function delete_flow() is called inside mapid_process_pkt(). Thus, race...

function delete_flow() is called inside mapid_process_pkt(). Thus, race condition with process packet thread is avoided

git-svn-id: file:///home/svn/mapi/trunk@1319 8d5bb341-7cf1-0310-8cf6-ba355fef3186

src/drivers/mapidagdrv.c

@@ -268,7 +268,7 @@ process_pkts(void *buf,unsigned len, dag_instance_t *i)
       i->hwinfo.pkts++;
     }
 
-  mapid_delete_flows(&i->mapidlib);
+  //mapid_delete_flows(&i->mapidlib);
 
   return len - c;
 
@@ -313,7 +313,7 @@ process_pkts_offline(void *buf,unsigned len, dag_instance_t *i)
       i->hwinfo.pkts++;
     }
 
-  mapid_delete_flows(&i->mapidlib);
+  //mapid_delete_flows(&i->mapidlib);
 
   return len - c;
 

src/drivers/mapidlib.c

@@ -116,9 +116,6 @@ mapid_init(mapidlib_instance_t *i)
   struct group *mapi_group;
   struct shmid_ds shm_data;
 
-  pthread_mutex_init(&i->lock,NULL);
-  flist_init(&i->close);
-
 #ifdef WITH_PRIORITIES
   int j = 0;
   i->flowlist=malloc(sizeof(flist_t*) * PRIORITIES);
@@ -135,7 +132,6 @@ mapid_init(mapidlib_instance_t *i)
 #endif
 
   if(!libs_loaded) {
-    //mapid_conf = printf_string(CONF_FILE,getenv("HOME"));
     mapid_conf = printf_string( CONFDIR"/"CONF_FILE );
 
     //Load function libraries
@@ -541,19 +537,21 @@ static void delete_flow(mapidlib_instance_t *i,struct mapidlibflow *flow) {
 
   DEBUG_CMD(Debug_Message("Deleting flow %d", flow->fd));
   
-  //global optimization
-  temp = (void*)flist_get(flow->hwinfo->gflist->fflist,flow->fd);
+  ((mapid_flow_info_t*)flist_get(flow->hwinfo->gflist->fflist,flow->fd))->status = FLOW_CLOSED;	// Update global function list
+  time(&flow->end);	// moved from mapid_close_flow
+  temp = (void*)flist_get(flow->hwinfo->gflist->fflist,flow->fd);	// global optimization
+
   if(!temp){
 	  DEBUG_CMD(Debug_Message("ERROR: Attempt to delete a flow that doesnt exist"));
 	  return;
   }
-  functions= ((mapid_flow_info_t*)temp)->flist;
+  functions = ((mapid_flow_info_t*)temp)->flist;
+
   if(functions!=NULL)
     for(funct_node=flist_head(functions);funct_node!=NULL;funct_node=flist_next(funct_node)) {
       funct=(mapidflib_function_t*)flist_data(funct_node);
       if(funct->ref==0 && funct->instance->refcount>0 )
-	//Check to see if other functions references this function
-	fix_funct_ref(flow->hwinfo->gflist,funct);
+	fix_funct_ref(flow->hwinfo->gflist,funct);	// Check to see if other functions references this function
     }
 
 #ifdef WITH_MODIFY_PKTS
@@ -561,10 +559,6 @@ static void delete_flow(mapidlib_instance_t *i,struct mapidlibflow *flow) {
     free(flow->mod_pkt);
 #endif
 
-// commented: lock moved to free_functionlist()
-//  lock=&flow->hwinfo->gflist->lock;  
-//  pthread_spin_lock(lock);
-
 #ifdef WITH_PRIORITIES
   f=flist_remove(i->flowlist[flow->priority],flow->fd);
 #else
@@ -585,12 +579,9 @@ static void delete_flow(mapidlib_instance_t *i,struct mapidlibflow *flow) {
   free_functionlist(f);
   free_sharedmem(f);
   free(f);
-
-//  pthread_spin_unlock(lock);
 }
 
-
-void mapid_delete_flows(mapidlib_instance_t *i) {
+/*void mapid_delete_flows(mapidlib_instance_t *i) {	// TODO delete this function ...
   flist_node_t *n;
   int fd;
 
@@ -605,7 +596,7 @@ void mapid_delete_flows(mapidlib_instance_t *i) {
   }
   
   pthread_mutex_unlock(&i->lock);
-}
+}*/
 
 
 //Frees resources allocated by mapidlib, should be called by the drivers when devices are deleted
@@ -975,8 +966,6 @@ int
 mapid_close_flow(mapidlib_instance_t *i,int fd)
 {
   struct mapidlibflow *f;
-  mapidflib_function_t *fn;
-  flist_node_t *fnode;
 
 #ifdef WITH_PRIORITIES
   f=flist_priorities_get(i->flowlist,fd);
@@ -987,30 +976,8 @@ mapid_close_flow(mapidlib_instance_t *i,int fd)
   if(f==NULL)
     return -1;
 
-  f->status=FLOW_CLOSED;
-  //Update global function list
-  ((mapid_flow_info_t*)flist_get(f->hwinfo->gflist->fflist,f->fd))->status=FLOW_CLOSED;  
-  time(&f->end);
-
-  pthread_mutex_lock(&i->lock);
-  
-  DEBUG_CMD(Debug_Message("Added flow to delete list, fd=%d", fd));
-  flist_append(&i->close,fd, (void *)0x1); /* 0x1 ... so flist_get works as exist operator */
-
-  for(fnode = flist_head(f->functionlist); fnode != NULL; fnode = flist_next(fnode)){
-	  
-	  fn = flist_data(fnode);
+  f->status = FLOW_CLOSED; // flow is deleted in mapid_process_pkt, in order to avoid a race condition with process packet thread
 
-	  if(fn->instance->def->cleanup != NULL && fn->instance->status == MAPIFUNC_INIT){
-		  fn->instance->def->cleanup(fn->instance);
-		  fn->instance->status = MAPIFUNC_UNINIT;	// in order to avoid the unnecessary call of cleanup function in free_functionlist()
-	  }
-  }
-
-  pthread_mutex_unlock(&i->lock);
-
-//it is not possible to delete flows here as it can cause race condition with process packet thread
-//  delete_flow(i, f);
   return 0;
 }
 
@@ -1371,7 +1338,7 @@ mapid_apply_function(mapidlib_instance_t *i,
   return fid;
 }
 
-int mapid_finished(mapidlib_instance_t *i)
+int mapid_finished(mapidlib_instance_t *i)	// XXX is this function essential ???
 {
   flist_node_t *n;
   struct mapidlibflow *flow;
@@ -1404,15 +1371,6 @@ int mapid_finished(mapidlib_instance_t *i)
     }
 #endif
 
-/*
-  n = flist_head(i->flowlist);
-  while (n)
-    {
-      flow=flist_data(n);
-      flow->status=FLOW_FINISHED;
-      n = flist_next(n);
-    }
-*/
   return 0;
 }
 
@@ -1569,6 +1527,9 @@ void mapid_process_pkt(mapidlib_instance_t *i,
 	  n2 = flist_next(n2);	      	
 	}
       }
+      else if(flow->status == FLOW_CLOSED){	// flow has closed, so we can delete it and deallocate all of its resources
+	      delete_flow(i, flow);
+      }
     }
 #ifdef WITH_PRIORITIES
   }

src/drivers/mapidlib.h

@@ -54,8 +54,6 @@ typedef struct mapidlib_instance {
   key_t shm_spinlock_key;
   int shm_spinlock_id;
   char shm_spinlock_fname[MAPI_STR_LENGTH];
-  pthread_mutex_t lock;
-  flist_t close;
 
 }mapidlib_instance_t;
 
@@ -119,7 +117,7 @@ void mapid_process_pkt(mapidlib_instance_t *i,
 		       unsigned char* link_pkt,
 		       mapid_pkthdr_t* pkt_head);
 int mapid_get_errno(mapidlib_instance_t *i,int fid);
-void mapid_delete_flows(mapidlib_instance_t *i);
+//void mapid_delete_flows(mapidlib_instance_t *i);
 int mapid_get_devid(mapidlib_instance_t *i,int fd);
 int mapid_load_library(char *lib);
 int mapid_get_flow_info(mapidlib_instance_t *i,int fd,mapi_flow_info_t *info);

src/drivers/mapinicdrv.c

@@ -201,7 +201,7 @@ process_pkts(void *buf,unsigned len, nic_instance_t *i,MAPI_UNUSED int devid, in
       rlen = rec->caplen+sizeof(struct pcap_pkthdr);
     }
 
-  mapid_delete_flows(&i->mapidlib);
+  //mapid_delete_flows(&i->mapidlib);
 
   return len - c;