On Fri, Nov 06, 2020 at 03:48:16PM +0800, Alex Shi wrote: > From 84e69f892119d99612e9668e3fe47a3922bafff1 Mon Sep 17 00:00:00 2001 > From: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx> > Date: Tue, 18 Aug 2020 16:44:21 +0800 > Subject: [PATCH v21 17/19] mm/lru: replace pgdat lru_lock with lruvec lock > > This patch moves per node lru_lock into lruvec, thus bring a lru_lock for > each of memcg per node. So on a large machine, each of memcg don't > have to suffer from per node pgdat->lru_lock competition. They could go > fast with their self lru_lock. > > After move memcg charge before lru inserting, page isolation could > serialize page's memcg, then per memcg lruvec lock is stable and could > replace per node lru lock. > > In func isolate_migratepages_block, compact_unlock_should_abort and > lock_page_lruvec_irqsave are open coded to work with compact_control. > Also add a debug func in locking which may give some clues if there are > sth out of hands. > > Daniel Jordan's testing show 62% improvement on modified readtwice case > on his 2P * 10 core * 2 HT broadwell box. > https://lore.kernel.org/lkml/20200915165807.kpp7uhiw7l3loofu@xxxxxxxxxxxxxxxxxxxxxxxxxx/ > > On a large machine with memcg enabled but not used, the page's lruvec > seeking pass a few pointers, that may lead to lru_lock holding time > increase and a bit regression. > > Hugh Dickins helped on the patch polish, thanks! > > Signed-off-by: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx> > Acked-by: Hugh Dickins <hughd@xxxxxxxxxx> > Cc: Rong Chen <rong.a.chen@xxxxxxxxx> > Cc: Hugh Dickins <hughd@xxxxxxxxxx> > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > Cc: Johannes Weiner <hannes@xxxxxxxxxxx> > Cc: Michal Hocko <mhocko@xxxxxxxxxx> > Cc: Vladimir Davydov <vdavydov.dev@xxxxxxxxx> > Cc: Yang Shi <yang.shi@xxxxxxxxxxxxxxxxx> > Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> > Cc: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx> > Cc: Tejun Heo <tj@xxxxxxxxxx> > Cc: linux-kernel@xxxxxxxxxxxxxxx > Cc: linux-mm@xxxxxxxxx > Cc: cgroups@xxxxxxxxxxxxxxx Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
