From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx128.postini.com [74.125.245.128]) by kanga.kvack.org (Postfix) with SMTP id 0F0516B0038 for ; Sat, 3 Aug 2013 22:14:31 -0400 (EDT) From: "Kirill A. Shutemov" Subject: [PATCH 13/23] thp, mm: allocate huge pages in grab_cache_page_write_begin() Date: Sun, 4 Aug 2013 05:17:15 +0300 Message-Id: <1375582645-29274-14-git-send-email-kirill.shutemov@linux.intel.com> In-Reply-To: <1375582645-29274-1-git-send-email-kirill.shutemov@linux.intel.com> References: <1375582645-29274-1-git-send-email-kirill.shutemov@linux.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: Andrea Arcangeli , Andrew Morton Cc: Al Viro , Hugh Dickins , Wu Fengguang , Jan Kara , Mel Gorman , linux-mm@kvack.org, Andi Kleen , Matthew Wilcox , "Kirill A. Shutemov" , Hillf Danton , Dave Hansen , Ning Qu , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" From: "Kirill A. Shutemov" Try to allocate huge page if flags has AOP_FLAG_TRANSHUGE. If, for some reason, it's not possible allocate a huge page at this possition, it returns NULL. Caller should take care of fallback to small pages. Signed-off-by: Kirill A. Shutemov --- include/linux/fs.h | 1 + mm/filemap.c | 24 ++++++++++++++++++++++-- 2 files changed, 23 insertions(+), 2 deletions(-) diff --git a/include/linux/fs.h b/include/linux/fs.h index b09ddc0..d5f58b3 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -282,6 +282,7 @@ enum positive_aop_returns { #define AOP_FLAG_NOFS 0x0004 /* used by filesystem to direct * helper code (eg buffer layer) * to clear GFP_FS from alloc */ +#define AOP_FLAG_TRANSHUGE 0x0008 /* allocate transhuge page */ /* * oh the beauties of C type declarations. diff --git a/mm/filemap.c b/mm/filemap.c index 28f4927..b17ebb9 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2313,18 +2313,38 @@ struct page *grab_cache_page_write_begin(struct address_space *mapping, gfp_t gfp_mask; struct page *page; gfp_t gfp_notmask = 0; + bool must_use_thp = (flags & AOP_FLAG_TRANSHUGE) && + IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE_PAGECACHE); + gfp_mask = mapping_gfp_mask(mapping); + if (must_use_thp) { + BUG_ON(index & HPAGE_CACHE_INDEX_MASK); + BUG_ON(!(gfp_mask & __GFP_COMP)); + } if (mapping_cap_account_dirty(mapping)) gfp_mask |= __GFP_WRITE; if (flags & AOP_FLAG_NOFS) gfp_notmask = __GFP_FS; repeat: page = find_lock_page(mapping, index); - if (page) + if (page) { + if (must_use_thp && !PageTransHuge(page)) { + unlock_page(page); + page_cache_release(page); + return NULL; + } goto found; + } - page = __page_cache_alloc(gfp_mask & ~gfp_notmask); + if (must_use_thp) { + page = alloc_pages(gfp_mask & ~gfp_notmask, HPAGE_PMD_ORDER); + if (page) + count_vm_event(THP_WRITE_ALLOC); + else + count_vm_event(THP_WRITE_ALLOC_FAILED); + } else + page = __page_cache_alloc(gfp_mask & ~gfp_notmask); if (!page) return NULL; status = add_to_page_cache_lru(page, mapping, index, -- 1.8.3.2 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org