From patchwork Mon Dec 19 15:35:35 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Zijlstra X-Patchwork-Id: 13076748 X-Patchwork-Delegate: herbert@gondor.apana.org.au 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CD609C3DA71 for ; Mon, 19 Dec 2022 15:46:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232733AbiLSPqF (ORCPT ); Mon, 19 Dec 2022 10:46:05 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60120 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232614AbiLSPpa (ORCPT ); Mon, 19 Dec 2022 10:45:30 -0500 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C989713D3E; Mon, 19 Dec 2022 07:44:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Content-Type:MIME-Version:References: Subject:Cc:To:From:Date:Message-ID:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To; bh=3ubHXmjMHuO7YFbxrF9R90Y+YVnse9xBuEbHAitlUas=; b=F9Ye6OWUV85f2WpS6IBk1wtws0 OTuNbel0nmECFfo9vSobT5XqJjrd1NXNjVMTobisn4/wA+8YgSgS7EtkQgHrAwNk1mzCZoQWEr3DB NTpTBmvMROo2VE532Wumfb7uJRZrPtV/7FYH/qfCQcjhVKH324Z+UDiF9oUlSfMVRt4iju5/8ArAS oNE9X81K/IL3HQ2NXfx5yaqnUun4rlkKYw90gPjppR/qSPzQkePxvogKLcJyO5OlHCMntGMJy8R8z JvgmFlxxAvis2uvoGT8nU6uoOYzNtGmE8G6pBQ/Ix09BE8EcxzFV4f9LTZAQgindGBBIcL4SyC3j3 zgVgdFyg==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.96 #2 (Red Hat Linux)) id 1p7IIJ-00CeDs-0v; Mon, 19 Dec 2022 15:43:11 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 15D99303386; Mon, 19 Dec 2022 16:43:10 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id 9EA1420B0F89F; Mon, 19 Dec 2022 16:43:06 +0100 (CET) Message-ID: <20221219154119.484857499@infradead.org> User-Agent: quilt/0.66 Date: Mon, 19 Dec 2022 16:35:35 +0100 From: Peter Zijlstra To: torvalds@linux-foundation.org Cc: corbet@lwn.net, will@kernel.org, peterz@infradead.org, boqun.feng@gmail.com, mark.rutland@arm.com, catalin.marinas@arm.com, dennis@kernel.org, tj@kernel.org, cl@linux.com, hca@linux.ibm.com, gor@linux.ibm.com, agordeev@linux.ibm.com, borntraeger@linux.ibm.com, svens@linux.ibm.com, Herbert Xu , davem@davemloft.net, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, joro@8bytes.org, suravee.suthikulpanit@amd.com, robin.murphy@arm.com, dwmw2@infradead.org, baolu.lu@linux.intel.com, Arnd Bergmann , penberg@kernel.org, rientjes@google.com, iamjoonsoo.kim@lge.com, Andrew Morton , vbabka@suse.cz, roman.gushchin@linux.dev, 42.hyeyoo@gmail.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-s390@vger.kernel.org, linux-crypto@vger.kernel.org, iommu@lists.linux.dev, linux-arch@vger.kernel.org Subject: [RFC][PATCH 10/12] x86,intel_iommu: Replace cmpxchg_double() References: <20221219153525.632521981@infradead.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org Signed-off-by: Peter Zijlstra (Intel) --- drivers/iommu/intel/irq_remapping.c | 8 -- include/linux/dmar.h | 125 +++++++++++++++++++----------------- 2 files changed, 68 insertions(+), 65 deletions(-) --- a/drivers/iommu/intel/irq_remapping.c +++ b/drivers/iommu/intel/irq_remapping.c @@ -174,18 +174,14 @@ static int modify_irte(struct irq_2_iomm irte = &iommu->ir_table->base[index]; if ((irte->pst == 1) || (irte_modified->pst == 1)) { - bool ret; - - ret = cmpxchg_double(&irte->low, &irte->high, - irte->low, irte->high, - irte_modified->low, irte_modified->high); /* * We use cmpxchg16 to atomically update the 128-bit IRTE, * and it cannot be updated by the hardware or other processors * behind us, so the return value of cmpxchg16 should be the * same as the old value. */ - WARN_ON(!ret); + u128 old = irte->irte; + WARN_ON(!try_cmpxchg128(&irte->irte, &old, irte_modified->irte)); } else { WRITE_ONCE(irte->low, irte_modified->low); WRITE_ONCE(irte->high, irte_modified->high); --- a/include/linux/dmar.h +++ b/include/linux/dmar.h @@ -201,67 +201,74 @@ static inline void detect_intel_iommu(vo struct irte { union { - /* Shared between remapped and posted mode*/ struct { - __u64 present : 1, /* 0 */ - fpd : 1, /* 1 */ - __res0 : 6, /* 2 - 6 */ - avail : 4, /* 8 - 11 */ - __res1 : 3, /* 12 - 14 */ - pst : 1, /* 15 */ - vector : 8, /* 16 - 23 */ - __res2 : 40; /* 24 - 63 */ + union { + /* Shared between remapped and posted mode*/ + struct { + __u64 present : 1, /* 0 */ + fpd : 1, /* 1 */ + __res0 : 6, /* 2 - 6 */ + avail : 4, /* 8 - 11 */ + __res1 : 3, /* 12 - 14 */ + pst : 1, /* 15 */ + vector : 8, /* 16 - 23 */ + __res2 : 40; /* 24 - 63 */ + }; + + /* Remapped mode */ + struct { + __u64 r_present : 1, /* 0 */ + r_fpd : 1, /* 1 */ + dst_mode : 1, /* 2 */ + redir_hint : 1, /* 3 */ + trigger_mode : 1, /* 4 */ + dlvry_mode : 3, /* 5 - 7 */ + r_avail : 4, /* 8 - 11 */ + r_res0 : 4, /* 12 - 15 */ + r_vector : 8, /* 16 - 23 */ + r_res1 : 8, /* 24 - 31 */ + dest_id : 32; /* 32 - 63 */ + }; + + /* Posted mode */ + struct { + __u64 p_present : 1, /* 0 */ + p_fpd : 1, /* 1 */ + p_res0 : 6, /* 2 - 7 */ + p_avail : 4, /* 8 - 11 */ + p_res1 : 2, /* 12 - 13 */ + p_urgent : 1, /* 14 */ + p_pst : 1, /* 15 */ + p_vector : 8, /* 16 - 23 */ + p_res2 : 14, /* 24 - 37 */ + pda_l : 26; /* 38 - 63 */ + }; + __u64 low; + }; + + union { + /* Shared between remapped and posted mode*/ + struct { + __u64 sid : 16, /* 64 - 79 */ + sq : 2, /* 80 - 81 */ + svt : 2, /* 82 - 83 */ + __res3 : 44; /* 84 - 127 */ + }; + + /* Posted mode*/ + struct { + __u64 p_sid : 16, /* 64 - 79 */ + p_sq : 2, /* 80 - 81 */ + p_svt : 2, /* 82 - 83 */ + p_res3 : 12, /* 84 - 95 */ + pda_h : 32; /* 96 - 127 */ + }; + __u64 high; + }; }; - - /* Remapped mode */ - struct { - __u64 r_present : 1, /* 0 */ - r_fpd : 1, /* 1 */ - dst_mode : 1, /* 2 */ - redir_hint : 1, /* 3 */ - trigger_mode : 1, /* 4 */ - dlvry_mode : 3, /* 5 - 7 */ - r_avail : 4, /* 8 - 11 */ - r_res0 : 4, /* 12 - 15 */ - r_vector : 8, /* 16 - 23 */ - r_res1 : 8, /* 24 - 31 */ - dest_id : 32; /* 32 - 63 */ - }; - - /* Posted mode */ - struct { - __u64 p_present : 1, /* 0 */ - p_fpd : 1, /* 1 */ - p_res0 : 6, /* 2 - 7 */ - p_avail : 4, /* 8 - 11 */ - p_res1 : 2, /* 12 - 13 */ - p_urgent : 1, /* 14 */ - p_pst : 1, /* 15 */ - p_vector : 8, /* 16 - 23 */ - p_res2 : 14, /* 24 - 37 */ - pda_l : 26; /* 38 - 63 */ - }; - __u64 low; - }; - - union { - /* Shared between remapped and posted mode*/ - struct { - __u64 sid : 16, /* 64 - 79 */ - sq : 2, /* 80 - 81 */ - svt : 2, /* 82 - 83 */ - __res3 : 44; /* 84 - 127 */ - }; - - /* Posted mode*/ - struct { - __u64 p_sid : 16, /* 64 - 79 */ - p_sq : 2, /* 80 - 81 */ - p_svt : 2, /* 82 - 83 */ - p_res3 : 12, /* 84 - 95 */ - pda_h : 32; /* 96 - 127 */ - }; - __u64 high; +#ifdef CONFIG_IRQ_REMAP + __u128 irte; +#endif }; };