On Tue, Mar 04, 2025 at 10:20:59AM +0100, Marco Elver wrote: > === Initial Uses === > > With this initial series, the following synchronization primitives are > supported: `raw_spinlock_t`, `spinlock_t`, `rwlock_t`, `mutex`, > `seqlock_t`, `bit_spinlock`, RCU, SRCU (`srcu_struct`), `rw_semaphore`, > `local_lock_t`, `ww_mutex`. Wasn't there a limitation wrt recursion -- specifically RCU is very much a recursive lock and TS didn't really fancy that? > - Rename __var_guarded_by to simply __guarded_by. Initially the idea > was to be explicit about if the variable itself or the pointed-to > data is guarded, but in the long-term, making this shorter might be > better. > > - Likewise rename __ref_guarded_by to __pt_guarded_by. Shorter is better :-) Anyway; I think I would like to start talking about extensions for these asap. Notably I feel like we should have a means to annotate the rules for access/read vs modify/write to a variable. The obvious case is RCU; where holding RCU is sufficient to read, but modification requires a 'real' lock. This is not something that can be currently expressed. The other is the lock pattern I touched upon the other day, where reading is permitted when holding one of two locks, while writing requires holding both locks. Being able to explicitly write that in the __guarded_by() annotations is the cleanest way I think. Anyway, let me go stare at the actual patches :-)
