* Lai Jiangshan ([email protected]) wrote: > rculfstack is not really require RCU-only. > > 1) cds_lfs_push_rcu() don't need any lock, don't need RCU nor other locks.
Good point ! I even documented this peculiarness in the comment at the top of _cds_lfs_push_rcu(). > 2) cds_lfs_pop_rcu() don't only one of the following synchronization(not only > RCU): > A) use rcu_read_lock() to protect cds_lfs_pop_rcu() and use > synchronize_rcu() > or call_rcu() to free the popped node. (current comments said we > need this > synchronization, and thus we named this struct with rcu prefix. > But actually, > the followings are OK, and are more popular/friendly) > B) use mutexs/locks to protect cds_lfs_pop_rcu(), we can free to > free/modify the > popped node any time, we don't need any synchronization when free > them. > C) only ONE thread can call cds_lfs_pop_rcu(). (multi-providers-single > customer) > D) others, like read-write locks. > > I consider B) and C) are more popular. In linux kernel, > kernel/task_work.c uses a hybird ways of B) and C). > > I suggest to rename it, Or document B) and C) at least. Yes, agreed! Do you suggest we introduce a "lfstack", and slowly deprecate rculfstack ? We could then document the various ways to protect "pop", and also implement a "splice" operation while we are there. Thoughts ? Thanks, Mathieu > > Thanks, > Lai > > _______________________________________________ > lttng-dev mailing list > [email protected] > http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev -- Mathieu Desnoyers Operating System Efficiency R&D Consultant EfficiOS Inc. http://www.efficios.com _______________________________________________ lttng-dev mailing list [email protected] http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
