svn commit: r326701 - stable/11/sys/cddl/contrib/opensolaris/uts/common/dtrace

[Mark Johnston]

Author: markj
Date: Fri Dec  8 18:04:43 2017
New Revision: 326701
URL: https://svnweb.freebsd.org/changeset/base/326701

Log:
  MFC r326134:
  Duplicate helpers after disabling inherited tracepoints during a fork.

Modified:
  stable/11/sys/cddl/contrib/opensolaris/uts/common/dtrace/fasttrap.c
Directory Properties:
  stable/11/   (props changed)

Modified: stable/11/sys/cddl/contrib/opensolaris/uts/common/dtrace/fasttrap.c
==============================================================================
--- stable/11/sys/cddl/contrib/opensolaris/uts/common/dtrace/fasttrap.c	Fri Dec  8 17:52:53 2017	(r326700)
+++ stable/11/sys/cddl/contrib/opensolaris/uts/common/dtrace/fasttrap.c	Fri Dec  8 18:04:43 2017	(r326701)
@@ -600,8 +600,8 @@ fasttrap_fork(proc_t *p, proc_t *cp)
 	pid_t ppid = p->p_pid;
 	int i;
 
-#ifdef illumos
 	ASSERT(curproc == p);
+#ifdef illumos
 	ASSERT(p->p_proc_flag & P_PR_LOCK);
 #else
 	PROC_LOCK_ASSERT(p, MA_OWNED);
@@ -609,26 +609,15 @@ fasttrap_fork(proc_t *p, proc_t *cp)
 #ifdef illumos
 	ASSERT(p->p_dtrace_count > 0);
 #else
-	if (p->p_dtrace_helpers) {
-		/*
-		 * dtrace_helpers_duplicate() allocates memory.
-		 */
-		_PHOLD(cp);
-		PROC_UNLOCK(p);
-		PROC_UNLOCK(cp);
-		dtrace_helpers_duplicate(p, cp);
-		PROC_LOCK(cp);
-		PROC_LOCK(p);
-		_PRELE(cp);
-	}
 	/*
 	 * This check is purposely here instead of in kern_fork.c because,
 	 * for legal resons, we cannot include the dtrace_cddl.h header
 	 * inside kern_fork.c and insert if-clause there.
 	 */
-	if (p->p_dtrace_count == 0)
+	if (p->p_dtrace_count == 0 && p->p_dtrace_helpers == NULL)
 		return;
 #endif
+
 	ASSERT(cp->p_dtrace_count == 0);
 
 	/*
@@ -657,6 +646,8 @@ fasttrap_fork(proc_t *p, proc_t *cp)
 	_PHOLD(cp);
 	PROC_UNLOCK(cp);
 	PROC_UNLOCK(p);
+	if (p->p_dtrace_count == 0)
+		goto dup_helpers;
 #endif
 
 	/*
@@ -710,6 +701,9 @@ fasttrap_fork(proc_t *p, proc_t *cp)
 	mutex_enter(&cp->p_lock);
 	sprunlock(cp);
 #else
+dup_helpers:
+	if (p->p_dtrace_helpers != NULL)
+		dtrace_helpers_duplicate(p, cp);
 	PROC_LOCK(p);
 	PROC_LOCK(cp);
 	_PRELE(cp);