Slight tweak to fork1() calling conventions. Add a third argument so

the caller can easily find the child proc struct.  fork(), rfork() etc
syscalls set p->p_retval[] themselves.  Simplify the SYSINIT_KT() code
and other kernel thread creators to not need to use pfind() to find the
child based on the pid.  While here, partly tidy up some of the fork1()
code for RF_SIGSHARE etc.

1 files changed, 49 insertions, 33 deletions

diff --git a/sys/kern/kern_fork.c b/sys/kern/kern_fork.c
index d5870b5..5ece79a 100644
--- a/sys/kern/kern_fork.c
+++ b/sys/kern/kern_fork.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)kern_fork.c	8.6 (Berkeley) 4/8/94
- * $Id: kern_fork.c,v 1.60 1999/04/28 01:04:27 luoqi Exp $
+ * $Id: kern_fork.c,v 1.61 1999/04/28 11:36:53 phk Exp $
  */
 
 #include "opt_ktrace.h"
@@ -92,8 +92,15 @@ fork(p, uap)
 	struct proc *p;
 	struct fork_args *uap;
 {
+	int error;
+	struct proc *p2;
 
-	return (fork1(p, RFFDG | RFPROC));
+	error = fork1(p, RFFDG | RFPROC, &p2);
+	if (error == 0) {
+		p->p_retval[0] = p2->p_pid;
+		p->p_retval[1] = 0;
+	}
+	return error;
 }
 
 /* ARGSUSED */
@@ -102,18 +109,31 @@ vfork(p, uap)
 	struct proc *p;
 	struct vfork_args *uap;
 {
+	int error;
+	struct proc *p2;
 
-	return (fork1(p, RFFDG | RFPROC | RFPPWAIT | (fast_vfork ? RFMEM : 0)));
+	error = fork1(p, RFFDG | RFPROC | RFPPWAIT | RFMEM, &p2);
+	if (error == 0) {
+		p->p_retval[0] = p2->p_pid;
+		p->p_retval[1] = 0;
+	}
+	return error;
 }
 
-/* ARGSUSED */
 int
 rfork(p, uap)
 	struct proc *p;
 	struct rfork_args *uap;
 {
+	int error;
+	struct proc *p2;
 
-	return (fork1(p, uap->flags));
+	error = fork1(p, uap->flags, &p2);
+	if (error == 0) {
+		p->p_retval[0] = p2->p_pid;
+		p->p_retval[1] = 0;
+	}
+	return error;
 }
 
 
@@ -121,12 +141,13 @@ int	nprocs = 1;		/* process 0 */
 static int nextpid = 0;
 
 int
-fork1(p1, flags)
-	register struct proc *p1;
+fork1(p1, flags, procp)
+	struct proc *p1;
 	int flags;
+	struct proc **procp;
 {
-	register struct proc *p2, *pptr;
-	register uid_t uid;
+	struct proc *p2, *pptr;
+	uid_t uid;
 	struct proc *newproc;
 	int count;
 	static int pidchecked = 0;
@@ -213,9 +234,9 @@ fork1(p1, flags)
 	/* Allocate new proc. */
 	newproc = zalloc(proc_zone);
 
-/*
- * Setup linkage for kernel based threading
- */
+	/*
+	 * Setup linkage for kernel based threading
+	 */
 	if((flags & RFTHREAD) != 0) {
 		newproc->p_peers = p1->p_peers;
 		p1->p_peers = newproc;
@@ -321,31 +342,28 @@ again:
 			struct sigacts *newsigacts;
 			int s;
 
-			if (p2->p_procsig->ps_refcnt != 2)
-				printf ("PID:%d Creating shared sigacts with procsig->ps_refcnt %d\n",
-					p2->p_pid, p2->p_procsig->ps_refcnt);
 			/* Create the shared sigacts structure */
-			MALLOC (newsigacts, struct sigacts *, sizeof (struct sigacts),
-				M_SUBPROC, M_WAITOK);
+			MALLOC(newsigacts, struct sigacts *,
+			    sizeof(struct sigacts), M_SUBPROC, M_WAITOK);
 			s = splhigh();
-			/* Set p_sigacts to the new shared structure.  Note that this
-			 * is updating p1->p_sigacts at the same time, since p_sigacts
-			 * is just a pointer to the shared p_procsig->ps_sigacts.
+			/*
+			 * Set p_sigacts to the new shared structure.
+			 * Note that this is updating p1->p_sigacts at the
+			 * same time, since p_sigacts is just a pointer to
+			 * the shared p_procsig->ps_sigacts.
 			 */
 			p2->p_sigacts  = newsigacts;
-			/* Copy in the values from the u area */
+			bcopy(&p1->p_addr->u_sigacts, p2->p_sigacts,
+			    sizeof(*p2->p_sigacts));
 			*p2->p_sigacts = p1->p_addr->u_sigacts;
-			splx (s);
+			splx(s);
 		}
 	} else {
-		MALLOC (p2->p_procsig, struct procsig *, sizeof(struct procsig),
-			M_SUBPROC, M_WAITOK);
-		bcopy(&p1->p_procsig->ps_begincopy, &p2->p_procsig->ps_begincopy,
-			(char *)&p1->p_procsig->ps_endcopy -
-			(char *)&p1->p_procsig->ps_begincopy);
+		MALLOC(p2->p_procsig, struct procsig *, sizeof(struct procsig),
+		    M_SUBPROC, M_WAITOK);
+		bcopy(p1->p_procsig, p2->p_procsig, sizeof(*p2->p_procsig));
 		p2->p_procsig->ps_refcnt = 1;
-		/* Note that we fill in the values of sigacts in vm_fork */
-		p2->p_sigacts = NULL;
+		p2->p_sigacts = NULL;	/* finished in vm_fork() */
 	}
 	if (flags & RFLINUXTHPN) 
 	        p2->p_sigparent = SIGUSR1;
@@ -467,11 +485,9 @@ again:
 		tsleep(p1, PWAIT, "ppwait", 0);
 
 	/*
-	 * Return child pid to parent process,
-	 * marking us as parent via p1->p_retval[1].
+	 * Return child proc pointer to parent.
 	 */
-	p1->p_retval[0] = p2->p_pid;
-	p1->p_retval[1] = 0;
+	*procp = p2;
 	return (0);
 }