Implemented TODO about not loading symbols at boot.

This saves ~0.5s of boot time here, but I suspect it might be better for CD.
Enabled loadSymbols in kernel settings so the behavior should be the same as before this change.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@34666 a95241bf-73f2-0310-859d-f6bbb57e9c96

data/settings/kernel/drivers/kernel

@@ -42,7 +42,7 @@
 	# Activates a hack that allows single-stepping under qemu
 	# to work.
 
-#load_symbols true
+load_symbols true
 	# load kernel and kernel add-on symbols, default is off
 
 #apm true

src/system/boot/loader/elf.cpp

@@ -9,6 +9,7 @@
 #include <boot/arch.h>
 #include <boot/platform.h>
 #include <boot/stage2.h>
+#include <driver_settings.h>
 #include <elf32.h>
 #include <kernel.h>
 
@@ -24,6 +25,17 @@
 #endif
 
 
+static bool _loadElfSymbols = false;
+
+
+void
+elf_init() {
+	void *settings = load_driver_settings("kernel");
+	_loadElfSymbols = !get_driver_boolean_parameter(settings, "load_symbols",
+		false, false);
+}
+
+
 static status_t
 verify_elf_header(struct Elf32_Ehdr &header)
 {
@@ -370,8 +382,7 @@ elf_load_image(int fd, preloaded_image *image)
 	image->debug_symbols = NULL;
 	image->debug_string_table = NULL;
 
-	// ToDo: this should be enabled by kernel settings!
-	if (1)
+	if (_loadElfSymbols)
 		load_elf_symbol_table(fd, image);
 
 	free(programHeaders);

src/system/boot/loader/elf.h

@@ -10,6 +10,7 @@
 #include <boot/vfs.h>
 
 
+extern void elf_init();
 extern status_t elf_load_image(Directory *directory, const char *path);
 extern status_t elf_load_image(int fd, preloaded_image *image);
 

src/system/boot/loader/loader.cpp

@@ -60,6 +60,7 @@ load_kernel(stage2_args *args, Directory *volume)
 
 	dprintf("load kernel...\n");
 
+	elf_init();
 	status_t status = elf_load_image(fd, &gKernelArgs.kernel_image);
 
 	close(fd);