- Change process_exec function handlers prototype to include struct

image_params arg.
- Change struct image_params to include struct sysentvec pointer and
  initialize it.
- Change all consumers of process_exit/process_exec eventhandlers to
  new prototypes (includes splitting up into distinct exec/exit functions).
- Add eventhandler to userret.

Sponsored by:		Google SoC 2006
Submitted by:		rdivacky
Parts suggested by:	jhb (on hackers@)

sys/kern/kern_exec.c

@@ -889,9 +889,10 @@ exec_new_vmspace(imgp, sv)
 	vm_map_t map;
 
 	imgp->vmspace_destroyed = 1;
+	imgp->sysent = sv;
 
 	/* Called with Giant held, do not depend on it! */
-	EVENTHANDLER_INVOKE(process_exec, p);
+	EVENTHANDLER_INVOKE(process_exec, p, imgp);
 
 	/*
 	 * Here is as good a place as any to do any resource limit cleanups.

sys/kern/kern_fork.c

@@ -827,6 +827,8 @@ fork_exit(callout, arg, frame)
 		kthread_exit(0);
 	}
 	mtx_assert(&Giant, MA_NOTOWNED);
+
+	EVENTHANDLER_INVOKE(schedtail, p);
 }
 
 /*

sys/kern/kern_time.c

@@ -88,7 +88,8 @@ static void	itimer_enter(struct itimer *);
 static void	itimer_leave(struct itimer *);
 static struct itimer *itimer_find(struct proc *, int, int);
 static void	itimers_alloc(struct proc *);
-static void	itimers_event_hook(void *arg, struct proc *p);
+static void	itimers_event_hook_exec(void *arg, struct proc *p, struct image_params *imgp);
+static void	itimers_event_hook_exit(void *arg, struct proc *p);
 static int	realtimer_create(struct itimer *);
 static int	realtimer_gettime(struct itimer *, struct itimerspec *);
 static int	realtimer_settime(struct itimer *, int,
@@ -892,9 +893,9 @@ itimer_start(void)
 	p31b_setcfg(CTL_P1003_1B_TIMERS, 200112L);
 	p31b_setcfg(CTL_P1003_1B_DELAYTIMER_MAX, INT_MAX);
 	p31b_setcfg(CTL_P1003_1B_TIMER_MAX, TIMER_MAX);
-	EVENTHANDLER_REGISTER(process_exit, itimers_event_hook,
+	EVENTHANDLER_REGISTER(process_exit, itimers_event_hook_exit,
 		(void *)ITIMER_EV_EXIT, EVENTHANDLER_PRI_ANY);
-	EVENTHANDLER_REGISTER(process_exec, itimers_event_hook,
+	EVENTHANDLER_REGISTER(process_exec, itimers_event_hook_exec,
 		(void *)ITIMER_EV_EXEC, EVENTHANDLER_PRI_ANY);
 }
 
@@ -1510,9 +1511,15 @@ itimers_alloc(struct proc *p)
 	}
 }
 
+static void
+itimers_event_hook_exec(void *arg, struct proc *p, struct image_params *imgp __unused)
+{
+   	itimers_event_hook_exit(arg, p);
+}
+
 /* Clean up timers when some process events are being triggered. */
 static void
-itimers_event_hook(void *arg, struct proc *p)
+itimers_event_hook_exit(void *arg, struct proc *p)
 {
 	struct itimers *its;
 	struct itimer *it;

sys/kern/uipc_sem.c

@@ -71,6 +71,7 @@ static void sem_free(struct ksem *ksnew);
 static int sem_perm(struct thread *td, struct ksem *ks);
 static void sem_enter(struct proc *p, struct ksem *ks);
 static int sem_leave(struct proc *p, struct ksem *ks);
+static void sem_exechook(void *arg, struct proc *p, struct image_params *imgp);
 static void sem_exithook(void *arg, struct proc *p);
 static void sem_forkhook(void *arg, struct proc *p1, struct proc *p2,
     int flags);
@@ -919,7 +920,13 @@ race_lost:
 }
 
 static void
-sem_exithook(void *arg, struct proc *p)
+sem_exithook(void *arg, struct proc *p, struct image_params *imgp __unused)
+{
+   	sem_exechook(arg, p);   	
+}
+
+static void
+sem_exechook(void *arg, struct proc *p)
 {
 	struct ksem *ks, *ksnext;
 

sys/kern/vfs_aio.c

@@ -322,6 +322,7 @@ static int	aio_aqueue(struct thread *td, struct aiocb *job,
 			struct aioliojob *lio, int type, int osigev);
 static void	aio_physwakeup(struct buf *bp);
 static void	aio_proc_rundown(void *arg, struct proc *p);
+static void	aio_proc_rundown_exec(void *arg, struct proc *p, struct image_params *imgp);
 static int	aio_qphysio(struct proc *p, struct aiocblist *iocb);
 static void	biohelper(void *, int);
 static void	aio_daemon(void *param);
@@ -419,7 +420,7 @@ aio_onceonly(void)
 	aio_swake = &aio_swake_cb;
 	exit_tag = EVENTHANDLER_REGISTER(process_exit, aio_proc_rundown, NULL,
 	    EVENTHANDLER_PRI_ANY);
-	exec_tag = EVENTHANDLER_REGISTER(process_exec, aio_proc_rundown, NULL,
+	exec_tag = EVENTHANDLER_REGISTER(process_exec, aio_proc_rundown_exec, NULL,
 	    EVENTHANDLER_PRI_ANY);
 	kqueue_add_filteropts(EVFILT_AIO, &aio_filtops);
 	kqueue_add_filteropts(EVFILT_LIO, &lio_filtops);
@@ -630,6 +631,12 @@ aio_free_entry(struct aiocblist *aiocbe)
 	return (0);
 }
 
+static void
+aio_proc_rundown_exec(void *arg, struct proc *p, struct image_params *imgp __unused)
+{
+   	aio_proc_rundown(arg, p);
+}
+
 /*
  * Rundown the jobs for a given process.
  */

sys/sys/eventhandler.h

@@ -162,10 +162,11 @@ EVENTHANDLER_DECLARE(vm_lowmem, vm_lowmem_handler_t);
  * exec handlers are called with Giant, but that is by accident.
  */
 struct proc;
+struct image_params;
 
 typedef void (*exitlist_fn)(void *, struct proc *);
 typedef void (*forklist_fn)(void *, struct proc *, struct proc *, int);
-typedef void (*execlist_fn)(void *, struct proc *);
+typedef void (*execlist_fn)(void *, struct proc *, struct image_params *);
 
 EVENTHANDLER_DECLARE(process_exit, exitlist_fn);
 EVENTHANDLER_DECLARE(process_fork, forklist_fn);
@@ -174,4 +175,7 @@ EVENTHANDLER_DECLARE(process_exec, execlist_fn);
 typedef void (*uma_zone_chfn)(void *);
 EVENTHANDLER_DECLARE(nmbclusters_change, uma_zone_chfn);
 EVENTHANDLER_DECLARE(maxsockets_change, uma_zone_chfn);
+
+typedef void(*schedtail_fn)(void *, struct proc *);
+EVENTHANDLER_DECLARE(schedtail, schedtail_fn);
 #endif /* SYS_EVENTHANDLER_H */

sys/sys/imgact.h

@@ -63,6 +63,7 @@ struct image_params {
 	unsigned long ps_strings; /* PS_STRINGS for BSD/OS binaries */
 	size_t auxarg_size;
 	struct image_args *args;	/* system call arguments */
+	struct sysentvec *sysent;	/* system entry vector */
 };
 
 #ifdef _KERNEL