PERFORCE change 182536 for review

[John Baldwin]

http://p4web.freebsd.org/@@182536?ac=10

Change 182536 by jhb at jhb_fiver on 2010/08/17 19:51:45

	Move ktrace logic for fork() and exec() into kern_ktrace.c.

Affected files ...

.. //depot/projects/smpng/sys/kern/kern_exec.c#131 edit
.. //depot/projects/smpng/sys/kern/kern_fork.c#126 edit
.. //depot/projects/smpng/sys/kern/kern_ktrace.c#74 edit
.. //depot/projects/smpng/sys/sys/ktrace.h#18 edit

Differences ...

==== //depot/projects/smpng/sys/kern/kern_exec.c#131 (text+ko) ====

@@ -661,16 +661,8 @@
 		setsugid(p);
 
 #ifdef KTRACE
-		if (p->p_tracevp != NULL &&
-		    priv_check_cred(oldcred, PRIV_DEBUG_DIFFCRED, 0)) {
-			mtx_lock(&ktrace_mtx);
-			p->p_traceflag = 0;
-			tracevp = p->p_tracevp;
-			p->p_tracevp = NULL;
-			tracecred = p->p_tracecred;
-			p->p_tracecred = NULL;
-			mtx_unlock(&ktrace_mtx);
-		}
+		if (priv_check_cred(oldcred, PRIV_DEBUG_DIFFCRED, 0))
+			ktrprocexec(p, &tracecred, &tracevp);
 #endif
 		/*
 		 * Close any file descriptors 0..2 that reference procfs,

==== //depot/projects/smpng/sys/kern/kern_fork.c#126 (text+ko) ====

@@ -645,21 +645,7 @@
 	callout_init(&p2->p_itcallout, CALLOUT_MPSAFE);
 
 #ifdef KTRACE
-	/*
-	 * Copy traceflag and tracefile if enabled.
-	 */
-	mtx_lock(&ktrace_mtx);
-	KASSERT(p2->p_tracevp == NULL, ("new process has a ktrace vnode"));
-	if (p1->p_traceflag & KTRFAC_INHERIT) {
-		p2->p_traceflag = p1->p_traceflag;
-		if ((p2->p_tracevp = p1->p_tracevp) != NULL) {
-			VREF(p2->p_tracevp);
-			KASSERT(p1->p_tracecred != NULL,
-			    ("ktrace vnode with no cred"));
-			p2->p_tracecred = crhold(p1->p_tracecred);
-		}
-	}
-	mtx_unlock(&ktrace_mtx);
+	ktrprocfork(p1, p2);
 #endif
 
 	/*

==== //depot/projects/smpng/sys/kern/kern_ktrace.c#74 (text+ko) ====

@@ -126,7 +126,7 @@
     0, "Maximum size of genio event payload");
 
 static int print_message = 1;
-struct mtx ktrace_mtx;
+static struct mtx ktrace_mtx;
 static struct sx ktrace_sx;
 
 static void ktrace_init(void *dummy);
@@ -467,7 +467,22 @@
 }
 
 /*
- * When a process exits drain per-process asynchronous trace records
+ * When a setuid process execs, disable tracing.
+ *
+ * XXX: We toss any pending asynchronous records.
+ */
+void
+ktrprocexec(struct proc *p, struct ucred **uc, struct vnode **vp)
+{
+
+	PROC_LOCK_ASSERT(p, MA_OWNED);
+	mtx_lock(&ktrace_mtx);
+	ktr_freeproc(p, uc, vp);
+	mtx_unlock(&ktrace_mtx);
+}
+
+/*
+ * When a process exits, drain per-process asynchronous trace records
  * and disable tracing.
  */
 void
@@ -502,6 +517,29 @@
 }
 
 /*
+ * When a process forks, enable tracing in the new process if needed.
+ */
+void
+ktrprocfork(struct proc *p1, struct proc *p2)
+{
+
+	PROC_LOCK_ASSERT(p1, MA_OWNED);
+	PROC_LOCK_ASSERT(p2, MA_OWNED);
+	mtx_lock(&ktrace_mtx);
+	KASSERT(p2->p_tracevp == NULL, ("new process has a ktrace vnode"));
+	if (p1->p_traceflag & KTRFAC_INHERIT) {
+		p2->p_traceflag = p1->p_traceflag;
+		if ((p2->p_tracevp = p1->p_tracevp) != NULL) {
+			VREF(p2->p_tracevp);
+			KASSERT(p1->p_tracecred != NULL,
+			    ("ktrace vnode with no cred"));
+			p2->p_tracecred = crhold(p1->p_tracecred);
+		}
+	}
+	mtx_unlock(&ktrace_mtx);
+}
+
+/*
  * When a thread returns, drain any asynchronous records generated by the
  * system call.
  */

==== //depot/projects/smpng/sys/sys/ktrace.h#18 (text+ko) ====

@@ -73,10 +73,6 @@
 	if (KTRCHECKDRAIN(td))						\
 		ktruserret(td);						\
 } while (0)
-#define	KTRPROCEXIT(td) do {						\
-	if (KTRCHECKDRAIN(td))						\
-		ktrprocexit(td);					\
-} while (0)
 
 /*
  * ktrace record types
@@ -195,8 +191,6 @@
 #define	KTRFAC_DROP	0x20000000	/* last event was dropped */
 
 #ifdef	_KERNEL
-extern struct mtx ktrace_mtx;
-
 void	ktrnamei(char *);
 void	ktrcsw(int, int);
 void	ktrpsig(int, sig_t, sigset_t *, int);
@@ -204,7 +198,9 @@
 void	ktrsyscall(int, int narg, register_t args[]);
 void	ktrsysctl(int *name, u_int namelen);
 void	ktrsysret(int, int, register_t);
+void	ktrprocexec(struct proc *, struct ucred **, struct vnode **);
 void	ktrprocexit(struct thread *);
+void	ktrprocfork(struct proc *, struct proc *);
 void	ktruserret(struct thread *);
 void	ktrstruct(const char *, void *, size_t);
 #define ktrsockaddr(s) \