On Thu, May 29, 2014 at 09:07:44AM -0500, Christoph Lameter wrote: > On Thu, 29 May 2014, Frederic Weisbecker wrote: > > > The cpumasks in cpu.c are special as they are the base of the cpumask_var_t > > definition. They are necessary to define nr_cpu_bits which is the base of > > cpumask_var_t allocations. As such they must stay lower level and defined > > on top of NR_CPUS. > > > > But most other cases don't need that huge static bitmap. I actually haven't > > seen any other struct cpumask than isn't based on cpumask_var_t. > > Well yes and I am tying directly into that scheme there in cpu.c to > display the active vmstat threads in sysfs. so its the same. I don't think so. Or is there something in vmstat that cpumask_var_t definition depends upon? > > > Please post it on a new thread so it gets noticed by others. > > Ok. Will do when we got agreement on the cpumask issue. > > I would like to have some way to display the activities on cpus in /sysfs > like I have done here with the active vmstat workers. > > What I think we need is display cpumasks for > > 1. Cpus where the tick is currently off > 2. Cpus that have dynticks enabled. > 3. Cpus that are idle You should find all that in /proc/timer_list Now for CPUs that have full dynticks enabled, we probably need something in sysfs. We could dump the nohz cpumask somewhere. For now you can only grep the dmesg > 4. Cpus that are used for RCU. So, you mean those that aren't in extended grace period (between rcu_user_enter()/exit or rcu_idle_enter/exit)? Paul? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>