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 X-Spam-Level: X-Spam-Status: No, score=-3.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_GIT autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7CFB7C433E0 for ; Fri, 22 May 2020 00:19:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 583A92078B for ; Fri, 22 May 2020 00:19:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="bY2ZSbxF" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726785AbgEVATx (ORCPT ); Thu, 21 May 2020 20:19:53 -0400 Received: from userp2120.oracle.com ([156.151.31.85]:42624 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726650AbgEVATx (ORCPT ); Thu, 21 May 2020 20:19:53 -0400 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 04M0Hc2a047113; Fri, 22 May 2020 00:19:51 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id; s=corp-2020-01-29; bh=TkIFON2IgZpeHHKLjub7/YpGISvP5nDDyrQMNgGDESw=; b=bY2ZSbxF7faubK7FU+v8VjZ6udF2b+YZQrtd7U7YqEvWoWKmafEVfTCx8HFpXTcIJDge UKj1QLp1CYrE6ewsd3TJjYnfw4bObV+ZRIANN1pvhWd4idhDyLen82Mx2p+aEM/0rrMg eRgG3svIQ4byz0s944psFBxUm2n76cS54i2WMlkpBrifNIcWh9Or6Q9uuDodduH9H2Rs Qi3ql4HBQvkSIyPnYmY22eAELTG2Q2vfxFFrCHxA2U4pYxfShsSm9xKFYJdB+jJY7atA tJllxzvzNFcsdSj3A7u29govAujINOpqcsInFJ1b5a7u8/ZQOZB91xmO8mCS4N8Q8XcK EA== Received: from aserp3020.oracle.com (aserp3020.oracle.com [141.146.126.70]) by userp2120.oracle.com with ESMTP id 31501rhs4h-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Fri, 22 May 2020 00:19:51 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 04M0JFNg119641; Fri, 22 May 2020 00:19:50 GMT Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by aserp3020.oracle.com with ESMTP id 312t3cs2tw-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 22 May 2020 00:19:50 +0000 Received: from abhmp0005.oracle.com (abhmp0005.oracle.com [141.146.116.11]) by aserv0122.oracle.com (8.14.4/8.14.4) with ESMTP id 04M0JnVl013855; Fri, 22 May 2020 00:19:49 GMT Received: from ca-ldom147.us.oracle.com (/10.129.68.131) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 21 May 2020 17:19:49 -0700 From: Bijan Mottahedeh To: axboe@kernel.dk Cc: io-uring@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH 0/2] io_uring: call statx directly Date: Thu, 21 May 2020 17:19:35 -0700 Message-Id: <1590106777-5826-1-git-send-email-bijan.mottahedeh@oracle.com> X-Mailer: git-send-email 1.8.3.1 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9628 signatures=668686 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 bulkscore=0 spamscore=0 mlxlogscore=999 phishscore=0 mlxscore=0 malwarescore=0 suspectscore=3 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2005220000 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9628 signatures=668686 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 lowpriorityscore=0 spamscore=0 mlxlogscore=999 clxscore=1011 priorityscore=1501 cotscore=-2147483648 impostorscore=0 bulkscore=0 adultscore=0 malwarescore=0 phishscore=0 mlxscore=0 suspectscore=3 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2005220000 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org This patch set is a fix for the liburing statx test failure. The test fails with a "Miscompare between io_uring and statx" error because the statx system call path has additional processing in vfs_statx(): stat->result_mask |= STATX_MNT_ID; if (path.mnt->mnt_root == path.dentry) stat->attributes |= STATX_ATTR_MOUNT_ROOT; stat->attributes_mask |= STATX_ATTR_MOUNT_ROOT; which then results in different result_mask values. Allowing the system call to be invoked directly simplifies the io_uring interface and avoids potential future incompatibilities. I'm not sure if there was other reasoning fort not doing so initially. One issue I cannot account for is the difference in "used" memory reported by free(1) after running the statx a large (10000) number of times. The difference is significant ~100k and doesn't really change after dropping caches. I enabled memory leak detection and couldn't see anything related to the test. Bijan Mottahedeh (2): statx: allow the system call to be invoked from the kernel io_uring: call statx directly fs/internal.h | 2 ++ fs/io_uring.c | 53 +++++++---------------------------------------------- fs/stat.c | 32 +++++++++++++++++++------------- 3 files changed, 28 insertions(+), 59 deletions(-) -- 1.8.3.1