From patchwork Fri Oct 28 10:39:12 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nikolay Borisov X-Patchwork-Id: 1695962 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=suse.com header.i=@suse.com header.a=rsa-sha256 header.s=susede1 header.b=eyHxWG6f; dkim-atps=neutral Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4MzJyS6DThz23lB for ; Fri, 28 Oct 2022 21:42:08 +1100 (AEDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ooMm0-0002HH-TR; Fri, 28 Oct 2022 06:39:36 -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 1ooMlp-0002CO-97 for qemu-devel@nongnu.org; Fri, 28 Oct 2022 06:39:25 -0400 Received: from smtp-out1.suse.de ([195.135.220.28]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1ooMln-00021H-Ju for qemu-devel@nongnu.org; Fri, 28 Oct 2022 06:39:25 -0400 Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 7A3A621982; Fri, 28 Oct 2022 10:39:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1666953562; h=from:from:reply-to: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=cn0gocB5kw66POTC/oATjK5+Jyeej+1QhPCIMPRKVeo=; b=eyHxWG6f/G4w/xkFb2vpMpLE3urMPClupGV+i1teNCwHJBAo0RqV+IfaTPujRHDLmsv0VU fVFBBdYc2TPvVbJ63nzM3KI3YcNNdKGFNsoWoE5CofzIWyG2PJSfoM1dH+UUUGNFUf/c37 Lcv+nKoExZBM15fXLA1t1oE3rAq5p4Y= Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 1652813A6E; Fri, 28 Oct 2022 10:39:22 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id IK/JAlqxW2PVPwAAMHmgww (envelope-from ); Fri, 28 Oct 2022 10:39:22 +0000 From: Nikolay Borisov To: dgilbert@redhat.com, berrange@redhat.com Cc: qemu-devel@nongnu.org, jfehlig@suse.com, Claudio.Fontana@suse.com, dfaggioli@suse.com, Nikolay Borisov Subject: [PATCH v3 12/14] migration: Add support for 'fixed-ram' migration restore Date: Fri, 28 Oct 2022 13:39:12 +0300 Message-Id: <20221028103914.908728-13-nborisov@suse.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221028103914.908728-1-nborisov@suse.com> References: <20221028103914.908728-1-nborisov@suse.com> MIME-Version: 1.0 Received-SPF: pass client-ip=195.135.220.28; envelope-from=nborisov@suse.com; helo=smtp-out1.suse.de X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, 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: , Sender: "Qemu-devel" Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Add the necessary code to parse the format changes for 'fixed-ram' capability. One of the more notable changes in behavior is that in the 'fixed-ram' case ram pages are restored in one go rather than constantly looping through the migration stream. Also due to idiosyncrasies of the format I have added the 'ram_migrated' since it was easier to simply return directly from ->load_state rather than introducing more conditionals around the code to prevent ->load_state being called multiple times (from qemu_loadvm_section_start_full/qemu_loadvm_section_part_end i.e. from multiple QEMU_VM_SECTION_(PART|END) flags). Signed-off-by: Nikolay Borisov --- migration/migration.h | 2 + migration/ram.c | 95 ++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 95 insertions(+), 2 deletions(-) diff --git a/migration/migration.h b/migration/migration.h index 9aab1b16f407..7a832d072415 100644 --- a/migration/migration.h +++ b/migration/migration.h @@ -96,6 +96,8 @@ struct MigrationIncomingState { bool have_listen_thread; QemuThread listen_thread; + bool ram_migrated; + /* For the kernel to send us notifications */ int userfault_fd; /* To notify the fault_thread to wake, e.g., when need to quit */ diff --git a/migration/ram.c b/migration/ram.c index 1dd68c221667..e085a2431f88 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -4330,6 +4330,90 @@ static int parse_ramblocks(QEMUFile *f, ram_addr_t total_ram_bytes) return ret; } + +static int parse_ramblocks_fixed_ram(QEMUFile *f) +{ + int ret = 0; + + while (!ret) { + char id[256]; + RAMBlock *block; + ram_addr_t length; + unsigned long clear_bit_idx; + long num_pages, bitmap_size; + int len = qemu_get_byte(f); + g_autofree unsigned long *dirty_bitmap = NULL; + + qemu_get_buffer(f, (uint8_t *)id, len); + id[len] = 0; + length = qemu_get_be64(f); + + block = qemu_ram_block_by_name(id); + if (block) { + ret = parse_ramblock(f, block, length); + if (ret < 0) { + return ret; + } + } else { + error_report("Unknown ramblock \"%s\", cannot accept " + "migration", id); + ret = -EINVAL; + continue; + } + + /* 1. read the bitmap size */ + num_pages = length >> TARGET_PAGE_BITS; + bitmap_size = qemu_get_be32(f); + + assert(bitmap_size == BITS_TO_LONGS(num_pages)*sizeof(unsigned long)); + + block->pages_offset = qemu_get_be64(f); + + /* 2. read the actual bitmap */ + dirty_bitmap = g_malloc0(bitmap_size); + if (qemu_get_buffer(f, (uint8_t *)dirty_bitmap, bitmap_size) != bitmap_size) { + error_report("Error parsing dirty bitmap"); + return -EINVAL; + } + +#define BUFSIZE (4*1024*1024) + for (unsigned long set_bit_idx = find_first_bit(dirty_bitmap, num_pages); + set_bit_idx < num_pages; + set_bit_idx = find_next_bit(dirty_bitmap, num_pages, clear_bit_idx + 1)) { + + clear_bit_idx = find_next_zero_bit(dirty_bitmap, num_pages, set_bit_idx + 1); + unsigned long len = TARGET_PAGE_SIZE * (clear_bit_idx - set_bit_idx); + ram_addr_t offset = set_bit_idx << TARGET_PAGE_BITS; + + for (size_t read = 0, completed = 0; completed < len; offset += read) { + void *host = host_from_ram_block_offset(block, offset); + size_t read_len = MIN(len, BUFSIZE); + + read = qemu_get_buffer_at(f, host, read_len, + block->pages_offset + offset); + completed += read; + } + } + + /* Skip pages array */ + qemu_set_offset(f, block->pages_offset + length, SEEK_SET); + + /* Check if this is the last ramblock */ + if (qemu_get_be64(f) == RAM_SAVE_FLAG_EOS) { + ret = 1; + } else { + /* + * If not, adjust the internal file index to account for the + * previous 64 bit read + */ + qemu_file_skip(f, -8); + ret = 0; + } + } + + return ret; +} + /** * ram_load_precopy: load pages in precopy case * @@ -4349,7 +4433,7 @@ static int ram_load_precopy(QEMUFile *f) invalid_flags |= RAM_SAVE_FLAG_COMPRESS_PAGE; } - while (!ret && !(flags & RAM_SAVE_FLAG_EOS)) { + while (!ret && !(flags & RAM_SAVE_FLAG_EOS) && !mis->ram_migrated) { ram_addr_t addr; void *host = NULL, *host_bak = NULL; uint8_t ch; @@ -4421,7 +4505,14 @@ static int ram_load_precopy(QEMUFile *f) switch (flags & ~RAM_SAVE_FLAG_CONTINUE) { case RAM_SAVE_FLAG_MEM_SIZE: - ret = parse_ramblocks(f, addr); + if (migrate_fixed_ram()) { + ret = parse_ramblocks_fixed_ram(f); + if (ret == 1) { + mis->ram_migrated = true; + } + } else { + ret = parse_ramblocks(f, addr); + } break; case RAM_SAVE_FLAG_ZERO: