diff options
| -rw-r--r-- | sys/netgraph/ng_base.c | 99 |
1 files changed, 85 insertions, 14 deletions
diff --git a/sys/netgraph/ng_base.c b/sys/netgraph/ng_base.c index b029ab8c..983247b 100644 --- a/sys/netgraph/ng_base.c +++ b/sys/netgraph/ng_base.c @@ -192,7 +192,7 @@ static ng_ID_t ng_decodeidname(const char *name); static int ngb_mod_event(module_t mod, int event, void *data); static void ng_worklist_remove(node_p node); static void ngintr(void); -static int ng_apply_item(node_p node, item_p item, int rw); +static void ng_apply_item(node_p node, item_p item, int rw); static void ng_flush_input_queue(struct ng_queue * ngq); static void ng_setisr(node_p node); static node_p ng_ID2noderef(ng_ID_t ID); @@ -2101,6 +2101,80 @@ restart: return (NULL); } +#if 0 +static __inline item_p +ng_upgrade_write(struct ng_queue *ngq, item_p item) +{ + KASSERT(ngq != &ng_deadnode.nd_input_queue, + ("%s: working on deadnode", __func__)); + + NGI_SET_WRITER(item); + + mtx_lock_spin(&(ngq->q_mtx)); + + /* + * There will never be no readers as we are there ourselves. + * Set the WRITER_ACTIVE flags ASAP to block out fast track readers. + * The caller we are running from will call ng_leave_read() + * soon, so we must account for that. We must leave again with the + * READER lock. If we find other readers, then + * queue the request for later. However "later" may be rignt now + * if there are no readers. We don't really care if there are queued + * items as we will bypass them anyhow. + */ + atomic_add_long(&ngq->q_flags, WRITER_ACTIVE - READER_INCREMENT); + if (ngq->q_flags & (NGQ_WMASK & ~OP_PENDING) == WRITER_ACTIVE) { + mtx_unlock_spin(&(ngq->q_mtx)); + + /* It's just us, act on the item. */ + /* will NOT drop writer lock when done */ + ng_apply_item(node, item, 0); + + /* + * Having acted on the item, atomically + * down grade back to READER and finish up + */ + atomic_add_long(&ngq->q_flags, + READER_INCREMENT - WRITER_ACTIVE); + + /* Our caller will call ng_leave_read() */ + return; + } + /* + * It's not just us active, so queue us AT THE HEAD. + * "Why?" I hear you ask. + * Put us at the head of the queue as we've already been + * through it once. If there is nothing else waiting, + * set the correct flags. + */ + if ((item->el_next = ngq->queue) == NULL) { + /* + * Set up the "last" pointer. + * We are the only (and thus last) item + */ + ngq->last = &(item->el_next); + + /* We've gone from, 0 to 1 item in the queue */ + atomic_add_long(&ngq->q_flags, OP_PENDING); + + CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__, + ngq->q_node->nd_ID, ngq->q_node); + }; + ngq->queue = item; + CTR5(KTR_NET, "%20s: node [%x] (%p) requeued item %p as WRITER", + __func__, ngq->q_node->nd_ID, ngq->q_node, item ); + + /* Reverse what we did above. That downgrades us back to reader */ + atomic_add_long(&ngq->q_flags, READER_INCREMENT - WRITER_ACTIVE); + if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) + ng_setisr(ngq->q_node); + mtx_unlock_spin(&(ngq->q_mtx)); + + return; +} + +#endif + static __inline void ng_leave_read(struct ng_queue *ngq) { @@ -2298,7 +2372,8 @@ ng_snd_item(item_p item, int flags) NGI_GET_NODE(item, node); /* zaps stored node */ - error = ng_apply_item(node, item, rw); /* drops r/w lock when done */ + /* Don't report any errors. act as if it had been queued */ + ng_apply_item(node, item, rw); /* drops r/w lock when done */ /* * If the node goes away when we remove the reference, @@ -2322,11 +2397,10 @@ ng_snd_item(item_p item, int flags) * It should contain all the information needed * to run it on the appropriate node/hook. */ -static int +static void ng_apply_item(node_p node, item_p item, int rw) { hook_p hook; - int error = 0; ng_rcvdata_t *rcvdata; ng_rcvmsg_t *rcvmsg; ng_apply_t *apply = NULL; @@ -2356,7 +2430,6 @@ ng_apply_item(node_p node, item_p item, int rw) if ((hook == NULL) || NG_HOOK_NOT_VALID(hook) || NG_NODE_NOT_VALID(node) ) { - error = EIO; NG_FREE_ITEM(item); break; } @@ -2370,7 +2443,7 @@ ng_apply_item(node_p node, item_p item, int rw) NG_FREE_ITEM(item); break; } - error = (*rcvdata)(hook, item); + (*rcvdata)(hook, item); break; case NGQF_MESG: if (hook) { @@ -2390,7 +2463,6 @@ ng_apply_item(node_p node, item_p item, int rw) */ if (NG_NODE_NOT_VALID(node)) { TRAP_ERROR(); - error = EINVAL; NG_FREE_ITEM(item); } else { /* @@ -2412,7 +2484,7 @@ ng_apply_item(node_p node, item_p item, int rw) */ if ((msg->header.typecookie == NGM_GENERIC_COOKIE) && ((msg->header.flags & NGF_RESP) == 0)) { - error = ng_generic_msg(node, item, hook); + ng_generic_msg(node, item, hook); break; } /* @@ -2422,11 +2494,10 @@ ng_apply_item(node_p node, item_p item, int rw) if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) && (!(rcvmsg = node->nd_type->rcvmsg))) { TRAP_ERROR(); - error = 0; NG_FREE_ITEM(item); break; } - error = (*rcvmsg)(node, item, hook); + (*rcvmsg)(node, item, hook); } break; case NGQF_FN: @@ -2440,7 +2511,6 @@ ng_apply_item(node_p node, item_p item, int rw) if ((NG_NODE_NOT_VALID(node)) && (NGI_FN(item) != &ng_rmnode)) { TRAP_ERROR(); - error = EINVAL; NG_FREE_ITEM(item); break; } @@ -2460,15 +2530,16 @@ ng_apply_item(node_p node, item_p item, int rw) if (rw == NGQRW_R) { ng_leave_read(&node->nd_input_queue); - } else { + } else if (rw == NGQRW_W) { ng_leave_write(&node->nd_input_queue); - } + } /* else do nothing */ + /* Apply callback. */ if (apply != NULL) (*apply)(context, error); - return (error); + return; } /*********************************************************************** |
