From: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Date: Tue, 26 Apr 2016 20:38:55 +0000 (-0700)
Subject: PM / runtime: Add _rcuidle suffix to allow rpm_resume() to be called from idle
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=d44c950e9398e639e124014e5872480a37b67259;p=linux-beck.git

PM / runtime: Add _rcuidle suffix to allow rpm_resume() to be called from idle

This commit applies another _rcuidle suffix to fix an RCU use from
idle.

> ===============================
> [ INFO: suspicious RCU usage. ]
> 4.6.0-rc5-next-20160426+ #1122 Not tainted
> -------------------------------
> include/trace/events/rpm.h:69 suspicious rcu_dereference_check() usage!
>
> other info that might help us debug this:
>
>
> RCU used illegally from idle CPU!
> rcu_scheduler_active = 1, debug_locks = 0
> RCU used illegally from extended quiescent state!
> 1 lock held by swapper/0/0:
>  #0:  (&(&dev->power.lock)->rlock){-.-...}, at: [<c052e3dc>] __pm_runtime_resume+0x3c/0x64
>
> stack backtrace:
> CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1122
> Hardware name: Generic OMAP36xx (Flattened Device Tree)
> [<c0110290>] (unwind_backtrace) from [<c010c3a8>] (show_stack+0x10/0x14)
> [<c010c3a8>] (show_stack) from [<c047fd68>] (dump_stack+0xb0/0xe4)
> [<c047fd68>] (dump_stack) from [<c052e178>] (rpm_resume+0x5cc/0x7f4)
> [<c052e178>] (rpm_resume) from [<c052e3ec>] (__pm_runtime_resume+0x4c/0x64)
> [<c052e3ec>] (__pm_runtime_resume) from [<c04bf2c4>] (omap2_gpio_resume_after_idle+0x54/0x68)
> [<c04bf2c4>] (omap2_gpio_resume_after_idle) from [<c01269dc>] (omap3_enter_idle_bm+0xfc/0x1ec)
> [<c01269dc>] (omap3_enter_idle_bm) from [<c060198c>] (cpuidle_enter_state+0x80/0x3d4)
> [<c060198c>] (cpuidle_enter_state) from [<c0183b08>] (cpu_startup_entry+0x198/0x3a0)
> [<c0183b08>] (cpu_startup_entry) from [<c0b00c0c>] (start_kernel+0x354/0x3c8)
> [<c0b00c0c>] (start_kernel) from [<8000807c>] (0x8000807c)

Reported-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---

diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index e097d355cc04..76127e109ed2 100644
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -601,7 +601,7 @@ static int rpm_resume(struct device *dev, int rpmflags)
 	struct device *parent = NULL;
 	int retval = 0;
 
-	trace_rpm_resume(dev, rpmflags);
+	trace_rpm_resume_rcuidle(dev, rpmflags);
 
  repeat:
 	if (dev->power.runtime_error)
@@ -764,7 +764,7 @@ static int rpm_resume(struct device *dev, int rpmflags)
 		spin_lock_irq(&dev->power.lock);
 	}
 
-	trace_rpm_return_int(dev, _THIS_IP_, retval);
+	trace_rpm_return_int_rcuidle(dev, _THIS_IP_, retval);
 
 	return retval;
 }