On 2022/8/5 2:09, Paul E. McKenney wrote: > On Thu, Aug 04, 2022 at 10:34:18AM +0800, Zhen Lei wrote: >> v3 --> v4: >> 1. To avoid undo/redo, merge patch 1-2 in v3 into one. >> >> v2 --> v3: >> 1. Patch 1 Add trigger_single_cpu_backtrace(cpu) in synchronize_rcu_expedited_wait() >> Subsequently, we can see that all callers of dump_cpu_task() try >> trigger_single_cpu_backtrace() first. Then I do the cleanup in Patch 2. >> 2. Patch 3, as Paul E. McKenney's suggestion, push the code into dump_cpu_task(). >> >> For newcomers: >> Currently, dump_cpu_task() is mainly used by RCU, in order to dump the >> stack traces of the current task of the specified CPU when a rcu stall >> is detected. >> >> For architectures that do not support NMI interrupts, registers is not >> printed when rcu stall is self-detected. This patch series improve it. > > Thank you! I have queued both for further testing and review. I had > to rebase them to the -rcu tree's "dev" branch. There was one trivial > conflict, but could you please check the resulting commits, both for > my wordsmithing and to make sure that your changes still work in your > environment? (I do not have access to that sort of hardware.) Your description is much clearer than mine, thanks. I will test it tomorrow, the international network speed is too slow during the day. > > In the future, could you please send your patches against the -rcu > tree's "dev" branch? Okay, no problem. I'll do it next time. > > Thanx, Paul > >> v2: >> https://lkml.org/lkml/2022/7/27/1800 >> >> Zhen Lei (2): >> sched/debug: Try trigger_single_cpu_backtrace(cpu) in dump_cpu_task() >> sched/debug: Show the registers of 'current' in dump_cpu_task() >> >> kernel/rcu/tree_stall.h | 8 +++----- >> kernel/sched/core.c | 14 ++++++++++++++ >> kernel/smp.c | 3 +-- >> 3 files changed, 18 insertions(+), 7 deletions(-) >> >> -- >> 2.25.1 >> > . > -- Regards, Zhen Lei
