• Paul E. McKenney's avatar
    PM / runtime: Add _rcuidle suffix to allow rpm_idle() use from idle · d7737ce9
    Paul E. McKenney authored
    This commit appends a few _rcuidle suffixes to fix the following
    RCU-used-from-idle bug:
    
    > ===============================
    > [ INFO: suspicious RCU usage. ]
    > 4.6.0-rc5-next-20160426+ #1116 Not tainted
    > -------------------------------
    > include/trace/events/rpm.h:95 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: [<c052cc2c>] __rpm_callback+0x58/0x60
    >
    > stack backtrace:
    > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1116
    > 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 [<c052d5d0>] (rpm_suspend+0x580/0x768)
    > [<c052d5d0>] (rpm_suspend) from [<c052ec58>] (__pm_runtime_suspend+0x64/0x84)
    > [<c052ec58>] (__pm_runtime_suspend) from [<c04bf25c>] (omap2_gpio_prepare_for_idle+0x5c/0x70)
    > [<c04bf25c>] (omap2_gpio_prepare_for_idle) from [<c0125568>] (omap_sram_idle+0x140/0x244)
    > [<c0125568>] (omap_sram_idle) from [<c01269dc>] (omap3_enter_idle_bm+0xfc/0x1ec)
    > [<c01269dc>] (omap3_enter_idle_bm) from [<c0601bdc>] (cpuidle_enter_state+0x80/0x3d4)
    > [<c0601bdc>] (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)
    
    In the immortal words of Steven Rostedt, "*Whack* *Whack* *Whack*!!!"
    Reported-by: default avatarTony Lindgren <tony@atomide.com>
    Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
    Tested-by: default avatarTony Lindgren <tony@atomide.com>
    Tested-by: default avatarGuenter Roeck <linux@roeck-us.net>
    WhACKED-by: default avatarSteven Rostedt <rostedt@goodmis.org>
    Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
    d7737ce9
runtime.c 41.7 KB