On Thu, Oct 22, 2015 at 12:21:35AM -0400, Johannes Weiner wrote: ... > @@ -2437,6 +2439,10 @@ static bool shrink_zone(struct zone *zone, struct scan_control *sc, > } > } > > + vmpressure(sc->gfp_mask, memcg, > + sc->nr_scanned - scanned, > + sc->nr_reclaimed - reclaimed); > + > /* > * Direct reclaim and kswapd have to scan all memory > * cgroups to fulfill the overall scan target for the > @@ -2454,10 +2460,6 @@ static bool shrink_zone(struct zone *zone, struct scan_control *sc, > } > } while ((memcg = mem_cgroup_iter(root, memcg, &reclaim))); > > - vmpressure(sc->gfp_mask, sc->target_mem_cgroup, > - sc->nr_scanned - nr_scanned, > - sc->nr_reclaimed - nr_reclaimed); > - > if (sc->nr_reclaimed - nr_reclaimed) > reclaimable = true; > I may be mistaken, but AFAIU this patch subtly changes the behavior of vmpressure visible from the userspace: w/o this patch a userspace process will only receive a notification for a memory cgroup only if *this* memory cgroup calls reclaimer; with this patch userspace notification will be issued even if reclaimer is invoked by any cgroup up the hierarchy. Thanks, Vladimir -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>