* [PATCH] vmscan: reclaim_clean_pages_from_list() must count mlocked pages @ 2015-08-03 10:18 Jaewon Kim 2015-08-03 12:27 ` Minchan Kim 0 siblings, 1 reply; 6+ messages in thread From: Jaewon Kim @ 2015-08-03 10:18 UTC (permalink / raw) To: akpm; +Cc: mgorman, minchan, linux-mm, linux-kernel, jaewon31.kim, Jaewon Kim reclaim_clean_pages_from_list() decreases NR_ISOLATED_FILE by returned value from shrink_page_list(). But mlocked pages in the isolated clean_pages page list would be removed from the list but not counted as nr_reclaimed. Fix this miscounting by returning the number of mlocked pages and count it. Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com> --- mm/vmscan.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 5e8eadd..5837695 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -849,6 +849,7 @@ static unsigned long shrink_page_list(struct list_head *page_list, unsigned long *ret_nr_congested, unsigned long *ret_nr_writeback, unsigned long *ret_nr_immediate, + unsigned long *ret_nr_mlocked, bool force_reclaim) { LIST_HEAD(ret_pages); @@ -1158,6 +1159,7 @@ cull_mlocked: try_to_free_swap(page); unlock_page(page); putback_lru_page(page); + (*ret_nr_mlocked)++; continue; activate_locked: @@ -1197,6 +1199,7 @@ unsigned long reclaim_clean_pages_from_list(struct zone *zone, .may_unmap = 1, }; unsigned long ret, dummy1, dummy2, dummy3, dummy4, dummy5; + unsigned long nr_mlocked = 0; struct page *page, *next; LIST_HEAD(clean_pages); @@ -1210,8 +1213,10 @@ unsigned long reclaim_clean_pages_from_list(struct zone *zone, ret = shrink_page_list(&clean_pages, zone, &sc, TTU_UNMAP|TTU_IGNORE_ACCESS, - &dummy1, &dummy2, &dummy3, &dummy4, &dummy5, true); + &dummy1, &dummy2, &dummy3, &dummy4, &dummy5, + &nr_mlocked, true); list_splice(&clean_pages, page_list); + ret += nr_mlocked; mod_zone_page_state(zone, NR_ISOLATED_FILE, -ret); return ret; } @@ -1523,6 +1528,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, unsigned long nr_unqueued_dirty = 0; unsigned long nr_writeback = 0; unsigned long nr_immediate = 0; + unsigned long nr_mlocked = 0; isolate_mode_t isolate_mode = 0; int file = is_file_lru(lru); struct zone *zone = lruvec_zone(lruvec); @@ -1565,7 +1571,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, nr_reclaimed = shrink_page_list(&page_list, zone, sc, TTU_UNMAP, &nr_dirty, &nr_unqueued_dirty, &nr_congested, - &nr_writeback, &nr_immediate, + &nr_writeback, &nr_immediate, &nr_mlocked, false); spin_lock_irq(&zone->lru_lock); -- 1.9.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] vmscan: reclaim_clean_pages_from_list() must count mlocked pages 2015-08-03 10:18 [PATCH] vmscan: reclaim_clean_pages_from_list() must count mlocked pages Jaewon Kim @ 2015-08-03 12:27 ` Minchan Kim 2015-08-03 14:55 ` Jaewon Kim 0 siblings, 1 reply; 6+ messages in thread From: Minchan Kim @ 2015-08-03 12:27 UTC (permalink / raw) To: Jaewon Kim; +Cc: akpm, mgorman, linux-mm, linux-kernel, jaewon31.kim Hello, On Mon, Aug 03, 2015 at 07:18:27PM +0900, Jaewon Kim wrote: > reclaim_clean_pages_from_list() decreases NR_ISOLATED_FILE by returned > value from shrink_page_list(). But mlocked pages in the isolated > clean_pages page list would be removed from the list but not counted as > nr_reclaimed. Fix this miscounting by returning the number of mlocked > pages and count it. If there are pages not able to reclaim, VM try to migrate it and have to handle the stat in migrate_pages. If migrate_pages fails again, putback-fiends should handle it. Is there anyting I am missing now? Thanks. > > Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com> > --- > mm/vmscan.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index 5e8eadd..5837695 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -849,6 +849,7 @@ static unsigned long shrink_page_list(struct list_head *page_list, > unsigned long *ret_nr_congested, > unsigned long *ret_nr_writeback, > unsigned long *ret_nr_immediate, > + unsigned long *ret_nr_mlocked, > bool force_reclaim) > { > LIST_HEAD(ret_pages); > @@ -1158,6 +1159,7 @@ cull_mlocked: > try_to_free_swap(page); > unlock_page(page); > putback_lru_page(page); > + (*ret_nr_mlocked)++; > continue; > > activate_locked: > @@ -1197,6 +1199,7 @@ unsigned long reclaim_clean_pages_from_list(struct zone *zone, > .may_unmap = 1, > }; > unsigned long ret, dummy1, dummy2, dummy3, dummy4, dummy5; > + unsigned long nr_mlocked = 0; > struct page *page, *next; > LIST_HEAD(clean_pages); > > @@ -1210,8 +1213,10 @@ unsigned long reclaim_clean_pages_from_list(struct zone *zone, > > ret = shrink_page_list(&clean_pages, zone, &sc, > TTU_UNMAP|TTU_IGNORE_ACCESS, > - &dummy1, &dummy2, &dummy3, &dummy4, &dummy5, true); > + &dummy1, &dummy2, &dummy3, &dummy4, &dummy5, > + &nr_mlocked, true); > list_splice(&clean_pages, page_list); > + ret += nr_mlocked; > mod_zone_page_state(zone, NR_ISOLATED_FILE, -ret); > return ret; > } > @@ -1523,6 +1528,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, > unsigned long nr_unqueued_dirty = 0; > unsigned long nr_writeback = 0; > unsigned long nr_immediate = 0; > + unsigned long nr_mlocked = 0; > isolate_mode_t isolate_mode = 0; > int file = is_file_lru(lru); > struct zone *zone = lruvec_zone(lruvec); > @@ -1565,7 +1571,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, > > nr_reclaimed = shrink_page_list(&page_list, zone, sc, TTU_UNMAP, > &nr_dirty, &nr_unqueued_dirty, &nr_congested, > - &nr_writeback, &nr_immediate, > + &nr_writeback, &nr_immediate, &nr_mlocked, > false); > > spin_lock_irq(&zone->lru_lock); > -- > 1.9.1 > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] vmscan: reclaim_clean_pages_from_list() must count mlocked pages 2015-08-03 12:27 ` Minchan Kim @ 2015-08-03 14:55 ` Jaewon Kim 2015-08-03 15:33 ` Minchan Kim 0 siblings, 1 reply; 6+ messages in thread From: Jaewon Kim @ 2015-08-03 14:55 UTC (permalink / raw) To: Minchan Kim; +Cc: akpm, mgorman, linux-mm, linux-kernel, jaewon31.kim On 2015e?? 08i?? 03i? 1/4 21:27, Minchan Kim wrote: > Hello, > > On Mon, Aug 03, 2015 at 07:18:27PM +0900, Jaewon Kim wrote: >> reclaim_clean_pages_from_list() decreases NR_ISOLATED_FILE by returned >> value from shrink_page_list(). But mlocked pages in the isolated >> clean_pages page list would be removed from the list but not counted as >> nr_reclaimed. Fix this miscounting by returning the number of mlocked >> pages and count it. > > If there are pages not able to reclaim, VM try to migrate it and > have to handle the stat in migrate_pages. > If migrate_pages fails again, putback-fiends should handle it. > > Is there anyting I am missing now? > > Thanks. > Hello Only pages in cc->migratepages will be handled by migrate_pages or putback_movable_pages, and NR_ISOLATED_FILE will be counted properly. However mlocked pages will not be put back into cc->migratepages, and also not be counted in NR_ISOLATED_FILE because putback_lru_page in shrink_page_list does not increase NR_ISOLATED_FILE. The current reclaim_clean_pages_from_list assumes that shrink_page_list returns number of pages removed from the candidate list. i.e) isolate_migratepages_range : NR_ISOLATED_FILE += 10 reclaim_clean_pages_from_list : NR_ISOLATED_FILE -= 5 (1 mlocked page) migrate_pages : NR_ISOLATED_FILE -=4 => NR_ISOLATED_FILE increased by 1 Thank you. >> >> Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com> >> --- >> mm/vmscan.c | 10 ++++++++-- >> 1 file changed, 8 insertions(+), 2 deletions(-) >> >> diff --git a/mm/vmscan.c b/mm/vmscan.c >> index 5e8eadd..5837695 100644 >> --- a/mm/vmscan.c >> +++ b/mm/vmscan.c >> @@ -849,6 +849,7 @@ static unsigned long shrink_page_list(struct list_head *page_list, >> unsigned long *ret_nr_congested, >> unsigned long *ret_nr_writeback, >> unsigned long *ret_nr_immediate, >> + unsigned long *ret_nr_mlocked, >> bool force_reclaim) >> { >> LIST_HEAD(ret_pages); >> @@ -1158,6 +1159,7 @@ cull_mlocked: >> try_to_free_swap(page); >> unlock_page(page); >> putback_lru_page(page); >> + (*ret_nr_mlocked)++; >> continue; >> >> activate_locked: >> @@ -1197,6 +1199,7 @@ unsigned long reclaim_clean_pages_from_list(struct zone *zone, >> .may_unmap = 1, >> }; >> unsigned long ret, dummy1, dummy2, dummy3, dummy4, dummy5; >> + unsigned long nr_mlocked = 0; >> struct page *page, *next; >> LIST_HEAD(clean_pages); >> >> @@ -1210,8 +1213,10 @@ unsigned long reclaim_clean_pages_from_list(struct zone *zone, >> >> ret = shrink_page_list(&clean_pages, zone, &sc, >> TTU_UNMAP|TTU_IGNORE_ACCESS, >> - &dummy1, &dummy2, &dummy3, &dummy4, &dummy5, true); >> + &dummy1, &dummy2, &dummy3, &dummy4, &dummy5, >> + &nr_mlocked, true); >> list_splice(&clean_pages, page_list); >> + ret += nr_mlocked; >> mod_zone_page_state(zone, NR_ISOLATED_FILE, -ret); >> return ret; >> } >> @@ -1523,6 +1528,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, >> unsigned long nr_unqueued_dirty = 0; >> unsigned long nr_writeback = 0; >> unsigned long nr_immediate = 0; >> + unsigned long nr_mlocked = 0; >> isolate_mode_t isolate_mode = 0; >> int file = is_file_lru(lru); >> struct zone *zone = lruvec_zone(lruvec); >> @@ -1565,7 +1571,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, >> >> nr_reclaimed = shrink_page_list(&page_list, zone, sc, TTU_UNMAP, >> &nr_dirty, &nr_unqueued_dirty, &nr_congested, >> - &nr_writeback, &nr_immediate, >> + &nr_writeback, &nr_immediate, &nr_mlocked, >> false); >> >> spin_lock_irq(&zone->lru_lock); >> -- >> 1.9.1 >> > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] vmscan: reclaim_clean_pages_from_list() must count mlocked pages 2015-08-03 14:55 ` Jaewon Kim @ 2015-08-03 15:33 ` Minchan Kim 2015-08-03 15:46 ` Jaewon Kim 0 siblings, 1 reply; 6+ messages in thread From: Minchan Kim @ 2015-08-03 15:33 UTC (permalink / raw) To: Jaewon Kim; +Cc: akpm, mgorman, linux-mm, linux-kernel, jaewon31.kim On Mon, Aug 03, 2015 at 11:55:46PM +0900, Jaewon Kim wrote: > > > On 2015e?? 08i?? 03i? 1/4 21:27, Minchan Kim wrote: > > Hello, > > > > On Mon, Aug 03, 2015 at 07:18:27PM +0900, Jaewon Kim wrote: > >> reclaim_clean_pages_from_list() decreases NR_ISOLATED_FILE by returned > >> value from shrink_page_list(). But mlocked pages in the isolated > >> clean_pages page list would be removed from the list but not counted as > >> nr_reclaimed. Fix this miscounting by returning the number of mlocked > >> pages and count it. > > > > If there are pages not able to reclaim, VM try to migrate it and > > have to handle the stat in migrate_pages. > > If migrate_pages fails again, putback-fiends should handle it. > > > > Is there anyting I am missing now? > > > > Thanks. > > > Hello > > Only pages in cc->migratepages will be handled by migrate_pages or > putback_movable_pages, and NR_ISOLATED_FILE will be counted properly. > However mlocked pages will not be put back into cc->migratepages, > and also not be counted in NR_ISOLATED_FILE because putback_lru_page > in shrink_page_list does not increase NR_ISOLATED_FILE. > The current reclaim_clean_pages_from_list assumes that shrink_page_list > returns number of pages removed from the candidate list. > > i.e) > isolate_migratepages_range : NR_ISOLATED_FILE += 10 > reclaim_clean_pages_from_list : NR_ISOLATED_FILE -= 5 (1 mlocked page) > migrate_pages : NR_ISOLATED_FILE -=4 > => NR_ISOLATED_FILE increased by 1 Thanks for the clarity. I think the problem is shrink_page_list is awkard. It put back to unevictable pages instantly instead of passing it to caller while it relies on caller for non-reclaimed-non-unevictable page's putback. I think we can make it consistent so that shrink_page_list could return non-reclaimed pages via page_list and caller can handle it. As a bonus, it could try to migrate mlocked pages without retrial. > > Thank you. > >> > >> Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com> > >> --- > >> mm/vmscan.c | 10 ++++++++-- > >> 1 file changed, 8 insertions(+), 2 deletions(-) > >> > >> diff --git a/mm/vmscan.c b/mm/vmscan.c > >> index 5e8eadd..5837695 100644 > >> --- a/mm/vmscan.c > >> +++ b/mm/vmscan.c > >> @@ -849,6 +849,7 @@ static unsigned long shrink_page_list(struct list_head *page_list, > >> unsigned long *ret_nr_congested, > >> unsigned long *ret_nr_writeback, > >> unsigned long *ret_nr_immediate, > >> + unsigned long *ret_nr_mlocked, > >> bool force_reclaim) > >> { > >> LIST_HEAD(ret_pages); > >> @@ -1158,6 +1159,7 @@ cull_mlocked: > >> try_to_free_swap(page); > >> unlock_page(page); > >> putback_lru_page(page); > >> + (*ret_nr_mlocked)++; > >> continue; > >> > >> activate_locked: > >> @@ -1197,6 +1199,7 @@ unsigned long reclaim_clean_pages_from_list(struct zone *zone, > >> .may_unmap = 1, > >> }; > >> unsigned long ret, dummy1, dummy2, dummy3, dummy4, dummy5; > >> + unsigned long nr_mlocked = 0; > >> struct page *page, *next; > >> LIST_HEAD(clean_pages); > >> > >> @@ -1210,8 +1213,10 @@ unsigned long reclaim_clean_pages_from_list(struct zone *zone, > >> > >> ret = shrink_page_list(&clean_pages, zone, &sc, > >> TTU_UNMAP|TTU_IGNORE_ACCESS, > >> - &dummy1, &dummy2, &dummy3, &dummy4, &dummy5, true); > >> + &dummy1, &dummy2, &dummy3, &dummy4, &dummy5, > >> + &nr_mlocked, true); > >> list_splice(&clean_pages, page_list); > >> + ret += nr_mlocked; > >> mod_zone_page_state(zone, NR_ISOLATED_FILE, -ret); > >> return ret; > >> } > >> @@ -1523,6 +1528,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, > >> unsigned long nr_unqueued_dirty = 0; > >> unsigned long nr_writeback = 0; > >> unsigned long nr_immediate = 0; > >> + unsigned long nr_mlocked = 0; > >> isolate_mode_t isolate_mode = 0; > >> int file = is_file_lru(lru); > >> struct zone *zone = lruvec_zone(lruvec); > >> @@ -1565,7 +1571,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, > >> > >> nr_reclaimed = shrink_page_list(&page_list, zone, sc, TTU_UNMAP, > >> &nr_dirty, &nr_unqueued_dirty, &nr_congested, > >> - &nr_writeback, &nr_immediate, > >> + &nr_writeback, &nr_immediate, &nr_mlocked, > >> false); > >> > >> spin_lock_irq(&zone->lru_lock); > >> -- > >> 1.9.1 > >> > > -- Kind regards, Minchan Kim -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] vmscan: reclaim_clean_pages_from_list() must count mlocked pages 2015-08-03 15:33 ` Minchan Kim @ 2015-08-03 15:46 ` Jaewon Kim 2015-08-03 23:02 ` Minchan Kim 0 siblings, 1 reply; 6+ messages in thread From: Jaewon Kim @ 2015-08-03 15:46 UTC (permalink / raw) To: Minchan Kim; +Cc: akpm, mgorman, linux-mm, linux-kernel, jaewon31.kim On 2015e?? 08i?? 04i? 1/4 00:33, Minchan Kim wrote: > On Mon, Aug 03, 2015 at 11:55:46PM +0900, Jaewon Kim wrote: >> >> >> On 2015e?? 08i?? 03i? 1/4 21:27, Minchan Kim wrote: >>> Hello, >>> >>> On Mon, Aug 03, 2015 at 07:18:27PM +0900, Jaewon Kim wrote: >>>> reclaim_clean_pages_from_list() decreases NR_ISOLATED_FILE by returned >>>> value from shrink_page_list(). But mlocked pages in the isolated >>>> clean_pages page list would be removed from the list but not counted as >>>> nr_reclaimed. Fix this miscounting by returning the number of mlocked >>>> pages and count it. >>> >>> If there are pages not able to reclaim, VM try to migrate it and >>> have to handle the stat in migrate_pages. >>> If migrate_pages fails again, putback-fiends should handle it. >>> >>> Is there anyting I am missing now? >>> >>> Thanks. >>> >> Hello >> >> Only pages in cc->migratepages will be handled by migrate_pages or >> putback_movable_pages, and NR_ISOLATED_FILE will be counted properly. >> However mlocked pages will not be put back into cc->migratepages, >> and also not be counted in NR_ISOLATED_FILE because putback_lru_page >> in shrink_page_list does not increase NR_ISOLATED_FILE. >> The current reclaim_clean_pages_from_list assumes that shrink_page_list >> returns number of pages removed from the candidate list. >> >> i.e) >> isolate_migratepages_range : NR_ISOLATED_FILE += 10 >> reclaim_clean_pages_from_list : NR_ISOLATED_FILE -= 5 (1 mlocked page) >> migrate_pages : NR_ISOLATED_FILE -=4 >> => NR_ISOLATED_FILE increased by 1 > > Thanks for the clarity. > > I think the problem is shrink_page_list is awkard. It put back to > unevictable pages instantly instead of passing it to caller while > it relies on caller for non-reclaimed-non-unevictable page's putback. > > I think we can make it consistent so that shrink_page_list could > return non-reclaimed pages via page_list and caller can handle it. > As a bonus, it could try to migrate mlocked pages without retrial. > >> >> Thank you. To make clear do you mean changing shrink_page_list like this rather than previous my suggestion? @@ -1157,7 +1157,7 @@ cull_mlocked: if (PageSwapCache(page)) try_to_free_swap(page); unlock_page(page); - putback_lru_page(page); + list_add(&page->lru, &ret_pages); continue; Thank you. >>>> >>>> Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com> >>>> --- >>>> mm/vmscan.c | 10 ++++++++-- >>>> 1 file changed, 8 insertions(+), 2 deletions(-) >>>> >>>> diff --git a/mm/vmscan.c b/mm/vmscan.c >>>> index 5e8eadd..5837695 100644 >>>> --- a/mm/vmscan.c >>>> +++ b/mm/vmscan.c >>>> @@ -849,6 +849,7 @@ static unsigned long shrink_page_list(struct list_head *page_list, >>>> unsigned long *ret_nr_congested, >>>> unsigned long *ret_nr_writeback, >>>> unsigned long *ret_nr_immediate, >>>> + unsigned long *ret_nr_mlocked, >>>> bool force_reclaim) >>>> { >>>> LIST_HEAD(ret_pages); >>>> @@ -1158,6 +1159,7 @@ cull_mlocked: >>>> try_to_free_swap(page); >>>> unlock_page(page); >>>> putback_lru_page(page); >>>> + (*ret_nr_mlocked)++; >>>> continue; >>>> >>>> activate_locked: >>>> @@ -1197,6 +1199,7 @@ unsigned long reclaim_clean_pages_from_list(struct zone *zone, >>>> .may_unmap = 1, >>>> }; >>>> unsigned long ret, dummy1, dummy2, dummy3, dummy4, dummy5; >>>> + unsigned long nr_mlocked = 0; >>>> struct page *page, *next; >>>> LIST_HEAD(clean_pages); >>>> >>>> @@ -1210,8 +1213,10 @@ unsigned long reclaim_clean_pages_from_list(struct zone *zone, >>>> >>>> ret = shrink_page_list(&clean_pages, zone, &sc, >>>> TTU_UNMAP|TTU_IGNORE_ACCESS, >>>> - &dummy1, &dummy2, &dummy3, &dummy4, &dummy5, true); >>>> + &dummy1, &dummy2, &dummy3, &dummy4, &dummy5, >>>> + &nr_mlocked, true); >>>> list_splice(&clean_pages, page_list); >>>> + ret += nr_mlocked; >>>> mod_zone_page_state(zone, NR_ISOLATED_FILE, -ret); >>>> return ret; >>>> } >>>> @@ -1523,6 +1528,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, >>>> unsigned long nr_unqueued_dirty = 0; >>>> unsigned long nr_writeback = 0; >>>> unsigned long nr_immediate = 0; >>>> + unsigned long nr_mlocked = 0; >>>> isolate_mode_t isolate_mode = 0; >>>> int file = is_file_lru(lru); >>>> struct zone *zone = lruvec_zone(lruvec); >>>> @@ -1565,7 +1571,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, >>>> >>>> nr_reclaimed = shrink_page_list(&page_list, zone, sc, TTU_UNMAP, >>>> &nr_dirty, &nr_unqueued_dirty, &nr_congested, >>>> - &nr_writeback, &nr_immediate, >>>> + &nr_writeback, &nr_immediate, &nr_mlocked, >>>> false); >>>> >>>> spin_lock_irq(&zone->lru_lock); >>>> -- >>>> 1.9.1 >>>> >>> > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] vmscan: reclaim_clean_pages_from_list() must count mlocked pages 2015-08-03 15:46 ` Jaewon Kim @ 2015-08-03 23:02 ` Minchan Kim 0 siblings, 0 replies; 6+ messages in thread From: Minchan Kim @ 2015-08-03 23:02 UTC (permalink / raw) To: Jaewon Kim; +Cc: akpm, mgorman, linux-mm, linux-kernel, jaewon31.kim Hello, On Tue, Aug 04, 2015 at 12:46:57AM +0900, Jaewon Kim wrote: > > > On 2015e?? 08i?? 04i? 1/4 00:33, Minchan Kim wrote: > > On Mon, Aug 03, 2015 at 11:55:46PM +0900, Jaewon Kim wrote: > >> > >> > >> On 2015e?? 08i?? 03i? 1/4 21:27, Minchan Kim wrote: > >>> Hello, > >>> > >>> On Mon, Aug 03, 2015 at 07:18:27PM +0900, Jaewon Kim wrote: > >>>> reclaim_clean_pages_from_list() decreases NR_ISOLATED_FILE by returned > >>>> value from shrink_page_list(). But mlocked pages in the isolated > >>>> clean_pages page list would be removed from the list but not counted as > >>>> nr_reclaimed. Fix this miscounting by returning the number of mlocked > >>>> pages and count it. > >>> > >>> If there are pages not able to reclaim, VM try to migrate it and > >>> have to handle the stat in migrate_pages. > >>> If migrate_pages fails again, putback-fiends should handle it. > >>> > >>> Is there anyting I am missing now? > >>> > >>> Thanks. > >>> > >> Hello > >> > >> Only pages in cc->migratepages will be handled by migrate_pages or > >> putback_movable_pages, and NR_ISOLATED_FILE will be counted properly. > >> However mlocked pages will not be put back into cc->migratepages, > >> and also not be counted in NR_ISOLATED_FILE because putback_lru_page > >> in shrink_page_list does not increase NR_ISOLATED_FILE. > >> The current reclaim_clean_pages_from_list assumes that shrink_page_list > >> returns number of pages removed from the candidate list. > >> > >> i.e) > >> isolate_migratepages_range : NR_ISOLATED_FILE += 10 > >> reclaim_clean_pages_from_list : NR_ISOLATED_FILE -= 5 (1 mlocked page) > >> migrate_pages : NR_ISOLATED_FILE -=4 > >> => NR_ISOLATED_FILE increased by 1 > > > > Thanks for the clarity. > > > > I think the problem is shrink_page_list is awkard. It put back to > > unevictable pages instantly instead of passing it to caller while > > it relies on caller for non-reclaimed-non-unevictable page's putback. > > > > I think we can make it consistent so that shrink_page_list could > > return non-reclaimed pages via page_list and caller can handle it. > > As a bonus, it could try to migrate mlocked pages without retrial. > > > >> > >> Thank you. > > To make clear do you mean changing shrink_page_list like this rather than > previous my suggestion? > > @@ -1157,7 +1157,7 @@ cull_mlocked: > if (PageSwapCache(page)) > try_to_free_swap(page); > unlock_page(page); > - putback_lru_page(page); > + list_add(&page->lru, &ret_pages); > continue; Yes. That's what I said. Thanks. -- Kind regards, Minchan Kim -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a> ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2015-08-03 23:03 UTC | newest] Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2015-08-03 10:18 [PATCH] vmscan: reclaim_clean_pages_from_list() must count mlocked pages Jaewon Kim 2015-08-03 12:27 ` Minchan Kim 2015-08-03 14:55 ` Jaewon Kim 2015-08-03 15:33 ` Minchan Kim 2015-08-03 15:46 ` Jaewon Kim 2015-08-03 23:02 ` Minchan Kim
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