Add better stack tracing technology (now uses kernel memory map!)

7 files changed, 100 insertions, 35 deletions

diff --git a/src/kernel/core/idt.c b/src/kernel/core/idt.c
index d963b4d..457e5ae 100644
--- a/src/kernel/core/idt.c
+++ b/src/kernel/core/idt.c
@@ -91,7 +91,8 @@ static isr_handler_t ex_handlers[32] = {0};
 
 /*	Called in interrupt.s when an exception fires (interrupt 0 to 31) */
 void idt_ex_handler(registers_t *regs) {
-	dbg_printf("ex%d.", regs->int_no);
+	/*dbg_printf("ex%d.", regs->int_no);*/
+
 	if (ex_handlers[regs->int_no] != 0) {
 		ex_handlers[regs->int_no](regs);
 	} else {
@@ -115,7 +116,7 @@ void idt_ex_handler(registers_t *regs) {
 void idt_irq_handler(registers_t *regs) {
 	int st = enter_critical(CL_EXCL);	// if someone tries to yield(), an assert will fail
 
-	dbg_printf("irq%d.", regs->err_code);
+	if (regs->err_code != 0) dbg_printf("irq%d.", regs->err_code);
 
 	if (regs->err_code > 7) {
 		outb(0xA0, 0x20);
@@ -278,15 +279,8 @@ void dbg_dump_registers(registers_t *regs) {
 	dbg_printf("| EIP: 0x%p   CS : 0x%p   DS : 0x%p   SS : 0x%p\n", regs->eip, regs->cs, regs->ds, regs->ss);
 	dbg_printf("| EFl: 0x%p   I# : 0x%p   Err: 0x%p\n", regs->eflags, regs->int_no, regs->err_code);
 	dbg_printf("- Stack trace:\n");
-
-	uint32_t ebp = regs->ebp, eip = regs->eip;
-	int i = 0;
-	while (ebp >= K_HIGHHALF_ADDR && eip >= K_HIGHHALF_ADDR && i++ < 10) {
-		dbg_printf("| 0x%p	EIP: 0x%p\n", ebp, eip);
-		uint32_t *d = (uint32_t*)ebp;
-		ebp = d[0];
-		eip = d[1];
-	}
+	
+	kernel_stacktrace(regs->ebp, regs->eip);
 
 	dbg_printf("\\\n");
 }
diff --git a/src/kernel/core/kmain.c b/src/kernel/core/kmain.c
index 005f449..3ee2238 100644
--- a/src/kernel/core/kmain.c
+++ b/src/kernel/core/kmain.c
@@ -248,6 +248,12 @@ fs_t *setup_iofs(multiboot_info_t *mbd) {
 		ASSERT(nullfs_add_ram_file(iofs, name,
 					(char*)mods[i].mod_start,
 					len, FM_READ | FM_MMAP));
+
+		if (strncmp(modname, "kernel.map", 10) == 0) {
+			// remark: load_kernel_symbol_map modifies the data region,
+			// which is not a problem because nullfs_add_ram_file copied the thing already
+			load_kernel_symbol_map((char*)mods[i].mod_start, len);
+		}
 	}
 
 	return iofs;
diff --git a/src/kernel/core/kmalloc.c b/src/kernel/core/kmalloc.c
index cc20487..53ac83c 100644
--- a/src/kernel/core/kmalloc.c
+++ b/src/kernel/core/kmalloc.c
@@ -8,7 +8,7 @@
 #include <region.h>
 #include <freemem.h>
 
-static void* page_alloc_fun_for_kmalloc(size_t bytes) {
+void* page_alloc_fun_for_kmalloc(size_t bytes) {
 	void* addr = region_alloc(bytes, "Core kernel heap");
 	if (addr == 0) return 0;
 
@@ -59,7 +59,7 @@ void kmalloc_setup() {
 										region_free_unmap_free);
 }
 
-static void* malloc0(size_t sz) {
+void* malloc0(size_t sz) {
 	void* res = 0;
 
 	mutex_lock(&malloc_mutex);
diff --git a/src/kernel/core/paging.c b/src/kernel/core/paging.c
index cefb8c3..fa22879 100644
--- a/src/kernel/core/paging.c
+++ b/src/kernel/core/paging.c
@@ -68,7 +68,6 @@ void page_fault_handler(registers_t *regs) {
 		if ((size_t)vaddr < PAGE_SIZE) {
 			dbg_printf("Null pointer dereference in kernel code (0x%p)\n", vaddr);
 			dbg_dump_registers(regs);
-			dbg_print_region_info();
 			PANIC("Null pointer dereference in kernel code.");
 		} else if ((size_t)vaddr < K_HIGHHALF_ADDR) {
 			if (pd->user_pfh == 0) {
@@ -110,7 +109,6 @@ void page_fault_handler(registers_t *regs) {
 
 			dbg_printf("Kernel pagefault in region with no handler at 0x%p (%s region)\n", vaddr, region);
 			dbg_dump_registers(regs);
-			dbg_print_region_info();
 			PANIC("Unhandled kernel space page fault");
 		}
 	}
diff --git a/src/kernel/core/region.c b/src/kernel/core/region.c
index 1f1958f..c4c34d1 100644
--- a/src/kernel/core/region.c
+++ b/src/kernel/core/region.c
@@ -35,13 +35,13 @@ STATIC_MUTEX(ra_mutex);	// region allocator mutex
 // HELPER FUNCTIONS FOR THE MANIPULATION OF THE REGION LISTS //
 // ========================================================= //
 
-static void add_unused_descriptor(descriptor_t *d) {
+void add_unused_descriptor(descriptor_t *d) {
 	n_unused_descriptors++;
 	d->unused_descriptor.next = first_unused_descriptor;
 	first_unused_descriptor = d;
 }
 
-static descriptor_t *get_unused_descriptor() {
+descriptor_t *get_unused_descriptor() {
 	descriptor_t *r = first_unused_descriptor;
 	if (r != 0) {
 		first_unused_descriptor = r->unused_descriptor.next;
@@ -50,7 +50,7 @@ static descriptor_t *get_unused_descriptor() {
 	return r;
 }
 
-static void remove_free_region(descriptor_t *d) {
+void remove_free_region(descriptor_t *d) {
 	if (first_free_region_by_size == d) {
 		first_free_region_by_size = d->free.next_by_size;
 	} else {
@@ -73,7 +73,7 @@ static void remove_free_region(descriptor_t *d) {
 	}
 }
 
-static void add_free_region(descriptor_t *d) {
+void add_free_region(descriptor_t *d) {
 	/*dbg_printf("Add free region 0x%p - 0x%p\n", d->free.addr, d->free.size + d->free.addr);*/
 	// Find position of region in address-ordered list
 	// Possibly concatenate free region
@@ -155,7 +155,7 @@ static void add_free_region(descriptor_t *d) {
 	}
 }
 
-static descriptor_t *find_used_region(void* addr) {
+descriptor_t *find_used_region(void* addr) {
 	for (descriptor_t *i = first_used_region; i != 0; i = i->used.next_by_addr) {
 		if (addr >= i->used.i.addr && addr < i->used.i.addr + i->used.i.size) return i;
 		if (i->used.i.addr > addr) break;
@@ -163,7 +163,7 @@ static descriptor_t *find_used_region(void* addr) {
 	return 0;
 }
 
-static void add_used_region(descriptor_t *d) {
+void add_used_region(descriptor_t *d) {
 	descriptor_t *i = first_used_region;
 	ASSERT(i->used.i.addr < d->used.i.addr);	// first region by address is never free
 
@@ -180,7 +180,7 @@ static void add_used_region(descriptor_t *d) {
 	ASSERT(false);
 }
 
-static void remove_used_region(descriptor_t *d) {
+void remove_used_region(descriptor_t *d) {
 	if (first_used_region == d) {
 		first_used_region = d->used.next_by_addr;
 	} else {
@@ -220,7 +220,7 @@ void region_allocator_init(void* kernel_data_end) {
 	first_used_region = u0;
 }
 
-static void region_free_inner(void* addr) {
+void region_free_inner(void* addr) {
 	descriptor_t *d = find_used_region(addr);
 	if (d == 0) return;
 
@@ -237,7 +237,7 @@ void region_free(void* addr) {
 	mutex_unlock(&ra_mutex);
 }
 
-static void* region_alloc_inner(size_t size, char* type, bool use_reserve) {
+void* region_alloc_inner(size_t size, char* type, bool use_reserve) {
 	size = PAGE_ALIGN_UP(size);
 
 	for (descriptor_t *i = first_free_region_by_size; i != 0; i = i->free.first_bigger) {
diff --git a/src/kernel/core/sys.c b/src/kernel/core/sys.c
index 8be6c7f..554c95e 100644
--- a/src/kernel/core/sys.c
+++ b/src/kernel/core/sys.c
@@ -1,6 +1,9 @@
 #include <sys.h>
 #include <dbglog.h>
 #include <thread.h>
+#include <string.h>
+
+#include <btree.h>
 
 
 // Kernel panic and kernel assert failure
@@ -9,6 +12,15 @@ static void panic_do(const char* type, const char *msg, const char* file, int li
 	asm volatile("cli;");
 	dbg_printf("/\n| %s:\t%s\n", type, msg);
 	dbg_printf("| File: \t%s:%i\n", file, line);
+
+	dbg_printf("- trace\n");
+	dbg_printf("| current thread: 0x%p\n", current_thread);
+	uint32_t *ebp;
+	asm volatile("mov %%ebp, %0":"=r"(ebp));
+	kernel_stacktrace(ebp[0], ebp[1]);
+
+	dbg_print_region_info();
+
 	dbg_printf("| System halted -_-'\n");
 	dbg_printf("\\---------------------------------------------------------/");
 	BOCHS_BREAKPOINT;
@@ -26,4 +38,50 @@ void panic_assert(const char* assertion, const char* file, int line) {
 	panic_do("ASSERT FAILED", assertion, file, line);
 }
 
+//  ---- kernel symbol map
+
+btree_t *kernel_symbol_map = 0;
+
+void load_kernel_symbol_map(char* text, size_t len) {
+	kernel_symbol_map = create_btree(id_key_cmp_fun, 0);
+	ASSERT (kernel_symbol_map != 0);
+
+	dbg_printf("Loading kernel symbol map...\n");
+
+	char* it = text;
+	while (it < text + len) {
+		char* eol = it;
+		while (eol < text + len && *eol != 0 && *eol != '\n') eol++;
+		if (eol >= text + len) break;
+		*eol = 0;
+
+		if (it[16] == '0' && it[17] == 'x' && it[34] == ' ' && it[49] == ' ') {
+			uint32_t addr = 0;
+			for (unsigned i = 18; i < 34; i++) {
+				addr *= 16;
+				if (it[i] >= '0' && it[i] <= '9') addr += it[i] - '0';
+				if (it[i] >= 'a' && it[i] <= 'f') addr += it[i] - 'a' + 10;
+			}
+			btree_add(kernel_symbol_map, (void*)addr, it + 50);
+		}
+
+		it = eol + 1;
+	} 
+}
+
+void kernel_stacktrace(uint32_t ebp, uint32_t eip) {
+	int i = 0;
+	while (ebp >= K_HIGHHALF_ADDR && eip >= K_HIGHHALF_ADDR && i++ < 10) {
+		char* sym = 0;
+		if (kernel_symbol_map != 0) sym = btree_lower(kernel_symbol_map, (void*)eip);
+
+		dbg_printf("| 0x%p	EIP: 0x%p  %s\n", ebp, eip, sym);
+
+		uint32_t *d = (uint32_t*)ebp;
+		ebp = d[0];
+		eip = d[1];
+	}
+}
+
+
 /* vim: set ts=4 sw=4 tw=0 noet :*/
diff --git a/src/kernel/core/thread.c b/src/kernel/core/thread.c
index 19ad6c8..1009ec7 100644
--- a/src/kernel/core/thread.c
+++ b/src/kernel/core/thread.c
@@ -120,7 +120,7 @@ void run_scheduler() {
 	// At this point, interrupts are disabled
 	// This function is expected NEVER TO RETURN
 
-	thread_t *prev_thread = current_thread;
+	/*thread_t *prev_thread = current_thread;*/
 
 	if (current_thread != 0 && current_thread->state == T_STATE_RUNNING) {
 		current_thread->last_ran = get_kernel_time();
@@ -129,7 +129,7 @@ void run_scheduler() {
 	}
 	current_thread = dequeue_thread();
 
-	if (current_thread != prev_thread) dbg_printf("[0x%p]\n", current_thread);
+	/*if (current_thread != prev_thread) dbg_printf("[0x%p]\n", current_thread);*/
 
 	if (current_thread != 0) {
 		thread_t *ptr = current_thread;
@@ -146,7 +146,7 @@ void run_scheduler() {
 	}
 }
 
-static void run_thread(void (*entry)(void*), void* data) {
+void run_thread(void (*entry)(void*), void* data) {
 	ASSERT(current_thread->state == T_STATE_RUNNING);
 
 	dbg_printf("Begin thread 0x%p (in process %d)\n",
@@ -210,6 +210,10 @@ thread_t *new_thread(entry_t entry, void* data) {
 	t->next_in_proc = 0;
 	t->user_ex_handler = 0;
 
+	t->waiting_on = 0;
+	t->n_waiting_on = 0;
+	t->next_waiter = 0;
+
 	return t;
 }
 
@@ -285,11 +289,11 @@ bool wait_on_many(void** x, size_t n) {
 
 	//  ---- Set ourselves as the waiting thread for all the requested objets
 
-	dbg_printf("Wait on many:");
-	for (size_t i = 0; i < n; i++) {
-		dbg_printf(" 0x%p", x[i]);
-	}
-	dbg_printf("\n");
+	/*dbg_printf("Wait on many:");*/
+	/*for (size_t i = 0; i < n; i++) {*/
+		/*dbg_printf(" 0x%p", x[i]);*/
+	/*}*/
+	/*dbg_printf("\n");*/
 
 	current_thread->waiting_on = x;
 	current_thread->n_waiting_on = n;
@@ -310,8 +314,12 @@ bool wait_on_many(void** x, size_t n) {
 	if (waiters == current_thread) {
 		waiters = current_thread->next_waiter;
 	} else {
+		ASSERT(waiters != 0);
 		for (thread_t *w = waiters; w->next_waiter != 0; w = w->next_waiter) {
-			if (w->next_waiter == current_thread) w->next_waiter = current_thread->next_waiter;
+			if (w->next_waiter == current_thread) {
+				w->next_waiter = current_thread->next_waiter;
+				break;
+			}
 		}
 	}
 
@@ -368,12 +376,12 @@ bool resume_on(void* x) {
 
 	int st = enter_critical(CL_NOINT);
 
-	dbg_printf("Resume on 0x%p:", x);
+	/*dbg_printf("Resume on 0x%p:", x);*/
 
 	for (thread_t *t = waiters; t != 0; t = t->next_waiter) {
 		for (int i = 0; i < t->n_waiting_on; i++) {
 			if (t->waiting_on[i] == x) {
-				dbg_printf(" 0x%p", t);
+				/*dbg_printf(" 0x%p", t);*/
 
 				if (t->state == T_STATE_PAUSED) {
 					t->state = T_STATE_RUNNING;
@@ -386,6 +394,7 @@ bool resume_on(void* x) {
 			}
 		}
 	}
+	/*dbg_printf("\n");*/
 
 	exit_critical(st);