Gregory Price <gourry@xxxxxxxxxx> writes: > On Tue, Jan 21, 2025 at 07:17:15PM +0800, Huang, Ying wrote: > ... snip ... >> >> Unless it's possible we will add more modes in the future, this is kind >> of overkill for me. How about something simpler as below? >> >> $ cat auto >> true >> $ echo 0 > auto >> $ cat auto >> false > > We have discussed having a dynamic-mode where the weights might adjust > on the fly based on system-state, but i think this ends up being > controlled under mempolicy/dynamic_interleave or something. > > So this seems reasonable. > >> > static u8 __rcu *iw_table; >> > static DEFINE_MUTEX(iw_table_lock); >> > +static const int weightiness = 32; >> > +static bool weighted_interleave_auto = true; >> >> I still prefer to use 2 iw_table, one is for default, the other is for >> manual. The default one will be used if the manual one is NULL. Both >> are protected by RCU. The default one can be updated upon hotplug >> blindly. This makes the whole model easier to be understood IMHO. >> >> What do you think about that. >> > > only question is, lets say you have > > `cat auto node0 node1` -> `true 5 1` > and you do > echo 0 > auto > > what should a subsequent `cat auto node0 node1` output? > > `false 5 1` > or > `false 1 1` IMO, it should be `false 5 1` That is, we copy auto-generated weights to manual weights atomically and use it. > Then lets say we do > echo 7 > node0 Now, `cat auto node0 node1` outputs, `false 7 1` That is, we delete manual weights and use the auto-generated ones. > what should > echo true > auto > result in? > > `true 5 1` > or > `true 7 1` It should be `true 5 1` > The current code makes sure that when you switch modes from auto > to manual, it inherits the current state - instead of there being > some hidden state that suddenly takes precedence. I think that we can do that with two weight arrays. > So I prefer to just have one IW array and no hidden state. Then, when we switch from manual to auto mode, where to find auto-generated weights? Re-calculate them? --- Best Regards, Huang, Ying
