: (16GPs behind) idle=4cc/0/0x0softirq=1782/1782fqs=1[61.290408] rcu: (detectedby2, t=5282jiffies, g=633, q=71) [61.290424] Sending NMIfromCPU2to CPUs4: [61.290471] NMI backtraceforcpu4skipped: idling at native_safe_halt+0xe/0x10[61.291424] rcu: rcu_sched kthread starvedfor5244...
rcu_sched kthread starved for 23807 jiffies! g7075 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1 ->cpu=5 Unless rcu_sched kthread gets sufficient CPU time, OOM is now expected behavior. 使CPU 时间的宽限期 kthread 饿死当然会导致 RCU CPU 停顿警告,即使所有 CPU 和任务都已通过所需的静止状态。
kthread starved for 23807 jiffies! g7075 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1 ->cpu=5 即使所有CPU和任务均已通过所需的静态状态,使CPU时间的宽限期kthreads Starving, 当然也会导致RCU CPU停顿警告。"g"数字显示当前的宽限期序列号,"f"在宽限期kthread的-> gp_flags命令之前,"RCU_GP_WAIT_FQ...
[17:41:22] [ 67.371720] Sending NMI from CPU 0 to CPUs 1: [17:41:32] [ 77.375403] rcu_sched kthread starved for 2034 jiffies! g911 c910 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=0 [17:41:32] [ 77.385787] rcu_sched R running task 0 9 2 0x00000000 [17:41:32] [ 7...
g20409 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200 [ 94.691925] rcu: Possible timer handling issue on cpu=0 timer-softirq=1664 [ 94.691929] rcu: rcu_sched kthread starved for 59998 jiffies! g20409 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200 ->cpu=0 [ 94.691936] rcu: Unless rcu_sched...
kmsg中此时还会打印“rcu_.*kthread starved for”关键字,以及一些额外的debug信息(详细信息后面会有示例)。 (8)在开了CONFIG_PREEMPT的内核中,一个绑核的rt线程可能抢占一个低优先级线程,该低优先级线程如果在rcu read-side临界区时,会导致rcu stall。在该低优先级线程不允许调度到其他cpu时,伤害尤为明显,因为...
static void rcu_check_gp_kthread_starvation(void) { struct task_struct *gpk = rcu_state.gp_kthread; unsigned long j; if (rcu_is_gp_kthread_starving(&j)) { pr_err("%s kthread starved for %ld jiffies! g%ld f%#x %s(%d) ->state=%#lx ->cpu=%d\n", ...
INFO: rcu_sched self-detected stall on CPUINFO: rcu_sched self-detected stall on CPU 0: (5250 ticks this GP) idle=e15/140000000000001/0 softirq=0/0 fqs=24 (t=5250 jiffies g=3340 c=3339 q=11378)rcu_sched kthread starved for 5226 jiffies!Task dump for CPU 0:run R...
INFO: rcu_sched self-detected stall on CPU [ 1739.452511] rcu: 7-...: (59616 ticks this GP) idle=d4ec/1/0x4000000000000000 softirq=18636/18636 fqs=5263 [ 1739.453498] rcu: (t=60008 jiffies g=67965 q=36939 ncpus=8) [ 1739.454053] rcu: rcu_sched kthread starved for 47871 jiffies...
[285165.790740] INFO: rcu_sched self-detected stall on CPU[285165.795988] 0-...: (1 GPs behind) idle=7a9/140000000000001/0 softirq=78438968/78438969 fqs=2[285165.804689] (t=60000 jiffies g=34009425 c=34009424 q=50872)[285165.810530] rcu_sched kthread starved for 60000 jiffies! g34009425 c...