Re: [PATCH arm 1/1] arm: Use _rcuidle tracepoint to allow use from idle

From: Tony Lindgren
Date: Tue Apr 26 2016 - 14:29:48 EST


* Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> [160426 10:53]:
> Does the following patch help?

It just changes the output.. See below.

> It is quite possible that there are quite a few more of these. If this
> is the case, then one way to make the kernel list more of them on a
> given boot is to build with CONFIG_PROVE_RCU_REPEATEDLY=y.

OK

Regards,

Tony

8< ------------------
CPU: Testing write buffer coherency: ok
CPU0: thread -1, cpu 0, socket 0, mpidr 80000000


RCU used illegally from idle CPU!
rcu_scheduler_active = 1, debug_locks = 0
RCU used illegally from extended quiescent state!
no locks held by swapper/1/0.

stack backtrace:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.6.0-rc5-next-20160426+ #1113
Hardware name: Generic OMAP4 (Flattened Device Tree)
[<c0110290>] (unwind_backtrace) from [<c010c3a8>] (show_stack+0x10/0x14)
[<c010c3a8>] (show_stack) from [<c047ff88>] (dump_stack+0xb0/0xe4)
[<c047ff88>] (dump_stack) from [<c012c014>] (pwrdm_set_next_pwrst+0x100/0x1d4)
[<c012c014>] (pwrdm_set_next_pwrst) from [<c0126120>] (omap4_enter_lowpower+0xc8/0x230)
[<c0126120>] (omap4_enter_lowpower) from [<c0126c24>] (omap_enter_idle_coupled+0x6c/0x254)
[<c0126c24>] (omap_enter_idle_coupled) from [<c0601dfc>] (cpuidle_enter_state+0x80/0x3d4)
[<c0601dfc>] (cpuidle_enter_state) from [<c0603d30>] (cpuidle_enter_state_coupled+0x348/0x390)
[<c0603d30>] (cpuidle_enter_state_coupled) from [<c0183d34>] (cpu_startup_entry+0x198/0x3a0)
[<c0183d34>] (cpu_startup_entry) from [<8010162c>] (0x8010162c)
hw-breakpoint: Failed to enable monitor mode on CPU 0.