From 189ebff2894a9d0f4e250dd1e154d282ef0a6779 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Tue, 31 Jul 2012 16:42:06 -0700 Subject: hugetlb: simplify migrate_huge_page() Since we migrate only one hugepage, don't use linked list for passing the page around. Directly pass the page that need to be migrated as argument. This also removes the usage of page->lru in the migrate path. Signed-off-by: Aneesh Kumar K.V Reviewed-by: KAMEZAWA Hiroyuki Cc: David Rientjes Cc: Hillf Danton Reviewed-by: Michal Hocko Cc: KOSAKI Motohiro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/migrate.c | 65 ++++++++++++++++++++---------------------------------------- 1 file changed, 21 insertions(+), 44 deletions(-) (limited to 'mm/migrate.c') diff --git a/mm/migrate.c b/mm/migrate.c index be26d5cbe56b..fdce3a29fc4c 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -932,15 +932,8 @@ static int unmap_and_move_huge_page(new_page_t get_new_page, if (anon_vma) put_anon_vma(anon_vma); unlock_page(hpage); - out: - if (rc != -EAGAIN) { - list_del(&hpage->lru); - put_page(hpage); - } - put_page(new_hpage); - if (result) { if (rc) *result = rc; @@ -1016,48 +1009,32 @@ out: return nr_failed + retry; } -int migrate_huge_pages(struct list_head *from, - new_page_t get_new_page, unsigned long private, bool offlining, - enum migrate_mode mode) +int migrate_huge_page(struct page *hpage, new_page_t get_new_page, + unsigned long private, bool offlining, + enum migrate_mode mode) { - int retry = 1; - int nr_failed = 0; - int pass = 0; - struct page *page; - struct page *page2; - int rc; - - for (pass = 0; pass < 10 && retry; pass++) { - retry = 0; - - list_for_each_entry_safe(page, page2, from, lru) { + int pass, rc; + + for (pass = 0; pass < 10; pass++) { + rc = unmap_and_move_huge_page(get_new_page, + private, hpage, pass > 2, offlining, + mode); + switch (rc) { + case -ENOMEM: + goto out; + case -EAGAIN: + /* try again */ cond_resched(); - - rc = unmap_and_move_huge_page(get_new_page, - private, page, pass > 2, offlining, - mode); - - switch(rc) { - case -ENOMEM: - goto out; - case -EAGAIN: - retry++; - break; - case 0: - break; - default: - /* Permanent failure */ - nr_failed++; - break; - } + break; + case 0: + goto out; + default: + rc = -EIO; + goto out; } } - rc = 0; out: - if (rc) - return rc; - - return nr_failed + retry; + return rc; } #ifdef CONFIG_NUMA -- cgit v1.2.3 From 8e6ac7fab374816de9a8b0a8fbb02ef761a30ff4 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Tue, 31 Jul 2012 16:42:27 -0700 Subject: hugetlb/cgroup: migrate hugetlb cgroup info from oldpage to new page during migration With HugeTLB pages, hugetlb cgroup is uncharged in compound page destructor. Since we are holding a hugepage reference, we can be sure that old page won't get uncharged till the last put_page(). Signed-off-by: Aneesh Kumar K.V Cc: David Rientjes Acked-by: KAMEZAWA Hiroyuki Cc: Hillf Danton Cc: Michal Hocko Cc: KOSAKI Motohiro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/migrate.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'mm/migrate.c') diff --git a/mm/migrate.c b/mm/migrate.c index fdce3a29fc4c..6c37c51565e5 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -33,6 +33,7 @@ #include #include #include +#include #include #include @@ -931,6 +932,10 @@ static int unmap_and_move_huge_page(new_page_t get_new_page, if (anon_vma) put_anon_vma(anon_vma); + + if (!rc) + hugetlb_cgroup_migrate(hpage, new_hpage); + unlock_page(hpage); out: put_page(new_hpage); -- cgit v1.2.3 From 0030f535a5cf9b1841d2088c10a0b2f8f2987460 Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Tue, 31 Jul 2012 16:45:25 -0700 Subject: mm: memcg: fix compaction/migration failing due to memcg limits Compaction (and page migration in general) can currently be hindered through pages being owned by memory cgroups that are at their limits and unreclaimable. The reason is that the replacement page is being charged against the limit while the page being replaced is also still charged. But this seems unnecessary, given that only one of the two pages will still be in use after migration finishes. This patch changes the memcg migration sequence so that the replacement page is not charged. Whatever page is still in use after successful or failed migration gets to keep the charge of the page that was going to be replaced. The replacement page will still show up temporarily in the rss/cache statistics, this can be fixed in a later patch as it's less urgent. Reported-by: David Rientjes Signed-off-by: Johannes Weiner Acked-by: KAMEZAWA Hiroyuki Acked-by: Michal Hocko Cc: Hugh Dickins Cc: David Rientjes Cc: Wanpeng Li Cc: Mel Gorman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/migrate.c | 11 ++--------- 1 file changed, 2 insertions(+), 9 deletions(-) (limited to 'mm/migrate.c') diff --git a/mm/migrate.c b/mm/migrate.c index 6c37c51565e5..77ed2d773705 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -683,7 +683,6 @@ static int __unmap_and_move(struct page *page, struct page *newpage, { int rc = -EAGAIN; int remap_swapcache = 1; - int charge = 0; struct mem_cgroup *mem; struct anon_vma *anon_vma = NULL; @@ -725,12 +724,7 @@ static int __unmap_and_move(struct page *page, struct page *newpage, } /* charge against new page */ - charge = mem_cgroup_prepare_migration(page, newpage, &mem, GFP_KERNEL); - if (charge == -ENOMEM) { - rc = -ENOMEM; - goto unlock; - } - BUG_ON(charge); + mem_cgroup_prepare_migration(page, newpage, &mem); if (PageWriteback(page)) { /* @@ -820,8 +814,7 @@ skip_unmap: put_anon_vma(anon_vma); uncharge: - if (!charge) - mem_cgroup_end_migration(mem, page, newpage, rc == 0); + mem_cgroup_end_migration(mem, page, newpage, rc == 0); unlock: unlock_page(page); out: -- cgit v1.2.3