Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757925AbZKDTSO (ORCPT ); Wed, 4 Nov 2009 14:18:14 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756960AbZKDTSN (ORCPT ); Wed, 4 Nov 2009 14:18:13 -0500 Received: from smtp2.ultrahosting.com ([74.213.174.253]:43791 "EHLO smtp.ultrahosting.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1756909AbZKDTSM (ORCPT ); Wed, 4 Nov 2009 14:18:12 -0500 Date: Wed, 4 Nov 2009 14:17:24 -0500 (EST) From: Christoph Lameter X-X-Sender: cl@V090114053VZO-1 To: KAMEZAWA Hiroyuki cc: "hugh.dickins@tiscali.co.uk" , linux-mm@kvack.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, Tejun Heo Subject: Re: [MM] Remove rss batching from copy_page_range() In-Reply-To: Message-ID: References: User-Agent: Alpine 1.10 (DEB 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3682 Lines: 119 From: Christoph Lameter Subject: Remove rss batching from copy_page_range() With per cpu counters in mm there is no need for batching mm counter updates anymore. Update counters directly while copying pages. Signed-off-by: Christoph Lameter --- mm/memory.c | 27 ++++++++------------------- 1 file changed, 8 insertions(+), 19 deletions(-) Index: linux-2.6/mm/memory.c =================================================================== --- linux-2.6.orig/mm/memory.c 2009-11-04 12:15:03.000000000 -0600 +++ linux-2.6/mm/memory.c 2009-11-04 13:03:45.000000000 -0600 @@ -376,14 +376,6 @@ int __pte_alloc_kernel(pmd_t *pmd, unsig return 0; } -static inline void add_mm_rss(struct mm_struct *mm, int file_rss, int anon_rss) -{ - if (file_rss) - __this_cpu_add(mm->rss->file, file_rss); - if (anon_rss) - __this_cpu_add(mm->rss->anon, anon_rss); -} - /* * This function is called to print an error when a bad pte * is found. For example, we might have a PFN-mapped pte in @@ -575,7 +567,7 @@ out: static inline void copy_one_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm, pte_t *dst_pte, pte_t *src_pte, struct vm_area_struct *vma, - unsigned long addr, int *rss) + unsigned long addr) { unsigned long vm_flags = vma->vm_flags; pte_t pte = *src_pte; @@ -630,7 +622,10 @@ copy_one_pte(struct mm_struct *dst_mm, s if (page) { get_page(page); page_dup_rmap(page); - rss[PageAnon(page)]++; + if (PageAnon(page)) + __this_cpu_inc(dst_mm->rss->anon); + else + __this_cpu_inc(dst_mm->rss->file); } out_set_pte: @@ -645,10 +640,8 @@ static int copy_pte_range(struct mm_stru pte_t *src_pte, *dst_pte; spinlock_t *src_ptl, *dst_ptl; int progress = 0; - int rss[2]; again: - rss[1] = rss[0] = 0; dst_pte = pte_alloc_map_lock(dst_mm, dst_pmd, addr, &dst_ptl); if (!dst_pte) return -ENOMEM; @@ -674,14 +667,13 @@ again: progress++; continue; } - copy_one_pte(dst_mm, src_mm, dst_pte, src_pte, vma, addr, rss); + copy_one_pte(dst_mm, src_mm, dst_pte, src_pte, vma, addr); progress += 8; } while (dst_pte++, src_pte++, addr += PAGE_SIZE, addr != end); arch_leave_lazy_mmu_mode(); spin_unlock(src_ptl); pte_unmap_nested(orig_src_pte); - add_mm_rss(dst_mm, rss[0], rss[1]); pte_unmap_unlock(orig_dst_pte, dst_ptl); cond_resched(); if (addr != end) @@ -803,8 +795,6 @@ static unsigned long zap_pte_range(struc struct mm_struct *mm = tlb->mm; pte_t *pte; spinlock_t *ptl; - int file_rss = 0; - int anon_rss = 0; pte = pte_offset_map_lock(mm, pmd, addr, &ptl); arch_enter_lazy_mmu_mode(); @@ -850,14 +840,14 @@ static unsigned long zap_pte_range(struc set_pte_at(mm, addr, pte, pgoff_to_pte(page->index)); if (PageAnon(page)) - anon_rss--; + __this_cpu_dec(mm->rss->anon); else { if (pte_dirty(ptent)) set_page_dirty(page); if (pte_young(ptent) && likely(!VM_SequentialReadHint(vma))) mark_page_accessed(page); - file_rss--; + __this_cpu_dec(mm->rss->file); } page_remove_rmap(page); if (unlikely(page_mapcount(page) < 0)) @@ -880,7 +870,6 @@ static unsigned long zap_pte_range(struc pte_clear_not_present_full(mm, addr, pte, tlb->fullmm); } while (pte++, addr += PAGE_SIZE, (addr != end && *zap_work > 0)); - add_mm_rss(mm, file_rss, anon_rss); arch_leave_lazy_mmu_mode(); pte_unmap_unlock(pte - 1, ptl); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/