Le Sun, Jul 06, 2025 at 11:32:08PM -0400, Joel Fernandes a écrit : > The synchronization of CPU offlining with GP initialization is confusing > to put it mildly (rightfully so as the issue it deals with is complex). > Recent discussions brought up a question -- what prevents the > rcu_implicit_dyntick_qs() from warning about QS reports for offline > CPUs (missing QS reports for offline CPUs causing indefinite hangs). > > QS reporting for now-offline CPUs should only happen from: > - gp_init() > - rcutree_cpu_report_dead() > > Add some documentation on this and refer to it from comments in the code > explaining how QS reporting is not missed when these functions are > concurrently running. > > I referred heavily to this post [1] about the need for the ofl_lock. > [1] https://lore.kernel.org/all/20180924164443.gf4...@linux.ibm.com/ > > [ Applied paulmck feedback on moving documentation to Requirements.rst ] > > Link: > https://lore.kernel.org/all/01b4d228-9416-43f8-a62e-124b92e8741a@paulmck-laptop/ > Co-developed-by: Paul E. McKenney <paul...@kernel.org> > Signed-off-by: Joel Fernandes <joelagn...@nvidia.com>
Very nice and welcome!!! Reviewed-by: Frederic Weisbecker <frede...@kernel.org> -- Frederic Weisbecker SUSE Labs
