| Message ID | 1353548752.3425.3.camel@ThinkPad-T5421.cn.ibm.com (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
On 11/22/2012 2:45 AM, Li Zhong wrote: > Adding linux-pm list, and ACKs. > > I saw this suspicious RCU usage on the next tree of 11/15 > > [ 67.123404] =============================== > [ 67.123413] [ INFO: suspicious RCU usage. ] > [ 67.123423] 3.7.0-rc5-next-20121115-dirty #1 Not tainted > [ 67.123434] ------------------------------- > [ 67.123444] include/trace/events/timer.h:186 suspicious rcu_dereference_check() usage! > [ 67.123458] > [ 67.123458] other info that might help us debug this: > [ 67.123458] > [ 67.123474] > [ 67.123474] RCU used illegally from idle CPU! > [ 67.123474] rcu_scheduler_active = 1, debug_locks = 0 > [ 67.123493] RCU used illegally from extended quiescent state! > [ 67.123507] 1 lock held by swapper/1/0: > [ 67.123516] #0: (&cpu_base->lock){-.-...}, at: [<c0000000000979b0>] .__hrtimer_start_range_ns+0x28c/0x524 > [ 67.123555] > [ 67.123555] stack backtrace: > [ 67.123566] Call Trace: > [ 67.123576] [c0000001e2ccb920] [c00000000001275c] .show_stack+0x78/0x184 (unreliable) > [ 67.123599] [c0000001e2ccb9d0] [c0000000000c15a0] .lockdep_rcu_suspicious+0x120/0x148 > [ 67.123619] [c0000001e2ccba70] [c00000000009601c] .enqueue_hrtimer+0x1c0/0x1c8 > [ 67.123639] [c0000001e2ccbb00] [c000000000097aa0] .__hrtimer_start_range_ns+0x37c/0x524 > [ 67.123660] [c0000001e2ccbc20] [c0000000005c9698] .menu_select+0x508/0x5bc > [ 67.123678] [c0000001e2ccbd20] [c0000000005c740c] .cpuidle_idle_call+0xa8/0x6e4 > [ 67.123699] [c0000001e2ccbdd0] [c0000000000459a0] .pSeries_idle+0x10/0x34 > [ 67.123717] [c0000001e2ccbe40] [c000000000014dc8] .cpu_idle+0x130/0x280 > [ 67.123738] [c0000001e2ccbee0] [c0000000006ffa8c] .start_secondary+0x378/0x384 > [ 67.123758] [c0000001e2ccbf90] [c00000000000936c] .start_secondary_prolog+0x10/0x14 > > hrtimer_start was added in 198fd638 and ae515197. The patch below tries > to use RCU_NONIDLE around it to avoid the above report. Applied to the linux-next branch of the linux-pm.git tree as v3.8 material. Thanks, Rafael > Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> > Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> > Reviewed-by: Rik van Riel <riel@redhat.com> > --- > drivers/cpuidle/governors/menu.c | 10 ++++++---- > 1 files changed, 6 insertions(+), 4 deletions(-) > > diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c > index 2efee27..bd40b94 100644 > --- a/drivers/cpuidle/governors/menu.c > +++ b/drivers/cpuidle/governors/menu.c > @@ -407,8 +407,9 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) > perfect_us = perfect_cstate_ms * 1000; > > if (repeat && (4 * timer_us < data->expected_us)) { > - hrtimer_start(hrtmr, ns_to_ktime(1000 * timer_us), > - HRTIMER_MODE_REL_PINNED); > + RCU_NONIDLE(hrtimer_start(hrtmr, > + ns_to_ktime(1000 * timer_us), > + HRTIMER_MODE_REL_PINNED)); > /* In repeat case, menu hrtimer is started */ > per_cpu(hrtimer_status, cpu) = MENU_HRTIMER_REPEAT; > } else if (perfect_us < data->expected_us) { > @@ -418,8 +419,9 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) > * In that case, it makes sense to re-enter > * into a deeper C-state after some time. > */ > - hrtimer_start(hrtmr, ns_to_ktime(1000 * timer_us), > - HRTIMER_MODE_REL_PINNED); > + RCU_NONIDLE(hrtimer_start(hrtmr, > + ns_to_ktime(1000 * timer_us), > + HRTIMER_MODE_REL_PINNED)); > /* In general case, menu hrtimer is started */ > per_cpu(hrtimer_status, cpu) = MENU_HRTIMER_GENERAL; > } --------------------------------------------------------------------- Intel Technology Poland sp. z o.o. z siedziba w Gdansku ul. Slowackiego 173 80-298 Gdansk Sad Rejonowy Gdansk Polnoc w Gdansku, VII Wydzial Gospodarczy Krajowego Rejestru Sadowego, numer KRS 101882 NIP 957-07-52-316 Kapital zakladowy 200.000 zl This e-mail and any attachments may contain confidential material for the sole use of the intended recipient(s). Any review or distribution by others is strictly prohibited. If you are not the intended recipient, please contact the sender and delete all copies.
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c index 2efee27..bd40b94 100644 --- a/drivers/cpuidle/governors/menu.c +++ b/drivers/cpuidle/governors/menu.c @@ -407,8 +407,9 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) perfect_us = perfect_cstate_ms * 1000; if (repeat && (4 * timer_us < data->expected_us)) { - hrtimer_start(hrtmr, ns_to_ktime(1000 * timer_us), - HRTIMER_MODE_REL_PINNED); + RCU_NONIDLE(hrtimer_start(hrtmr, + ns_to_ktime(1000 * timer_us), + HRTIMER_MODE_REL_PINNED)); /* In repeat case, menu hrtimer is started */ per_cpu(hrtimer_status, cpu) = MENU_HRTIMER_REPEAT; } else if (perfect_us < data->expected_us) { @@ -418,8 +419,9 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) * In that case, it makes sense to re-enter * into a deeper C-state after some time. */ - hrtimer_start(hrtmr, ns_to_ktime(1000 * timer_us), - HRTIMER_MODE_REL_PINNED); + RCU_NONIDLE(hrtimer_start(hrtmr, + ns_to_ktime(1000 * timer_us), + HRTIMER_MODE_REL_PINNED)); /* In general case, menu hrtimer is started */ per_cpu(hrtimer_status, cpu) = MENU_HRTIMER_GENERAL; }
Adding linux-pm list, and ACKs. I saw this suspicious RCU usage on the next tree of 11/15 [ 67.123404] =============================== [ 67.123413] [ INFO: suspicious RCU usage. ] [ 67.123423] 3.7.0-rc5-next-20121115-dirty #1 Not tainted [ 67.123434] ------------------------------- [ 67.123444] include/trace/events/timer.h:186 suspicious rcu_dereference_check() usage! [ 67.123458] [ 67.123458] other info that might help us debug this: [ 67.123458] [ 67.123474] [ 67.123474] RCU used illegally from idle CPU! [ 67.123474] rcu_scheduler_active = 1, debug_locks = 0 [ 67.123493] RCU used illegally from extended quiescent state! [ 67.123507] 1 lock held by swapper/1/0: [ 67.123516] #0: (&cpu_base->lock){-.-...}, at: [<c0000000000979b0>] .__hrtimer_start_range_ns+0x28c/0x524 [ 67.123555] [ 67.123555] stack backtrace: [ 67.123566] Call Trace: [ 67.123576] [c0000001e2ccb920] [c00000000001275c] .show_stack+0x78/0x184 (unreliable) [ 67.123599] [c0000001e2ccb9d0] [c0000000000c15a0] .lockdep_rcu_suspicious+0x120/0x148 [ 67.123619] [c0000001e2ccba70] [c00000000009601c] .enqueue_hrtimer+0x1c0/0x1c8 [ 67.123639] [c0000001e2ccbb00] [c000000000097aa0] .__hrtimer_start_range_ns+0x37c/0x524 [ 67.123660] [c0000001e2ccbc20] [c0000000005c9698] .menu_select+0x508/0x5bc [ 67.123678] [c0000001e2ccbd20] [c0000000005c740c] .cpuidle_idle_call+0xa8/0x6e4 [ 67.123699] [c0000001e2ccbdd0] [c0000000000459a0] .pSeries_idle+0x10/0x34 [ 67.123717] [c0000001e2ccbe40] [c000000000014dc8] .cpu_idle+0x130/0x280 [ 67.123738] [c0000001e2ccbee0] [c0000000006ffa8c] .start_secondary+0x378/0x384 [ 67.123758] [c0000001e2ccbf90] [c00000000000936c] .start_secondary_prolog+0x10/0x14 hrtimer_start was added in 198fd638 and ae515197. The patch below tries to use RCU_NONIDLE around it to avoid the above report. Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Rik van Riel <riel@redhat.com> --- drivers/cpuidle/governors/menu.c | 10 ++++++---- 1 files changed, 6 insertions(+), 4 deletions(-)