From mboxrd@z Thu Jan 1 00:00:00 1970 From: paulmck@linux.vnet.ibm.com (Paul E. McKenney) Date: Tue, 26 Apr 2016 13:06:32 -0700 Subject: [PATCH arm 1/1] arm: Use _rcuidle tracepoint to allow use from idle In-Reply-To: <20160426155229.47b4a9f6@gandalf.local.home> References: <1461617335-22372-1-git-send-email-paulmck@linux.vnet.ibm.com> <20160426150031.GP5995@atomide.com> <20160426175214.GJ3715@linux.vnet.ibm.com> <20160426182939.GO5995@atomide.com> <20160426190755.GK3715@linux.vnet.ibm.com> <20160426193949.GP5995@atomide.com> <20160426154414.7bb33de4@gandalf.local.home> <20160426195121.GN3715@linux.vnet.ibm.com> <20160426155229.47b4a9f6@gandalf.local.home> Message-ID: <20160426200632.GP3715@linux.vnet.ibm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, Apr 26, 2016 at 03:52:29PM -0400, Steven Rostedt wrote: > On Tue, 26 Apr 2016 12:51:21 -0700 > "Paul E. McKenney" wrote: > > > On Tue, Apr 26, 2016 at 03:44:14PM -0400, Steven Rostedt wrote: > > > On Tue, 26 Apr 2016 12:39:50 -0700 > > > Tony Lindgren wrote: > > > > > > > > > > With these omap4 is now OK. But omap3 produces yet another warning, > > > > See below :) > > > > > > > > Regards, > > > > > > > > Tony > > > > > > > > 8< ------------------ > > > > =============================== > > > > [ INFO: suspicious RCU usage. ] > > > > 4.6.0-rc5-next-20160426+ #1114 Not tainted > > > > ------------------------------- > > > > include/trace/events/clk.h:59 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! > > > > 2 locks held by swapper/0/0: > > > > #0: (&oh->hwmod_key#30){......}, at: [] omap_hwmod_idle+0x18/0x44 > > > > #1: (enable_lock){......}, at: [] clk_enable_lock+0x18/0x124 > > > > > > > > stack backtrace: > > > > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1114 > > > > Hardware name: Generic OMAP36xx (Flattened Device Tree) > > > > [] (unwind_backtrace) from [] (show_stack+0x10/0x14) > > > > [] (show_stack) from [] (dump_stack+0xb0/0xe4) > > > > [] (dump_stack) from [] (clk_core_disable+0x17c/0x348) > > > > [] (clk_core_disable) from [] (clk_disable+0x24/0x30) > > > > [] (clk_disable) from [] (_disable_clocks+0x18/0x7c) > > > > [] (_disable_clocks) from [] (_idle+0x12c/0x230) > > > > [] (_idle) from [] (omap_hwmod_idle+0x24/0x44) > > > > [] (omap_hwmod_idle) from [] (omap_device_idle+0x3c/0x90) > > > > [] (omap_device_idle) from [] (__rpm_callback+0x2c/0x60) > > > > [] (__rpm_callback) from [] (rpm_callback+0x20/0x80) > > > > [] (rpm_callback) from [] (rpm_suspend+0x100/0x768) > > > > [] (rpm_suspend) from [] (__pm_runtime_suspend+0x64/0x84) > > > > [] (__pm_runtime_suspend) from [] (omap2_gpio_prepare_for_idle+0x5 > > > > c/0x70) > > > > [] (omap2_gpio_prepare_for_idle) from [] (omap_sram_idle+0x140/0x2 > > > > 44) > > > > [] (omap_sram_idle) from [] (omap3_enter_idle_bm+0xfc/0x1ec) > > > > [] (omap3_enter_idle_bm) from [] (cpuidle_enter_state+0x80/0x3d4) > > > > [] (cpuidle_enter_state) from [] (cpu_startup_entry+0x198/0x3a0) > > > > [] (cpu_startup_entry) from [] (start_kernel+0x354/0x3c8) > > > > [] (start_kernel) from [<8000807c>] (0x8000807c) > > > > > > *Whack* *Whack* *Whack*!!! > > > > > > Signed-off-by: Steven Rostedt > > > > Or use Steven's identical patch, your choice. ;-) > > I don't care which you use. But if you use mine, you must keep the > *Whack* *Whack* *Whack*!!! in the change log. I included it in the last one. ;-) Thanx, Paul