From patchwork Tue Oct 17 08:29:53 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Juan Quintela X-Patchwork-Id: 13424765 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 D92A4CDB474 for ; Tue, 17 Oct 2023 08:36:29 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qsfUR-0006m4-RR; Tue, 17 Oct 2023 04:31:47 -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 1qsfUJ-0006Bt-6D for qemu-devel@nongnu.org; Tue, 17 Oct 2023 04:31:40 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qsfUH-0005TC-Qi for qemu-devel@nongnu.org; Tue, 17 Oct 2023 04:31:38 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1697531497; 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=B3yJFUYdqFQJsQYkBBr/IRkNfZqFDLAMp8HLpfQdXiI=; b=UDR2ug3N7RsFEw1HY4QrxCZfgNRQTsx6qgDCzk/hhv1NamyWchjjm9sNLt+ZNCJAsq6v4R x83bG36uPHRagSijc7qkuqnSPYUi78nR16O/6nTmfh1KiefsS/x1SsDKLnWFuGpvubatMo hJxwb4BlRyQ1OglQFkf6A0n2+NbsK/s= 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-466-USYYMvoPMJysEcDXI3xFWA-1; Tue, 17 Oct 2023 04:31:31 -0400 X-MC-Unique: USYYMvoPMJysEcDXI3xFWA-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 4D50F858280; Tue, 17 Oct 2023 08:31:31 +0000 (UTC) Received: from secure.mitica (unknown [10.39.194.127]) by smtp.corp.redhat.com (Postfix) with ESMTP id 995C21C060B0; Tue, 17 Oct 2023 08:31:28 +0000 (UTC) From: Juan Quintela To: qemu-devel@nongnu.org Cc: Eric Blake , Thomas Huth , Fabiano Rosas , Leonardo Bras , Vladimir Sementsov-Ogievskiy , Markus Armbruster , Peter Xu , Paolo Bonzini , Fam Zheng , Stefan Hajnoczi , Li Zhijian , John Snow , qemu-block@nongnu.org, Cleber Rosa , Juan Quintela , Laurent Vivier , Elena Ufimtseva Subject: [PULL 28/38] migration: check for rate_limit_max for RATE_LIMIT_DISABLED Date: Tue, 17 Oct 2023 10:29:53 +0200 Message-ID: <20231017083003.15951-29-quintela@redhat.com> In-Reply-To: <20231017083003.15951-1-quintela@redhat.com> References: <20231017083003.15951-1-quintela@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.7 Received-SPF: pass client-ip=170.10.133.124; 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_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable 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: Elena Ufimtseva In migration rate limiting atomic operations are used to read the rate limit variables and transferred bytes and they are expensive. Check first if rate_limit_max is equal to RATE_LIMIT_DISABLED and return false immediately if so. Note that with this patch we will also will stop flushing by not calling qemu_fflush() from migration_transferred_bytes() if the migration rate is not exceeded. This should be fine since migration thread calls in the loop migration_update_counters from migration_rate_limit() that calls the migration_transferred_bytes() and flushes there. Signed-off-by: Elena Ufimtseva Reviewed-by: Fabiano Rosas Reviewed-by: Peter Xu Reviewed-by: Juan Quintela Signed-off-by: Juan Quintela Message-ID: <20231011184358.97349-2-elena.ufimtseva@oracle.com> --- migration/migration-stats.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/migration/migration-stats.c b/migration/migration-stats.c index 84e11e6dd8..4cc989d975 100644 --- a/migration/migration-stats.c +++ b/migration/migration-stats.c @@ -24,14 +24,15 @@ bool migration_rate_exceeded(QEMUFile *f) return true; } + uint64_t rate_limit_max = migration_rate_get(); + if (rate_limit_max == RATE_LIMIT_DISABLED) { + return false; + } + uint64_t rate_limit_start = stat64_get(&mig_stats.rate_limit_start); uint64_t rate_limit_current = migration_transferred_bytes(f); uint64_t rate_limit_used = rate_limit_current - rate_limit_start; - uint64_t rate_limit_max = stat64_get(&mig_stats.rate_limit_max); - if (rate_limit_max == RATE_LIMIT_DISABLED) { - return false; - } if (rate_limit_max > 0 && rate_limit_used > rate_limit_max) { return true; }