From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8126CCA5FC4 for ; Fri, 2 Oct 2026 09:57:06 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E5F896B00B4; Fri, 2 Oct 2026 05:57:01 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id DEA4C6B00B5; Fri, 2 Oct 2026 05:57:01 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CB1876B00B6; Fri, 2 Oct 2026 05:57:01 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id A14166B00B4 for ; Fri, 2 Oct 2026 05:57:01 -0400 (EDT) Received: from smtpin04.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 461D41C2763 for ; Fri, 2 Oct 2026 09:57:01 +0000 (UTC) X-FDA: 85277232642.04.026D03C Received: from mta0.migadu.com (out-118.mta0.migadu.com [91.218.175.118]) by imf14.hostedemail.com (Postfix) with ESMTP id 54C6F100003 for ; Fri, 2 Oct 2026 09:56:59 +0000 (UTC) Authentication-Results: imf14.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=V+HGp6iu; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf14.hostedemail.com: domain of usama.arif@linux.dev designates 91.218.175.118 as permitted sender) smtp.mailfrom=usama.arif@linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1790935019; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=V2NsbUurfee4vSeQVDWDVStNIM+u2hTDas5T+LMf7tQ=; b=R//lXh1VdH5K7YBRaF7NiwS3y15Y04TFNmxsyVf1alLtLgJfbUJaK9Y7Y6MaTK2lOUXEPM stbkEdavjF9b7uyXuEK//Mv6qwPf2I70BFrhd5LlTgbtdvPhRbDJqFtpaRe8vAXLgxJ/Fp zUU21+OI733TFjABJAy9wnmkMqXRWn4= ARC-Authentication-Results: i=1; imf14.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=V+HGp6iu; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf14.hostedemail.com: domain of usama.arif@linux.dev designates 91.218.175.118 as permitted sender) smtp.mailfrom=usama.arif@linux.dev ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1790935019; b=YCjmY4ZnnN5FLrHqHPrdZwcSqUfDUgCwS02hzNlAb503W5x23piqtWeVuTH6tIr62BkXYj 2ilbQ0te2RRgetraihHMb3Qp2AMmcr1O+BV5FE78Qh1vReVybebHduiHy1SIyjFmT9KUlk 3MdSYbQ50sVHYNBaRr+qXwRfXs/q6ls= X-Envelope-To: linux-mm@kvack.org DKIM-Signature: a=rsa-sha256; bh=U7fl/g2rQtBLEOOrRTOeLDCwF2LzhxQL9fohkaqezco=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1790935018; v=1; x=1791539818; b=V+HGp6iuRhxNJlToyyu4Db5rTKQ0jAz7Rn/JbvJ5z05atfpJfZbnbUv/vTkap/DEdJbvXJMi 2m1c2ACvb3JW3sh3jhhVcxiczSrkIdiSP8VUy2B1gSI5dFBt54WgUhu2OT7RHP9BryHN0/taxCz Q84662Jr5/kV7aIUeGEVhtR0= X-Envelope-To: linux-mm@kvack.org Received: by mta11.migadu.com with ESMTPS id 780e5e8d7edcc9b9; Fri, 02 Oct 2026 09:56:57 +0000 X-Mizu-Trace-ID: 780e5e8d7edcc9b9 X-Migadu-Flow: FLOW_OUT From: Usama Arif To: Andrew Morton , david@kernel.org, chrisl@kernel.org, kasong@tencent.com, ljs@kernel.org, ziy@nvidia.com, linux-mm@kvack.org Cc: ying.huang@linux.alibaba.com, Baoquan He , willy@infradead.org, youngjun.park@lge.com, hannes@cmpxchg.org, riel@surriel.com, shakeel.butt@linux.dev, alex@ghiti.fr, kas@kernel.org, baohua@kernel.org, dev.jain@arm.com, baolin.wang@linux.alibaba.com, Nico Pache , Liam R. Howlett , ryan.roberts@arm.com, Vlastimil Babka , lance.yang@linux.dev, linux-kernel@vger.kernel.org, nphamcs@gmail.com, shikemeng@huaweicloud.com, yosry@kernel.org, qi.zheng@linux.dev, luizcap@redhat.com, kernel-team@meta.com, Usama Arif Subject: [PATCH v8 16/30] fs/proc: account PMD swap entries in smaps Date: Fri, 2 Oct 2026 02:52:30 -0700 Message-ID: <20261002095503.3585565-17-usama.arif@linux.dev> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20261002095503.3585565-1-usama.arif@linux.dev> References: <20261002095503.3585565-1-usama.arif@linux.dev> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspam-User: X-Stat-Signature: 6mob4drhafs6p6whmps4eej7xppznufs X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 54C6F100003 X-HE-Tag: 1790935019-62641 X-HE-Meta: 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 Bpu3VY5H pu35f1qKYBJBqLJjG4r/Ifmi6kmSKXvqh7Ap76ZDyIb2nNR4qlQ7Xa8FUt9dygbUjh6IUXG4Bsv1XIwA9edneSzCUwZmJkuoPsIqCncgN5cT4cuHqbXfnzA4Z/PdukGuLzgTr+67SFwCxnTgZCw0b6JoLDr1SDFfc+1qbz/sZr6aWoO/8M2u8dZG9u9pA4p2cxFBkkxbIZ7uUoW5Q9ekBbM0FCk4nvBfvDZyCmGIcdlXQLzY= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: smaps_pmd_entry() derives a page from a non-present PMD and gives up if it cannot. A PMD swap entry carries no PFN, so a swapped-out THP is missing from both Swap and SwapPss. The slots of a PMD swap entry can have different swap reference counts, so SwapPss has to be computed one slot at a time rather than divided once. Factor that loop out of smaps_pte_entry() and call it from both levels, then return early: a swapped-out THP is not resident and must not be added to AnonHugePages or Rss. While touching PMD softleaf accounting, match the PTE path and treat device-private PMD entries as fake-present. This lets smaps use mapcount-based PSS and private/shared accounting instead of treating them like migration entries. Signed-off-by: Usama Arif --- fs/proc/task_mmu.c | 41 ++++++++++++++++++++++++++++------------- 1 file changed, 28 insertions(+), 13 deletions(-) diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 24425e2308951..97c3fd7acf15d 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -957,6 +957,25 @@ static void smaps_pte_hole_lookup(unsigned long addr, struct mm_walk *walk) #endif } +static void smaps_account_swap(struct mem_size_stats *mss, + softleaf_t entry, unsigned long nr_pages) +{ + mss->swap += nr_pages << PAGE_SHIFT; + do { + int swapcount = swp_swapcount(entry); + + if (swapcount >= 2) { + u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT; + + do_div(pss_delta, swapcount); + mss->swap_pss += pss_delta; + } else { + mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT; + } + entry.val++; + } while (--nr_pages); +} + static void smaps_pte_entry(pte_t *pte, unsigned long addr, struct mm_walk *walk) { @@ -978,18 +997,7 @@ static void smaps_pte_entry(pte_t *pte, unsigned long addr, const softleaf_t entry = softleaf_from_pte(ptent); if (softleaf_is_swap(entry)) { - int mapcount; - - mss->swap += PAGE_SIZE; - mapcount = swp_swapcount(entry); - if (mapcount >= 2) { - u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT; - - do_div(pss_delta, mapcount); - mss->swap_pss += pss_delta; - } else { - mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT; - } + smaps_account_swap(mss, entry, 1); } else if (softleaf_has_pfn(entry)) { if (softleaf_is_device_private(entry)) present = true; @@ -1022,8 +1030,15 @@ static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, } else if (unlikely(thp_migration_supported())) { const softleaf_t entry = softleaf_from_pmd(*pmd); - if (softleaf_has_pfn(entry)) + if (softleaf_is_swap(entry)) { + smaps_account_swap(mss, entry, HPAGE_PMD_NR); + return; + } + if (softleaf_has_pfn(entry)) { + if (softleaf_is_device_private(entry)) + present = true; page = softleaf_to_page(entry); + } } if (IS_ERR_OR_NULL(page)) return; -- 2.53.0-Meta