Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933380Ab1C3V4L (ORCPT ); Wed, 30 Mar 2011 17:56:11 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:44764 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933359Ab1C3V4I (ORCPT ); Wed, 30 Mar 2011 17:56:08 -0400 Date: Wed, 30 Mar 2011 14:45:07 -0700 From: Andrew Morton To: KOSAKI Motohiro Cc: Andi Kleen , Andi Kleen , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 8/8] Add VM counters for transparent hugepages Message-Id: <20110330144507.2c0ecf73.akpm@linux-foundation.org> In-Reply-To: <20110308114159.7EAD.A69D9226@jp.fujitsu.com> References: <20110307172609.8A01.A69D9226@jp.fujitsu.com> <20110307163513.GC13384@alboin.amr.corp.intel.com> <20110308114159.7EAD.A69D9226@jp.fujitsu.com> X-Mailer: Sylpheed 3.0.2 (GTK+ 2.20.1; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5986 Lines: 182 On Tue, 8 Mar 2011 11:43:23 +0900 (JST) KOSAKI Motohiro wrote: > > > Don't we need to make per zone stastics? I'm afraid small dma zone > > > makes much thp-splitting and screw up this stastics. > > > > Does it? I haven't seen that so far. > > > > If it happens a lot it would be better to disable THP for the 16MB DMA > > zone at least. Or did you mean the 4GB zone? > > I assumered 4GB. And cpusets/mempolicy binding might makes similar > issue. It can make only one zone high pressure. > > But, hmmm... > Do you mean you don't hit any issue then? I don't think do don't tested > NUMA machine. So, it has no practical problem I can agree this. > I didn't actually merge this patch because I assumed you guys were still arguing over it. But I now see you weren't. Do we still want it? Are we sure we don't want the per-zone numbers? From: Andi Kleen I found it difficult to make sense of transparent huge pages without having any counters for its actions. Add some counters to vmstat for allocation of transparent hugepages and fallback to smaller pages. Optional patch, but useful for development and understanding the system. Contains improvements from Andrea Arcangeli and Johannes Weiner [akpm@linux-foundation.org: coding-style fixes] [hannes@cmpxchg.org: fix vmstat_text[] entries] Signed-off-by: Andi Kleen Acked-by: Andrea Arcangeli Reviewed-by: KAMEZAWA Hiroyuki Signed-off-by: Johannes Weiner Signed-off-by: Andrew Morton --- include/linux/vmstat.h | 7 +++++++ mm/huge_memory.c | 25 +++++++++++++++++++++---- mm/vmstat.c | 9 +++++++++ 3 files changed, 37 insertions(+), 4 deletions(-) diff -puN include/linux/vmstat.h~mm-add-vm-counters-for-transparent-hugepages include/linux/vmstat.h --- a/include/linux/vmstat.h~mm-add-vm-counters-for-transparent-hugepages +++ a/include/linux/vmstat.h @@ -58,6 +58,13 @@ enum vm_event_item { PGPGIN, PGPGOUT, PS UNEVICTABLE_PGCLEARED, /* on COW, page truncate */ UNEVICTABLE_PGSTRANDED, /* unable to isolate on unlock */ UNEVICTABLE_MLOCKFREED, +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + THP_FAULT_ALLOC, + THP_FAULT_FALLBACK, + THP_COLLAPSE_ALLOC, + THP_COLLAPSE_ALLOC_FAILED, + THP_SPLIT, +#endif NR_VM_EVENT_ITEMS }; diff -puN mm/huge_memory.c~mm-add-vm-counters-for-transparent-hugepages mm/huge_memory.c --- a/mm/huge_memory.c~mm-add-vm-counters-for-transparent-hugepages +++ a/mm/huge_memory.c @@ -680,8 +680,11 @@ int do_huge_pmd_anonymous_page(struct mm return VM_FAULT_OOM; page = alloc_hugepage_vma(transparent_hugepage_defrag(vma), vma, haddr, numa_node_id(), 0); - if (unlikely(!page)) + if (unlikely(!page)) { + count_vm_event(THP_FAULT_FALLBACK); goto out; + } + count_vm_event(THP_FAULT_ALLOC); if (unlikely(mem_cgroup_newpage_charge(page, mm, GFP_KERNEL))) { put_page(page); goto out; @@ -909,11 +912,13 @@ int do_huge_pmd_wp_page(struct mm_struct new_page = NULL; if (unlikely(!new_page)) { + count_vm_event(THP_FAULT_FALLBACK); ret = do_huge_pmd_wp_page_fallback(mm, vma, address, pmd, orig_pmd, page, haddr); put_page(page); goto out; } + count_vm_event(THP_FAULT_ALLOC); if (unlikely(mem_cgroup_newpage_charge(new_page, mm, GFP_KERNEL))) { put_page(new_page); @@ -1390,6 +1395,7 @@ int split_huge_page(struct page *page) BUG_ON(!PageSwapBacked(page)); __split_huge_page(page, anon_vma); + count_vm_event(THP_SPLIT); BUG_ON(PageCompound(page)); out_unlock: @@ -1784,9 +1790,11 @@ static void collapse_huge_page(struct mm node, __GFP_OTHER_NODE); if (unlikely(!new_page)) { up_read(&mm->mmap_sem); + count_vm_event(THP_COLLAPSE_ALLOC_FAILED); *hpage = ERR_PTR(-ENOMEM); return; } + count_vm_event(THP_COLLAPSE_ALLOC); if (unlikely(mem_cgroup_newpage_charge(new_page, mm, GFP_KERNEL))) { up_read(&mm->mmap_sem); put_page(new_page); @@ -2151,8 +2159,11 @@ static void khugepaged_do_scan(struct pa #ifndef CONFIG_NUMA if (!*hpage) { *hpage = alloc_hugepage(khugepaged_defrag()); - if (unlikely(!*hpage)) + if (unlikely(!*hpage)) { + count_vm_event(THP_COLLAPSE_ALLOC_FAILED); break; + } + count_vm_event(THP_COLLAPSE_ALLOC); } #else if (IS_ERR(*hpage)) @@ -2192,8 +2203,11 @@ static struct page *khugepaged_alloc_hug do { hpage = alloc_hugepage(khugepaged_defrag()); - if (!hpage) + if (!hpage) { + count_vm_event(THP_COLLAPSE_ALLOC_FAILED); khugepaged_alloc_sleep(); + } else + count_vm_event(THP_COLLAPSE_ALLOC); } while (unlikely(!hpage) && likely(khugepaged_enabled())); return hpage; @@ -2210,8 +2224,11 @@ static void khugepaged_loop(void) while (likely(khugepaged_enabled())) { #ifndef CONFIG_NUMA hpage = khugepaged_alloc_hugepage(); - if (unlikely(!hpage)) + if (unlikely(!hpage)) { + count_vm_event(THP_COLLAPSE_ALLOC_FAILED); break; + } + count_vm_event(THP_COLLAPSE_ALLOC); #else if (IS_ERR(hpage)) { khugepaged_alloc_sleep(); diff -puN mm/vmstat.c~mm-add-vm-counters-for-transparent-hugepages mm/vmstat.c --- a/mm/vmstat.c~mm-add-vm-counters-for-transparent-hugepages +++ a/mm/vmstat.c @@ -951,7 +951,16 @@ static const char * const vmstat_text[] "unevictable_pgs_cleared", "unevictable_pgs_stranded", "unevictable_pgs_mlockfreed", + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + "thp_fault_alloc", + "thp_fault_fallback", + "thp_collapse_alloc", + "thp_collapse_alloc_failed", + "thp_split", #endif + +#endif /* CONFIG_VM_EVENTS_COUNTERS */ }; static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat, _ -- 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/