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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7A973CA0EDC for ; Thu, 14 Aug 2025 17:20:14 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1umbaA-0005Vf-5C; Thu, 14 Aug 2025 13:17:42 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1umba7-0005U1-2G for qemu-devel@nongnu.org; Thu, 14 Aug 2025 13:17:39 -0400 Received: from mx0a-00069f02.pphosted.com ([205.220.165.32]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1umba4-0002qF-8y for qemu-devel@nongnu.org; Thu, 14 Aug 2025 13:17:38 -0400 Received: from pps.filterd (m0246627.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 57ECg3g0020157; Thu, 14 Aug 2025 17:17:34 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=cc :date:from:in-reply-to:message-id:references:subject:to; s= corp-2025-04-25; bh=4QWKzsape/wPi0214a2KMaISzaNbmpDGJwl9PMlhRvc=; b= pJFwSz/nsPDW92T1bZUp8w2cdQwDS+iBPrqSYiLV1fpylgHDuY8QUtycyszT+ATQ eW0Sk2PEtKqbI/5nivZ9rnarcur26Vb47lMDpF40AXqfb04LvlsjvtOx4NdVtVEQ 2mry08XV2nA5wHmOzdmeF+iRWMP9modLmL0B1b5kodP/MUHIaoK9iVbN8Fa4cP+i oyVXdlsB0h2SlqBMhu/935WcfUikCyte3hED8tOxTu0xyCKcybUfkT8IF2ze6cpe z4jZnK5O91rW/4IFdQHInRa4iwaOHgohLpDeSdnXAmFcEFI54jLjLojdNZJSA6R1 RlEDzEWfgg9nR5QQ7d4UZA== Received: from iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta01.appoci.oracle.com [130.35.100.223]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 48dvx4jhap-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 14 Aug 2025 17:17:34 +0000 (GMT) Received: from pps.filterd (iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (8.18.1.2/8.18.1.2) with ESMTP id 57EGs9gL010435; Thu, 14 Aug 2025 17:17:32 GMT Received: from pps.reinject (localhost [127.0.0.1]) by iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTPS id 48dvskbs1k-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 14 Aug 2025 17:17:32 +0000 Received: from iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 57EHGwuI038225; Thu, 14 Aug 2025 17:17:32 GMT Received: from ca-dev63.us.oracle.com (ca-dev63.us.oracle.com [10.211.8.221]) by iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTP id 48dvskbrx5-7; Thu, 14 Aug 2025 17:17:32 +0000 From: Steve Sistare To: qemu-devel@nongnu.org Cc: Fabiano Rosas , Peter Xu , Markus Armbruster , Paolo Bonzini , Eric Blake , "Dr. David Alan Gilbert" , Steve Sistare Subject: [PATCH V3 6/9] migration: cpr-exec save and load Date: Thu, 14 Aug 2025 10:17:20 -0700 Message-Id: <1755191843-283480-7-git-send-email-steven.sistare@oracle.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1755191843-283480-1-git-send-email-steven.sistare@oracle.com> References: <1755191843-283480-1-git-send-email-steven.sistare@oracle.com> X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1099,Hydra:6.1.9,FMLib:17.12.80.40 definitions=2025-08-13_02,2025-08-14_01,2025-03-28_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxlogscore=999 bulkscore=0 adultscore=0 mlxscore=0 phishscore=0 spamscore=0 suspectscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2507300000 definitions=main-2508140147 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwODE0MDE0OCBTYWx0ZWRfX4zdlPyL0Mo+N 8cHbzNhW8/p776A9LBsLQ9rDz+yl2srA+YniBXG66GFapj7ZbsL08huA+9aODdTfmELjZCbNp9z j7LwgpXlMJFfU/2y4il9nQsLpRhFeA+54AWh59jQJ+OwRoWo7xwyEhc61IKIMFnqjpVMpfsZsVM gmgfZcK+vmQxV2T6XLDqj20ulngXWcg7cxhefPw/pr51vzBOX259NQlXWCvCZ3IO7axhqV4zKYG cHrbgPXRVjXcTKukzwAZ0d0e2BdYRvvP9+nNY0IcavLOCraf2qkSYUE1rbiOHCYNJ+ZgExar7Sv ROi0HGE0ILErQiWCHjrfYLLZ0nvsRwRHPCxqdA6OFTigDkBqgXJxg+BarzC5r8xNbnoRa+GYKiJ +yNXEGP7WE/yJKF0SU8FVwjfSHNGKKcPq+yjGSEwmbPARs3p6kotFImCBBVDkBlco4WpsbGv X-Authority-Analysis: v=2.4 cv=eIsTjGp1 c=1 sm=1 tr=0 ts=689e1a2e b=1 cx=c_pps a=zPCbziy225d3KhSqZt3L1A==:117 a=zPCbziy225d3KhSqZt3L1A==:17 a=2OwXVqhp2XgA:10 a=yPCof4ZbAAAA:8 a=mt9KrOKPv6uyc6Gi5S4A:9 cc=ntf awl=host:12069 X-Proofpoint-GUID: 4Bn6d7IUCNIxCvqlLEhYqV6KIs-DFKzH X-Proofpoint-ORIG-GUID: 4Bn6d7IUCNIxCvqlLEhYqV6KIs-DFKzH Received-SPF: pass client-ip=205.220.165.32; envelope-from=steven.sistare@oracle.com; helo=mx0a-00069f02.pphosted.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_MED=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org To preserve CPR state across exec, create a QEMUFile based on a memfd, and keep the memfd open across exec. Save the value of the memfd in an environment variable so post-exec QEMU can find it. These new functions are called in a subsequent patch. Signed-off-by: Steve Sistare --- include/migration/cpr.h | 5 +++ migration/cpr-exec.c | 94 +++++++++++++++++++++++++++++++++++++++++++++++++ migration/meson.build | 1 + 3 files changed, 100 insertions(+) create mode 100644 migration/cpr-exec.c diff --git a/include/migration/cpr.h b/include/migration/cpr.h index f4fc5ca..aaeec02 100644 --- a/include/migration/cpr.h +++ b/include/migration/cpr.h @@ -54,4 +54,9 @@ int cpr_get_fd_param(const char *name, const char *fdname, int index, bool cpr, QEMUFile *cpr_transfer_output(MigrationChannel *channel, Error **errp); QEMUFile *cpr_transfer_input(MigrationChannel *channel, Error **errp); +QEMUFile *cpr_exec_output(Error **errp); +QEMUFile *cpr_exec_input(Error **errp); +void cpr_exec_persist_state(QEMUFile *f); +bool cpr_exec_has_state(void); +void cpr_exec_unpersist_state(void); #endif diff --git a/migration/cpr-exec.c b/migration/cpr-exec.c new file mode 100644 index 0000000..2c32e9c --- /dev/null +++ b/migration/cpr-exec.c @@ -0,0 +1,94 @@ +/* + * Copyright (c) 2021-2025 Oracle and/or its affiliates. + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#include "qemu/osdep.h" +#include "qemu/cutils.h" +#include "qemu/memfd.h" +#include "qapi/error.h" +#include "io/channel-file.h" +#include "io/channel-socket.h" +#include "migration/cpr.h" +#include "migration/qemu-file.h" +#include "migration/misc.h" +#include "migration/vmstate.h" +#include "system/runstate.h" + +#define CPR_EXEC_STATE_NAME "QEMU_CPR_EXEC_STATE" + +static QEMUFile *qemu_file_new_fd_input(int fd, const char *name) +{ + g_autoptr(QIOChannelFile) fioc = qio_channel_file_new_fd(fd); + QIOChannel *ioc = QIO_CHANNEL(fioc); + qio_channel_set_name(ioc, name); + return qemu_file_new_input(ioc); +} + +static QEMUFile *qemu_file_new_fd_output(int fd, const char *name) +{ + g_autoptr(QIOChannelFile) fioc = qio_channel_file_new_fd(fd); + QIOChannel *ioc = QIO_CHANNEL(fioc); + qio_channel_set_name(ioc, name); + return qemu_file_new_output(ioc); +} + +void cpr_exec_persist_state(QEMUFile *f) +{ + QIOChannelFile *fioc = QIO_CHANNEL_FILE(qemu_file_get_ioc(f)); + int mfd = dup(fioc->fd); + char val[16]; + + /* Remember mfd in environment for post-exec load */ + qemu_clear_cloexec(mfd); + snprintf(val, sizeof(val), "%d", mfd); + g_setenv(CPR_EXEC_STATE_NAME, val, 1); +} + +static int cpr_exec_find_state(void) +{ + const char *val = g_getenv(CPR_EXEC_STATE_NAME); + int mfd; + + assert(val); + g_unsetenv(CPR_EXEC_STATE_NAME); + assert(!qemu_strtoi(val, NULL, 10, &mfd)); + return mfd; +} + +bool cpr_exec_has_state(void) +{ + return g_getenv(CPR_EXEC_STATE_NAME) != NULL; +} + +void cpr_exec_unpersist_state(void) +{ + int mfd; + const char *val = g_getenv(CPR_EXEC_STATE_NAME); + + g_unsetenv(CPR_EXEC_STATE_NAME); + assert(val); + assert(!qemu_strtoi(val, NULL, 10, &mfd)); + close(mfd); +} + +QEMUFile *cpr_exec_output(Error **errp) +{ + int mfd = memfd_create(CPR_EXEC_STATE_NAME, 0); + + if (mfd < 0) { + error_setg_errno(errp, errno, "memfd_create failed"); + return NULL; + } + + return qemu_file_new_fd_output(mfd, CPR_EXEC_STATE_NAME); +} + +QEMUFile *cpr_exec_input(Error **errp) +{ + int mfd = cpr_exec_find_state(); + + lseek(mfd, 0, SEEK_SET); + return qemu_file_new_fd_input(mfd, CPR_EXEC_STATE_NAME); +} diff --git a/migration/meson.build b/migration/meson.build index 276da3b..6087ccc 100644 --- a/migration/meson.build +++ b/migration/meson.build @@ -16,6 +16,7 @@ system_ss.add(files( 'channel-block.c', 'cpr.c', 'cpr-transfer.c', + 'cpr-exec.c', 'cpu-throttle.c', 'dirtyrate.c', 'exec.c', -- 1.8.3.1