On Tue, Aug 18, 2020 at 11:53 AM Dave Hansen <[email protected]> wrote: > > > From: Yang Shi <[email protected]> > > Account the number of demoted pages into reclaim_state->nr_demoted. > > Add pgdemote_kswapd and pgdemote_direct VM counters showed in > /proc/vmstat.
BTW we'd better add promotion counters as well. The NUMA balancing could promote pages to local nodes without any modification. We could argue it may be optimized for PMEM usecases, but it does work. And it makes the patchset more self-contained. You could refer to: https://lore.kernel.org/linux-mm/[email protected]/ > > [ daveh: > - __count_vm_events() a bit, and made them look at the THP > size directly rather than getting data from migrate_pages() > ] > > Signed-off-by: Yang Shi <[email protected]> > Signed-off-by: Dave Hansen <[email protected]> > Cc: David Rientjes <[email protected]> > Cc: Huang Ying <[email protected]> > Cc: Dan Williams <[email protected]> > --- > > b/include/linux/vm_event_item.h | 2 ++ > b/mm/vmscan.c | 6 ++++++ > b/mm/vmstat.c | 2 ++ > 3 files changed, 10 insertions(+) > > diff -puN include/linux/vm_event_item.h~mm-vmscan-add-page-demotion-counter > include/linux/vm_event_item.h > --- a/include/linux/vm_event_item.h~mm-vmscan-add-page-demotion-counter > 2020-08-18 11:36:54.062583176 -0700 > +++ b/include/linux/vm_event_item.h 2020-08-18 11:36:54.070583176 -0700 > @@ -32,6 +32,8 @@ enum vm_event_item { PGPGIN, PGPGOUT, PS > PGREFILL, > PGSTEAL_KSWAPD, > PGSTEAL_DIRECT, > + PGDEMOTE_KSWAPD, > + PGDEMOTE_DIRECT, > PGSCAN_KSWAPD, > PGSCAN_DIRECT, > PGSCAN_DIRECT_THROTTLE, > diff -puN mm/vmscan.c~mm-vmscan-add-page-demotion-counter mm/vmscan.c > --- a/mm/vmscan.c~mm-vmscan-add-page-demotion-counter 2020-08-18 > 11:36:54.064583176 -0700 > +++ b/mm/vmscan.c 2020-08-18 11:36:54.072583176 -0700 > @@ -147,6 +147,7 @@ struct scan_control { > unsigned int immediate; > unsigned int file_taken; > unsigned int taken; > + unsigned int demoted; > } nr; > > /* for recording the reclaimed slab by now */ > @@ -1146,6 +1147,11 @@ static unsigned int demote_page_list(str > list_splice(ret_list, demote_pages); > } > > + if (current_is_kswapd()) > + __count_vm_events(PGDEMOTE_KSWAPD, nr_succeeded); > + else > + __count_vm_events(PGDEMOTE_DIRECT, nr_succeeded); > + > return nr_succeeded; > } > > diff -puN mm/vmstat.c~mm-vmscan-add-page-demotion-counter mm/vmstat.c > --- a/mm/vmstat.c~mm-vmscan-add-page-demotion-counter 2020-08-18 > 11:36:54.067583176 -0700 > +++ b/mm/vmstat.c 2020-08-18 11:36:54.072583176 -0700 > @@ -1200,6 +1200,8 @@ const char * const vmstat_text[] = { > "pgrefill", > "pgsteal_kswapd", > "pgsteal_direct", > + "pgdemote_kswapd", > + "pgdemote_direct", > "pgscan_kswapd", > "pgscan_direct", > "pgscan_direct_throttle", > _
