From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759080Ab3K1HsI (ORCPT ); Thu, 28 Nov 2013 02:48:08 -0500 Received: from LGEMRELSE1Q.lge.com ([156.147.1.111]:44430 "EHLO LGEMRELSE1Q.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758921Ab3K1Hqn (ORCPT ); Thu, 28 Nov 2013 02:46:43 -0500 X-AuditID: 9c93016f-b7b6aae000005fae-d6-5296f4df5c40 From: Joonsoo Kim To: Andrew Morton Cc: Mel Gorman , Hugh Dickins , Rik van Riel , Ingo Molnar , Naoya Horiguchi , Hillf Danton , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Joonsoo Kim , Joonsoo Kim Subject: [PATCH 5/9] mm/rmap: extend rmap_walk_xxx() to cope with different cases Date: Thu, 28 Nov 2013 16:48:42 +0900 Message-Id: <1385624926-28883-6-git-send-email-iamjoonsoo.kim@lge.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1385624926-28883-1-git-send-email-iamjoonsoo.kim@lge.com> References: <1385624926-28883-1-git-send-email-iamjoonsoo.kim@lge.com> X-Brightmail-Tracker: AAAAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There are a lot of common parts in traversing functions, but there are also a little of uncommon parts in it. By assigning proper function pointer on each rmap_walker_control, we can handle these difference correctly. Following are differences we should handle. 1. difference of lock function in anon mapping case 2. nonlinear handling in file mapping case 3. prechecked condition: checking memcg in page_referenced(), checking VM_SHARE in page_mkclean() checking temporary vma in try_to_unmap() 4. exit condition: checking page_mapped() in try_to_unmap() So, in this patch, I introduce 4 function pointers to handle above differences. Signed-off-by: Joonsoo Kim diff --git a/include/linux/rmap.h b/include/linux/rmap.h index 0f65686..58624b4 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -239,6 +239,12 @@ struct rmap_walk_control { int (*main)(struct page *, struct vm_area_struct *, unsigned long, void *); void *arg; /* argument to main function */ + int (*main_done)(struct page *page); /* check exit condition */ + int (*file_nonlinear)(struct page *, struct address_space *, + struct vm_area_struct *vma); + struct anon_vma *(*anon_lock)(struct page *); + int (*vma_skip)(struct vm_area_struct *, void *); + void *skip_arg; /* argument to vma_skip function */ }; /* diff --git a/mm/ksm.c b/mm/ksm.c index c42ec30..0aa6e09 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -2032,12 +2032,19 @@ again: if ((rmap_item->mm == vma->vm_mm) == search_new_forks) continue; + if (rwc->vma_skip && rwc->vma_skip(vma, rwc->skip_arg)) + continue; + ret = rwc->main(page, vma, rmap_item->address, rwc->arg); if (ret != SWAP_AGAIN) { anon_vma_unlock_read(anon_vma); goto out; } + if (rwc->main_done && rwc->main_done(page)) { + anon_vma_unlock_read(anon_vma); + goto out; + } } anon_vma_unlock_read(anon_vma); } diff --git a/mm/rmap.c b/mm/rmap.c index 5933488..5dad5dd 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1683,10 +1683,14 @@ void __put_anon_vma(struct anon_vma *anon_vma) } #ifdef CONFIG_MIGRATION -static struct anon_vma *rmap_walk_anon_lock(struct page *page) +static struct anon_vma *rmap_walk_anon_lock(struct page *page, + struct rmap_walk_control *rwc) { struct anon_vma *anon_vma; + if (rwc->anon_lock) + return rwc->anon_lock(page); + /* * Note: remove_migration_ptes() cannot use page_lock_anon_vma_read() * because that depends on page_mapped(); but not all its usages @@ -1712,16 +1716,22 @@ static int rmap_walk_anon(struct page *page, struct rmap_walk_control *rwc) struct anon_vma_chain *avc; int ret = SWAP_AGAIN; - anon_vma = rmap_walk_anon_lock(page); + anon_vma = rmap_walk_anon_lock(page, rwc); if (!anon_vma) return ret; anon_vma_interval_tree_foreach(avc, &anon_vma->rb_root, pgoff, pgoff) { struct vm_area_struct *vma = avc->vma; unsigned long address = vma_address(page, vma); + + if (rwc->vma_skip && rwc->vma_skip(vma, rwc->skip_arg)) + continue; + ret = rwc->main(page, vma, address, rwc->arg); if (ret != SWAP_AGAIN) break; + if (rwc->main_done && rwc->main_done(page)) + break; } anon_vma_unlock_read(anon_vma); return ret; @@ -1743,15 +1753,26 @@ static int rmap_walk_file(struct page *page, struct rmap_walk_control *rwc) mutex_lock(&mapping->i_mmap_mutex); vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) { unsigned long address = vma_address(page, vma); + + if (rwc->vma_skip && rwc->vma_skip(vma, rwc->skip_arg)) + continue; + ret = rwc->main(page, vma, address, rwc->arg); if (ret != SWAP_AGAIN) - break; + goto done; + if (rwc->main_done && rwc->main_done(page)) + goto done; } - /* - * No nonlinear handling: being always shared, nonlinear vmas - * never contain migration ptes. Decide what to do about this - * limitation to linear when we need rmap_walk() on nonlinear. - */ + + if (!rwc->file_nonlinear) + goto done; + + if (list_empty(&mapping->i_mmap_nonlinear)) + goto done; + + ret = rwc->file_nonlinear(page, mapping, vma); + +done: mutex_unlock(&mapping->i_mmap_mutex); return ret; } -- 1.7.9.5