From: "Liu, Xinwu" <[email protected]> The schedule policy of thread "kidle_inject" is SCHED_NORMAL: [ 772.796284] intel_powerclamp: Start idle injection to reduce power [ 772.825757] ------------[ cut here ]------------ [ 772.825877] WARNING: CPU: 0 PID: 2140 at ../../../../../../kernel/glv/kernel/sched/idle.c:298 play_idle+0x16f/0x230 [ 772.826096] Modules linked in: ip6table_raw iptable_raw hci_uart bluetooth rfkill_gpio cfg80211 imc_ipc(O) [ 772.826194] CPU: 0 PID: 2140 Comm: kidle_inject/0 Tainted: G IO 4.9.0-ge701680f3a17 #1 [ 772.826373] ffffc90001103d58 ffffffff813ba085 0000000000000000 0000000000000000 [ 772.826552] ffffc90001103d98 ffffffff810953e1 0000012a691441c0 0000000000000006 [ 772.826731] 0000000000000002 ffff88006a39d708 ffff8800691441c0 ffffe8ffffc0dab8 [ 772.826794] Call Trace: [ 772.826903] [<ffffffff813ba085>] dump_stack+0x67/0x92 [ 772.827007] [<ffffffff810953e1>] __warn+0xd1/0xf0 [ 772.827124] [<ffffffff810954cd>] warn_slowpath_null+0x1d/0x20 [ 772.827234] [<ffffffff810d6c6f>] play_idle+0x16f/0x230 [ 772.827365] [<ffffffff81a9b4b7>] ? __schedule+0x217/0x6f0 [ 772.827485] [<ffffffff81856c9a>] clamp_idle_injection_func+0x6a/0x1f0 [ 772.827612] [<ffffffff810b568d>] kthread_worker_fn+0xdd/0x200 [ 772.827741] [<ffffffff810b55b0>] ? __kthread_init_worker+0x50/0x50 [ 772.827860] [<ffffffff810b5542>] kthread+0x102/0x120 [ 772.828004] [<ffffffff810b5440>] ? kthread_park+0x60/0x60 [ 772.828118] [<ffffffff81aa2517>] ret_from_fork+0x27/0x40 [ 772.828228] ---[ end trace bb738d5d79381554 ]---
Normaly, the user thread have not the capability "CAP_SYS_NICE" (and they shouldn't), it will fail to change the schedule policy. So, fix it by changing by themselves. Signed-off-by: Liu, Xinwu <[email protected]> Signed-off-by: Zhang, Di <[email protected]> --- drivers/thermal/intel_powerclamp.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/thermal/intel_powerclamp.c b/drivers/thermal/intel_powerclamp.c index 83e6971..3a2e5fe 100644 --- a/drivers/thermal/intel_powerclamp.c +++ b/drivers/thermal/intel_powerclamp.c @@ -50,6 +50,7 @@ #include <linux/debugfs.h> #include <linux/seq_file.h> #include <linux/sched/rt.h> +#include <linux/once.h> #include <asm/nmi.h> #include <asm/msr.h> @@ -385,6 +386,7 @@ static void clamp_balancing_func(struct kthread_work *work) unsigned int compensated_ratio; int interval; /* jiffies to sleep for each attempt */ + DO_ONCE(sched_setscheduler, current, SCHED_FIFO, &sparam); w_data = container_of(work, struct powerclamp_worker_data, balancing_work); @@ -507,7 +509,6 @@ static void start_power_clamp_worker(unsigned long cpu) w_data->cpu = cpu; w_data->clamping = true; set_bit(cpu, cpu_clamping_mask); - sched_setscheduler(worker->task, SCHED_FIFO, &sparam); kthread_init_work(&w_data->balancing_work, clamp_balancing_func); kthread_init_delayed_work(&w_data->idle_injection_work, clamp_idle_injection_func); -- 1.9.1
