From: Todd Poynor <toddpoy...@google.com>
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 <toddpoy...@google.com>
---
drivers/base/dd.c | 50 +++++++++++++++++++++--------------------------
1 file changed, 22 insertions(+), 28 deletions(-)
Changes from v1:
* unsigned long long -> s64
* use ktime_to_us() instead of ktime_to_ns with shift
* print probe return value
* drop code that stopped output on end of initcall processing
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
@@ -62,26 +61,6 @@ 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.
*/
@@ -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 @@ static int really_probe(struct device *dev, struct
device_driver *drv)
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)
--
2.18.0.rc1.244.gcf134e6275-goog
