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That > needs more time to bake. > It makes sense to look at it and then decide if it makes sense. > > > > > > page = alloc_pages_node(nid, __GFP_PRIVATE, 0); > > > > Do we want to provide kernel level control over allocation of private > > pages, I assumed that only user space applications? I would assume > > node affinity would be the way to do so, unless we have multiple > > > > alloc_pages_node() is the kernel interface I was think we wouldn't need explicit flags and that allocations would happen from user space using __GFP_THISNODE to the node or via a nodemask based on nodes of interest. Is there a reason to add this flag, a system might have more than one source of N_MEMORY_PRIVATE? > > > > > > > /* Ok but I want to do something useful with it */ > > > static const struct node_private_ops ops = { > > > .migrate_to = my_migrate_to, > > > .folio_migrate = my_folio_migrate, > > > .flags = NP_OPS_MIGRATION | NP_OPS_MEMPOLICY, > > > }; > > > node_private_set_ops(nid, &ops); > > > > > > > Could you explain this further? Why does OPS_MIGRATION > > and OPS_MEMPOLICY needs to be set explictly? > > > > Both of these have been removed from the upcoming version, but in this > RFC version i was testing OPS_MIGRATION as an explicit flag that meant > "migrate.c can touch the folios" while OPS_MEMPOLICY meant "mempolicy.c > can touch the folios". > > As it turns out, OPS_MIGRATION is not a useful filter, as it doesn't > actually filter anything (anything using OPS_MIGRATION would also need > its own filter flag, so better to just drop it and do per-server > opt-ins). > Thanks, Balbir