From 09baafb4710eb0c3da528e4f834f2054532a900d Mon Sep 17 00:00:00 2001
From: Dmitry Chagin <dchagin@FreeBSD.org>
Date: Sun, 24 May 2015 14:37:45 +0000
Subject: [PATCH] In preparation for switching linuxulator to the use the
 native 1:1 threads introduce kern_thr_alloc() which will be used later in the
 linux_clone().

Differential Revision:	https://reviews.freebsd.org/D1029
Reviewed by:	trasz
---
 sys/kern/kern_thr.c   | 29 +++++++++++++++++++----------
 sys/sys/syscallsubr.h |  1 +
 2 files changed, 20 insertions(+), 10 deletions(-)

diff --git a/sys/kern/kern_thr.c b/sys/kern/kern_thr.c
index e686b2278fd6..6cd215e5d2e3 100644
--- a/sys/kern/kern_thr.c
+++ b/sys/kern/kern_thr.c
@@ -162,12 +162,6 @@ create_thread(struct thread *td, mcontext_t *ctx,
 
 	p = td->td_proc;
 
-	/* Have race condition but it is cheap. */
-	if (p->p_numthreads >= max_threads_per_proc) {
-		++max_threads_hits;
-		return (EPROCLIM);
-	}
-
 	if (rtp != NULL) {
 		switch(rtp->type) {
 		case RTP_PRIO_REALTIME:
@@ -197,11 +191,9 @@ create_thread(struct thread *td, mcontext_t *ctx,
 #endif
 
 	/* Initialize our td */
-	newtd = thread_alloc(0);
-	if (newtd == NULL) {
-		error = ENOMEM;
+	error = kern_thr_alloc(p, 0, &newtd);
+	if (error)
 		goto fail;
-	}
 
 	cpu_set_upcall(newtd, td);
 
@@ -566,3 +558,20 @@ sys_thr_set_name(struct thread *td, struct thr_set_name_args *uap)
 	PROC_UNLOCK(p);
 	return (error);
 }
+
+int
+kern_thr_alloc(struct proc *p, int pages, struct thread **ntd)
+{
+
+	/* Have race condition but it is cheap. */
+	if (p->p_numthreads >= max_threads_per_proc) {
+		++max_threads_hits;
+		return (EPROCLIM);
+	}
+
+	*ntd = thread_alloc(pages);
+	if (*ntd == NULL)
+		return (ENOMEM);
+
+	return (0);
+}
diff --git a/sys/sys/syscallsubr.h b/sys/sys/syscallsubr.h
index 8d62eaa4608b..4954e465c934 100644
--- a/sys/sys/syscallsubr.h
+++ b/sys/sys/syscallsubr.h
@@ -214,6 +214,7 @@ int	kern_ktimer_settime(struct thread *td, int timer_id, int flags,
 int	kern_ktimer_gettime(struct thread *td, int timer_id,
 	    struct itimerspec *val);
 int	kern_ktimer_getoverrun(struct thread *td, int timer_id);
+int	kern_thr_alloc(struct proc *, int pages, struct thread **);
 int	kern_thr_exit(struct thread *td);
 int	kern_thr_new(struct thread *td, struct thr_param *param);
 int	kern_thr_suspend(struct thread *td, struct timespec *tsp);