drivers: base: initcall_debug logs for driver probe times

Add initcall_debug logs for each driver device probe call, for example:

   probe of a3800000.ramoops returned 1 after 3007 usecs

This replaces the previous code added to report times for deferred
probes.  It also reports OF platform bus device creates that were
formerly lumped together in a single entry for function
of_platform_default_populate_init, as well as helping to annotate other
initcalls that involve device probing.

Remove restriction on printing probe times only during initcalls, since
initcall_debug now continues to show driver timing info past the boot
phase.

Signed-off-by: Todd Poynor <toddpoynor@google.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 22 insertions, 28 deletions

diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index 1435d7281c66..6ea9c5cece71 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -53,7 +53,6 @@ static DEFINE_MUTEX(deferred_probe_mutex);
 static LIST_HEAD(deferred_probe_pending_list);
 static LIST_HEAD(deferred_probe_active_list);
 static atomic_t deferred_trigger_count = ATOMIC_INIT(0);
-static bool initcalls_done;
 
 /*
  * In some cases, like suspend to RAM or hibernation, It might be reasonable
@@ -63,26 +62,6 @@ static bool initcalls_done;
 static bool defer_all_probes;
 
 /*
- * For initcall_debug, show the deferred probes executed in late_initcall
- * processing.
- */
-static void deferred_probe_debug(struct device *dev)
-{
-        ktime_t calltime, delta, rettime;
-        unsigned long long duration;
-
-        printk(KERN_DEBUG "deferred probe %s @ %i\n", dev_name(dev),
-               task_pid_nr(current));
-        calltime = ktime_get();
-        bus_probe_device(dev);
-        rettime = ktime_get();
-        delta = ktime_sub(rettime, calltime);
-        duration = (unsigned long long) ktime_to_ns(delta) >> 10;
-        printk(KERN_DEBUG "deferred probe %s returned after %lld usecs\n",
-               dev_name(dev), duration);
-}
-
-/*
  * deferred_probe_work_func() - Retry probing devices in the active list.
  */
 static void deferred_probe_work_func(struct work_struct *work)
@@ -125,11 +104,7 @@ static void deferred_probe_work_func(struct work_struct *work)
                 device_pm_move_to_tail(dev);
 
                 dev_dbg(dev, "Retrying from deferred list\n");
-                if (initcall_debug && !initcalls_done)
-                        deferred_probe_debug(dev);
-                else
-                        bus_probe_device(dev);
-
+                bus_probe_device(dev);
                 mutex_lock(&deferred_probe_mutex);
 
                 put_device(dev);
@@ -237,7 +212,6 @@ static int deferred_probe_initcall(void)
         driver_deferred_probe_trigger();
         /* Sort as many dependencies as possible before exiting initcalls */
         flush_work(&deferred_probe_work);
-        initcalls_done = true;
         return 0;
 }
 late_initcall(deferred_probe_initcall);
@@ -527,6 +501,23 @@ done:
         return ret;
 }
 
+/*
+ * For initcall_debug, show the driver probe time.
+ */
+static int really_probe_debug(struct device *dev, struct device_driver *drv)
+{
+        ktime_t calltime, delta, rettime;
+        int ret;
+
+        calltime = ktime_get();
+        ret = really_probe(dev, drv);
+        rettime = ktime_get();
+        delta = ktime_sub(rettime, calltime);
+        printk(KERN_DEBUG "probe of %s returned %d after %lld usecs\n",
+               dev_name(dev), ret, (s64) ktime_to_us(delta));
+        return ret;
+}
+
 /**
  * driver_probe_done
  * Determine if the probe sequence is finished or not.
@@ -585,7 +576,10 @@ int driver_probe_device(struct device_driver *drv, struct device *dev)
                 pm_runtime_get_sync(dev->parent);
 
         pm_runtime_barrier(dev);
-        ret = really_probe(dev, drv);
+        if (initcall_debug)
+                ret = really_probe_debug(dev, drv);
+        else
+                ret = really_probe(dev, drv);
         pm_request_idle(dev);
 
         if (dev->parent)