From patchwork Mon Sep 11 07:49:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?C=C3=A9dric_Le_Goater?= X-Patchwork-Id: 13378932 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 D7030EE57DF for ; Mon, 11 Sep 2023 07:51:26 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qfbgn-0003tZ-6i; Mon, 11 Sep 2023 03:50:33 -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 1qfbgj-0003qK-5v for qemu-devel@nongnu.org; Mon, 11 Sep 2023 03:50:29 -0400 Received: from mail.ozlabs.org ([2404:9400:2221:ea00::3] helo=gandalf.ozlabs.org) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qfbgd-00081W-PT for qemu-devel@nongnu.org; Mon, 11 Sep 2023 03:50:28 -0400 Received: from gandalf.ozlabs.org (mail.ozlabs.org [IPv6:2404:9400:2221:ea00::3]) by gandalf.ozlabs.org (Postfix) with ESMTP id 4Rkf5P1rpLz4xF3; Mon, 11 Sep 2023 17:50:17 +1000 (AEST) Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4Rkf5M3Qfmz4x5q; Mon, 11 Sep 2023 17:50:15 +1000 (AEST) From: =?utf-8?q?C=C3=A9dric_Le_Goater?= To: qemu-devel@nongnu.org Cc: Alex Williamson , Avihai Horon , =?utf-8?q?C=C3=A9dric_Le_Goater?= , YangHang Liu Subject: [PULL 02/13] sysemu: Add prepare callback to struct VMChangeStateEntry Date: Mon, 11 Sep 2023 09:49:57 +0200 Message-ID: <20230911075008.462712-3-clg@redhat.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230911075008.462712-1-clg@redhat.com> References: <20230911075008.462712-1-clg@redhat.com> MIME-Version: 1.0 Received-SPF: pass client-ip=2404:9400:2221:ea00::3; envelope-from=SRS0=GLJ6=E3=redhat.com=clg@ozlabs.org; helo=gandalf.ozlabs.org X-Spam_score_int: -39 X-Spam_score: -4.0 X-Spam_bar: ---- X-Spam_report: (-4.0 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.249, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_PASS=-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 From: Avihai Horon Add prepare callback to struct VMChangeStateEntry. The prepare callback is optional and can be set by the new function qemu_add_vm_change_state_handler_prio_full() that allows setting this callback in addition to the main callback. The prepare callbacks and main callbacks are called in two separate phases: First all prepare callbacks are called and only then all main callbacks are called. The purpose of the new prepare callback is to allow all devices to run a preliminary task before calling the devices' main callbacks. This will facilitate adding P2P support for VFIO migration where all VFIO devices need to be put in an intermediate P2P quiescent state before being stopped or started by the main callback. Signed-off-by: Avihai Horon Reviewed-by: Cédric Le Goater Tested-by: YangHang Liu Signed-off-by: Cédric Le Goater --- include/sysemu/runstate.h | 4 ++++ softmmu/runstate.c | 40 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 44 insertions(+) diff --git a/include/sysemu/runstate.h b/include/sysemu/runstate.h index 7beb29c2e2ac564bb002d208b125ab6269e097de..764a0fc6a4554857bcff339c668b48193b40c3a4 100644 --- a/include/sysemu/runstate.h +++ b/include/sysemu/runstate.h @@ -16,6 +16,10 @@ VMChangeStateEntry *qemu_add_vm_change_state_handler(VMChangeStateHandler *cb, void *opaque); VMChangeStateEntry *qemu_add_vm_change_state_handler_prio( VMChangeStateHandler *cb, void *opaque, int priority); +VMChangeStateEntry * +qemu_add_vm_change_state_handler_prio_full(VMChangeStateHandler *cb, + VMChangeStateHandler *prepare_cb, + void *opaque, int priority); VMChangeStateEntry *qdev_add_vm_change_state_handler(DeviceState *dev, VMChangeStateHandler *cb, void *opaque); diff --git a/softmmu/runstate.c b/softmmu/runstate.c index f3bd8628181303792629fa4079f09abf63fd9787..1652ed0439b4d39e5719d5b7caa002aa297789b6 100644 --- a/softmmu/runstate.c +++ b/softmmu/runstate.c @@ -271,6 +271,7 @@ void qemu_system_vmstop_request(RunState state) } struct VMChangeStateEntry { VMChangeStateHandler *cb; + VMChangeStateHandler *prepare_cb; void *opaque; QTAILQ_ENTRY(VMChangeStateEntry) entries; int priority; @@ -293,12 +294,39 @@ static QTAILQ_HEAD(, VMChangeStateEntry) vm_change_state_head = */ VMChangeStateEntry *qemu_add_vm_change_state_handler_prio( VMChangeStateHandler *cb, void *opaque, int priority) +{ + return qemu_add_vm_change_state_handler_prio_full(cb, NULL, opaque, + priority); +} + +/** + * qemu_add_vm_change_state_handler_prio_full: + * @cb: the main callback to invoke + * @prepare_cb: a callback to invoke before the main callback + * @opaque: user data passed to the callbacks + * @priority: low priorities execute first when the vm runs and the reverse is + * true when the vm stops + * + * Register a main callback function and an optional prepare callback function + * that are invoked when the vm starts or stops running. The main callback and + * the prepare callback are called in two separate phases: First all prepare + * callbacks are called and only then all main callbacks are called. As its + * name suggests, the prepare callback can be used to do some preparatory work + * before invoking the main callback. + * + * Returns: an entry to be freed using qemu_del_vm_change_state_handler() + */ +VMChangeStateEntry * +qemu_add_vm_change_state_handler_prio_full(VMChangeStateHandler *cb, + VMChangeStateHandler *prepare_cb, + void *opaque, int priority) { VMChangeStateEntry *e; VMChangeStateEntry *other; e = g_malloc0(sizeof(*e)); e->cb = cb; + e->prepare_cb = prepare_cb; e->opaque = opaque; e->priority = priority; @@ -333,10 +361,22 @@ void vm_state_notify(bool running, RunState state) trace_vm_state_notify(running, state, RunState_str(state)); if (running) { + QTAILQ_FOREACH_SAFE(e, &vm_change_state_head, entries, next) { + if (e->prepare_cb) { + e->prepare_cb(e->opaque, running, state); + } + } + QTAILQ_FOREACH_SAFE(e, &vm_change_state_head, entries, next) { e->cb(e->opaque, running, state); } } else { + QTAILQ_FOREACH_REVERSE_SAFE(e, &vm_change_state_head, entries, next) { + if (e->prepare_cb) { + e->prepare_cb(e->opaque, running, state); + } + } + QTAILQ_FOREACH_REVERSE_SAFE(e, &vm_change_state_head, entries, next) { e->cb(e->opaque, running, state); }