From patchwork Wed Sep 4 12:44:15 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fabiano Rosas X-Patchwork-Id: 1980775 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=suse.de header.i=@suse.de header.a=rsa-sha256 header.s=susede2_rsa header.b=zxUkvX/Z; dkim=pass header.d=suse.de header.i=@suse.de header.a=ed25519-sha256 header.s=susede2_ed25519 header.b=5UdEBBjI; dkim=pass (1024-bit key) header.d=suse.de header.i=@suse.de header.a=rsa-sha256 header.s=susede2_rsa header.b=zxUkvX/Z; dkim=neutral header.d=suse.de header.i=@suse.de header.a=ed25519-sha256 header.s=susede2_ed25519 header.b=5UdEBBjI; dkim-atps=neutral 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=patchwork.ozlabs.org) 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 4WzMjr7243z1yg3 for ; Wed, 4 Sep 2024 22:48:32 +1000 (AEST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1slpP8-00036Q-Sc; Wed, 04 Sep 2024 08:46:34 -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 1slpNw-0006i6-6d for qemu-devel@nongnu.org; Wed, 04 Sep 2024 08:45:22 -0400 Received: from smtp-out2.suse.de ([195.135.223.131]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1slpNt-0005u0-98 for qemu-devel@nongnu.org; Wed, 04 Sep 2024 08:45:19 -0400 Received: from imap1.dmz-prg2.suse.org (unknown [10.150.64.97]) (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 smtp-out2.suse.de (Postfix) with ESMTPS id C8A4C1F38E; Wed, 4 Sep 2024 12:45:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1725453915; 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=MNzb/EaSJ6kInfzVq5bNLBikfqN947TiDCwvTjFUn1o=; b=zxUkvX/ZGQzOvw3FzHPsZErWa6IS5xnIagWG1zZa6MW1VW60CVQi3lbS5kvC1a2cyECkS9 yS32UK2u7XWjAfF179adPT0JwPYYG7Yty199q4jI+YTPbP1dM5wFsG3LuPZ1ezaEIoZZ+D n9l7zTRcaWG6kwDPsVpBEyNZQ87UuCY= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1725453915; 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=MNzb/EaSJ6kInfzVq5bNLBikfqN947TiDCwvTjFUn1o=; b=5UdEBBjIR1gMAYoPFRsF/+2LhbzmILSoBkAIbPBRqs0uudfGd7EIw4VA4cD33Rq2Tn7voj wDQQLhcyUTPdTjBQ== Authentication-Results: smtp-out2.suse.de; none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1725453915; 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=MNzb/EaSJ6kInfzVq5bNLBikfqN947TiDCwvTjFUn1o=; b=zxUkvX/ZGQzOvw3FzHPsZErWa6IS5xnIagWG1zZa6MW1VW60CVQi3lbS5kvC1a2cyECkS9 yS32UK2u7XWjAfF179adPT0JwPYYG7Yty199q4jI+YTPbP1dM5wFsG3LuPZ1ezaEIoZZ+D n9l7zTRcaWG6kwDPsVpBEyNZQ87UuCY= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1725453915; 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=MNzb/EaSJ6kInfzVq5bNLBikfqN947TiDCwvTjFUn1o=; b=5UdEBBjIR1gMAYoPFRsF/+2LhbzmILSoBkAIbPBRqs0uudfGd7EIw4VA4cD33Rq2Tn7voj wDQQLhcyUTPdTjBQ== Received: from imap1.dmz-prg2.suse.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 imap1.dmz-prg2.suse.org (Postfix) with ESMTPS id A27EA139D2; Wed, 4 Sep 2024 12:45:14 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id QG8nGlpW2GZuVQAAD6G6ig (envelope-from ); Wed, 04 Sep 2024 12:45:14 +0000 From: Fabiano Rosas To: qemu-devel@nongnu.org Cc: Peter Xu , Richard Henderson Subject: [PULL 32/34] migration/multifd: Add documentation for multifd methods Date: Wed, 4 Sep 2024 09:44:15 -0300 Message-Id: <20240904124417.14565-33-farosas@suse.de> X-Mailer: git-send-email 2.35.3 In-Reply-To: <20240904124417.14565-1-farosas@suse.de> References: <20240904124417.14565-1-farosas@suse.de> MIME-Version: 1.0 X-Spam-Score: -2.79 X-Spamd-Result: default: False [-2.79 / 50.00]; BAYES_HAM(-3.00)[100.00%]; MID_CONTAINS_FROM(1.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; R_MISSING_CHARSET(0.50)[]; NEURAL_HAM_SHORT(-0.19)[-0.934]; MIME_GOOD(-0.10)[text/plain]; MIME_TRACE(0.00)[0:+]; TO_DN_SOME(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; ARC_NA(0.00)[]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; FUZZY_BLOCKED(0.00)[rspamd.com]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_THREE(0.00)[3]; RCVD_COUNT_TWO(0.00)[2]; TO_MATCH_ENVRCPT_ALL(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:mid,suse.de:email]; RCVD_TLS_ALL(0.00)[] Received-SPF: pass client-ip=195.135.223.131; envelope-from=farosas@suse.de; helo=smtp-out2.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, T_SCC_BODY_TEXT_LINE=-0.01 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Add documentation clarifying the usage of the multifd methods. The general idea is that the client code calls into multifd to trigger send/recv of data and multifd then calls these hooks back from the worker threads at opportune moments so the client can process a portion of the data. Suggested-by: Peter Xu Reviewed-by: Peter Xu Signed-off-by: Fabiano Rosas --- migration/multifd.h | 76 +++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 70 insertions(+), 6 deletions(-) diff --git a/migration/multifd.h b/migration/multifd.h index 13e7a88c01..3bb96e9558 100644 --- a/migration/multifd.h +++ b/migration/multifd.h @@ -229,17 +229,81 @@ typedef struct { } MultiFDRecvParams; typedef struct { - /* Setup for sending side */ + /* + * The send_setup, send_cleanup, send_prepare are only called on + * the QEMU instance at the migration source. + */ + + /* + * Setup for sending side. Called once per channel during channel + * setup phase. + * + * Must allocate p->iov. If packets are in use (default), one + * extra iovec must be allocated for the packet header. Any memory + * allocated in this hook must be released at send_cleanup. + * + * p->write_flags may be used for passing flags to the QIOChannel. + * + * p->compression_data may be used by compression methods to store + * compression data. + */ int (*send_setup)(MultiFDSendParams *p, Error **errp); - /* Cleanup for sending side */ + + /* + * Cleanup for sending side. Called once per channel during + * channel cleanup phase. + */ void (*send_cleanup)(MultiFDSendParams *p, Error **errp); - /* Prepare the send packet */ + + /* + * Prepare the send packet. Called as a result of multifd_send() + * on the client side, with p pointing to the MultiFDSendParams of + * a channel that is currently idle. + * + * Must populate p->iov with the data to be sent, increment + * p->iovs_num to match the amount of iovecs used and set + * p->next_packet_size with the amount of data currently present + * in p->iov. + * + * Must indicate whether this is a compression packet by setting + * p->flags. + * + * As a last step, if packets are in use (default), must prepare + * the packet by calling multifd_send_fill_packet(). + */ int (*send_prepare)(MultiFDSendParams *p, Error **errp); - /* Setup for receiving side */ + + /* + * The recv_setup, recv_cleanup, recv are only called on the QEMU + * instance at the migration destination. + */ + + /* + * Setup for receiving side. Called once per channel during + * channel setup phase. May be empty. + * + * May allocate data structures for the receiving of data. May use + * p->iov. Compression methods may use p->compress_data. + */ int (*recv_setup)(MultiFDRecvParams *p, Error **errp); - /* Cleanup for receiving side */ + + /* + * Cleanup for receiving side. Called once per channel during + * channel cleanup phase. May be empty. + */ void (*recv_cleanup)(MultiFDRecvParams *p); - /* Read all data */ + + /* + * Data receive method. Called as a result of multifd_recv() on + * the client side, with p pointing to the MultiFDRecvParams of a + * channel that is currently idle. Only called if there is data + * available to receive. + * + * Must validate p->flags according to what was set at + * send_prepare. + * + * Must read the data from the QIOChannel p->c. + */ int (*recv)(MultiFDRecvParams *p, Error **errp); } MultiFDMethods;