From 7f6a57605ca49fb28b122af7db27384177a5ba5f Mon Sep 17 00:00:00 2001
From: Guanqun Lu <Guanqun.Lu@Gmail.com>
Date: Sat, 8 Mar 2008 22:01:47 +0800
Subject: [PATCH] enhanced backtrace output

Signed-off-by: Guanqun Lu <Guanqun.Lu@Gmail.com>
---
 kern/kdebug.c  | 15 +++++++++++++--
 kern/monitor.c | 10 ++++++++++
 kern/pmap.c    |  3 ++-
 3 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/kern/kdebug.c b/kern/kdebug.c
index 89833db..7e2c9e2 100644
--- a/kern/kdebug.c
+++ b/kern/kdebug.c
@@ -108,7 +108,7 @@ debuginfo_eip(uintptr_t addr, struct Eipdebuginfo *info)
 {
 	const struct Stab *stabs, *stab_end;
 	const char *stabstr, *stabstr_end;
-	int lfile, rfile, lfun, rfun, lline, rline;
+	int lfile, rfile, lfun, rfun, lline, rline, i;
 
 	// Initialize *info
 	info->eip_file = "<unknown>";
@@ -181,8 +181,12 @@ debuginfo_eip(uintptr_t addr, struct Eipdebuginfo *info)
 	//	Look at the STABS documentation and <inc/stab.h> to find
 	//	which one.
 	// Your code here.
+	lline = lfun;
+	rline = rfun;
+	stab_binsearch(stabs, &lline, &rline, N_SLINE, addr);
+	if (lline <= rline)
+		info->eip_line = stabs[lline].n_desc;
 
-	
 	// Search backwards from the line number for the relevant filename
 	// stab.
 	// We can't just use the "lfile" stab because inlined functions
@@ -200,6 +204,13 @@ debuginfo_eip(uintptr_t addr, struct Eipdebuginfo *info)
 	// or 0 if there was no containing function.
 	// Your code here.
 
+	// but it seems that it is not used?
+	i = 0;
+	while (lline <= rline && stabs[lline].n_type == N_PSYM) {
+		lline++;
+		i++;
+	}
+	info->eip_fn_narg = i;
 	
 	return 0;
 }
diff --git a/kern/monitor.c b/kern/monitor.c
index 5fefbfb..36a5af6 100644
--- a/kern/monitor.c
+++ b/kern/monitor.c
@@ -24,6 +24,7 @@ struct Command {
 static struct Command commands[] = {
 	{ "help", "Display this list of commands", mon_help },
 	{ "kerninfo", "Display information about the kernel", mon_kerninfo },
+	{ "backtrace", "Display the backtrace information", mon_backtrace },
 };
 #define NCOMMANDS (sizeof(commands)/sizeof(commands[0]))
 
@@ -60,6 +61,7 @@ int
 mon_backtrace(int argc, char **argv, struct Trapframe *tf)
 {
 	// Your code here.
+	struct Eipdebuginfo eip_debug;
 	unsigned int *ebp, *eip;
 	int i;
 
@@ -67,6 +69,14 @@ mon_backtrace(int argc, char **argv, struct Trapframe *tf)
 	eip = (unsigned int *)read_eip();
 	cprintf("Stack backtrace:\n");
 	while (ebp) {
+		// enhanced backtrace output
+		debuginfo_eip((uintptr_t)eip, &eip_debug);
+		cprintf("%s:%d: ", eip_debug.eip_file, eip_debug.eip_line);
+		for (i = 0; i < eip_debug.eip_fn_namelen; i++)
+			cprintf("%c", eip_debug.eip_fn_name[i]);
+		cprintf("+%x\n",
+				(unsigned int)eip - (unsigned int)eip_debug.eip_fn_addr);
+
 		eip = (unsigned int *)*(ebp + 1);
 
 		// basic backtrace output
diff --git a/kern/pmap.c b/kern/pmap.c
index 065b317..37c187a 100644
--- a/kern/pmap.c
+++ b/kern/pmap.c
@@ -445,6 +445,7 @@ page_init(void)
 	// Change the code to reflect this.
 	struct Page *ppage;
 	unsigned int i;
+	extern char _start[];
 
 	LIST_INIT(&page_free_list);
 	for (i = 0; i < npage; i++) {
@@ -462,7 +463,7 @@ page_init(void)
 	}
 
 	// reserve the kernel image and data structures allocated
-	for (i = 0xf0100000; i < (unsigned int)boot_freemem; i += PGSIZE) {
+	for (i = (unsigned int)_start; i < (unsigned int)boot_freemem; i += PGSIZE) {
 		ppage = pa2page(PADDR(i));
 		LIST_REMOVE(ppage, pp_link);
 	}
-- 
2.11.4.GIT