From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 16AAC42BFB for ; Fri, 22 Sep 2023 18:45:09 +0000 (UTC) Received: from mail-pl1-f169.google.com (mail-pl1-f169.google.com [209.85.214.169]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 05EF6AB; Fri, 22 Sep 2023 11:45:09 -0700 (PDT) Received: by mail-pl1-f169.google.com with SMTP id d9443c01a7336-1bf5c314a57so21419115ad.1; Fri, 22 Sep 2023 11:45:09 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695408308; x=1696013108; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=atbToeCfvaYcx4Wh/Dx61jMrCUFQT/qhHFCE0ode6Mo=; b=APSFFRDv4VBfuWYT7rhjPgpigYu8GvZw0OInTiCO62ALGNjCKEqMVtERbEAK1MozTY 1kTcUaIpoijDwClUgbOytwcJBFY4bYWZLfBe9DKV0MGge25Vvo/N6aqJH+CQyuH4n8pT hEdO+NlNsjg6Pn8pSgZUc+SfWyj97qTj4OES4OWychlgclOq9+P8n2R/O3Uezggkjwjr 0pKi3iHrvqNVglgQ0ByJcoqyALkd9WrI0roh3svEztftPGqu70ZGDaqnfsWJ0Nt+Yw7E Ye6yfNO9P/Ob5HT6+4DWT60Q+iZlMovJYM4FpB2jD70NBODEalnNR9HN9dLOu0to0RcG SGUw== X-Gm-Message-State: AOJu0YxgLh72yGDHAciBezE7gm18VfviYxZaIZ0QZEybfFuSthjWIggT ZOAN4UOat0s31SYlHy/amFbxu+CDh9w= X-Google-Smtp-Source: AGHT+IFkYaOsWjga65j1gAjNxQBP0tx3a13MykhAGrHKOBrBgEgFJTEqJ93NywNywSfCEXn7VNmDLQ== X-Received: by 2002:a17:903:41c3:b0:1c5:70d3:f193 with SMTP id u3-20020a17090341c300b001c570d3f193mr350824ple.10.1695408308401; Fri, 22 Sep 2023 11:45:08 -0700 (PDT) Received: from liuwe-devbox-debian-v2 ([20.69.120.36]) by smtp.gmail.com with ESMTPSA id iw11-20020a170903044b00b001c582de968dsm3832439plb.72.2023.09.22.11.45.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 22 Sep 2023 11:45:07 -0700 (PDT) Date: Fri, 22 Sep 2023 18:44:25 +0000 From: Wei Liu To: Dexuan Cui Cc: Olaf Hering , "linux-hyperv@vger.kernel.org" , "linux-arch@vger.kernel.org" , "linux-kernel@vger.kernel.org" , KY Srinivasan , Haiyang Zhang , Wei Liu , Arnd Bergmann Subject: Re: [PATCH v1] hyperv: reduce size of ms_hyperv_info Message-ID: References: <20230918160141.23465-1-olaf@aepfle.de> Precedence: bulk X-Mailing-List: linux-hyperv@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Spam-Status: No, score=-1.4 required=5.0 tests=BAYES_00, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS, RCVD_IN_DNSWL_BLOCKED,RCVD_IN_MSPIKE_H3,RCVD_IN_MSPIKE_WL, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net On Tue, Sep 19, 2023 at 06:18:53AM +0000, Dexuan Cui wrote: > > From: Olaf Hering > > Sent: Monday, September 18, 2023 9:02 AM > > [...] > > Use the hole prior shared_gpa_boundary to store the result of get_vtl. > > This reduces the size by 8 bytes. > > [...] > > --- a/include/asm-generic/mshyperv.h > > +++ b/include/asm-generic/mshyperv.h > > @@ -53,8 +53,8 @@ struct ms_hyperv_info { > > u32 reserved_b2 : 20; > > }; > > }; > > - u64 shared_gpa_boundary; > > u8 vtl; > > + u64 shared_gpa_boundary; > > }; > > extern struct ms_hyperv_info ms_hyperv; > > extern bool hv_nested; > > How about moving the 'vtl' field to an even earlier place: > > --- a/include/asm-generic/mshyperv.h > +++ b/include/asm-generic/mshyperv.h > @@ -36,6 +36,9 @@ struct ms_hyperv_info { > u32 nested_features; > u32 max_vp_index; > u32 max_lp_index; > + > + u8 vtl; > + > union { > u32 isolation_config_a; > struct { > @@ -54,7 +57,6 @@ struct ms_hyperv_info { > }; > }; > u64 shared_gpa_boundary; > - u8 vtl; > }; > extern struct ms_hyperv_info ms_hyperv; > extern bool hv_nested; > > This also reduces the size by 8 bytes, and keeps > the isolation_config_a/ isolation_config_b/ shared_gpa_boundary > together, which are related. Either method works for me. Will there be a v2 of this patch? Thanks, Wei.