On Thu, Apr 13, 2023 at 04:32:32PM +0100, Rui Salvaterra wrote: > Hi, Paul, > > On Thu, 13 Apr 2023 at 15:43, Paul E. McKenney <paulmck@xxxxxxxxxx> wrote: > > > > My guess would be that you have CONFIG_RCU_EXP_CPU_STALL_TIMEOUT set to > > some small non-zero number, for example, you might have set up a recent > > Android .config or some such. The default of zero would give you about > > 21 seconds rather than the three jiffies that you are seeing. > > > > Could you please check your .config? > > Well, this is embarrassing. I can't fathom why/how, but I had it set > to 20, on this machine. That is, 20 millisseconds. I guess its a > miracle I haven't seen *more* expedited RCU traces. Sorry for the > noise, everyone. Been there, done that! And actually, it is kind of reassuring that the Linux kernel avoids tens-of-milliseocnds latency blows in the common case on your system. Thanx, Paul