PERFORCE change 120767 for review

[Fredrik Lindberg]

http://perforce.freebsd.org/chv.cgi?CH=120767

Change 120767 by fli at fli_genesis on 2007/06/02 11:56:33

	- Add debugging macros.
	- No need to hold read lock during event handle execution.
	- Style fixes.

Affected files ...

.. //depot/projects/soc2007/fli-mdns_sd/mdnsd/event.c#2 edit
.. //depot/projects/soc2007/fli-mdns_sd/mdnsd/event.h#2 edit

Differences ...

==== //depot/projects/soc2007/fli-mdns_sd/mdnsd/event.c#2 (text+ko) ====

@@ -24,10 +24,11 @@
  *
  */
 
-#include <stdlib.h>
-#include <stdio.h>
 #include <sys/types.h>
 #include <sys/event.h>
+
+#include <stdio.h>
+#include <stdlib.h>
 #include <signal.h>
 #include <string.h>
 #include <strings.h>
@@ -36,6 +37,7 @@
 #include "event.h"
 #include "wqueue.h"
 #include "log.h"
+#include "debug.h"
 
 static int remove_event(struct eventlist *, struct event *, ev_arg *);
 static int event_engine(wq_arg);
@@ -76,6 +78,7 @@
 #ifdef HAVE_PTHREAD
 	pthread_mutex_init(&evl->evl_mtx, NULL);
 #endif
+	MDNS_INIT_SET(evl, evl_magic);
 	return (evl);
 }
 
@@ -91,6 +94,7 @@
 	struct event *ev;
 	int empty;
 
+	MDNS_INIT_ASSERT(evl, evl_magic);
 	EVL_LOCK(evl);
 	while (!TAILQ_EMPTY(&evl->evl_events)) {
 		ev = TAILQ_FIRST(&evl->evl_events);
@@ -107,6 +111,7 @@
 #ifdef HAVE_PTHREAD
 		pthread_mutex_destroy(&evl->evl_mtx);
 #endif
+		MDNS_INIT_UNSET(evl, evl_magic);
 		free(evl);
 	}
 	else {
@@ -130,9 +135,8 @@
 	int ret;
 
 	ev = (struct event *)arg.ptr;
+	MDNS_INIT_ASSERT(ev, ev_magic);
 
-	/* Grab a read-lock during the time we execute the handler */
-	EV_RLOCK(ev);
 	switch (ev->ev_type) {
 	case EVENT_TYPE_IO:
 		ret = ev->ev_cb.ev_handler.io(&ev->ev_data.io, ev->ev_handler_arg);
@@ -145,15 +149,15 @@
 		break;
 	}
 
-	/* "Upgrade" to write-lock */
-	EV_UNLOCK(ev);
 	EV_WLOCK(ev);
 	ev->ev_refcnt--;
 	if (ev->ev_flags & EVENT_FLAG_DYING) {
 		evl = ev->ev_evl;
 		remove_event(evl, ev, NULL);
 	}
-	EV_UNLOCK(ev);
+	else {
+		EV_UNLOCK(ev);
+	}
 	return (0);
 }
 
@@ -174,6 +178,7 @@
 	wq_arg wa;
 	struct kevent kev;
 
+	MDNS_INIT_ASSERT(evl, evl_magic);
 	EVL_LOCK(evl);
 	kq = evl->evl_kq;
 	EVL_UNLOCK(evl);
@@ -219,14 +224,17 @@
 		}
 
 		/* Exclusive event already in progress */
-		if (ev->ev_flags & EVENT_FLAG_EX && ev->ev_refcnt > 0)  {
+		if ((ev->ev_flags & EVENT_FLAG_EX) && ev->ev_refcnt > 0)  {
+			dprintf(DEBUG_EVENT,
+				"Exclusive event already in progress ev=%x", ev); 
 			EV_UNLOCK(ev);
 			continue;
 		}
 
 		ev->ev_refcnt++;
 		EV_UNLOCK(ev);
-		dprintf(DEBUG_EVENT, "Event fired, dispatched to queue=%x, ev=%x", wq, ev);
+		dprintf(DEBUG_EVENT, "Event fired, dispatched to queue=%x, ev=%x",
+		    wq, ev);
 		wa.ptr = ev;
 #ifdef HAVE_PTHREAD
 		error = wq_enqueue(wq, event_engine, &wa);
@@ -250,6 +258,7 @@
 {
 	pid_t self;
 
+	MDNS_INIT_ASSERT(evl, evl_magic);
 	EVL_LOCK(evl);
 	dprintf(DEBUG_EVENT, "Event exit called");
 	evl->evl_flags |= EVL_FLAG_DYING;
@@ -282,6 +291,7 @@
 	ev_arg ev_arg_init;
 	struct kevent kev;
 
+	MDNS_INIT_ASSERT(evl, evl_magic);
 	ev = malloc(sizeof(struct event));
 	if (ev == NULL)
 		return (-1);
@@ -364,9 +374,10 @@
 		TAILQ_INSERT_TAIL(&evl->evl_events, ev, ev_evlist);
 		EVL_UNLOCK(evl);
 	}
+	MDNS_INIT_SET(ev, ev_magic);
 
-	dprintf(DEBUG_EVENT, "Event added type=%d, ev=%x, handler=%x",
-		type, ev, handler);
+	dprintf(DEBUG_EVENT, "Event added type=%d, id=%d, ev=%x, handler=%x",
+		type, ev->ev_id, ev, handler);
 	return (ev->ev_id);
 }
 
@@ -384,8 +395,7 @@
 {
 	struct event *ev = NULL;
 
-	dprintf(DEBUG_EVENT, "Removing event ev=%x", ev);
-
+	MDNS_INIT_ASSERT(evl, evl_magic);
 	EVL_LOCK(evl);
 	TAILQ_FOREACH(ev, &evl->evl_events, ev_evlist) {
 		if (ev->ev_id == id)
@@ -397,12 +407,13 @@
 		return (-1);
 	}
 	EV_WLOCK(ev);
+	dprintf(DEBUG_EVENT, "Removing event ev=%x", ev);
 
 	if (remove_event(evl, ev, arg) == 1) {
 		EV_UNLOCK(ev);
 	}
 
-	return (ev->ev_id);
+	return (0);
 }
 
 /*
@@ -420,6 +431,9 @@
 	ev_arg ev_arg_init;
 	struct kevent kev;
 
+	MDNS_INIT_ASSERT(evl, evl_magic);
+	MDNS_INIT_ASSERT(ev, ev_magic);
+
 	if (ev->ev_refcnt > 0) {
 		dprintf(DEBUG_EVENT, "Event busy ev=%x, refcnt=%d", ev, ev->ev_refcnt);
 		ev->ev_flags |= EVENT_FLAG_DYING;
@@ -468,6 +482,7 @@
 
 	kev.flags |= EV_DELETE | EV_CLEAR;
 	ret = kevent(evl->evl_kq, &kev, 1, NULL, 0, NULL);
+	MDNS_INIT_UNSET(ev, ev_magic);
 	free(ev);
 
 	dprintf(DEBUG_EVENT, "Event removed ev=%x", ev);

==== //depot/projects/soc2007/fli-mdns_sd/mdnsd/event.h#2 (text+ko) ====

@@ -31,6 +31,7 @@
 #include <sys/queue.h>
 
 #include "wqueue.h"
+#include "debug.h"
 
 /*
  * Holds event id and backpointer to event list, included
@@ -97,6 +98,7 @@
  */
 struct event;
 struct eventlist {
+	MAGIC(evl_magic);
 	TAILQ_HEAD(, event) evl_events; /* list of events */
 #ifdef HAVE_PTHREAD
 	pthread_mutex_t evl_mtx;
@@ -111,6 +113,7 @@
  * Internal event structure, represents an event
  */
 struct event {
+	MAGIC(ev_magic);
 	TAILQ_ENTRY(event) ev_evlist; /* global event list */
 	struct eventlist *ev_evl;	/* back-pointer to list */
 #ifdef HAVE_PTHREAD