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X-CSE-ConnectionGUID: p1GeMIaCQ2i1ijVTcIfZyQ== X-CSE-MsgGUID: tWYdhAfKQQaUyM6hx0XqVw== X-IronPort-AV: E=McAfee;i="6700,10204,11254"; a="30722538" X-IronPort-AV: E=Sophos;i="6.12,149,1728975600"; d="scan'208";a="30722538" Received: from fmviesa008.fm.intel.com ([10.60.135.148]) by fmvoesa112.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Nov 2024 16:20:21 -0800 X-CSE-ConnectionGUID: lCJuHIFDQ56vdpWT52eddw== X-CSE-MsgGUID: 7n8fioSORDCteWdnd3uKOg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.12,149,1728975600"; d="scan'208";a="87815919" Received: from jairdeje-mobl1.amr.corp.intel.com (HELO [10.124.220.61]) ([10.124.220.61]) by fmviesa008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Nov 2024 16:20:20 -0800 Message-ID: Date: Tue, 12 Nov 2024 16:20:19 -0800 Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 08/25] x86/virt/tdx: Add SEAMCALL wrappers for TDX page cache management To: Rick Edgecombe , pbonzini@redhat.com, seanjc@google.com Cc: yan.y.zhao@intel.com, isaku.yamahata@gmail.com, kai.huang@intel.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, tony.lindgren@linux.intel.com, xiaoyao.li@intel.com, reinette.chatre@intel.com, Isaku Yamahata , Sean Christopherson , Binbin Wu , Yuan Yao References: <20241030190039.77971-1-rick.p.edgecombe@intel.com> <20241030190039.77971-9-rick.p.edgecombe@intel.com> From: Dave Hansen Content-Language: en-US Autocrypt: addr=dave.hansen@intel.com; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 10/30/24 12:00, Rick Edgecombe wrote: > +u64 tdh_phymem_page_reclaim(u64 page, u64 *rcx, u64 *rdx, u64 *r8) > +{ > + struct tdx_module_args args = { > + .rcx = page, > + }; > + u64 ret; This isn't quite what I'm looking for in these wrappers. For instance: > + /* > + * Additional error information: > + * > + * - RCX: page type > + * - RDX: owner > + * - R8: page size (4K, 2M or 1G) > + */ > + *rcx = args.rcx; > + *rdx = args.rdx; > + *r8 = args.r8; If this were, instead: u64 tdh_phymem_page_reclaim(u64 page, u64 *type, u64 *owner, u64 *size) { ... *type = args.rcx; *owner = args.rdx; *size = args.r8; Then you wouldn't need the comment in the first place. Then you could also be thinking about adding _some_ kind of type safety to the arguments. The 'size' or the 'type' could totally be enums. There's really zero value in having wrappers like these. They don't have any type safety or add any readability or make the seamcall easier to use. There's almost no value in having these versus just exporting seamcall_ret() itself.