Support for kernels built with CONFIG_FRAME_POINTER

10 files changed, 36 insertions, 9 deletions

diff --git a/runtime/ChangeLog b/runtime/ChangeLog
index d9ea4474..7c6dbbea 100644
--- a/runtime/ChangeLog
+++ b/runtime/ChangeLog
@@ -1,3 +1,12 @@
+2008-03-30  Martin Hunt  <hunt@redhat.com>
+
+	* runtime.h (STP_USE_FRAME_POINTER): Define when frame pointers
+	are available in the kernel and can be used.
+	* stack-arm.c: Use STP_USE_FRAME_POINTER.
+	* stack-i386.c: Ditto.
+	* unwind/i386.h: Ditto.
+	* unwind/x86_64.h: Ditto.
+
 2008-03-28  Martin Hunt  <hunt@redhat.com>
 
 	* copy.c (_stp_read_address): New function. Safely read 
diff --git a/runtime/copy.c b/runtime/copy.c
index 8891f171..6bb22762 100644
--- a/runtime/copy.c
+++ b/runtime/copy.c
@@ -1,6 +1,6 @@
 /* -*- linux-c -*- 
  * Copy from user space functions
- * Copyright (C) 2005, 2006, 2007 Red Hat Inc.
+ * Copyright (C) 2005-2008 Red Hat Inc.
  * Copyright (C) 2005 Intel Corporation.
  *
  * This file is part of systemtap, and is free software.  You can
diff --git a/runtime/runtime.h b/runtime/runtime.h
index b9a9c778..6d8d9dc9 100644
--- a/runtime/runtime.h
+++ b/runtime/runtime.h
@@ -70,6 +70,13 @@ static struct
 #define MAXSTRINGLEN 128
 #endif
 
+#ifdef CONFIG_FRAME_POINTER
+/* Just because frame pointers are available does not mean we can trust them. */
+#if defined (__i386__) || defined (__arm__)
+#define STP_USE_FRAME_POINTER
+#endif
+#endif
+
 #include "alloc.c"
 #include "print.c"
 #include "string.c"
diff --git a/runtime/stack-arm.c b/runtime/stack-arm.c
index 0c8ce450..9b0b772d 100644
--- a/runtime/stack-arm.c
+++ b/runtime/stack-arm.c
@@ -33,7 +33,7 @@ static int __init find_str_pc_offset(void)
 
 static void __stp_stack_print (struct pt_regs *regs, int verbose, int levels)
 {
-#if defined(CONFIG_FRAME_POINTER)
+#ifdef STP_USE_FRAME_POINTER
 	int		pc_offset = find_str_pc_offset();
 	unsigned long	*fp = (unsigned long *)regs->ARM_fp;
 	unsigned long	*next_fp, *pc;
@@ -68,5 +68,5 @@ static void __stp_stack_print (struct pt_regs *regs, int verbose, int levels)
 
 		fp = next_fp;
 	}
-#endif
+#endif /* STP_USE_FRAME_POINTER */
 }
diff --git a/runtime/stack-i386.c b/runtime/stack-i386.c
index 11919b29..20c8eda5 100644
--- a/runtime/stack-i386.c
+++ b/runtime/stack-i386.c
@@ -32,7 +32,7 @@ static void __stp_stack_print (struct pt_regs *regs, int verbose, int levels)
 	unsigned long *stack = (unsigned long *)&REG_SP(regs);
 	unsigned long context = (unsigned long)stack & ~(THREAD_SIZE - 1);
 
-#ifdef	CONFIG_FRAME_POINTER
+#ifdef	STP_USE_FRAME_POINTER
 	/* FIXME: need to use _stp_func_print() and safe copy */
 	unsigned long addr;
 	
@@ -72,5 +72,5 @@ static void __stp_stack_print (struct pt_regs *regs, int verbose, int levels)
 			_stp_stack_print_fallback(context, UNW_SP(&info), verbose);
 		break;
 	}
-#endif /* CONFIG_FRAME_POINTER */
+#endif /* STP_USE_FRAME_POINTER */
 }
diff --git a/runtime/transport/ChangeLog b/runtime/transport/ChangeLog
index 2db40a12..b55657e9 100644
--- a/runtime/transport/ChangeLog
+++ b/runtime/transport/ChangeLog
@@ -1,3 +1,8 @@
+2008-03-30  Martin Hunt  <hunt@redhat.com>
+
+	* symbols.c (_stp_init_modules): If using frames, don't
+	request unwind info.
+
 2008-03-25  Martin Hunt  <hunt@redhat.com>
 
 	* control.c (_stp_ctl_write_dbug): Insert missing break.
diff --git a/runtime/transport/symbols.c b/runtime/transport/symbols.c
index 83a3a635..118d5693 100644
--- a/runtime/transport/symbols.c
+++ b/runtime/transport/symbols.c
@@ -581,7 +581,10 @@ static int _stp_init_modules(void)
 	/* unlocks the list */
 	modules_op->stop(NULL, NULL);
 
-#ifndef CONFIG_FRAME_POINTER
+#ifdef STP_USE_FRAME_POINTER
+	/* done with modules, now go */
+	_stp_ctl_send(STP_TRANSPORT, NULL, 0);
+#else
 	/* now that we have all the modules, ask for their unwind info */
 	{
 		unsigned long flags;
diff --git a/runtime/transport/transport.c b/runtime/transport/transport.c
index aa96a50e..8f59584d 100644
--- a/runtime/transport/transport.c
+++ b/runtime/transport/transport.c
@@ -259,7 +259,7 @@ int _stp_transport_init(void)
 		goto err3;
 	
 	_stp_transport_state = 1;
-	
+
 	dbug_trans(1, "calling init_kernel_symbols\n");
 	if (_stp_init_kernel_symbols() < 0)
 		goto err4;
diff --git a/runtime/unwind/i386.h b/runtime/unwind/i386.h
index cb2efab7..354807a0 100644
--- a/runtime/unwind/i386.h
+++ b/runtime/unwind/i386.h
@@ -30,7 +30,7 @@ struct unwind_frame_info
 
 #define UNW_PC(frame)        (frame)->regs.eip
 #define UNW_SP(frame)        (frame)->regs.esp
-#ifdef CONFIG_FRAME_POINTER
+#ifdef STP_USE_FRAME_POINTER
 #define UNW_FP(frame)        (frame)->regs.ebp
 #define FRAME_RETADDR_OFFSET 4
 #define FRAME_LINK_OFFSET    0
diff --git a/runtime/unwind/x86_64.h b/runtime/unwind/x86_64.h
index 6e6e521f..48838490 100644
--- a/runtime/unwind/x86_64.h
+++ b/runtime/unwind/x86_64.h
@@ -35,13 +35,16 @@ struct unwind_frame_info
 
 #define UNW_PC(frame)        (frame)->regs.rip
 #define UNW_SP(frame)        (frame)->regs.rsp
-#ifdef CONFIG_FRAME_POINTER
+
+#if 0 /* STP_USE_FRAME_POINTER */
+/* Frame pointers not implemented in x86_64 currently */
 #define UNW_FP(frame)        (frame)->regs.rbp
 #define FRAME_RETADDR_OFFSET 8
 #define FRAME_LINK_OFFSET    0
 #define STACK_BOTTOM(tsk)    (((tsk)->thread.rsp0 - 1) & ~(THREAD_SIZE - 1))
 #define STACK_TOP(tsk)       ((tsk)->thread.rsp0)
 #endif
+
 /* Might need to account for the special exception and interrupt handling
    stacks here, since normally
 	EXCEPTION_STACK_ORDER < THREAD_ORDER < IRQSTACK_ORDER,