1 files changed, 120 insertions, 0 deletions
diff --git a/sys/kern/kern_dtrace.c b/sys/kern/kern_dtrace.c
new file mode 100644
index 0000000..71efe1c
--- /dev/null
+++ b/sys/kern/kern_dtrace.c
@@ -0,0 +1,120 @@
+/*-
+ * Copyright (c) 2007-2008 John Birrell <jb@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include "opt_kdb.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/eventhandler.h>
+#include <sys/kdb.h>
+#include <sys/kernel.h>
+#include <sys/malloc.h>
+#include <sys/proc.h>
+#include <sys/dtrace_bsd.h>
+
+#define KDTRACE_PROC_SIZE	64
+#define KDTRACE_PROC_ZERO	8
+#define	KDTRACE_THREAD_SIZE	256
+#define	KDTRACE_THREAD_ZERO	64
+
+MALLOC_DEFINE(M_KDTRACE, "kdtrace", "DTrace hooks");
+
+/* Return the DTrace process data size compiled in the kernel hooks. */
+size_t
+kdtrace_proc_size()
+{
+	return(KDTRACE_PROC_SIZE);
+}
+
+static void
+kdtrace_proc_ctor(void *arg __unused, struct proc *p)
+{
+	p->p_dtrace = malloc(KDTRACE_PROC_SIZE, M_KDTRACE, M_WAITOK);
+
+	bzero(p->p_dtrace, KDTRACE_PROC_ZERO);
+}
+
+static void
+kdtrace_proc_dtor(void *arg __unused, struct proc *p)
+{
+	if (p->p_dtrace != NULL) {
+		free(p->p_dtrace, M_KDTRACE);
+		p->p_dtrace = NULL;
+	}
+}
+
+/* Return the DTrace thread data size compiled in the kernel hooks. */
+size_t
+kdtrace_thread_size()
+{
+	return(KDTRACE_THREAD_SIZE);
+}
+
+static void
+kdtrace_thread_ctor(void *arg __unused, struct thread *td)
+{
+	td->td_dtrace = malloc(KDTRACE_THREAD_SIZE, M_KDTRACE, M_WAITOK);
+
+	bzero(td->td_dtrace, KDTRACE_THREAD_ZERO);
+}
+
+static void
+kdtrace_thread_dtor(void *arg __unused, struct thread *td)
+{
+	if (td->td_dtrace != NULL) {
+		free(td->td_dtrace, M_KDTRACE);
+		td->td_dtrace = NULL;
+	}
+}
+
+/*
+ *  Initialise the kernel DTrace hooks.
+ */
+static void
+init_dtrace(void *dummy __unused)
+{
+	EVENTHANDLER_REGISTER(process_ctor, kdtrace_proc_ctor, NULL, EVENTHANDLER_PRI_ANY);
+	EVENTHANDLER_REGISTER(process_dtor, kdtrace_proc_dtor, NULL, EVENTHANDLER_PRI_ANY);
+	EVENTHANDLER_REGISTER(thread_ctor, kdtrace_thread_ctor, NULL, EVENTHANDLER_PRI_ANY);
+	EVENTHANDLER_REGISTER(thread_dtor, kdtrace_thread_dtor, NULL, EVENTHANDLER_PRI_ANY);
+}
+
+SYSINIT(kdtrace, SI_SUB_KDTRACE, SI_ORDER_FIRST, init_dtrace, NULL);
+
+#ifndef KDB
+/*
+ * This is a stub for the kernel debugger for the DTrace actions to call
+ * when the kernel has been built without KDB.
+ */
+void
+kdb_enter(const char *why, const char *msg)
+{
+	printf("Cannot enter kernel debugger - No KDB in kernel.\n%s - %s\n", why, msg);
+}
+#endif