On Tue, Oct 22, 2019 at 05:42:49PM -0400, Johannes Weiner wrote: > On Tue, Oct 22, 2019 at 07:56:33PM +0000, Roman Gushchin wrote: > > On Tue, Oct 22, 2019 at 10:48:00AM -0400, Johannes Weiner wrote: > > > - /* Record the group's reclaim efficiency */ > > > - vmpressure(sc->gfp_mask, memcg, false, > > > - sc->nr_scanned - scanned, > > > - sc->nr_reclaimed - reclaimed); > > > - > > > - } while ((memcg = mem_cgroup_iter(root, memcg, NULL))); > > > + reclaimed = sc->nr_reclaimed; > > > + scanned = sc->nr_scanned; > > > + shrink_node_memcg(pgdat, memcg, sc); > > > > > > - if (reclaim_state) { > > > - sc->nr_reclaimed += reclaim_state->reclaimed_slab; > > > - reclaim_state->reclaimed_slab = 0; > > > - } > > > + shrink_slab(sc->gfp_mask, pgdat->node_id, memcg, > > > + sc->priority); > > > > > > - /* Record the subtree's reclaim efficiency */ > > > - vmpressure(sc->gfp_mask, sc->target_mem_cgroup, true, > > > - sc->nr_scanned - nr_scanned, > > > - sc->nr_reclaimed - nr_reclaimed); > > > + /* Record the group's reclaim efficiency */ > > > + vmpressure(sc->gfp_mask, memcg, false, > > > + sc->nr_scanned - scanned, > > > + sc->nr_reclaimed - reclaimed); > > > > It doesn't look as a trivial change. I'd add some comments to the commit message > > why it's safe to do. > > It's an equivalent change - it's just really misleading because the > +++ lines are not the counter-part of the --- lines here! > > There are two vmpressure calls in this function: one against the > individual cgroups, and one against the tree. The diff puts them > adjacent here, but the counter-part for the --- lines is here: > > > > + /* Record the subtree's reclaim efficiency */ > > > + vmpressure(sc->gfp_mask, sc->target_mem_cgroup, true, > > > + sc->nr_scanned - nr_scanned, > > > + sc->nr_reclaimed - nr_reclaimed); > > And the counter-part to the +++ lines is further up (beginning of the > quoted diff). > Ah, ok, got it. You were right in the foreword, indentation change diffs are hard to read. Thanks for the explanation! Reviewed-by: Roman Gushchin <guro@xxxxxx>