> Maybe we should add another member to record jiffies. > > diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c > index b33165dba1ea745..6d9c876ea5c85a6 100644 > --- a/kernel/rcu/tree.c > +++ b/kernel/rcu/tree.c > @@ -880,6 +880,7 @@ static int rcu_implicit_dynticks_qs(struct rcu_data > *rdp) > rsrp->nr_hardirqs = kstat_cpu_irqs_sum(rdp->cpu); > rsrp->nr_softirqs = kstat_cpu_softirqs_sum(rdp- > >cpu); > rsrp->nr_csw = nr_context_switches_cpu(rdp->cpu); > + rsrp->jiffies = jiffies; > rsrp->gp_seq = rdp->gp_seq; Yes, that works: [ 252.139108] tcrypt: rcu testing - kernel_fpu_disable for rude 22 s [ 255.140204] rcu: INFO: rcu_preempt self-detected stall on CPU 39 [ 255.146438] rcu: CPU 39-....: (2995 ticks this GP) idle=5014/1/0x4000000000000000 softirq=2373/2374 fqs=751 [ 255.156512] rcu: CPU 39 hardirqs softirqs csw system cond_resched [ 255.165182] rcu: CPU 39 count: 0 3 0 0 [ 255.173853] rcu: CPU 39 cputime: 3 0 1493 ==> 1530 (ms) [ 255.183746] rcu: CPU 39 current: in_kernel_fpu_begin=1 preemptible=0 [ 255.190407] rcu: CPU 39 self-detected stall t=3051 jiffies g=18181 q=373 ncpus=56 [ 255.198205] CPU: 39 PID: 2607 Comm: modprobe Not tainted 6.0.0+ #14 ... [ 264.450164] rcu: INFO: rcu_preempt self-detected stall on CPU 39 [ 264.456416] rcu: CPU 39-...k.: (12000 ticks this GP) idle=5014/1/0x4000000000000000 softirq=2373/2374 fqs=3006 [ 264.466690] rcu: CPU 39 hardirqs softirqs csw system cond_resched [ 264.475390] rcu: CPU 39 count: 0 21 0 0 [ 264.484092] rcu: CPU 39 cputime: 328 0 8982 ==> 9293 (ms) [ 264.494015] rcu: CPU 39 current: in_kernel_fpu_begin=1 preemptible=0 [ 264.500706] rcu: CPU 39 self-detected stall t=12361 jiffies g=18181 q=601 ncpus=56 [ 264.508619] CPU: 39 PID: 2607 Comm: modprobe Not tainted 6.0.0+ #14 ... [ 273.760124] rcu: INFO: rcu_preempt self-detected stall on CPU 39 [ 273.766376] rcu: CPU 39-....: (21004 ticks this GP) idle=5014/1/0x4000000000000000 softirq=2373/2374 fqs=5262 [ 273.776649] rcu: CPU 39 hardirqs softirqs csw system cond_resched [ 273.785348] rcu: CPU 39 count: 0 17 0 0 [ 273.794050] rcu: CPU 39 cputime: 328 0 8981 ==> 9293 (ms) [ 273.803971] rcu: CPU 39 current: in_kernel_fpu_begin=1 preemptible=0 [ 273.810660] rcu: CPU 39 self-detected stall t=21671 jiffies g=18181 q=1112 ncpus=56 [ 273.818659] CPU: 39 PID: 2607 Comm: modprobe Not tainted 6.0.0+ #14
