On 14.03.2011 18:17, Kurt Van Dijck wrote: > On Mon, Mar 14, 2011 at 05:42:23PM +0100, Eric Dumazet wrote: >> Le lundi 14 mars 2011 à 16:02 +0100, Kurt Van Dijck a écrit : >> >>> I see your point. >>> The reason I modified this was, as described, checkpatch.pl was complaining. >>> Anyway, this sequence was protected by a spinlock 'proto_tab_lock'. >>> I don't think it was a race. >>> >>> Did I miss something? >> >> As soon as proto_tab[proto] = cp; is done, another thread on another cpu >> can read the pointer and follow it. >> >> Hmm, I missed can_create() also uses the spinlock protection, so you're >> probably right. >> >> It seems a bit overkill :( >> phonet uses RCU for example.
Hello Eric, the RCU code in phonet is worth to consider. But loading and removing of protocols is far away from being a hot path ... what would be the advantages to move to RCU here? > I'll keep that in mind. > Switching CAN protos to RCU is far beyond to goal of this patch :-) Anyway making the struct proto a const (and set the default defines in the CAN protocols) is a nice cleanup. Let's wait for the feedback about the RCU from Eric ... then this patch could be put into mainline independently from the j1939 protocol. Thanks, Oliver _______________________________________________ Socketcan-core mailing list [email protected] https://lists.berlios.de/mailman/listinfo/socketcan-core
