From nobody Wed Dec 17 22:44:07 2025 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 25B57C61D92 for ; Tue, 21 Nov 2023 12:03:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234468AbjKUMDZ (ORCPT ); Tue, 21 Nov 2023 07:03:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40838 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233846AbjKUMDW (ORCPT ); Tue, 21 Nov 2023 07:03:22 -0500 Received: from mx0b-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 634609C; Tue, 21 Nov 2023 04:03:19 -0800 (PST) Received: from pps.filterd (m0360072.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 3ALBc2v1023436; Tue, 21 Nov 2023 12:03:15 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding; s=pp1; bh=UbI3gRx2z11WJvUL9FqBRaWO2/YxaKCV9eYngKPduqY=; b=a3e0xRg0LtYV+rUXxM0fFf/nmsd9WAnKkD6Z/1WZ2zPez5g2YH1K9LXFkBJ/d1SQbkpI gNzZ3MirvbMIJoBdWcUdJLJrypKmosyJJSKIEyNY6u+yQGIBy1LRSUW2E5WOe0n2/0H0 +FJ2LXtgHK9daJgcCFDl0Rd3COC5hKNpmoiohyiDhqnUTlFIE+fiBYPomkN5+Irk8z3t lJXk/utmJolm19/gIQ0QljqjekAcHXg3UVlBBNkt65as+0MLUb2tgQwgl8ZUQfSdzquT 76BC3BkqrLyeXBmSxJ+zHr7zPiIdklEKhQ2+VhJI/LQJ8SSvWhyTHWOx6jF2O555Vmko lw== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3uguuj0ns6-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 21 Nov 2023 12:03:15 +0000 Received: from m0360072.ppops.net (m0360072.ppops.net [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 3ALBugM3015000; Tue, 21 Nov 2023 12:03:14 GMT Received: from ppma21.wdc07v.mail.ibm.com (5b.69.3da9.ip4.static.sl-reverse.com [169.61.105.91]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3uguuj0nrq-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 21 Nov 2023 12:03:14 +0000 Received: from pps.filterd (ppma21.wdc07v.mail.ibm.com [127.0.0.1]) by ppma21.wdc07v.mail.ibm.com (8.17.1.19/8.17.1.19) with ESMTP id 3ALBnHvF015865; Tue, 21 Nov 2023 12:03:14 GMT Received: from smtprelay03.fra02v.mail.ibm.com ([9.218.2.224]) by ppma21.wdc07v.mail.ibm.com (PPS) with ESMTPS id 3uf8knrd03-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 21 Nov 2023 12:03:13 +0000 Received: from smtpav07.fra02v.mail.ibm.com (smtpav07.fra02v.mail.ibm.com [10.20.54.106]) by smtprelay03.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 3ALC3AA217564168 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 21 Nov 2023 12:03:10 GMT Received: from smtpav07.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id B050E200CC; Tue, 21 Nov 2023 12:03:10 +0000 (GMT) Received: from smtpav07.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id A0C2E200CB; Tue, 21 Nov 2023 12:03:10 +0000 (GMT) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.152.85.9]) by smtpav07.fra02v.mail.ibm.com (Postfix) with ESMTPS; Tue, 21 Nov 2023 12:03:10 +0000 (GMT) Received: by tuxmaker.boeblingen.de.ibm.com (Postfix, from userid 55669) id 65D3DE0320; Tue, 21 Nov 2023 13:03:10 +0100 (CET) From: Alexander Gordeev To: Vishal Moola Cc: linux-mm@kvack.org, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, Gerald Schaefer , Heiko Carstens Subject: [PATCH] pgtable: do not expose _refcount field via ptdesc Date: Tue, 21 Nov 2023 13:03:10 +0100 Message-Id: <20231121120310.696335-1-agordeev@linux.ibm.com> X-Mailer: git-send-email 2.39.2 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-TM-AS-GCONF: 00 X-Proofpoint-GUID: YznpofG2GbqLlI3z4KWXDiYITvyETh0y X-Proofpoint-ORIG-GUID: hT0Li9jmuNkQcOhBZADPauH-OGkCMEb_ X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.987,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-11-21_05,2023-11-21_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxscore=0 priorityscore=1501 malwarescore=0 suspectscore=0 mlxlogscore=994 clxscore=1015 adultscore=0 spamscore=0 lowpriorityscore=0 impostorscore=0 phishscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2311060000 definitions=main-2311210094 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Since commit d08d4e7cd6bf ("s390/mm: use full 4KB page for 2KB PTE") _refcount field is not used for fragmented page tracking on s390 and there is no other code left that accesses this field explicitly. Suggested-by: Heiko Carstens Signed-off-by: Alexander Gordeev --- include/linux/mm_types.h | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 957ce38768b2..0330e0ddca11 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -401,11 +401,10 @@ FOLIO_MATCH(compound_head, _head_2a); * @pmd_huge_pte: Protected by ptdesc->ptl, used for THPs. * @__page_mapping: Aliases with page->mapping. Unused for page tables. * @pt_mm: Used for x86 pgds. - * @pt_frag_refcount: For fragmented page table tracking. Powerpc and s390= only. + * @pt_frag_refcount: For fragmented page table tracking. Powerpc only. * @_pt_pad_2: Padding to ensure proper alignment. * @ptl: Lock for the page table. * @__page_type: Same as page->page_type. Unused for page tables. - * @_refcount: Same as page refcount. Used for s390 page tables. * @pt_memcg_data: Memcg data. Tracked for page tables here. * * This struct overlays struct page for now. Do not modify without a good @@ -438,7 +437,7 @@ struct ptdesc { #endif }; unsigned int __page_type; - atomic_t _refcount; + unsigned int _pt_pad_3; #ifdef CONFIG_MEMCG unsigned long pt_memcg_data; #endif @@ -452,7 +451,6 @@ TABLE_MATCH(compound_head, _pt_pad_1); TABLE_MATCH(mapping, __page_mapping); TABLE_MATCH(rcu_head, pt_rcu_head); TABLE_MATCH(page_type, __page_type); -TABLE_MATCH(_refcount, _refcount); #ifdef CONFIG_MEMCG TABLE_MATCH(memcg_data, pt_memcg_data); #endif --=20 2.39.2