Kernel and hwpmc(4) support for callchain capture.

Sponsored by:	FreeBSD Foundation and Google Inc.

1 files changed, 13 insertions, 0 deletions

diff --git a/sys/kern/subr_trap.c b/sys/kern/subr_trap.c
index 355faf2..d8168af 100644
--- a/sys/kern/subr_trap.c
+++ b/sys/kern/subr_trap.c
@@ -2,10 +2,14 @@
  * Copyright (C) 1994, David Greenman
  * Copyright (c) 1990, 1993
  *	The Regents of the University of California.  All rights reserved.
+ * Copyright (c) 2007 The FreeBSD Foundation
  *
  * This code is derived from software contributed to Berkeley by
  * the University of Utah, and William Jolitz.
  *
+ * Portions of this software were developed by A. Joseph Koshy under
+ * sponsorship from the FreeBSD Foundation and Google, Inc.
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
@@ -40,6 +44,7 @@
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
+#include "opt_hwpmc_hooks.h"
 #include "opt_ktrace.h"
 #include "opt_mac.h"
 #ifdef __i386__
@@ -52,6 +57,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/kernel.h>
 #include <sys/lock.h>
 #include <sys/mutex.h>
+#include <sys/pmckern.h>
 #include <sys/proc.h>
 #include <sys/ktr.h>
 #include <sys/resourcevar.h>
@@ -201,6 +207,13 @@ ast(struct trapframe *framep)
 		td->td_profil_ticks = 0;
 		td->td_pflags &= ~TDP_OWEUPC;
 	}
+#if defined(HWPMC_HOOKS)
+	if (td->td_pflags & TDP_CALLCHAIN) {
+		PMC_CALL_HOOK_UNLOCKED(td, PMC_FN_USER_CALLCHAIN,
+		    (void *) framep);
+		td->td_pflags &= ~TDP_CALLCHAIN;
+	}
+#endif
 	if (flags & TDF_ALRMPEND) {
 		PROC_LOCK(p);
 		psignal(p, SIGVTALRM);