[PATCH] initcall failure reporting
Andrew Morton [Sat, 25 Mar 2006 11:07:15 +0000 (03:07 -0800)]
We presently ignore the return values from initcalls.  But that can carry
useful debugging information.  So print it out if it's non-zero.

It turns out the -ENODEV happens quite a lot, due to built-in drivers which
have no hardware to drive.  So suppress that unless initcall_debug was
specified.

Also make the warning message more friendly by printing the name of the
initcall function.

Also drop the KERN_DEBUG from the initcall_debug message.  If we specified
inticall_debug then we obviously want to see the messages.

Acked-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

init/main.c

index 2714e0e..a596cb8 100644 (file)
@@ -571,17 +571,23 @@ static void __init do_initcalls(void)
        int count = preempt_count();
 
        for (call = __initcall_start; call < __initcall_end; call++) {
-               char *msg;
+               char *msg = NULL;
+               char msgbuf[40];
+               int result;
 
                if (initcall_debug) {
-                       printk(KERN_DEBUG "Calling initcall 0x%p", *call);
-                       print_fn_descriptor_symbol(": %s()", (unsigned long) *call);
+                       printk("Calling initcall 0x%p", *call);
+                       print_fn_descriptor_symbol(": %s()",
+                                       (unsigned long) *call);
                        printk("\n");
                }
 
-               (*call)();
+               result = (*call)();
 
-               msg = NULL;
+               if (result && (result != -ENODEV || initcall_debug)) {
+                       sprintf(msgbuf, "error code %d", result);
+                       msg = msgbuf;
+               }
                if (preempt_count() != count) {
                        msg = "preemption imbalance";
                        preempt_count() = count;
@@ -591,8 +597,10 @@ static void __init do_initcalls(void)
                        local_irq_enable();
                }
                if (msg) {
-                       printk(KERN_WARNING "error in initcall at 0x%p: "
-                               "returned with %s\n", *call, msg);
+                       printk(KERN_WARNING "initcall at 0x%p", *call);
+                       print_fn_descriptor_symbol(": %s()",
+                                       (unsigned long) *call);
+                       printk(": returned with %s\n", msg);
                }
        }