Make the KERN_NPROCS and KERN_MAXPROC sysctl()s and the RLIMIT_NPROC rlimit

count processes instead of threads.  New sysctl()s KERN_NTHREADS and
KERN_MAXTHREAD count and limit threads.  The nprocs and maxproc kernel
variables are replaced by nprocess, maxprocess, nthreads, and maxthread.

ok tedu@ mikeb@

6 files changed, 63 insertions, 37 deletions

diff --git a/sys/kern/kern_exit.c b/sys/kern/kern_exit.c
index a715cd1f1b0..8b5fe9d463a 100644
--- a/sys/kern/kern_exit.c
+++ b/sys/kern/kern_exit.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_exit.c,v 1.110 2012/04/06 02:18:49 guenther Exp $	*/
+/*	$OpenBSD: kern_exit.c,v 1.111 2012/04/10 15:50:52 guenther Exp $	*/
 /*	$NetBSD: kern_exit.c,v 1.39 1996/04/22 01:38:25 christos Exp $	*/
 
 /*
@@ -584,13 +584,14 @@ proc_zap(struct proc *p)
 	if ((p->p_flag & P_THREAD) == 0)
 		leavepgrp(pr);
 	LIST_REMOVE(p, p_list);	/* off zombproc */
-	if ((p->p_flag & P_THREAD) == 0)
+	if ((p->p_flag & P_THREAD) == 0) {
 		LIST_REMOVE(pr, ps_sibling);
 
-	/*
-	 * Decrement the count of procs running with this uid.
-	 */
-	(void)chgproccnt(p->p_cred->p_ruid, -1);
+		/*
+		 * Decrement the count of procs running with this uid.
+		 */
+		(void)chgproccnt(p->p_cred->p_ruid, -1);
+	}
 
 	/*
 	 * Release reference to text vnode
@@ -611,8 +612,9 @@ proc_zap(struct proc *p)
 		crfree(pr->ps_cred->pc_ucred);
 		pool_put(&pcred_pool, pr->ps_cred);
 		pool_put(&process_pool, pr);
+		nprocesses--;
 	}
 
 	pool_put(&proc_pool, p);
-	nprocs--;
+	nthreads--;
 }
diff --git a/sys/kern/kern_fork.c b/sys/kern/kern_fork.c
index f7225155e47..8bf4a377777 100644
--- a/sys/kern/kern_fork.c
+++ b/sys/kern/kern_fork.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_fork.c,v 1.135 2012/03/23 15:51:26 guenther Exp $	*/
+/*	$OpenBSD: kern_fork.c,v 1.136 2012/04/10 15:50:52 guenther Exp $	*/
 /*	$NetBSD: kern_fork.c,v 1.29 1996/02/09 18:59:34 christos Exp $	*/
 
 /*
@@ -69,7 +69,8 @@
 # include <machine/tcb.h>
 #endif
 
-int	nprocs = 1;		/* process 0 */
+int	nprocesses = 1;		/* process 0 */
+int	nthreads = 1;		/* proc 0 */
 int	randompid;		/* when set to 1, pid's go random */
 pid_t	lastpid;
 struct	forkstat forkstat;
@@ -266,28 +267,46 @@ fork1(struct proc *curp, int exitsig, int flags, void *stack, pid_t *tidptr,
 	/*
 	 * Although process entries are dynamically created, we still keep
 	 * a global limit on the maximum number we will create. We reserve
-	 * the last 5 processes to root. The variable nprocs is the current
-	 * number of processes, maxproc is the limit.
+	 * the last 5 processes to root. The variable nprocesses is the
+	 * current number of processes, maxprocess is the limit.  Similar
+	 * rules for threads (struct proc): we reserve the last 5 to root;
+	 * the variable nthreads is the current number of procs, maxthread is
+	 * the limit.
 	 */
 	uid = curp->p_cred->p_ruid;
-	if ((nprocs >= maxproc - 5 && uid != 0) || nprocs >= maxproc) {
+	if ((nthreads >= maxthread - 5 && uid != 0) || nthreads >= maxthread) {
 		static struct timeval lasttfm;
 
 		if (ratecheck(&lasttfm, &fork_tfmrate))
 			tablefull("proc");
 		return (EAGAIN);
 	}
-	nprocs++;
+	nthreads++;
 
-	/*
-	 * Increment the count of procs running with this uid. Don't allow
-	 * a nonprivileged user to exceed their current limit.
-	 */
-	count = chgproccnt(uid, 1);
-	if (uid != 0 && count > curp->p_rlimit[RLIMIT_NPROC].rlim_cur) {
-		(void)chgproccnt(uid, -1);
-		nprocs--;
-		return (EAGAIN);
+	if ((flags & FORK_THREAD) == 0) {
+		if ((nprocesses >= maxprocess - 5 && uid != 0) ||
+		    nprocesses >= maxprocess) {
+			static struct timeval lasttfm;
+
+			if (ratecheck(&lasttfm, &fork_tfmrate))
+				tablefull("process");
+			nthreads--;
+			return (EAGAIN);
+		}
+		nprocesses++;
+
+		/*
+		 * Increment the count of processes running with
+		 * this uid.  Don't allow a nonprivileged user to
+		 * exceed their current limit.
+		 */
+		count = chgproccnt(uid, 1);
+		if (uid != 0 && count > curp->p_rlimit[RLIMIT_NPROC].rlim_cur) {
+			(void)chgproccnt(uid, -1);
+			nprocesses--;
+			nthreads--;
+			return (EAGAIN);
+		}
 	}
 
 	uaddr = uvm_km_kmemalloc_pla(kernel_map, uvm.kernel_object, USPACE,
@@ -296,7 +315,8 @@ fork1(struct proc *curp, int exitsig, int flags, void *stack, pid_t *tidptr,
 	    0, 0, USPACE/PAGE_SIZE);
 	if (uaddr == 0) {
 		chgproccnt(uid, -1);
-		nprocs--;
+		nprocesses--;
+		nthreads--;
 		return (ENOMEM);
 	}
 
diff --git a/sys/kern/kern_proc.c b/sys/kern/kern_proc.c
index 2bf3d8589b1..ad861c8e8af 100644
--- a/sys/kern/kern_proc.c
+++ b/sys/kern/kern_proc.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_proc.c,v 1.47 2011/09/18 23:20:54 miod Exp $	*/
+/*	$OpenBSD: kern_proc.c,v 1.48 2012/04/10 15:50:52 guenther Exp $	*/
 /*	$NetBSD: kern_proc.c,v 1.14 1996/02/09 18:59:41 christos Exp $	*/
 
 /*
@@ -86,9 +86,9 @@ procinit(void)
 	LIST_INIT(&zombproc);
 
 
-	pidhashtbl = hashinit(maxproc / 4, M_PROC, M_NOWAIT, &pidhash);
-	pgrphashtbl = hashinit(maxproc / 4, M_PROC, M_NOWAIT, &pgrphash);
-	uihashtbl = hashinit(maxproc / 16, M_PROC, M_NOWAIT, &uihash);
+	pidhashtbl = hashinit(maxthread / 4, M_PROC, M_NOWAIT, &pidhash);
+	pgrphashtbl = hashinit(maxprocess / 4, M_PROC, M_NOWAIT, &pgrphash);
+	uihashtbl = hashinit(maxprocess / 16, M_PROC, M_NOWAIT, &uihash);
 	if (!pidhashtbl || !pgrphashtbl || !uihashtbl)
 		panic("procinit: malloc");
 
diff --git a/sys/kern/kern_prot.c b/sys/kern/kern_prot.c
index 95a7c0a2401..c4a833de12e 100644
--- a/sys/kern/kern_prot.c
+++ b/sys/kern/kern_prot.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_prot.c,v 1.52 2012/02/20 22:23:39 guenther Exp $	*/
+/*	$OpenBSD: kern_prot.c,v 1.53 2012/04/10 15:50:52 guenther Exp $	*/
 /*	$NetBSD: kern_prot.c,v 1.33 1996/02/09 18:59:42 christos Exp $	*/
 
 /*
@@ -391,8 +391,8 @@ sys_setresuid(struct proc *p, void *v, register_t *retval)
 		/*
 		 * Transfer proc count to new user.
 		 */
-		(void)chgproccnt(pc->p_ruid, -p->p_p->ps_refcnt);
-		(void)chgproccnt(ruid, p->p_p->ps_refcnt);
+		(void)chgproccnt(pc->p_ruid, -1);
+		(void)chgproccnt(ruid, 1);
 		pc->p_ruid = ruid;
 	}
 	if (euid != (uid_t)-1 && euid != pc->pc_ucred->cr_uid) {
@@ -596,8 +596,8 @@ sys_setuid(struct proc *p, void *v, register_t *retval)
 		 * Transfer proc count to new user.
 		 */
 		if (uid != pc->p_ruid) {
-			(void)chgproccnt(pc->p_ruid, -p->p_p->ps_refcnt);
-			(void)chgproccnt(uid, p->p_p->ps_refcnt);
+			(void)chgproccnt(pc->p_ruid, -1);
+			(void)chgproccnt(uid, 1);
 		}
 		pc->p_ruid = uid;
 		pc->p_svuid = uid;
diff --git a/sys/kern/kern_resource.c b/sys/kern/kern_resource.c
index ab199d4401e..995b3db15ef 100644
--- a/sys/kern/kern_resource.c
+++ b/sys/kern/kern_resource.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_resource.c,v 1.39 2012/03/23 15:51:26 guenther Exp $	*/
+/*	$OpenBSD: kern_resource.c,v 1.40 2012/04/10 15:50:52 guenther Exp $	*/
 /*	$NetBSD: kern_resource.c,v 1.38 1996/10/23 07:19:38 matthias Exp $	*/
 
 /*-
@@ -264,7 +264,7 @@ dosetrlimit(struct proc *p, u_int which, struct rlimit *limp)
 		maxlim = maxfiles;
 		break;
 	case RLIMIT_NPROC:
-		maxlim = maxproc;
+		maxlim = maxprocess;
 		break;
 	default:
 		maxlim = RLIM_INFINITY;
diff --git a/sys/kern/kern_sysctl.c b/sys/kern/kern_sysctl.c
index 8651cf8514a..e577f6b1e35 100644
--- a/sys/kern/kern_sysctl.c
+++ b/sys/kern/kern_sysctl.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_sysctl.c,v 1.218 2012/03/28 16:01:30 guenther Exp $	*/
+/*	$OpenBSD: kern_sysctl.c,v 1.219 2012/04/10 15:50:52 guenther Exp $	*/
 /*	$NetBSD: kern_sysctl.c,v 1.17 1996/05/20 17:49:05 mrg Exp $	*/
 
 /*-
@@ -316,7 +316,7 @@ kern_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
 	case KERN_MAXVNODES:
 		return(sysctl_int(oldp, oldlenp, newp, newlen, &maxvnodes));
 	case KERN_MAXPROC:
-		return (sysctl_int(oldp, oldlenp, newp, newlen, &maxproc));
+		return (sysctl_int(oldp, oldlenp, newp, newlen, &maxprocess));
 	case KERN_MAXFILES:
 		return (sysctl_int(oldp, oldlenp, newp, newlen, &maxfiles));
 	case KERN_NFILES:
@@ -401,6 +401,10 @@ kern_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
 		return (sysctl_rdint(oldp, oldlenp, newp, MAXPARTITIONS));
 	case KERN_RAWPARTITION:
 		return (sysctl_rdint(oldp, oldlenp, newp, RAW_PART));
+	case KERN_MAXTHREAD:
+		return (sysctl_int(oldp, oldlenp, newp, newlen, &maxthread));
+	case KERN_NTHREADS:
+		return (sysctl_rdint(oldp, oldlenp, newp, nthreads));
 	case KERN_SOMAXCONN:
 		return (sysctl_int(oldp, oldlenp, newp, newlen, &somaxconn));
 	case KERN_SOMINCONN:
@@ -494,7 +498,7 @@ kern_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
 	case KERN_CCPU:
 		return (sysctl_rdint(oldp, oldlenp, newp, ccpu));
 	case KERN_NPROCS:
-		return (sysctl_rdint(oldp, oldlenp, newp, nprocs));
+		return (sysctl_rdint(oldp, oldlenp, newp, nprocesses));
 	case KERN_POOL:
 		return (sysctl_dopool(name + 1, namelen - 1, oldp, oldlenp));
 	case KERN_STACKGAPRANDOM: