Hello! At Linus's request, I am simplifying the Linux-kernel RCU implementation, which includes removing code that implements features and options that are no longer needed. This is not a half-hearted effort. In fact, I expect that my submission to the next merge window will be a net removal of more than 2500 lines of code. But wait, there is more! ;-) Although the following two features are not being axed in v4.13, they will be in v4.14 unless someone makes a convincing case for them: 1. The ability to build a CONFIG_RCU_NOCB_CPUS=y kernel without also specifying CONFIG_NO_HZ_FULL. Unless someone speaks for this configuration option, CONFIG_RCU_NOCB_CPUS will be slaved off of CONFIG_NO_HZ_FULL, and the rcu_nocbs= boot parameter will be dropped. (RCU would instead use the nohz_full= boot parameter to determine which CPUs get their callbacks offloaded.) 2. The ability to specify polling for callback-offloaded CPUs. This means that the rcu_nocb_poll= boot parameter will be dropped, and the CPU doing call_rcu() would do explicit wakeups, when needed, to get the corresponding rcuo kthread on the job. I have no evidence that anyone has ever used this option, other than me running the occasional rcutorture test. So, anyone need either of these? If not, out they go! ;-) Thanx, Paul -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
