enhance initcall_debug, measure latency

enhance the initcall_debug boot option: - measure the time the initcall took to execute and report it in units of milliseconds. - show the return code of initcalls (useful to see failures and to make sure that an initcall hung) [[email protected]: fix printk warning] Signed-off-by: Ingo Molnar <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
maraz · May 8, 2007 · 8f0c45c · 8f0c45c
1 parent b73a7e7
commit 8f0c45c
Showing 1 changed file with 17 additions and 0 deletions.
diff --git a/init/main.c b/init/main.c
@@ -648,6 +648,7 @@ static void __init do_initcalls(void)
 	int count = preempt_count();
 
 	for (call = __initcall_start; call < __initcall_end; call++) {
+		ktime_t t0, t1, delta;
 		char *msg = NULL;
 		char msgbuf[40];
 		int result;
@@ -657,10 +658,26 @@ static void __init do_initcalls(void)
 			print_fn_descriptor_symbol(": %s()",
 					(unsigned long) *call);
 			printk("\n");
+			t0 = ktime_get();
 		}
 
 		result = (*call)();
 
+		if (initcall_debug) {
+			t1 = ktime_get();
+			delta = ktime_sub(t1, t0);
+
+			printk("initcall 0x%p", *call);
+			print_fn_descriptor_symbol(": %s()",
+					(unsigned long) *call);
+			printk(" returned %d.\n", result);
+
+			printk("initcall 0x%p ran for %Ld msecs: ",
+				*call, (unsigned long long)delta.tv64 >> 20);
+			print_fn_descriptor_symbol("%s()\n",
+				(unsigned long) *call);
+		}
+
 		if (result && result != -ENODEV && initcall_debug) {
 			sprintf(msgbuf, "error code %d", result);
 			msg = msgbuf;