From patchwork Wed Sep 25 15:48:52 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tamas K Lengyel X-Patchwork-Id: 11160999 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D3957924 for ; Wed, 25 Sep 2019 15:51:34 +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 B93BB21D7A for ; Wed, 25 Sep 2019 15:51:34 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B93BB21D7A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1iD9Yh-00027m-Il; Wed, 25 Sep 2019 15:50:27 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1iD9Yg-00026y-Nt for xen-devel@lists.xenproject.org; Wed, 25 Sep 2019 15:50:26 +0000 X-Inumbo-ID: 13f17c02-dfac-11e9-bf31-bc764e2007e4 Received: from mga12.intel.com (unknown [192.55.52.136]) by localhost (Halon) with ESMTPS id 13f17c02-dfac-11e9-bf31-bc764e2007e4; Wed, 25 Sep 2019 15:49:37 +0000 (UTC) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 25 Sep 2019 08:49:37 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,548,1559545200"; d="scan'208";a="193812693" Received: from tlengyel-mobl2.amr.corp.intel.com (HELO localhost.localdomain) ([10.252.129.153]) by orsmga006.jf.intel.com with ESMTP; 25 Sep 2019 08:49:36 -0700 From: Tamas K Lengyel To: xen-devel@lists.xenproject.org Date: Wed, 25 Sep 2019 08:48:52 -0700 Message-Id: <31f87866d0f24657ce12e6ca32c8a552639cb34d.1569425745.git.tamas.lengyel@intel.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: References: MIME-Version: 1.0 Subject: [Xen-devel] [RFC PATCH for-next 14/18] x86/mem_sharing: Enable mem_sharing on first memop X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Tamas K Lengyel , Tamas K Lengyel , Wei Liu , George Dunlap , Andrew Cooper , Jan Beulich , =?utf-8?q?Roger_Pau_Monn=C3=A9?= Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" It is wasteful to require separate hypercalls to enable sharing on both the parent and the client domain during VM forking. To speed things up we enable sharing on the first memop in case it wasn't already enabled. Signed-off-by: Tamas K Lengyel --- xen/arch/x86/mm/mem_sharing.c | 39 +++++++++++++++++++++-------------- 1 file changed, 23 insertions(+), 16 deletions(-) diff --git a/xen/arch/x86/mm/mem_sharing.c b/xen/arch/x86/mm/mem_sharing.c index 99f24fcf6c..65aa64be99 100644 --- a/xen/arch/x86/mm/mem_sharing.c +++ b/xen/arch/x86/mm/mem_sharing.c @@ -1402,6 +1402,24 @@ static int range_share(struct domain *d, struct domain *cd, return rc; } +static inline int mem_sharing_control(struct domain *d, bool enable) +{ + if ( enable ) + { + if ( unlikely(!is_hvm_domain(d)) ) + return -ENOSYS; + + if ( unlikely(!hap_enabled(d)) ) + return -ENODEV; + + if ( unlikely(has_iommu_pt(d)) ) + return -EXDEV; + } + + d->arch.hvm.mem_sharing.enabled = enable; + return 0; +} + int mem_sharing_memop(XEN_GUEST_HANDLE_PARAM(xen_mem_sharing_op_t) arg) { int rc; @@ -1423,10 +1441,8 @@ int mem_sharing_memop(XEN_GUEST_HANDLE_PARAM(xen_mem_sharing_op_t) arg) if ( rc ) goto out; - /* Only HAP is supported */ - rc = -ENODEV; - if ( !mem_sharing_enabled(d) ) - goto out; + if ( !mem_sharing_enabled(d) && (rc = mem_sharing_control(d, true)) ) + return rc; switch ( mso.op ) { @@ -1675,24 +1691,15 @@ int mem_sharing_domctl(struct domain *d, struct xen_domctl_mem_sharing_op *mec) { int rc; - /* Only HAP is supported */ - if ( !hap_enabled(d) ) - return -ENODEV; - switch(mec->op) { case XEN_DOMCTL_MEM_SHARING_CONTROL: - { - rc = 0; - if ( unlikely(has_iommu_pt(d) && mec->u.enable) ) - rc = -EXDEV; - else - d->arch.hvm.mem_sharing.enabled = mec->u.enable; - } - break; + rc = mem_sharing_control(d, mec->u.enable); + break; default: rc = -ENOSYS; + break; } return rc;