From patchwork Wed Oct 11 09:22:02 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Juan Quintela X-Patchwork-Id: 13417005 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 B5502CD6E54 for ; Wed, 11 Oct 2023 09:35:09 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qqVS6-0005K2-IT; Wed, 11 Oct 2023 05:24:27 -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 1qqVS2-00057q-Eg for qemu-devel@nongnu.org; Wed, 11 Oct 2023 05:24:23 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qqVRz-0005E1-SD for qemu-devel@nongnu.org; Wed, 11 Oct 2023 05:24:22 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1697016258; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=3QEULf3jbHJZ303L8i4uGaQWAe3u6wBDVDebIdN2EkE=; b=QKuJa6RPb3BgAvPj/9yUQPruIxYxK8nZyobHs/Qx1bvWrSgUTVnIqJVpY/5n9c5976vJKp Wi24w6MpDKl9Kkn1xt/aNVRZaqM6TSxOQzSYSpF7J7HoDXvwz5yKVt7QaammRTp+iv8sWv nbIYrmOs9sH60+fe33XH1+e/xRD4h2E= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-251-2pbpgowaP5WMYnFmErDwkw-1; Wed, 11 Oct 2023 05:24:16 -0400 X-MC-Unique: 2pbpgowaP5WMYnFmErDwkw-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 3D86F811E7B; Wed, 11 Oct 2023 09:24:16 +0000 (UTC) Received: from secure.mitica (unknown [10.39.195.75]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7F3D11C060AE; Wed, 11 Oct 2023 09:24:14 +0000 (UTC) From: Juan Quintela To: qemu-devel@nongnu.org Cc: Laurent Vivier , Peter Xu , Paolo Bonzini , Markus Armbruster , Juan Quintela , Thomas Huth , Li Zhijian , Leonardo Bras , Eric Blake , Fabiano Rosas Subject: [PULL 64/65] migration: Remember num of ramblocks to sync during recovery Date: Wed, 11 Oct 2023 11:22:02 +0200 Message-ID: <20231011092203.1266-65-quintela@redhat.com> In-Reply-To: <20231011092203.1266-1-quintela@redhat.com> References: <20231011092203.1266-1-quintela@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.7 Received-SPF: pass client-ip=170.10.129.124; envelope-from=quintela@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=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 From: Peter Xu Instead of only relying on the count of rp_sem, make the counter be part of RAMState so it can be used in both threads to synchronize on the process. rp_sem will be further reused in follow up patches, as a way to kick the main thread, e.g., on recovery failures. Reviewed-by: Fabiano Rosas Reviewed-by: Juan Quintela Signed-off-by: Peter Xu Signed-off-by: Juan Quintela Message-ID: <20231004220240.167175-7-peterx@redhat.com> --- migration/ram.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index e4bfd39f08..6c40d9af0c 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -394,6 +394,14 @@ struct RAMState { /* Queue of outstanding page requests from the destination */ QemuMutex src_page_req_mutex; QSIMPLEQ_HEAD(, RAMSrcPageRequest) src_page_requests; + + /* + * This is only used when postcopy is in recovery phase, to communicate + * between the migration thread and the return path thread on dirty + * bitmap synchronizations. This field is unused in other stages of + * RAM migration. + */ + unsigned int postcopy_bmap_sync_requested; }; typedef struct RAMState RAMState; @@ -4119,20 +4127,20 @@ static int ram_dirty_bitmap_sync_all(MigrationState *s, RAMState *rs) { RAMBlock *block; QEMUFile *file = s->to_dst_file; - int ramblock_count = 0; trace_ram_dirty_bitmap_sync_start(); + qatomic_set(&rs->postcopy_bmap_sync_requested, 0); RAMBLOCK_FOREACH_NOT_IGNORED(block) { qemu_savevm_send_recv_bitmap(file, block->idstr); trace_ram_dirty_bitmap_request(block->idstr); - ramblock_count++; + qatomic_inc(&rs->postcopy_bmap_sync_requested); } trace_ram_dirty_bitmap_sync_wait(); /* Wait until all the ramblocks' dirty bitmap synced */ - while (ramblock_count--) { + while (qatomic_read(&rs->postcopy_bmap_sync_requested)) { qemu_sem_wait(&s->rp_state.rp_sem); } @@ -4159,6 +4167,7 @@ int ram_dirty_bitmap_reload(MigrationState *s, RAMBlock *block) unsigned long *le_bitmap, nbits = block->used_length >> TARGET_PAGE_BITS; uint64_t local_size = DIV_ROUND_UP(nbits, 8); uint64_t size, end_mark; + RAMState *rs = ram_state; trace_ram_dirty_bitmap_reload_begin(block->idstr); @@ -4225,6 +4234,8 @@ int ram_dirty_bitmap_reload(MigrationState *s, RAMBlock *block) /* We'll recalculate migration_dirty_pages in ram_state_resume_prepare(). */ trace_ram_dirty_bitmap_reload_complete(block->idstr); + qatomic_dec(&rs->postcopy_bmap_sync_requested); + /* * We succeeded to sync bitmap for current ramblock. If this is * the last one to sync, we need to notify the main send thread.