usrloc: use recursive locks for location hash table

- allow recursive access to the same slot
- reported by Olle E. Johansson, GH #577

modules/usrloc/hslot.c

@@ -29,113 +29,23 @@
 
 #include "hslot.h"
 
-/*! number of locks */
-int ul_locks_no=4;
-/*! global list of locks */
-gen_lock_set_t* ul_locks=0;
-
-
-/*!
- * \brief Initialize locks for the hash table
- * \return 0 on success, -1 on failure
- */
-int ul_init_locks(void)
-{
-	int i;
-	i = ul_locks_no;
-	do {
-		if ((( ul_locks=lock_set_alloc(i))!=0)&&
-				(lock_set_init(ul_locks)!=0))
-		{
-			ul_locks_no = i;
-			LM_INFO("locks array size %d\n", ul_locks_no);
-			return 0;
-
-		}
-		if (ul_locks){
-			lock_set_dealloc(ul_locks);
-			ul_locks=0;
-		}
-		i--;
-		if(i==0)
-		{
-			LM_ERR("failed to allocate locks\n");
-			return -1;
-		}
-	} while (1);
-}
-
-
-/*!
- * \brief Unlock all locks on the list
- */
-void ul_unlock_locks(void)
-{
-	unsigned int i;
-
-	if (ul_locks==0)
-		return;
-
-	for (i=0;i<ul_locks_no;i++) {
-#ifdef GEN_LOCK_T_PREFERED
-		lock_release(&ul_locks->locks[i]);
-#else
-		ul_release_idx(i);
-#endif
-	};
-}
-
-
-/*!
- * \brief Destroy all locks on the list
- */
-void ul_destroy_locks(void)
-{
-	if (ul_locks !=0){
-		lock_set_destroy(ul_locks);
-		lock_set_dealloc(ul_locks);
-	};
-}
-
-#ifndef GEN_LOCK_T_PREFERED
-/*!
- * \brief Lock a lock with a certain index
- * \param idx lock index
- */
-void ul_lock_idx(int idx)
-{
-	lock_set_get(ul_locks, idx);
-}
-
-
-/*!
- * \brief Release a lock with a certain index
- * \param idx lock index
- */
-void ul_release_idx(int idx)
-{
-	lock_set_release(ul_locks, idx);
-}
-#endif
-
 /*!
  * \brief Initialize cache slot structure
  * \param _d domain for the hash slot
  * \param _s hash slot
  * \param n used to get the slot number (modulo number or locks)
  */
-void init_slot(struct udomain* _d, hslot_t* _s, int n)
+int init_slot(struct udomain* _d, hslot_t* _s, int n)
 {
 	_s->n = 0;
 	_s->first = 0;
 	_s->last = 0;
 	_s->d = _d;
-
-#ifdef GEN_LOCK_T_PREFERED
-	_s->lock = &ul_locks->locks[n%ul_locks_no];
-#else
-	_s->lockidx = n%ul_locks_no;
-#endif
+	if(rec_lock_init(&_s->rlock)==NULL) {
+		LM_ERR("failed to initialize the slock (%d)\n", n);
+		return -1;
+	}
+	return 0;
 }
 
 
@@ -146,14 +56,15 @@ void init_slot(struct udomain* _d, hslot_t* _s, int n)
 void deinit_slot(hslot_t* _s)
 {
 	struct urecord* ptr;
-	
-	     /* Remove all elements */
+
+	/* Remove all elements */
 	while(_s->first) {
 		ptr = _s->first;
 		_s->first = _s->first->next;
 		free_urecord(ptr);
 	}
-	
+	rec_lock_destroy(&_s->rlock);
+
 	_s->n = 0;
 	_s->last = 0;
     _s->d = 0;

modules/usrloc/hslot.h

@@ -13,8 +13,8 @@
  * 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 
+ * 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  */
 
@@ -43,17 +43,13 @@ typedef struct hslot {
 	struct urecord* first;  /*!< First element in the list */
 	struct urecord* last;   /*!< Last element in the list */
 	struct udomain* d;      /*!< Domain we belong to */
-#ifdef GEN_LOCK_T_PREFERED
-	gen_lock_t *lock;       /*!< Lock for hash entry - fastlock */
-#else
-	int lockidx;            /*!< Lock index for hash entry - the rest*/
-#endif
+	rec_lock_t rlock;       /*!< Recursive lock for hash entry */
 } hslot_t;
 
 /*! \brief
  * Initialize slot structure
  */
-void init_slot(struct udomain* _d, hslot_t* _s, int n);
+int init_slot(struct udomain* _d, hslot_t* _s, int n);
 
 
 /*! \brief
@@ -73,23 +69,4 @@ void slot_add(hslot_t* _s, struct urecord* _r);
  */
 void slot_rem(hslot_t* _s, struct urecord* _r);
 
-
-/*!
- * \brief Initialize locks for the hash table
- * \return 0 on success, -1 on failure
- */
-int ul_init_locks(void);
-
-
-/*!
- * \brief Destroy all locks on the list
- */
-void ul_unlock_locks(void);
-void ul_destroy_locks(void);
-
-#ifndef GEN_LOCK_T_PREFERED
-void ul_lock_idx(int idx);
-void ul_release_idx(int idx);
-#endif
-
 #endif /* HSLOT_H */

modules/usrloc/udomain.c

@@ -35,6 +35,7 @@
 #include "../../socket_info.h"
 #include "../../ut.h"
 #include "../../hashes.h"
+#include "../../sr_module.h"
 #include "ul_mod.h"            /* usrloc module parameters */
 #include "usrloc.h"
 #include "utime.h"
@@ -89,7 +90,7 @@ int new_udomain(str* _n, int _s, udomain_t** _d)
 		goto error0;
 	}
 	memset(*_d, 0, sizeof(udomain_t));
-	
+
 	(*_d)->table = (hslot_t*)shm_malloc(sizeof(hslot_t) * _s);
 	if (!(*_d)->table) {
 		LM_ERR("no memory left 2\n");
@@ -97,9 +98,12 @@ int new_udomain(str* _n, int _s, udomain_t** _d)
 	}
 
 	(*_d)->name = _n;
-	
+
 	for(i = 0; i < _s; i++) {
-		init_slot(*_d, &((*_d)->table[i]), i);
+		if(init_slot(*_d, &((*_d)->table[i]), i)<0) {
+			LM_ERR("failed to init hash table slot %d\n", i);
+			goto error2;
+		}
 	}
 
 	(*_d)->size = _s;
@@ -145,9 +149,7 @@ void free_udomain(udomain_t* _d)
 	
 	if (_d->table) {
 		for(i = 0; i < _d->size; i++) {
-			lock_ulslot(_d, i);
 			deinit_slot(_d->table + i);
-			unlock_ulslot(_d, i);
 		}
 		shm_free(_d->table);
 	}
@@ -1005,7 +1007,7 @@ void mem_timer_udomain(udomain_t* _d, int istart, int istep)
 
 	for(i=istart; i<_d->size; i+=istep)
 	{
-		lock_ulslot(_d, i);
+		if(likely(destroy_modules_phase()==0)) lock_ulslot(_d, i);
 
 		ptr = _d->table[i].first;
 
@@ -1020,7 +1022,7 @@ void mem_timer_udomain(udomain_t* _d, int istart, int istep)
 				ptr = ptr->next;
 			}
 		}
-		unlock_ulslot(_d, i);
+		if(likely(destroy_modules_phase()==0)) unlock_ulslot(_d, i);
 	}
 }
 
@@ -1037,11 +1039,7 @@ void lock_udomain(udomain_t* _d, str* _aor)
 	{
 		sl = ul_get_aorhash(_aor) & (_d->size - 1);
 
-#ifdef GEN_LOCK_T_PREFERED
-		lock_get(_d->table[sl].lock);
-#else
-		ul_lock_idx(_d->table[sl].lockidx);
-#endif
+		rec_lock_get(&_d->table[sl].rlock);
 	}
 }
 
@@ -1057,11 +1055,7 @@ void unlock_udomain(udomain_t* _d, str* _aor)
 	if (db_mode!=DB_ONLY)
 	{
 		sl = ul_get_aorhash(_aor) & (_d->size - 1);
-#ifdef GEN_LOCK_T_PREFERED
-		lock_release(_d->table[sl].lock);
-#else
-		ul_release_idx(_d->table[sl].lockidx);
-#endif
+		rec_lock_release(&_d->table[sl].rlock);
 	}
 }
 
@@ -1073,11 +1067,7 @@ void unlock_udomain(udomain_t* _d, str* _aor)
 void lock_ulslot(udomain_t* _d, int i)
 {
 	if (db_mode!=DB_ONLY)
-#ifdef GEN_LOCK_T_PREFERED
-		lock_get(_d->table[i].lock);
-#else
-		ul_lock_idx(_d->table[i].lockidx);
-#endif
+		rec_lock_get(&_d->table[i].rlock);
 }
 
 
@@ -1089,11 +1079,7 @@ void lock_ulslot(udomain_t* _d, int i)
 void unlock_ulslot(udomain_t* _d, int i)
 {
 	if (db_mode!=DB_ONLY)
-#ifdef GEN_LOCK_T_PREFERED
-		lock_release(_d->table[i].lock);
-#else
-		ul_release_idx(_d->table[i].lockidx);
-#endif
+		rec_lock_release(&_d->table[i].rlock);
 }
 
 

modules/usrloc/ul_mod.c

@@ -105,7 +105,6 @@ static int ul_preload_index = 0;
 static int ul_preload_param(modparam_t type, void* val);
 
 extern int bind_usrloc(usrloc_api_t* api);
-extern int ul_locks_no;
 int ul_db_update_as_insert = 0;
 int ul_timer_procs = 0;
 int ul_db_check_update = 0;
@@ -314,7 +313,6 @@ static int mod_init(void)
 		ul_hash_size = 512;
 	else
 		ul_hash_size = 1<<ul_hash_size;
-	ul_locks_no = ul_hash_size;
 
 	/* check matching mode */
 	switch (matching_mode) {
@@ -327,12 +325,6 @@ static int mod_init(void)
 			LM_ERR("invalid matching mode %d\n", matching_mode);
 	}
 
-	if(ul_init_locks()!=0)
-	{
-		LM_ERR("locks array initialization failed\n");
-		return -1;
-	}
-
 	/* Register cache timer */
 	if(ul_timer_procs<=0)
 	{
@@ -493,7 +485,6 @@ static void destroy(void)
 {
 	/* we need to sync DB in order to flush the cache */
 	if (ul_dbh) {
-		ul_unlock_locks();
 		if (synchronize_all_udomains(0, 1) != 0) {
 			LM_ERR("flushing cache failed\n");
 		}
@@ -501,7 +492,6 @@ static void destroy(void)
 	}
 
 	free_all_udomains();
-	ul_destroy_locks();
 
 	/* free callbacks list */
 	destroy_ulcb_list();