On Tue, Apr 30, 2024 at 1:34 AM Yosry Ahmed <yosryahmed@xxxxxxxxxx> wrote: > > On Mon, Apr 29, 2024 at 11:06 PM Shakeel Butt <shakeel.butt@xxxxxxxxx> wrote: > > > > mem_cgroup_events_index is a translation table to get the right index of > > the memcg relevant entry for the general vm_event_item. At the moment, > > it is defined as integer array. However on a typical system the max > > entry of vm_event_item (NR_VM_EVENT_ITEMS) is 113, so we don't need to > > use int as storage type of the array. For now just use int8_t as type > > and add a BUILD_BUG_ON() and will switch to short once NR_VM_EVENT_ITEMS > > touches 127. > > > > Another benefit of this change is that the translation table fits in 2 > > cachelines while previously it would require 8 cachelines (assuming 64 > > bytes cachesline). > > > > Signed-off-by: Shakeel Butt <shakeel.butt@xxxxxxxxx> > > Reviewed-by: Roman Gushchin <roman.gushchin@xxxxxxxxx> > > Reviewed-by: Yosry Ahmed <yosryahmed@xxxxxxxxxx> > Reviewed-by: T.J. Mercier <tjmercier@xxxxxxxxxx>
