Commit 4e37958d authored by Steven Rostedt (VMware)'s avatar Steven Rostedt (VMware)
Browse files

init, tracing: Have printk come through the trace events for initcall_debug 



With trace events set before and after the initcall function calls, instead
of having a separate routine for printing out the initcalls when
initcall_debug is specified on the kernel command line, have the code
register a callback to the tracepoints where the initcall trace events are.

This removes the need for having a separate function to do the initcalls as
the tracepoint callbacks can handle the printk. It also includes other
initcalls that are not called by the do_one_initcall() which includes
console and security initcalls.

Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
parent 58eacfff

init/main.c

+35 −16
Original line number Original line Diff line number Diff line
@@ -494,6 +494,10 @@ void __init __weak thread_stack_cache_init(void) 




void __init __weak mem_encrypt_init(void) { }

void __init __weak mem_encrypt_init(void) { }





bool initcall_debug;

core_param(initcall_debug, initcall_debug, bool, 0644);

static void __init initcall_debug_enable(void);



/*

/*

 * Set up kernel memory allocators

 * Set up kernel memory allocators

 */

 */
@@ -615,6 +619,9 @@ asmlinkage __visible void __init start_kernel(void) 
	/* Trace events are available after this */

	/* Trace events are available after this */

	trace_init();

	trace_init();





	if (initcall_debug)

		initcall_debug_enable();



	context_tracking_init();

	context_tracking_init();

	/* init some links before init_ISA_irqs() */

	/* init some links before init_ISA_irqs() */

	early_irq_init();

	early_irq_init();
@@ -731,9 +738,6 @@ static void __init do_ctors(void) 
#endif

#endif

}

}





bool initcall_debug;

core_param(initcall_debug, initcall_debug, bool, 0644);



#ifdef CONFIG_KALLSYMS

#ifdef CONFIG_KALLSYMS

struct blacklist_entry {

struct blacklist_entry {

	struct list_head next;

	struct list_head next;
@@ -803,37 +807,52 @@ static bool __init_or_module initcall_blacklisted(initcall_t fn) 
#endif

#endif

__setup("initcall_blacklist=", initcall_blacklist);

__setup("initcall_blacklist=", initcall_blacklist);





static int __init_or_module do_one_initcall_debug(initcall_t fn)

static __init_or_module void

trace_initcall_start_cb(void *data, initcall_t fn)

{

{

	ktime_t calltime, delta, rettime;

	ktime_t *calltime = (ktime_t *)data;

	unsigned long long duration;

	int ret;





	printk(KERN_DEBUG "calling  %pF @ %i\n", fn, task_pid_nr(current));

	printk(KERN_DEBUG "calling  %pF @ %i\n", fn, task_pid_nr(current));

	calltime = ktime_get();

	*calltime = ktime_get();

	ret = fn();

}



static __init_or_module void

trace_initcall_finish_cb(void *data, initcall_t fn, int ret)

{

	ktime_t *calltime = (ktime_t *)data;

	ktime_t delta, rettime;

	unsigned long long duration;



	rettime = ktime_get();

	rettime = ktime_get();

	delta = ktime_sub(rettime, calltime);

	delta = ktime_sub(rettime, *calltime);

	duration = (unsigned long long) ktime_to_ns(delta) >> 10;

	duration = (unsigned long long) ktime_to_ns(delta) >> 10;

	printk(KERN_DEBUG "initcall %pF returned %d after %lld usecs\n",

	printk(KERN_DEBUG "initcall %pF returned %d after %lld usecs\n",

		 fn, ret, duration);

		 fn, ret, duration);

}





	return ret;

static ktime_t initcall_calltime;



static void __init initcall_debug_enable(void)

{

	int ret;



	ret = register_trace_initcall_start(trace_initcall_start_cb,

					    &initcall_calltime);

	ret |= register_trace_initcall_finish(trace_initcall_finish_cb,

					      &initcall_calltime);

	WARN(ret, "Failed to register initcall tracepoints\n");

}

}





int __init_or_module do_one_initcall(initcall_t fn)

int __init_or_module do_one_initcall(initcall_t fn)

{

{

	int count = preempt_count();

	int count = preempt_count();

	int ret;

	char msgbuf[64];

	char msgbuf[64];

	int ret;





	if (initcall_blacklisted(fn))

	if (initcall_blacklisted(fn))

		return -EPERM;

		return -EPERM;





	trace_initcall_start(fn);

	trace_initcall_start(fn);

	if (initcall_debug)

		ret = do_one_initcall_debug(fn);

	else

	ret = fn();

	ret = fn();

	trace_initcall_finish(fn, ret);

	trace_initcall_finish(fn, ret);

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