		/* remove from wait-list */
 | |
| 	data->next->prev= data->prev;
 | |
|       else
 | |
| 	wait->last=data->prev;
 | |
|       data->type= TL_UNLOCK;                    /* No lock */
 | |
|     }
 | |
|     check_locks(data->lock,"failed wait_for_lock",0);
 | |
|   }
 | |
|   else
 | |
|   {
 | |
|     result= THR_LOCK_SUCCESS;
 | |
|     statistic_increment(locks_waited, &THR_LOCK_lock);
 | |
|     if (data->lock->get_status)
 | |
|       (*data->lock->get_status)(data->status_param, 0);
 | |
|     check_locks(data->lock,"got wait_for_lock",0);
 | |
|   }
 | |
|   pthread_mutex_unlock(&data->lock->mutex);
 | |
| 
 | |
|   /* The following must be done after unlock of lock->mutex */
 | |
|   pthread_mutex_lock(&thread_var->mutex);
 | |
|   thread_var->current_mutex= 0;
 | |
|   thread_var->current_cond=  0;
 | |
|   pthread_mutex_unlock(&thread_var->mutex);
 | |
|   return result;
 | |
| }
 | |
| 
 | |
| 
 | |
| enum enum_thr_lock_result
 | |
| thr_lock(THR_LOCK_DATA *data, THR_LOCK_OWNER *owner,
 | |
|          enum thr_lock_type lock_type)
 | |
| {
 | |
|   THR_LOCK *lock=data->lock;
 | |
|   enum enum_thr_lock_result result= THR_LOCK_SUCCESS;
 | |
|   struct st_lock_list *wait_queue;
 | |
|   THR_LOCK_DATA *lock_owner;
 | |
|   DBUG_ENTER("thr_lock");
 | |
| 
 | |
|   data->next=0;
 | |
|   data->cond=0;					/* safety */
 | |
|   data->type=lock_type;
 | |
|   data->owner= owner;                           /* Must be reset ! */
 | |
|   VOID(pthread_mutex_lock(&lock->mutex));
 | |
|   DBUG_PRINT("lock",("data: 0x%lx  thread: %ld  lock: 0x%lx  type: %d",
 | |
| 		      data, data->owner->info->thread_id,
 | |
|                       lock, (int) lock_type));
 | |
|   check_locks(lock,(uint) lock_type <= (uint) TL_READ_NO_INSERT ?
 | |
| 	      "enter read_lock" : "enter write_lock",0);
 | |
|   if ((int) lock_type <= (int) TL_READ_NO_INSERT)
 | |
|   {
 | |
|     /* Request for READ lock */
 | |
|     if (lock->write.data)
 | |
|     {
 | |
|       /* We can allow a read lock even if there is already a write lock
 | |
| 	 on the table in one the following cases:
 | |
| 	 - This thread alread have a write lock on the table
 | |
| 	 - The write lock is TL_WRITE_ALLOW_READ or TL_WRITE_DELAYED
 | |
|            and the read lock is TL_READ_HIGH_PRIORITY or TL_READ
 | |
|          - The write lock is TL_WRITE_CONCURRENT_INSERT or TL_WRITE_ALLOW_WRITE
 | |
| 	   and the read lock is not TL_READ_NO_INSERT
 | |
|       */
 | |
| 
 | |
|       DBUG_PRINT("lock",("write locked by thread: %ld",
 | |
| 			 lock->write.data->owner->info->thread_id));
 | |
|       if (thr_lock_owner_equal(data->owner, lock->write.data->owner) ||
 | |
| 	  (lock->write.data->type <= TL_WRITE_DELAYED &&
 | |
| 	   (((int) lock_type <= (int) TL_READ_HIGH_PRIORITY) ||
 | |
| 	    (lock->write.data->type != TL_WRITE_CONCURRENT_INSERT &&
 | |
| 	     lock->write.data->type != TL_WRITE_ALLOW_READ))))
 | |
|       {						/* Already got a write lock */
 | |
| 	(*lock->read.last)=data;		/* Add to running FIFO */
 | |
| 	data->prev=lock->read.last;
 | |
| 	lock->read.last= &data->next;
 | |
| 	if (lock_type == TL_READ_NO_INSERT)
 | |
| 	  lock->read_no_write_count++;
 | |
| 	check_locks(lock,"read lock with old write lock",0);
 | |
| 	if (lock->get_status)
 | |
| 	  (*lock->get_status)(data->status_param, 0);
 | |
| 	statistic_increment(locks_immediate,&THR_LOCK_lock);
 | |
| 	goto end;
 | |
|       }
 | |
|       if (lock->write.data->type == TL_WRITE_ONLY)
 | |
|       {
 | |
| 	/* We are not allowed to get a READ lock in this case */
 | |
| 	data->type=TL_UNLOCK;
 | |
|         result= THR_LOCK_ABORTED;               /* Can't wait for this one */
 | |
| 	goto end;
 | |
|       }
 | |
|     }
 | |
|     else if (!lock->write_wait.data ||
 | |
| 	     lock->write_wait.data->type <= TL_WRITE_LOW_PRIORITY ||
 | |
| 	     lock_type == TL_READ_HIGH_PRIORITY ||
 | |
| 	     have_old_read_lock(lock->read.data, data->owner))
 | |
|     {						/* No important write-locks */
 | |
|       (*lock->read.last)=data;			/* Add to running FIFO */
 | |
|       data->prev=lock->read.last;
 | |
|       lock->read.last= &data->next;
 | |
|       if (lock->get_status)
 | |
| 	(*lock->get_status)(data->status_param, 0);
 | |
|       if (lock_type == TL_READ_NO_INSERT)
 | |
| 	lock->read_no_write_count++;
 | |
|       check_locks(lock,"read lock with no write locks",0);
 | |
|       statistic_increment(locks_immediate,&THR_LOCK_lock);
 | |
|       goto end;
 | |
|     }
 | |
|     /*
 | |
|       We're here if there is an active write lock or no write
 | |
|       lock but a high priority write waiting in the write_wait queue.
 | |
|       In the latter case we should yield the lock to the writer.
 | |
|     */
 | |
|     wait_queue= &lock->read_wait;
 | |
|   }
 | |
|   else						/* Request for WRITE lock */
 | |
|   {
 | |
|     if (lock_type == TL_WRITE_DELAYED)
 | |
|     {
 | |
|       if (lock->write.data && lock->write.data->type == TL_WRITE_ONLY)
 | |
|       {
 | |
| 	data->type=TL_UNLOCK;
 | |
|         result= THR_LOCK_ABORTED;               /* Can't wait for this one */
 | |
| 	goto end;
 | |
|       }
 | |
|       /*
 | |
| 	if there is a TL_WRITE_ALLOW_READ lock, we have to wait for a lock
 | |
| 	(TL_WRITE_ALLOW_READ is used for ALTER TABLE in MySQL)
 | |
|       */
 | |
|       if ((!lock->write.data ||
 | |
| 	   lock->write.data->type != TL_WRITE_ALLOW_READ) &&
 | |
| 	  !have_specific_lock(lock->write_wait.data,TL_WRITE_ALLOW_READ) &&
 | |
| 	  (lock->write.data || lock->read.data))
 | |
|       {
 | |
| 	/* Add delayed write lock to write_wait queue, and return at once */
 | |
| 	(*lock->write_wait.last)=data;
 | |
| 	data->prev=lock->write_wait.last;
 | |
| 	lock->write_wait.last= &data->next;
 | |
| 	data->cond=get_cond();
 | |
|         /*
 | |
|           We don't have to do get_status here as we will do it when we change
 | |
|           the delayed lock to a real write lock
 | |
|         */
 | |
| 	statistic_increment(locks_immediate,&THR_LOCK_lock);
 | |
| 	goto end;
 | |
|       }
 | |
|     }
 | |
|     else if (lock_type == TL_WRITE_CONCURRENT_INSERT && ! lock->check_status)
 | |
|       data->type=lock_type= thr_upgraded_concurrent_insert_lock;
 | |
| 
 | |
|     if (lock->write.data)			/* If there is a write lock */
 | |
|     {
 | |
|       if (lock->write.data->type == TL_WRITE_ONLY)
 | |
|       {
 | |
| 	/* We are not allowed to get a lock in this case */
 | |
| 	data->type=TL_UNLOCK;
 | |
|         result= THR_LOCK_ABORTED;               /* Can't wait for this one */
 | |
| 	goto end;
 | |
|       }
 | |
| 
 | |
|       /*
 | |
| 	The following test will not work if the old lock was a
 | |
| 	TL_WRITE_ALLOW_WRITE, TL_WRITE_ALLOW_READ or TL_WRITE_DELAYED in
 | |
| 	the same thread, but this will never happen within MySQL.
 | |
|       */
 | |
|       if (thr_lock_owner_equal(data->owner, lock->write.data->owner) ||
 | |
| 	  (lock_type == TL_WRITE_ALLOW_WRITE &&
 | |
| 	   !lock->write_wait.data &&
 | |
| 	   lock->write.data->type == TL_WRITE_ALLOW_WRITE))
 | |
|       {
 | |
| 	/*
 | |
|           We have already got a write lock or all locks are
 | |
|           TL_WRITE_ALLOW_WRITE
 | |
|         */
 | |
|         DBUG_PRINT("info", ("write_wait.data: 0x%lx  old_type: %d",
 | |
|                             (ulong) lock->write_wait.data,
 | |
|                             lock->write.data->type));
 | |
| 
 | |
| 	(*lock->write.last)=data;	/* Add to running fifo */
 | |
| 	data->prev=lock->write.last;
 | |
| 	lock->write.last= &data->next;
 | |
| 	check_locks(lock,"second write lock",0);
 | |
| 	if (data->lock->get_status)
 | |
| 	  (*data->lock->get_status)(data->status_param, 0);
 | |
| 	statistic_increment(locks_immediate,&THR_LOCK_lock);
 | |
| 	goto end;
 | |
|       }
 | |
|       DBUG_PRINT("lock",("write locked by thread: %ld",
 | |
| 			 lock->write.data->owner->info->thread_id));
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|       DBUG_PRINT("info", ("write_wait.data: 0x%lx",
 | |
|                           (ulong) lock->write_wait.data));
 | |
|       if (!lock->write_wait.data)
 | |
|       {						/* no scheduled write locks */
 | |
|         my_bool concurrent_insert= 0;
 | |
| 	if (lock_type == TL_WRITE_CONCURRENT_INSERT)
 | |
|         {
 | |
|           concurrent_insert= 1;
 | |
|           if ((*lock->check_status)(data->status_param))
 | |
|           {
 | |
|             concurrent_insert= 0;
 | |
|             data->type=lock_type= thr_upgraded_concurrent_insert_lock;
 | |
|           }
 | |
|         }
 | |
| 
 | |
| 	if (!lock->read.data ||
 | |
| 	    (lock_type <= TL_WRITE_DELAYED &&
 | |
| 	     ((lock_type != TL_WRITE_CONCURRENT_INSERT &&
 | |
| 	       lock_type != TL_WRITE_ALLOW_WRITE) ||
 | |
| 	      !lock->read_no_write_count)))
 | |
| 	{
 | |
| 	  (*lock->write.last)=data;		/* Add as current write lock */
 | |
| 	  data->prev=lock->write.last;
 | |
| 	  lock->write.last= &data->next;
 | |
| 	  if (data->lock->get_status)
 | |
| 	    (*data->lock->get_status)(data->status_param, concurrent_insert);
 | |
| 	  check_locks(lock,"only write lock",0);
 | |
| 	  statistic_increment(locks_immediate,&THR_LOCK_lock);
 | |
| 	  goto end;
 | |
| 	}
 | |
|       }
 | |
|       DBUG_PRINT("lock",("write locked by thread: %ld, type: %ld",
 | |
| 			 lock->read.data->owner->info->thread_id, data->type));
 | |
|     }
 | |
|     wait_queue= &lock->write_wait;
 | |
|   }
 | |
|   /*
 | |
|     Try to detect a trivial deadlock when using cursors: attempt to
 | |
|     lock a table that is already locked by an open cursor within the
 | |
|     same connection. lock_owner can be zero if we succumbed to a high
 | |
|     priority writer in the write_wait queue.
 | |
|   */
 | |
|   lock_owner= lock->read.data ? lock->read.data : lock->write.data;
 | |
|   if (lock_owner && lock_owner->owner->info == owner->info)
 | |
|   {
 | |
|     result= THR_LOCK_DEADLOCK;
 | |
|     goto end;
 | |
|   }
 | |
|   /* Can't get lock yet;  Wait for it */
 | |
|   DBUG_RETURN(wait_for_lock(wait_queue, data, 0));
 | |
| end:
 | |
|   pthread_mutex_unlock(&lock->mutex);
 | |
|   DBUG_RETURN(result);
 | |
| }
 | |
| 
 | |
| 
 | |
| static inline void free_all_read_locks(THR_LOCK *lock,
 | |
| 				       bool using_concurrent_insert)
 | |
| {
 | |
|   THR_LOCK_DATA *data=lock->read_wait.data;
 | |
| 
 | |
|   check_locks(lock,"before freeing read locks",1);
 | |
| 
 | |
|   /* move all locks from read_wait list to read list */
 | |
|   (*lock->read.last)=data;
 | |
|   data->prev=lock->read.last;
 | |
|   lock->read.last=lock->read_wait.last;
 | |
| 
 | |
|   /* Clear read_wait list */
 | |
|   lock->read_wait.last= &lock->read_wait.data;
 | |
| 
 | |
|   do
 | |
|   {
 | |
|     pthread_cond_t *cond=data->cond;
 | |
|     if ((int) data->type == (int) TL_READ_NO_INSERT)
 | |
|     {
 | |
|       if (using_concurrent_insert)
 | |
|       {
 | |
| 	/*
 | |
| 	  We can't free this lock; 
 | |
| 	  Link lock away from read chain back into read_wait chain
 | |
| 	*/
 | |
| 	if (((*data->prev)=data->next))
 | |
| 	  data->next->prev=data->prev;
 | |
| 	else
 | |
| 	  lock->read.last=data->prev;
 | |
| 	*lock->read_wait.last= data;
 | |
| 	data->prev= lock->read_wait.last;
 | |
| 	lock->read_wait.last= &data->next;
 | |
| 	continue;
 | |
|       }
 | |
|       lock->read_no_write_count++;
 | |
|     }      
 | |
|     DBUG_PRINT("lock",("giving read lock to thread: %ld",
 | |
| 		       data->owner->info->thread_id));
 | |
|     data->cond=0;				/* Mark thread free */
 | |
|     VOID(pthread_cond_signal(cond));
 | |
|   } while ((data=data->next));
 | |
|   *lock->read_wait.last=0;
 | |
|   if (!lock->read_wait.data)
 | |
|     lock->write_lock_count=0;
 | |
|   check_locks(lock,"after giving read locks",0);
 | |
| }
 | |
| 
 | |
| 	/* Unlock lock and free next thread on same lock */
 | |
| 
 | |
| void thr_unlock(THR_LOCK_DATA *data)
 | |
| {
 | |
|   THR_LOCK *lock=data->lock;
 | |
|   enum thr_lock_type lock_type=data->type;
 | |
|   DBUG_ENTER("thr_unlock");
 | |
|   DBUG_PRINT("lock",("data: 0x%lx  thread: %ld  lock: 0x%lx",
 | |
| 		     data, data->owner->info->thread_id, lock));
 | |
|   pthread_mutex_lock(&lock->mutex);
 | |
|   check_locks(lock,"start of release lock",0);
 | |
| 
 | |
|   if (((*data->prev)=data->next))		/* remove from lock-list */
 | |
|     data->next->prev= data->prev;
 | |
|   else if (lock_type <= TL_READ_NO_INSERT)
 | |
|     lock->read.last=data->prev;
 | |
|   else if (lock_type == TL_WRITE_DELAYED && data->cond)
 | |
|   {
 | |
|     /*
 | |
|       This only happens in extreme circumstances when a 
 | |
|       write delayed lock that is waiting for a lock
 | |
|     */
 | |
|     lock->write_wait.last=data->prev;		/* Put it on wait queue */
 | |
|   }
 | |
|   else
 | |
|     lock->write.last=data->prev;
 | |
|   if (lock_type >= TL_WRITE_CONCURRENT_INSERT && lock->update_status)
 | |
|     (*lock->update_status)(data->status_param);
 | |
|   if (lock_type == TL_READ_NO_INSERT)
 | |
|     lock->read_no_write_count--;
 | |
|   data->type=TL_UNLOCK;				/* Mark unlocked */
 | |
|   check_locks(lock,"after releasing lock",1);
 | |
| 
 | |
|   if (!lock->write.data)			/* If no active write locks */
 | |
|   {
 | |
|     data=lock->write_wait.data;
 | |
|     if (!lock->read.data)			/* If no more locks in use */
 | |
|     {
 | |
|       /* Release write-locks with TL_WRITE or TL_WRITE_ONLY priority first */
 | |
|       if (data &&
 | |
| 	  (data->type != TL_WRITE_LOW_PRIORITY || !lock->read_wait.data ||
 | |
| 	   lock->read_wait.data->type < TL_READ_HIGH_PRIORITY))
 | |
|       {
 | |
| 	if (lock->write_lock_count++ > max_write_lock_count)
 | |
| 	{
 | |
| 	  /* Too many write locks in a row;  Release all waiting read locks */
 | |
| 	  lock->write_lock_count=0;
 | |
| 	  if (lock->read_wait.data)
 | |
| 	  {
 | |
| 	    DBUG_PRINT("info",("Freeing all read_locks because of max_write_lock_count"));
 | |
| 	    free_all_read_locks(lock,0);
 | |
| 	    goto end;
 | |
| 	  }
 | |
| 	}
 | |
| 	for (;;)
 | |
| 	{
 | |
| 	  if (((*data->prev)=data->next))	/* remove from wait-list */
 | |
| 	    data->next->prev= data->prev;
 | |
| 	  else
 | |
| 	    lock->write_wait.last=data->prev;
 | |
| 	  (*lock->write.last)=data;		/* Put in execute list */
 | |
| 	  data->prev=lock->write.last;
 | |
| 	  data->next=0;
 | |
| 	  lock->write.last= &data->next;
 | |
| 	  if (data->type == TL_WRITE_CONCURRENT_INSERT &&
 | |
| 	      (*lock->check_status)(data->status_param))
 | |
| 	    data->type=TL_WRITE;			/* Upgrade lock */
 | |
| 	  DBUG_PRINT("lock",("giving write lock of type %d to thread: %ld",
 | |
| 			     data->type, data->owner->info->thread_id));
 | |
| 	  {
 | |
| 	    pthread_cond_t *cond=data->cond;
 | |
| 	    data->cond=0;				/* Mark thread free */
 | |
| 	    VOID(pthread_cond_signal(cond));	/* Start waiting thread */
 | |
| 	  }
 | |
| 	  if (data->type != TL_WRITE_ALLOW_WRITE ||
 | |
| 	      !lock->write_wait.data ||
 | |
| 	      lock->write_wait.data->type != TL_WRITE_ALLOW_WRITE)
 | |
| 	    break;
 | |
| 	  data=lock->write_wait.data;		/* Free this too */
 | |
| 	}
 | |
| 	if (data->type >= TL_WRITE_LOW_PRIORITY)
 | |
| 	{
 | |
| 	  check_locks(lock,"giving write lock",0);
 | |
| 	  pthread_mutex_unlock(&lock->mutex);
 | |
| 	  DBUG_VOID_RETURN;
 | |
| 	}
 | |
| 	/* Release possible read locks together with the write lock */
 | |
|       }
 | |
|       if (lock->read_wait.data)
 | |
| 	free_all_read_locks(lock,
 | |
| 			    data &&
 | |
| 			    (data->type == TL_WRITE_CONCURRENT_INSERT ||
 | |
| 			     data->type == TL_WRITE_ALLOW_WRITE));
 | |
|       else
 | |
|       {
 | |
| 	DBUG_PRINT("lock",("No waiting read locks to free"));
 | |
|       }
 | |
|     }
 | |
|     else if (data &&
 | |
| 	     (lock_type=data->type) <= TL_WRITE_DELAYED &&
 | |
| 	     ((lock_type != TL_WRITE_CONCURRENT_INSERT &&
 | |
| 	       lock_type != TL_WRITE_ALLOW_WRITE) ||
 | |
| 	      !lock->read_no_write_count))
 | |
|     {
 | |
|       /*
 | |
| 	For DELAYED, ALLOW_READ, WRITE_ALLOW_WRITE or CONCURRENT_INSERT locks
 | |
| 	start WRITE locks together with the READ locks
 | |
|       */
 | |
|       if (lock_type == TL_WRITE_CONCURRENT_INSERT &&
 | |
| 	  (*lock->check_status)(data->status_param))
 | |
|       {
 | |
| 	data->type=TL_WRITE;			/* Upgrade lock */
 | |
| 	if (lock->read_wait.data)
 | |
| 	  free_all_read_locks(lock,0);
 | |
| 	goto end;
 | |
|       }
 | |
|       do {
 | |
| 	pthread_cond_t *cond=data->cond;
 | |
| 	if (((*data->prev)=data->next))		/* remove from wait-list */
 | |
| 	  data->next->prev= data->prev;
 | |
| 	else
 | |
| 	  lock->write_wait.last=data->prev;
 | |
| 	(*lock->write.last)=data;		/* Put in execute list */
 | |
| 	data->prev=lock->write.last;
 | |
| 	lock->write.last= &data->next;
 | |
| 	data->next=0;				/* Only one write lock */
 | |
| 	data->cond=0;				/* Mark thread free */
 | |
| 	VOID(pthread_cond_signal(cond));	/* Start waiting thread */
 | |
|       } while (lock_type == TL_WRITE_ALLOW_WRITE &&
 | |
| 	       (data=lock->write_wait.data) &&
 | |
| 	       data->type == TL_WRITE_ALLOW_WRITE);
 | |
|       if (lock->read_wait.data)
 | |
| 	free_all_read_locks(lock,
 | |
| 			    (lock_type == TL_WRITE_CONCURRENT_INSERT ||
 | |
| 			     lock_type == TL_WRITE_ALLOW_WRITE));
 | |
|     }
 | |
|     else if (!data && lock->read_wait.data)
 | |
|       free_all_read_locks(lock,0);
 | |
|   }
 | |
| end:
 | |
|   check_locks(lock,"thr_unlock",0);
 | |
|   pthread_mutex_unlock(&lock->mutex);
 | |
|   DBUG_VOID_RETURN;
 | |
| }
 | |
| 
 | |
| 
 | |
| /*
 | |
| ** Get all locks in a specific order to avoid dead-locks
 | |
| ** Sort acording to lock position and put write_locks before read_locks if
 | |
| ** lock on same lock.
 | |
| */
 | |
| 
 | |
| 
 | |
| #define LOCK_CMP(A,B) ((byte*) (A->lock) - (uint) ((A)->type) < (byte*) (B->lock)- (uint) ((B)->type))
 | |
| 
 | |
| static void sort_locks(THR_LOCK_DATA **data,uint count)
 | |
| {
 | |
|   THR_LOCK_DATA **pos,**end,**prev,*tmp;
 | |
| 
 | |
|   /* Sort locks with insertion sort (fast because almost always few locks) */
 | |
| 
 | |
|   for (pos=data+1,end=data+count; pos < end ; pos++)
 | |
|   {
 | |
|     tmp= *pos;
 | |
|     if (LOCK_CMP(tmp,pos[-1]))
 | |
|     {
 | |
|       prev=pos;
 | |
|       do {
 | |
| 	prev[0]=prev[-1];
 | |
|       } while (--prev != data && LOCK_CMP(tmp,prev[-1]));
 | |
|       prev[0]=tmp;
 | |
|     }
 | |
|   }
 | |
| }
 | |
| 
 | |
| 
 | |
| enum enum_thr_lock_result
 | |
| thr_multi_lock(THR_LOCK_DATA **data, uint count, THR_LOCK_OWNER *owner)
 | |
| {
 | |
|   THR_LOCK_DATA **pos,**end;
 | |
|   DBUG_ENTER("thr_multi_lock");
 | |
|   DBUG_PRINT("lock",("data: 0x%lx  count: %d",data,count));
 | |
|   if (count > 1)
 | |
|     sort_locks(data,count);
 | |
|   /* lock everything */
 | |
|   for (pos=data,end=data+count; pos < end ; pos++)
 | |
|   {
 | |
|     enum enum_thr_lock_result result= thr_lock(*pos, owner, (*pos)->type);
 | |
|     if (result != THR_LOCK_SUCCESS)
 | |
|     {						/* Aborted */
 | |
|       thr_multi_unlock(data,(uint) (pos-data));
 | |
|       DBUG_RETURN(result);
 | |
|     }
 | |
| #ifdef MAIN
 | |
|     printf("Thread: %s  Got lock: 0x%lx  type: %d\n",my_thread_name(),
 | |
| 	   (long) pos[0]->lock, pos[0]->type); fflush(stdout);
 | |
| #endif
 | |
|   }
 | |
|   /*
 | |
|     Ensure that all get_locks() have the same status
 | |
|     If we lock the same table multiple times, we must use the same
 | |
|     status_param!
 | |
|   */
 | |
| #if !defined(DONT_USE_RW_LOCKS)
 | |
|   if (count > 1)
 | |
|   {
 | |
|     THR_LOCK_DATA *last_lock= end[-1];
 | |
|     pos=end-1;
 | |
|     do
 | |
|     {
 | |
|       pos--;
 | |
|       if (last_lock->lock == (*pos)->lock &&
 | |
| 	  last_lock->lock->copy_status)
 | |
|       {
 | |
| 	if (last_lock->type <= TL_READ_NO_INSERT)
 | |
| 	{
 | |
| 	  THR_LOCK_DATA **read_lock;
 | |
| 	  /*
 | |
| 	    If we are locking the same table with read locks we must ensure
 | |
| 	    that all tables share the status of the last write lock or
 | |
| 	    the same read lock.
 | |
| 	  */
 | |
| 	  for (;
 | |
| 	       (*pos)->type <= TL_READ_NO_INSERT &&
 | |
| 		 pos != data &&
 | |
| 		 pos[-1]->lock == (*pos)->lock ;
 | |
| 	       pos--) ;
 | |
| 
 | |
| 	  read_lock = pos+1;
 | |
| 	  do
 | |
| 	  {
 | |
| 	    (last_lock->lock->copy_status)((*read_lock)->status_param,
 | |
| 					   (*pos)->status_param);
 | |
| 	  } while (*(read_lock++) != last_lock);
 | |
| 	  last_lock= (*pos);			/* Point at last write lock */
 | |
| 	}
 | |
| 	else
 | |
| 	  (*last_lock->lock->copy_status)((*pos)->status_param,
 | |
| 					  last_lock->status_param);
 | |
|       }
 | |
|       else
 | |
| 	last_lock=(*pos);
 | |
|     } while (pos != data);
 | |
|   }
 | |
| #endif
 | |
|   DBUG_RETURN(THR_LOCK_SUCCESS);
 | |
| }
 | |
| 
 | |
|   /* free all locks */
 | |
| 
 | |
| void thr_multi_unlock(THR_LOCK_DATA **data,uint count)
 | |
| {
 | |
|   THR_LOCK_DATA **pos,**end;
 | |
|   DBUG_ENTER("thr_multi_unlock");
 | |
|   DBUG_PRINT("lock",("data: 0x%lx  count: %d",data,count));
 | |
| 
 | |
|   for (pos=data,end=data+count; pos < end ; pos++)
 | |
|   {
 | |
| #ifdef MAIN
 | |
|     printf("Thread: %s  Rel lock: 0x%lx  type: %d\n",
 | |
| 	   my_thread_name(), (long) pos[0]->lock, pos[0]->type);
 | |
|     fflush(stdout);
 | |
| #endif
 | |
|     if ((*pos)->type != TL_UNLOCK)
 | |
|       thr_unlock(*pos);
 | |
|     else
 | |
|     {
 | |
|       DBUG_PRINT("lock",("Free lock: data: 0x%lx  thread: %ld  lock: 0x%lx",
 | |
| 			 *pos, (*pos)->owner->info->thread_id, (*pos)->lock));
 | |
|     }
 | |
|   }
 | |
|   DBUG_VOID_RETURN;
 | |
| }
 | |
| 
 | |
| /*
 | |
|   Abort all threads waiting for a lock. The lock will be upgraded to
 | |
|   TL_WRITE_ONLY to abort any new accesses to the lock
 | |
| */
 | |
| 
 | |
| void thr_abort_locks(THR_LOCK *lock)
 | |
| {
 | |
|   THR_LOCK_DATA *data;
 | |
|   DBUG_ENTER("thr_abort_locks");
 | |
|   pthread_mutex_lock(&lock->mutex);
 | |
| 
 | |
|   for (data=lock->read_wait.data; data ; data=data->next)
 | |
|   {
 | |
|     data->type=TL_UNLOCK;			/* Mark killed */
 | |
|     /* It's safe to signal the cond first: we're still holding the mutex. */
 | |
|     pthread_cond_signal(data->cond);
 | |
|     data->cond=0;				/* Removed from list */
 | |
|   }
 | |
|   for (data=lock->write_wait.data; data ; data=data->next)
 | |
|   {
 | |
|     data->type=TL_UNLOCK;
 | |
|     pthread_cond_signal(data->cond);
 | |
|     data->cond=0;
 | |
|   }
 | |
|   lock->read_wait.last= &lock->read_wait.data;
 | |
|   lock->write_wait.last= &lock->write_wait.data;
 | |
|   lock->read_wait.data=lock->write_wait.data=0;
 | |
|   if (lock->write.data)
 | |
|     lock->write.data->type=TL_WRITE_ONLY;
 | |
|   pthread_mutex_unlock(&lock->mutex);
 | |
|   DBUG_VOID_RETURN;
 | |
| }
 | |
| 
 | |
| 
 | |
| /*
 | |
|   Abort all locks for specific table/thread combination
 | |
| 
 | |
|   This is used to abort all locks for a specific thread
 | |
| */
 | |
| 
 | |
| my_bool thr_abort_locks_for_thread(THR_LOCK *lock, pthread_t thread)
 | |
| {
 | |
|   THR_LOCK_DATA *data;
 | |
|   my_bool found= FALSE;
 | |
|   DBUG_ENTER("thr_abort_locks_for_thread");
 | |
| 
 | |
|   pthread_mutex_lock(&lock->mutex);
 | |
|   for (data= lock->read_wait.data; data ; data= data->next)
 | |
|   {
 | |
|     if (pthread_equal(thread, data->owner->info->thread))
 | |
|     {
 | |
|       DBUG_PRINT("info",("Aborting read-wait lock"));
 | |
|       data->type= TL_UNLOCK;			/* Mark killed */
 | |
|       /* It's safe to signal the cond first: we're still holding the mutex. */
 | |
|       found= TRUE;
 | |
|       pthread_cond_signal(data->cond);
 | |
|       data->cond= 0;				/* Removed from list */
 | |
| 
 | |
|       if (((*data->prev)= data->next))
 | |
| 	data->next->prev= data->prev;
 | |
|       else
 | |
| 	lock->read_wait.last= data->prev;
 | |
|     }
 | |
|   }
 | |
|   for (data= lock->write_wait.data; data ; data= data->next)
 | |
|   {
 | |
|     if (pthread_equal(thread, data->owner->info->thread))
 | |
|     {
 | |
|       DBUG_PRINT("info",("Aborting write-wait lock"));
 | |
|       data->type= TL_UNLOCK;
 | |
|       found= TRUE;
 | |
|       pthread_cond_signal(data->cond);
 | |
|       data->cond= 0;
 | |
| 
 | |
|       if (((*data->prev)= data->next))
 | |
| 	data->next->prev= data->prev;
 | |
|       else
 | |
| 	lock->write_wait.last= data->prev;
 | |
|     }
 | |
|   }
 | |
|   pthread_mutex_unlock(&lock->mutex);
 | |
|   DBUG_RETURN(found);
 | |
| }
 | |
| 
 | |
| 
 | |
| 
 | |
| /* Upgrade a WRITE_DELAY lock to a WRITE_LOCK */
 | |
| 
 | |
| my_bool thr_upgrade_write_delay_lock(THR_LOCK_DATA *data)
 | |
| {
 | |
|   THR_LOCK *lock=data->lock;
 | |
|   DBUG_ENTER("thr_upgrade_write_delay_lock");
 | |
| 
 | |
|   pthread_mutex_lock(&lock->mutex);
 | |
|   if (data->type == TL_UNLOCK || data->type >= TL_WRITE_LOW_PRIORITY)
 | |
|   {
 | |
|     pthread_mutex_unlock(&lock->mutex);
 | |
|     DBUG_RETURN(data->type == TL_UNLOCK);	/* Test if Aborted */
 | |
|   }
 | |
|   check_locks(lock,"before upgrading lock",0);
 | |
|   /* TODO:  Upgrade to TL_WRITE_CONCURRENT_INSERT in some cases */
 | |
|   data->type=TL_WRITE;				/* Upgrade lock */
 | |
| 
 | |
|   /* Check if someone has given us the lock */
 | |
|   if (!data->cond)
 | |
|   {
 | |
|     if (!lock->read.data)			/* No read locks */
 | |
|     {						/* We have the lock */
 | |
|       if (data->lock->get_status)
 | |
| 	(*data->lock->get_status)(data->status_param, 0);
 | |
|       pthread_mutex_unlock(&lock->mutex);
 | |
|       DBUG_RETURN(0);
 | |
|     }
 | |
| 
 | |
|     if (((*data->prev)=data->next))		/* remove from lock-list */
 | |
|       data->next->prev= data->prev;
 | |
|     else
 | |
|       lock->write.last=data->prev;
 | |
| 
 | |
|     if ((data->next=lock->write_wait.data))	/* Put first in lock_list */
 | |
|       data->next->prev= &data->next;
 | |
|     else
 | |
|       lock->write_wait.last= &data->next;
 | |
|     data->prev= &lock->write_wait.data;
 | |
|     lock->write_wait.data=data;
 | |
|     check_locks(lock,"upgrading lock",0);
 | |
|   }
 | |
|   else
 | |
|   {
 | |
|     check_locks(lock,"waiting for lock",0);
 | |
|   }
 | |
|   DBUG_RETURN(wait_for_lock(&lock->write_wait,data,1));
 | |
| }
 | |
| 
 | |
| 
 | |
| /* downgrade a WRITE lock to a WRITE_DELAY lock if there is pending locks */
 | |
| 
 | |
| my_bool thr_reschedule_write_lock(THR_LOCK_DATA *data)
 | |
| {
 | |
|   THR_LOCK *lock=data->lock;
 | |
|   DBUG_ENTER("thr_reschedule_write_lock");
 | |
| 
 | |
|   pthread_mutex_lock(&lock->mutex);
 | |
|   if (!lock->read_wait.data)			/* No waiting read locks */
 | |
|   {
 | |
|     pthread_mutex_unlock(&lock->mutex);
 | |
|     DBUG_RETURN(0);
 | |
|   }
 | |
| 
 | |
|   data->type=TL_WRITE_DELAYED;
 | |
|   if (lock->update_status)
 | |
|     (*lock->update_status)(data->status_param);
 | |
|   if (((*data->prev)=data->next))		/* remove from lock-list */
 | |
|     data->next->prev= data->prev;
 | |
|   else
 | |
|     lock->write.last=data->prev;
 | |
| 
 | |
|   if ((data->next=lock->write_wait.data))	/* Put first in lock_list */
 | |
|     data->next->prev= &data->next;
 | |
|   else
 | |
|     lock->write_wait.last= &data->next;
 | |
|   data->prev= &lock->write_wait.data;
 | |
|   data->cond=get_cond();			/* This was zero */
 | |
|   lock->write_wait.data=data;
 | |
|   free_all_read_locks(lock,0);
 | |
| 
 | |
|   pthread_mutex_unlock(&lock->mutex);
 | |
|   DBUG_RETURN(thr_upgrade_write_delay_lock(data));
 | |
| }
 | |
| 
 | |
| 
 | |
| #include <my_sys.h>
 | |
| 
 | |
| static void thr_print_lock(const char* name,struct st_lock_list *list)
 | |
| {
 | |
|   THR_LOCK_DATA *data,**prev;
 | |
|   uint count=0;
 | |
| 
 | |
|   if (list->data)
 | |
|   {
 | |
|     printf("%-10s: ",name);
 | |
|     prev= &list->data;
 | |
|     for (data=list->data; data && count++ < MAX_LOCKS ; data=data->next)
 | |
|     {
 | |
|       printf("0x%lx (%lu:%d); ", (ulong) data, data->owner->info->thread_id,
 | |
|              (int) data->type);
 | |
|       if (data->prev != prev)
 | |
| 	printf("\nWarning: prev didn't point at previous lock\n");
 | |
|       prev= &data->next;
 | |
|     }
 | |
|     puts("");
 | |
|     if (prev != list->last)
 | |
|       printf("Warning: last didn't point at last lock\n");
 | |
|   }
 | |
| }
 | |
| 
 | |
| void thr_print_locks(void)
 | |
| {
 | |
|   LIST *list;
 | |
|   uint count=0;
 | |
| 
 | |
|   pthread_mutex_lock(&THR_LOCK_lock);
 | |
|   puts("Current locks:");
 | |
|   for (list= thr_lock_thread_list; list && count++ < MAX_THREADS;
 | |
|        list= list_rest(list))
 | |
|   {
 | |
|     THR_LOCK *lock=(THR_LOCK*) list->data;
 | |
|     VOID(pthread_mutex_lock(&lock->mutex));
 | |
|     printf("lock: 0x%lx:",(ulong) lock);
 | |
|     if ((lock->write_wait.data || lock->read_wait.data) &&
 | |
| 	(! lock->read.data && ! lock->write.data))
 | |
|       printf(" WARNING: ");
 | |
|     if (lock->write.data)
 | |
|       printf(" write");
 | |
|     if (lock->write_wait.data)
 | |
|       printf(" write_wait");
 | |
|     if (lock->read.data)
 | |
|       printf(" read");
 | |
|     if (lock->read_wait.data)
 | |
|       printf(" read_wait");
 | |
|     puts("");
 | |
|     thr_print_lock("write",&lock->write);
 | |
|     thr_print_lock("write_wait",&lock->write_wait);
 | |
|     thr_print_lock("read",&lock->read);
 | |
|     thr_print_lock("read_wait",&lock->read_wait);
 | |
|     VOID(pthread_mutex_unlock(&lock->mutex));
 | |
|     puts("");
 | |
|   }
 | |
|   fflush(stdout);
 | |
|   pthread_mutex_unlock(&THR_LOCK_lock);
 | |
| }
 | |
| 
 | |
| #endif /* THREAD */
 | |
| 
 | |
| /*****************************************************************************
 | |
| ** Test of thread locks
 | |
| ****************************************************************************/
 | |
| 
 | |
| #ifdef MAIN
 | |
| 
 | |
| #ifdef THREAD
 | |
| 
 | |
| struct st_test {
 | |
|   uint lock_nr;
 | |
|   enum thr_lock_type lock_type;
 | |
| };
 | |
| 
 | |
| THR_LOCK locks[5];			/* 4 locks */
 | |
| 
 | |
| struct st_test test_0[] = {{0,TL_READ}};	/* One lock */
 | |
| struct st_test test_1[] = {{0,TL_READ},{0,TL_WRITE}}; /* Read and write lock of lock 0 */
 | |
| struct st_test test_2[] = {{1,TL_WRITE},{0,TL_READ},{2,TL_READ}};
 | |
| struct st_test test_3[] = {{2,TL_WRITE},{1,TL_READ},{0,TL_READ}}; /* Deadlock with test_2 ? */
 | |
| struct st_test test_4[] = {{0,TL_WRITE},{0,TL_READ},{0,TL_WRITE},{0,TL_READ}};
 | |
| struct st_test test_5[] = {{0,TL_READ},{1,TL_READ},{2,TL_READ},{3,TL_READ}}; /* Many reads */
 | |
| struct st_test test_6[] = {{0,TL_WRITE},{1,TL_WRITE},{2,TL_WRITE},{3,TL_WRITE}}; /* Many writes */
 | |
| struct st_test test_7[] = {{3,TL_READ}};
 | |
| struct st_test test_8[] = {{1,TL_READ_NO_INSERT},{2,TL_READ_NO_INSERT},{3,TL_READ_NO_INSERT}};	/* Should be quick */
 | |
| struct st_test test_9[] = {{4,TL_READ_HIGH_PRIORITY}};
 | |
| struct st_test test_10[] ={{4,TL_WRITE}};
 | |
| struct st_test test_11[] = {{0,TL_WRITE_LOW_PRIORITY},{1,TL_WRITE_LOW_PRIORITY},{2,TL_WRITE_LOW_PRIORITY},{3,TL_WRITE_LOW_PRIORITY}}; /* Many writes */
 | |
| struct st_test test_12[] = {{0,TL_WRITE_ALLOW_READ},{1,TL_WRITE_ALLOW_READ},{2,TL_WRITE_ALLOW_READ},{3,TL_WRITE_ALLOW_READ}}; /* Many writes */
 | |
| struct st_test test_13[] = {{0,TL_WRITE_CONCURRENT_INSERT},{1,TL_WRITE_CONCURRENT_INSERT},{2,TL_WRITE_CONCURRENT_INSERT},{3,TL_WRITE_CONCURRENT_INSERT}};
 | |
| struct st_test test_14[] = {{0,TL_WRITE_CONCURRENT_INSERT},{1,TL_READ}};
 | |
| struct st_test test_15[] = {{0,TL_WRITE_ALLOW_WRITE},{1,TL_READ}};
 | |
| struct st_test test_16[] = {{0,TL_WRITE_ALLOW_WRITE},{1,TL_WRITE_ALLOW_WRITE}};
 | |
| 
 | |
| struct st_test *tests[] = {test_0,test_1,test_2,test_3,test_4,test_5,test_6,
 | |
| 			   test_7,test_8,test_9,test_10,test_11,test_12,
 | |
| 			   test_13,test_14,test_15,test_16};
 | |
| int lock_counts[]= {sizeof(test_0)/sizeof(struct st_test),
 | |
| 		    sizeof(test_1)/sizeof(struct st_test),
 | |
| 		    sizeof(test_2)/sizeof(struct st_test),
 | |
| 		    sizeof(test_3)/sizeof(struct st_test),
 | |
| 		    sizeof(test_4)/sizeof(struct st_test),
 | |
| 		    sizeof(test_5)/sizeof(struct st_test),
 | |
| 		    sizeof(test_6)/sizeof(struct st_test),
 | |
| 		    sizeof(test_7)/sizeof(struct st_test),
 | |
| 		    sizeof(test_8)/sizeof(struct st_test),
 | |
| 		    sizeof(test_9)/sizeof(struct st_test),
 | |
| 		    sizeof(test_10)/sizeof(struct st_test),
 | |
| 		    sizeof(test_11)/sizeof(struct st_test),
 | |
| 		    sizeof(test_12)/sizeof(struct st_test),
 | |
| 		    sizeof(test_13)/sizeof(struct st_test),
 | |
| 		    sizeof(test_14)/sizeof(struct st_test),
 | |
| 		    sizeof(test_15)/sizeof(struct st_test),
 | |
| 		    sizeof(test_16)/sizeof(struct st_test)
 | |
| };
 | |
| 
 | |
| 
 | |
| static pthread_cond_t COND_thread_count;
 | |
| static pthread_mutex_t LOCK_thread_count;
 | |
| static uint thread_count;
 | |
| static ulong sum=0;
 | |
| 
 | |
| #define MAX_LOCK_COUNT 8
 | |
| 
 | |
| /* The following functions is for WRITE_CONCURRENT_INSERT */
 | |
| 
 | |
| static void test_get_status(void* param __attribute__((unused)),
 | |
|                             int concurrent_insert __attribute__((unused)))
 | |
| {
 | |
| }
 | |
| 
 | |
| static void test_copy_status(void* to __attribute__((unused)) ,
 | |
| 			     void *from __attribute__((unused)))
 | |
| {
 | |
| }
 | |
| 
 | |
| static my_bool test_check_status(void* param __attribute__((unused)))
 | |
| {
 | |
|   return 0;
 | |
| }
 | |
| 
 | |
| 
 | |
| static void *test_thread(void *arg)
 | |
| {
 | |
|   int i,j,param=*((int*) arg);
 | |
|   THR_LOCK_DATA data[MAX_LOCK_COUNT];
 | |
|   THR_LOCK_OWNER owner;
 | |
|   THR_LOCK_INFO lock_info;
 | |
|   THR_LOCK_DATA *multi_locks[MAX_LOCK_COUNT];
 | |
|   my_thread_init();
 | |
| 
 | |
|   printf("Thread %s (%d) started\n",my_thread_name(),param); fflush(stdout);
 | |
| 
 | |
| 
 | |
|   thr_lock_info_init(&lock_info);
 | |
|   thr_lock_owner_init(&owner, &lock_info);
 | |
|   for (i=0; i < lock_counts[param] ; i++)
 | |
|     thr_lock_data_init(locks+tests[param][i].lock_nr,data+i,NULL);
 | |
|   for (j=1 ; j < 10 ; j++)		/* try locking 10 times */
 | |
|   {
 | |
|     for (i=0; i < lock_counts[param] ; i++)
 | |
|     {					/* Init multi locks */
 | |
|       multi_locks[i]= &data[i];
 | |
|       data[i].type= tests[param][i].lock_type;
 | |
|     }
 | |
|     thr_multi_lock(multi_locks, lock_counts[param], &owner);
 | |
|     pthread_mutex_lock(&LOCK_thread_count);
 | |
|     {
 | |
|       int tmp=rand() & 7;			/* Do something from 0-2 sec */
 | |
|       if (tmp == 0)
 | |
| 	sleep(1);
 | |
|       else if (tmp == 1)
 | |
| 	sleep(2);
 | |
|       else
 | |
|       {
 | |
| 	ulong k;
 | |
| 	for (k=0 ; k < (ulong) (tmp-2)*100000L ; k++)
 | |
| 	  sum+=k;
 | |
|       }
 | |
|     }
 | |
|     pthread_mutex_unlock(&LOCK_thread_count);
 | |
|     thr_multi_unlock(multi_locks,lock_counts[param]);
 | |
|   }
 | |
| 
 | |
|   printf("Thread %s (%d) ended\n",my_thread_name(),param); fflush(stdout);
 | |
|   thr_print_locks();
 | |
|   pthread_mutex_lock(&LOCK_thread_count);
 | |
|   thread_count--;
 | |
|   VOID(pthread_cond_signal(&COND_thread_count)); /* Tell main we are ready */
 | |
|   pthread_mutex_unlock(&LOCK_thread_count);
 | |
|   free((gptr) arg);
 | |
|   return 0;
 | |
| }
 | |
| 
 | |
| 
 | |
| int main(int argc __attribute__((unused)),char **argv __attribute__((unused)))
 | |
| {
 | |
|   pthread_t tid;
 | |
|   pthread_attr_t thr_attr;
 | |
|   int i,*param,error;
 | |
|   MY_INIT(argv[0]);
 | |
|   if (argc > 1 && argv[1][0] == '-' && argv[1][1] == '#')
 | |
|     DBUG_PUSH(argv[1]+2);
 | |
| 
 | |
|   printf("Main thread: %s\n",my_thread_name());
 | |
| 
 | |
|   if ((error=pthread_cond_init(&COND_thread_count,NULL)))
 | |
|   {
 | |
|     fprintf(stderr,"Got error: %d from pthread_cond_init (errno: %d)",
 | |
| 	    error,errno);
 | |
|     exit(1);
 | |
|   }
 | |
|   if ((error=pthread_mutex_init(&LOCK_thread_count,MY_MUTEX_INIT_FAST)))
 | |
|   {
 | |
|     fprintf(stderr,"Got error: %d from pthread_cond_init (errno: %d)",
 | |
| 	    error,errno);
 | |
|     exit(1);
 | |
|   }
 | |
| 
 | |
|   for (i=0 ; i < (int) array_elements(locks) ; i++)
 | |
|   {
 | |
|     thr_lock_init(locks+i);
 | |
|     locks[i].check_status= test_check_status;
 | |
|     locks[i].update_status=test_get_status;
 | |
|     locks[i].copy_status=  test_copy_status;
 | |
|     locks[i].get_status=   test_get_status;
 | |
|   }
 | |
|   if ((error=pthread_attr_init(&thr_attr)))
 | |
|   {
 | |
|     fprintf(stderr,"Got error: %d from pthread_attr_init (errno: %d)",
 | |
| 	    error,errno);
 | |
|     exit(1);
 | |
|   }
 | |
|   if ((error=pthread_attr_setdetachstate(&thr_attr,PTHREAD_CREATE_DETACHED)))
 | |
|   {
 | |
|     fprintf(stderr,
 | |
| 	    "Got error: %d from pthread_attr_setdetachstate (errno: %d)",
 | |
| 	    error,errno);
 | |
|     exit(1);
 | |
|   }
 | |
| #ifndef pthread_attr_setstacksize		/* void return value */
 | |
|   if ((error=pthread_attr_setstacksize(&thr_attr,65536L)))
 | |
|   {
 | |
|     fprintf(stderr,"Got error: %d from pthread_attr_setstacksize (errno: %d)",
 | |
| 	    error,errno);
 | |
|     exit(1);
 | |
|   }
 | |
| #endif
 | |
| #ifdef HAVE_THR_SETCONCURRENCY
 | |
|   VOID(thr_setconcurrency(2));
 | |
| #endif
 | |
|   for (i=0 ; i < (int) array_elements(lock_counts) ; i++)
 | |
|   {
 | |
|     param=(int*) malloc(sizeof(int));
 | |
|     *param=i;
 | |
| 
 | |
|     if ((error=pthread_mutex_lock(&LOCK_thread_count)))
 | |
|     {
 | |
|       fprintf(stderr,"Got error: %d from pthread_mutex_lock (errno: %d)",
 | |
| 	      error,errno);
 | |
|       exit(1);
 | |
|     }
 | |
|     if ((error=pthread_create(&tid,&thr_attr,test_thread,(void*) param)))
 | |
|     {
 | |
|       fprintf(stderr,"Got error: %d from pthread_create (errno: %d)\n",
 | |
| 	      error,errno);
 | |
|       pthread_mutex_unlock(&LOCK_thread_count);
 | |
|       exit(1);
 | |
|     }
 | |
|     thread_count++;
 | |
|     pthread_mutex_unlock(&LOCK_thread_count);
 | |
|   }
 | |
| 
 | |
|   pthread_attr_destroy(&thr_attr);
 | |
|   if ((error=pthread_mutex_lock(&LOCK_thread_count)))
 | |
|     fprintf(stderr,"Got error: %d from pthread_mutex_lock\n",error);
 | |
|   while (thread_count)
 | |
|   {
 | |
|     if ((error=pthread_cond_wait(&COND_thread_count,&LOCK_thread_count)))
 | |
|       fprintf(stderr,"Got error: %d from pthread_cond_wait\n",error);
 | |
|   }
 | |
|   if ((error=pthread_mutex_unlock(&LOCK_thread_count)))
 | |
|     fprintf(stderr,"Got error: %d from pthread_mutex_unlock\n",error);
 | |
|   for (i=0 ; i < (int) array_elements(locks) ; i++)
 | |
|     thr_lock_delete(locks+i);
 | |
| #ifdef EXTRA_DEBUG
 | |
|   if (found_errors)
 | |
|     printf("Got %d warnings\n",found_errors);
 | |
|   else
 | |
| #endif
 | |
|     printf("Test succeeded\n");
 | |
|   return 0;
 | |
| }
 | |
| 
 | |
| #else /* THREAD */
 | |
| 
 | |
| int main(int argc __attribute__((unused)),char **argv __attribute__((unused)))
 | |
| {
 | |
|   printf("thr_lock disabled because we are not using threads\n");
 | |
|   exit(1);
 | |
| }
 | |
| 
 | |
| #endif /* THREAD */
 | |
| #endif /* MAIN */
 |