From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EE0FDC433B4 for ; Mon, 3 May 2021 13:53:34 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6C0C2611CE for ; Mon, 3 May 2021 13:53:34 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6C0C2611CE Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.121621.229376 (Exim 4.92) (envelope-from ) id 1ldZ0i-0008EZ-NH; Mon, 03 May 2021 13:53:20 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 121621.229376; Mon, 03 May 2021 13:53:20 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1ldZ0i-0008ES-Ju; Mon, 03 May 2021 13:53:20 +0000 Received: by outflank-mailman (input) for mailman id 121621; Mon, 03 May 2021 13:53:19 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1ldZ0h-0008EN-EJ for xen-devel@lists.xenproject.org; Mon, 03 May 2021 13:53:19 +0000 Received: from mx2.suse.de (unknown [195.135.220.15]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id 0befd92a-be2d-4645-8de1-b1c785a63f61; Mon, 03 May 2021 13:53:18 +0000 (UTC) Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id A90DFB036; Mon, 3 May 2021 13:53:17 +0000 (UTC) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 0befd92a-be2d-4645-8de1-b1c785a63f61 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1620049997; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=AtyNzJXblg1TorskkTaOxOcwAAm/1XOy6DtVGC3zw+M=; b=kNW/dfUPLuB+hCowpK85ovdD8oU89MLMZWn8xCh+NgfvM9M5h1wpCtJOTM5ppMAxVitx+9 8DHYe73u2cMpHx53NL0h5Un0XrJLRpsYqDS5y+TY9Vq4kBuy755gtWpMZiq6O7LTPAU7MI D2xIKyEwJ8r+kleSZj7H/fkuu9JPf/U= Subject: Ping: [PATCH v2 8/8] Arm/optee: don't open-code xzalloc_flex_struct() From: Jan Beulich To: Volodymyr Babchuk Cc: George Dunlap , Julien Grall , Stefano Stabellini , "xen-devel@lists.xenproject.org" References: <091b4b91-712f-3526-78d1-80d31faf8e41@suse.com> <5fa042ac-9609-eab7-b14d-a59782ef4141@suse.com> Message-ID: Date: Mon, 3 May 2021 15:53:16 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.10.0 MIME-Version: 1.0 In-Reply-To: <5fa042ac-9609-eab7-b14d-a59782ef4141@suse.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Volodymyr, On 21.04.2021 16:59, Jan Beulich wrote: > The current use of xzalloc_bytes() in optee is nearly an open-coded > version of xzalloc_flex_struct(), which was introduced after the driver > was merged. > > The main difference is xzalloc_bytes() will also force the allocation to > be SMP_CACHE_BYTES aligned and therefore avoid sharing the cache line. > While sharing the cache line can have an impact on the performance, this > is also true for most of the other users of x*alloc(), x*alloc_array(), > and x*alloc_flex_struct(). So if we want to prevent sharing cache lines, > arranging for this should be done in the allocator itself. > > In this case, we don't need stricter alignment than what the allocator > provides. Hence replace the call to xzalloc_bytes() with one of > xzalloc_flex_struct(). > > Signed-off-by: Jan Beulich > Signed-off-by: Julien Grall > --- > v2: Use commit message very close to what was suggested by Julien. I realize I forgot to Cc you on the v2 submission, but I didn't hear back on v1 from you either. May I ask for an ack or otherwise? Thanks, Jan > --- a/xen/arch/arm/tee/optee.c > +++ b/xen/arch/arm/tee/optee.c > @@ -529,8 +529,7 @@ static struct optee_shm_buf *allocate_op > while ( unlikely(old != atomic_cmpxchg(&ctx->optee_shm_buf_pages, > old, new)) ); > > - optee_shm_buf = xzalloc_bytes(sizeof(struct optee_shm_buf) + > - pages_cnt * sizeof(struct page *)); > + optee_shm_buf = xzalloc_flex_struct(struct optee_shm_buf, pages, pages_cnt); > if ( !optee_shm_buf ) > { > err_code = -ENOMEM; > >