From: Ingo Molnar 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) Signed-off-by: Ingo Molnar Signed-off-by: Andrew Morton --- init/main.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff -puN init/main.c~enhance-initcall_debug-measure-latency init/main.c --- a/init/main.c~enhance-initcall_debug-measure-latency +++ a/init/main.c @@ -652,6 +652,7 @@ 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; @@ -661,10 +662,26 @@ 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, 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; _