From 7cbe34cf86c673503b177ff47cfa2c7030dabb50 Mon Sep 17 00:00:00 2001 From: Christoph Lameter Date: Sun, 8 Jan 2006 01:00:49 -0800 Subject: [PATCH] [PATCH] Swap Migration V5: Add CONFIG_MIGRATION for page migration support Include page migration if the system is NUMA or having a memory model that allows distinct areas of memory (SPARSEMEM, DISCONTIGMEM). And: - Only include lru_add_drain_per_cpu if building for an SMP system. Signed-off-by: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/swap.h | 2 ++ mm/Kconfig | 7 +++++++ mm/vmscan.c | 20 +++++++++++--------- 3 files changed, 20 insertions(+), 9 deletions(-) diff --git a/include/linux/swap.h b/include/linux/swap.h index 893096e..117add0 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -178,7 +178,9 @@ extern int vm_swappiness; extern int isolate_lru_page(struct page *p); extern int putback_lru_pages(struct list_head *l); +#ifdef CONFIG_MIGRATION extern int migrate_pages(struct list_head *l, struct list_head *t); +#endif #ifdef CONFIG_MMU /* linux/mm/shmem.c */ diff --git a/mm/Kconfig b/mm/Kconfig index b3db11f..a9cb80a 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -132,3 +132,10 @@ config SPLIT_PTLOCK_CPUS default "4096" if ARM && !CPU_CACHE_VIPT default "4096" if PARISC && !PA20 default "4" + +# +# support for page migration +# +config MIGRATION + def_bool y if NUMA || SPARSEMEM || DISCONTIGMEM + depends on SWAP diff --git a/mm/vmscan.c b/mm/vmscan.c index a537a7f..58270ae 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -568,6 +568,7 @@ keep: return reclaimed; } +#ifdef CONFIG_MIGRATION /* * swapout a single page * page is locked upon entry, unlocked on exit @@ -656,8 +657,9 @@ redo: /* * Skip locked pages during the first two passes to give the - * functions holding the lock time to release the page. Later we use - * lock_page to have a higher chance of acquiring the lock. + * functions holding the lock time to release the page. Later we + * use lock_page() to have a higher chance of acquiring the + * lock. */ if (pass > 2) lock_page(page); @@ -669,15 +671,15 @@ redo: * Only wait on writeback if we have already done a pass where * we we may have triggered writeouts for lots of pages. */ - if (pass > 0) + if (pass > 0) { wait_on_page_writeback(page); - else + } else { if (PageWriteback(page)) { unlock_page(page); goto retry_later; } + } -#ifdef CONFIG_SWAP if (PageAnon(page) && !PageSwapCache(page)) { if (!add_to_swap(page)) { unlock_page(page); @@ -686,16 +688,15 @@ redo: continue; } } -#endif /* CONFIG_SWAP */ /* * Page is properly locked and writeback is complete. * Try to migrate the page. */ - if (swap_page(page)) { + if (!swap_page(page)) + continue; retry_later: - retry++; - } + retry++; } if (retry && pass++ < 10) goto redo; @@ -708,6 +709,7 @@ retry_later: return nr_failed + retry; } +#endif /* * zone->lru_lock is heavily contended. Some of the functions that -- 2.7.4