On Mon, Apr 11, 2022 at 9:49 AM Uladzislau Rezki <urezki@xxxxxxxxx> wrote: > > Hello, Joel. > > > On systems with CONFIG_RCU_NOCB_CPU=y, there is no default mask provided > > which ends up not offloading any CPU. This patch removes yet another > > dependency from the bootloader having to know about RCU, about how many > > CPUs the system has, and about how to provide the mask. Basically, I > > think we should stop pretending that the user knows what they are doing :). > > In other words, if NO_CB_CPU is enabled, lets make use of it. > > > Could you also please modify the documentation accordingly and send v2? Yes good point, I can go clean that up in v2. - Joel > <snip> > urezki@pc638:~/data/raid0/coding/linux-rcu.git$ grep -rn RCU_NOCB_CPU ./Documentation/ > ./Documentation/timers/no_hz.rst:188:using the CONFIG_RCU_NOCB_CPU=y Kconfig option. The specific CPUs to > ./Documentation/admin-guide/kernel-parameters.txt:4380: In kernels built with CONFIG_RCU_NOCB_CPU=y, > ./Documentation/admin-guide/kernel-parameters.txt:4507: When RCU_NOCB_CPU is set, also adjust the > ./Documentation/admin-guide/kernel-per-CPU-kthreads.rst:311:3. Build with CONFIG_RCU_NOCB_CPU=y and boot with the rcu_nocbs= > ./Documentation/admin-guide/kernel-per-CPU-kthreads.rst:331:2. Build with CONFIG_RCU_NOCB_CPU=n, which will prevent these > ./Documentation/RCU/Design/Requirements/Requirements.rst:1424:``CONFIG_RCU_NOCB_CPU=y`` and booted with ``rcu_nocbs=1-63``, where > urezki@pc638:~/data/raid0/coding/linux-rcu.git$ grep -rn RCU_NOCB_CPU ./kernel/rcu/ > ... > ./kernel/rcu/Kconfig:198:config RCU_NOCB_CPU > .. > <snip> > > -- > Uladzislau Rezki
