From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754546AbeEWI1E (ORCPT ); Wed, 23 May 2018 04:27:04 -0400 Received: from mga03.intel.com ([134.134.136.65]:7717 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932111AbeEWI06 (ORCPT ); Wed, 23 May 2018 04:26:58 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.49,432,1520924400"; d="scan'208";a="57726089" From: "Huang, Ying" To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Huang Ying , "Kirill A. Shutemov" , Andrea Arcangeli , Michal Hocko , Johannes Weiner , Shaohua Li , Hugh Dickins , Minchan Kim , Rik van Riel , Dave Hansen , Naoya Horiguchi , Zi Yan Subject: [PATCH -mm -V3 10/21] mm, THP, swap: Support to count THP swapin and its fallback Date: Wed, 23 May 2018 16:26:14 +0800 Message-Id: <20180523082625.6897-11-ying.huang@intel.com> X-Mailer: git-send-email 2.16.1 In-Reply-To: <20180523082625.6897-1-ying.huang@intel.com> References: <20180523082625.6897-1-ying.huang@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Huang Ying 2 new /proc/vmstat fields are added, "thp_swapin" and "thp_swapin_fallback" to count swapin a THP from swap device as a whole and fallback to normal page swapin. Signed-off-by: "Huang, Ying" Cc: "Kirill A. Shutemov" Cc: Andrea Arcangeli Cc: Michal Hocko Cc: Johannes Weiner Cc: Shaohua Li Cc: Hugh Dickins Cc: Minchan Kim Cc: Rik van Riel Cc: Dave Hansen Cc: Naoya Horiguchi Cc: Zi Yan --- Documentation/vm/transhuge.rst | 10 +++++++++- include/linux/vm_event_item.h | 2 ++ mm/huge_memory.c | 4 +++- mm/page_io.c | 15 ++++++++++++--- mm/vmstat.c | 2 ++ 5 files changed, 28 insertions(+), 5 deletions(-) diff --git a/Documentation/vm/transhuge.rst b/Documentation/vm/transhuge.rst index 2c6867fca6ff..a87b1d880cd4 100644 --- a/Documentation/vm/transhuge.rst +++ b/Documentation/vm/transhuge.rst @@ -360,10 +360,18 @@ thp_swpout piece without splitting. thp_swpout_fallback - is incremented if a huge page has to be split before swapout. + is incremented if a huge page is split before swapout. Usually because failed to allocate some continuous swap space for the huge page. +thp_swpin + is incremented every time a huge page is swapin in one piece + without splitting. + +thp_swpin_fallback + is incremented if a huge page is split during swapin. Usually + because failed to allocate a huge page. + As the system ages, allocating huge pages may be expensive as the system uses memory compaction to copy data around memory to free a huge page for use. There are some counters in ``/proc/vmstat`` to help diff --git a/include/linux/vm_event_item.h b/include/linux/vm_event_item.h index 5c7f010676a7..7b438548a78e 100644 --- a/include/linux/vm_event_item.h +++ b/include/linux/vm_event_item.h @@ -88,6 +88,8 @@ enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT, THP_ZERO_PAGE_ALLOC_FAILED, THP_SWPOUT, THP_SWPOUT_FALLBACK, + THP_SWPIN, + THP_SWPIN_FALLBACK, #endif #ifdef CONFIG_MEMORY_BALLOON BALLOON_INFLATE, diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 8303fa021c42..c2437914c632 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1664,8 +1664,10 @@ int do_huge_pmd_swap_page(struct vm_fault *vmf, pmd_t orig_pmd) /* swapoff occurs under us */ } else if (ret == -EINVAL) ret = 0; - else + else { + count_vm_event(THP_SWPIN_FALLBACK); goto fallback; + } } delayacct_clear_flag(DELAYACCT_PF_SWAPIN); goto out; diff --git a/mm/page_io.c b/mm/page_io.c index b41cf9644585..96277058681e 100644 --- a/mm/page_io.c +++ b/mm/page_io.c @@ -347,6 +347,15 @@ int __swap_writepage(struct page *page, struct writeback_control *wbc, return ret; } +static inline void count_swpin_vm_event(struct page *page) +{ +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + if (unlikely(PageTransHuge(page))) + count_vm_event(THP_SWPIN); +#endif + count_vm_events(PSWPIN, hpage_nr_pages(page)); +} + int swap_readpage(struct page *page, bool synchronous) { struct bio *bio; @@ -370,7 +379,7 @@ int swap_readpage(struct page *page, bool synchronous) ret = mapping->a_ops->readpage(swap_file, page); if (!ret) - count_vm_event(PSWPIN); + count_swpin_vm_event(page); return ret; } @@ -381,7 +390,7 @@ int swap_readpage(struct page *page, bool synchronous) unlock_page(page); } - count_vm_event(PSWPIN); + count_swpin_vm_event(page); return 0; } @@ -400,7 +409,7 @@ int swap_readpage(struct page *page, bool synchronous) get_task_struct(current); bio->bi_private = current; bio_set_op_attrs(bio, REQ_OP_READ, 0); - count_vm_event(PSWPIN); + count_swpin_vm_event(page); bio_get(bio); qc = submit_bio(bio); while (synchronous) { diff --git a/mm/vmstat.c b/mm/vmstat.c index 75eda9c2b260..259c7bddbb6e 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -1263,6 +1263,8 @@ const char * const vmstat_text[] = { "thp_zero_page_alloc_failed", "thp_swpout", "thp_swpout_fallback", + "thp_swpin", + "thp_swpin_fallback", #endif #ifdef CONFIG_MEMORY_BALLOON "balloon_inflate", -- 2.16.1