The patch titled Subject: mm: rmap: split out page_remove_file_rmap() has been added to the -mm tree. Its filename is mm-rmap-split-out-page_remove_file_rmap.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-rmap-split-out-page_remove_file_rmap.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-rmap-split-out-page_remove_file_rmap.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Johannes Weiner <hannes@xxxxxxxxxxx> Subject: mm: rmap: split out page_remove_file_rmap() page_remove_rmap() has too many branches on PageAnon() and is hard to follow. Move the file part into a separate function. Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx> Reviewed-by: Michal Hocko <mhocko@xxxxxxx> Cc: Vladimir Davydov <vdavydov@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/rmap.c | 78 ++++++++++++++++++++++++++++++---------------------- 1 file changed, 46 insertions(+), 32 deletions(-) diff -puN mm/rmap.c~mm-rmap-split-out-page_remove_file_rmap mm/rmap.c --- a/mm/rmap.c~mm-rmap-split-out-page_remove_file_rmap +++ a/mm/rmap.c @@ -1054,6 +1054,36 @@ void page_add_file_rmap(struct page *pag mem_cgroup_end_page_stat(memcg, locked, flags); } +static void page_remove_file_rmap(struct page *page) +{ + struct mem_cgroup *memcg; + unsigned long flags; + bool locked; + + memcg = mem_cgroup_begin_page_stat(page, &locked, &flags); + + /* page still mapped by someone else? */ + if (!atomic_add_negative(-1, &page->_mapcount)) + goto out; + + /* Hugepages are not counted in NR_FILE_MAPPED for now. */ + if (unlikely(PageHuge(page))) + goto out; + + /* + * We use the irq-unsafe __{inc|mod}_zone_page_stat because + * these counters are not modified in interrupt context, and + * pte lock(a spinlock) is held, which implies preemption disabled. + */ + __dec_zone_page_state(page, NR_FILE_MAPPED); + mem_cgroup_dec_page_stat(memcg, MEM_CGROUP_STAT_FILE_MAPPED); + + if (unlikely(PageMlocked(page))) + clear_page_mlock(page); +out: + mem_cgroup_end_page_stat(memcg, locked, flags); +} + /** * page_remove_rmap - take down pte mapping from a page * @page: page to remove mapping from @@ -1062,46 +1092,33 @@ void page_add_file_rmap(struct page *pag */ void page_remove_rmap(struct page *page) { - struct mem_cgroup *uninitialized_var(memcg); - bool anon = PageAnon(page); - unsigned long flags; - bool locked; - - /* - * The anon case has no mem_cgroup page_stat to update; but may - * uncharge_page() below, where the lock ordering can deadlock if - * we hold the lock against page_stat move: so avoid it on anon. - */ - if (!anon) - memcg = mem_cgroup_begin_page_stat(page, &locked, &flags); + if (!PageAnon(page)) { + page_remove_file_rmap(page); + return; + } /* page still mapped by someone else? */ if (!atomic_add_negative(-1, &page->_mapcount)) - goto out; + return; + + /* Hugepages are not counted in NR_ANON_PAGES for now. */ + if (unlikely(PageHuge(page))) + return; /* - * Hugepages are not counted in NR_ANON_PAGES nor NR_FILE_MAPPED - * and not charged by memcg for now. - * * We use the irq-unsafe __{inc|mod}_zone_page_stat because * these counters are not modified in interrupt context, and - * these counters are not modified in interrupt context, and * pte lock(a spinlock) is held, which implies preemption disabled. */ - if (unlikely(PageHuge(page))) - goto out; - if (anon) { - if (PageTransHuge(page)) - __dec_zone_page_state(page, - NR_ANON_TRANSPARENT_HUGEPAGES); - __mod_zone_page_state(page_zone(page), NR_ANON_PAGES, - -hpage_nr_pages(page)); - } else { - __dec_zone_page_state(page, NR_FILE_MAPPED); - mem_cgroup_dec_page_stat(memcg, MEM_CGROUP_STAT_FILE_MAPPED); - } + if (PageTransHuge(page)) + __dec_zone_page_state(page, NR_ANON_TRANSPARENT_HUGEPAGES); + + __mod_zone_page_state(page_zone(page), NR_ANON_PAGES, + -hpage_nr_pages(page)); + if (unlikely(PageMlocked(page))) clear_page_mlock(page); + /* * It would be tidy to reset the PageAnon mapping here, * but that might overwrite a racing page_add_anon_rmap @@ -1111,9 +1128,6 @@ void page_remove_rmap(struct page *page) * Leaving it set also helps swapoff to reinstate ptes * faster for those pages still in swapcache. */ -out: - if (!anon) - mem_cgroup_end_page_stat(memcg, locked, flags); } /* _ Patches currently in -mm which might be from hannes@xxxxxxxxxxx are cgroup-kmemleak-add-kmemleak_free-for-cgroup-deallocations.patch mm-page-writeback-inline-account_page_dirtied-into-single-caller.patch mm-memcontrol-fix-missed-end-writeback-page-accounting.patch mm-memcontrol-fix-missed-end-writeback-page-accounting-fix.patch mm-rmap-split-out-page_remove_file_rmap.patch mm-memcontrol-lockless-page-counters.patch mm-memcontrol-lockless-page-counters-fix.patch mm-memcontrol-lockless-page-counters-fix-fix.patch mm-memcontrol-lockless-page-counters-fix-2.patch mm-hugetlb_cgroup-convert-to-lockless-page-counters.patch kernel-res_counter-remove-the-unused-api.patch kernel-res_counter-remove-the-unused-api-fix.patch kernel-res_counter-remove-the-unused-api-fix-2.patch mm-memcontrol-convert-reclaim-iterator-to-simple-css-refcounting.patch mm-memcontrol-convert-reclaim-iterator-to-simple-css-refcounting-fix.patch mm-memcontrol-take-a-css-reference-for-each-charged-page.patch mm-memcontrol-remove-obsolete-kmemcg-pinning-tricks.patch mm-memcontrol-continue-cache-reclaim-from-offlined-groups.patch mm-memcontrol-remove-synchroneous-stock-draining-code.patch mm-vmscan-count-only-dirty-pages-as-congested.patch memcg-simplify-unreclaimable-groups-handling-in-soft-limit-reclaim.patch mm-memcontrol-update-mem_cgroup_page_lruvec-documentation.patch mm-memcontrol-clarify-migration-where-old-page-is-uncharged.patch memcg-remove-activate_kmem_mutex.patch mm-memcontrol-micro-optimize-mem_cgroup_split_huge_fixup.patch mm-memcontrol-uncharge-pages-on-swapout.patch mm-memcontrol-uncharge-pages-on-swapout-fix.patch mm-memcontrol-remove-unnecessary-pcg_memsw-memoryswap-charge-flag.patch mm-memcontrol-remove-unnecessary-pcg_mem-memory-charge-flag.patch mm-memcontrol-remove-unnecessary-pcg_used-pc-mem_cgroup-valid-flag.patch mm-memcontrol-remove-unnecessary-pcg_used-pc-mem_cgroup-valid-flag-fix.patch mm-memcontrol-inline-memcg-move_lock-locking.patch mm-memcontrol-dont-pass-a-null-memcg-to-mem_cgroup_end_move.patch mm-memcontrol-fold-mem_cgroup_start_move-mem_cgroup_end_move.patch debugging-keep-track-of-page-owners.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html