diff options
Diffstat (limited to 'mm/vmscan.c')
| -rw-r--r-- | mm/vmscan.c | 60 |
1 files changed, 43 insertions, 17 deletions
diff --git a/mm/vmscan.c b/mm/vmscan.c index e61445dce04e..2d978b28a410 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -175,7 +175,7 @@ static bool sane_reclaim(struct scan_control *sc) if (!memcg) return true; #ifdef CONFIG_CGROUP_WRITEBACK - if (cgroup_on_dfl(mem_cgroup_css(memcg)->cgroup)) + if (memcg->css.cgroup) return true; #endif return false; @@ -973,23 +973,19 @@ static unsigned long shrink_page_list(struct list_head *page_list, * caller can stall after page list has been processed. * * 2) Global or new memcg reclaim encounters a page that is - * not marked for immediate reclaim or the caller does not - * have __GFP_IO. In this case mark the page for immediate + * not marked for immediate reclaim, or the caller does not + * have __GFP_FS (or __GFP_IO if it's simply going to swap, + * not to fs). In this case mark the page for immediate * reclaim and continue scanning. * - * __GFP_IO is checked because a loop driver thread might + * Require may_enter_fs because we would wait on fs, which + * may not have submitted IO yet. And the loop driver might * enter reclaim, and deadlock if it waits on a page for * which it is needed to do the write (loop masks off * __GFP_IO|__GFP_FS for this reason); but more thought * would probably show more reasons. * - * Don't require __GFP_FS, since we're not going into the - * FS, just waiting on its writeback completion. Worryingly, - * ext4 gfs2 and xfs allocate pages with - * grab_cache_page_write_begin(,,AOP_FLAG_NOFS), so testing - * may_enter_fs here is liable to OOM on them. - * - * 3) Legacy memcg encounters a page that is not already marked + * 3) Legacy memcg encounters a page that is already marked * PageReclaim. memcg does not have any dirty pages * throttling so we could easily OOM just because too many * pages are in writeback and there is nothing else to @@ -1005,7 +1001,7 @@ static unsigned long shrink_page_list(struct list_head *page_list, /* Case 2 above */ } else if (sane_reclaim(sc) || - !PageReclaim(page) || !(sc->gfp_mask & __GFP_IO)) { + !PageReclaim(page) || !may_enter_fs) { /* * This is slightly racy - end_page_writeback() * might have just cleared PageReclaim, then @@ -1019,12 +1015,15 @@ static unsigned long shrink_page_list(struct list_head *page_list, */ SetPageReclaim(page); nr_writeback++; - goto keep_locked; /* Case 3 above */ } else { + unlock_page(page); wait_on_page_writeback(page); + /* then go back and try same page again */ + list_add_tail(&page->lru, page_list); + continue; } } @@ -1061,7 +1060,8 @@ static unsigned long shrink_page_list(struct list_head *page_list, * processes. Try to unmap it here. */ if (page_mapped(page) && mapping) { - switch (try_to_unmap(page, ttu_flags)) { + switch (try_to_unmap(page, + ttu_flags|TTU_BATCH_FLUSH)) { case SWAP_FAIL: goto activate_locked; case SWAP_AGAIN: @@ -1101,7 +1101,12 @@ static unsigned long shrink_page_list(struct list_head *page_list, if (!sc->may_writepage) goto keep_locked; - /* Page is dirty, try to write it out here */ + /* + * Page is dirty. Flush the TLB if a writable entry + * potentially exists to avoid CPU writes after IO + * starts and then write it out here. + */ + try_to_unmap_flush_dirty(); switch (pageout(page, mapping, sc)) { case PAGE_KEEP: goto keep_locked; @@ -1194,7 +1199,7 @@ cull_mlocked: if (PageSwapCache(page)) try_to_free_swap(page); unlock_page(page); - putback_lru_page(page); + list_add(&page->lru, &ret_pages); continue; activate_locked: @@ -1212,6 +1217,7 @@ keep: } mem_cgroup_uncharge_list(&free_pages); + try_to_unmap_flush(); free_hot_cold_page_list(&free_pages, true); list_splice(&ret_pages, page_list); @@ -1356,7 +1362,8 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan, unsigned long nr_taken = 0; unsigned long scan; - for (scan = 0; scan < nr_to_scan && !list_empty(src); scan++) { + for (scan = 0; scan < nr_to_scan && nr_taken < nr_to_scan && + !list_empty(src); scan++) { struct page *page; int nr_pages; @@ -2155,6 +2162,23 @@ out: } } +#ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH +static void init_tlb_ubc(void) +{ + /* + * This deliberately does not clear the cpumask as it's expensive + * and unnecessary. If there happens to be data in there then the + * first SWAP_CLUSTER_MAX pages will send an unnecessary IPI and + * then will be cleared. + */ + current->tlb_ubc.flush_required = false; +} +#else +static inline void init_tlb_ubc(void) +{ +} +#endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */ + /* * This is a basic per-zone page freer. Used by both kswapd and direct reclaim. */ @@ -2189,6 +2213,8 @@ static void shrink_lruvec(struct lruvec *lruvec, int swappiness, scan_adjusted = (global_reclaim(sc) && !current_is_kswapd() && sc->priority == DEF_PRIORITY); + init_tlb_ubc(); + blk_start_plug(&plug); while (nr[LRU_INACTIVE_ANON] || nr[LRU_ACTIVE_FILE] || nr[LRU_INACTIVE_FILE]) { |