From: Zi Yan <ziy@xxxxxxxxxx> This change adds a new migration mode called MIGRATE_MT to enable multi threaded page copy implementation inside copy_huge_page() function by selectively calling copy_pages_mthread() when requested. But it still falls back using the regular page copy mechanism instead the previous multi threaded attempt fails. It also attempts multi threaded copy for regular pages. Signed-off-by: Zi Yan <zi.yan@xxxxxxxxxxxxxx> Signed-off-by: Anshuman Khandual <khandual@xxxxxxxxxxxxxxxxxx> --- include/linux/migrate_mode.h | 1 + mm/migrate.c | 25 ++++++++++++++++++------- 2 files changed, 19 insertions(+), 7 deletions(-) diff --git a/include/linux/migrate_mode.h b/include/linux/migrate_mode.h index 89c170060e5b..d344ad60f499 100644 --- a/include/linux/migrate_mode.h +++ b/include/linux/migrate_mode.h @@ -12,6 +12,7 @@ enum migrate_mode { MIGRATE_SYNC_LIGHT = 1<<1, MIGRATE_SYNC = 1<<2, MIGRATE_ST = 1<<3, + MIGRATE_MT = 1<<4, }; #endif /* MIGRATE_MODE_H_INCLUDED */ diff --git a/mm/migrate.c b/mm/migrate.c index 87253cb9b50a..21307219428d 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -601,6 +601,7 @@ static void copy_huge_page(struct page *dst, struct page *src, { int i; int nr_pages; + int rc = -EFAULT; if (PageHuge(src)) { /* hugetlbfs page */ @@ -617,10 +618,14 @@ static void copy_huge_page(struct page *dst, struct page *src, nr_pages = hpage_nr_pages(src); } - for (i = 0; i < nr_pages; i++) { - cond_resched(); - copy_highpage(dst + i, src + i); - } + if (mode & MIGRATE_MT) + rc = copy_pages_mthread(dst, src, nr_pages); + + if (rc) + for (i = 0; i < nr_pages; i++) { + cond_resched(); + copy_highpage(dst + i, src + i); + } } /* @@ -631,10 +636,16 @@ void migrate_page_copy(struct page *newpage, struct page *page, { int cpupid; - if (PageHuge(page) || PageTransHuge(page)) + if (PageHuge(page) || PageTransHuge(page)) { copy_huge_page(newpage, page, mode); - else - copy_highpage(newpage, page); + } else { + if (mode & MIGRATE_MT) { + if (copy_pages_mthread(newpage, page, 1)) + copy_highpage(newpage, page); + } else { + copy_highpage(newpage, page); + } + } if (PageError(page)) SetPageError(newpage); -- 2.11.0 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>