From patchwork Wed Apr 17 17:58:14 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julien Grall X-Patchwork-Id: 10905729 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id DF7B2922 for ; Wed, 17 Apr 2019 18:00:15 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CB59D28B26 for ; Wed, 17 Apr 2019 18:00:15 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C02D328B80; Wed, 17 Apr 2019 18:00:15 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id B23DF28B26 for ; Wed, 17 Apr 2019 18:00:14 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1hGopL-0004DC-VT; Wed, 17 Apr 2019 17:58:31 +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 4.89) (envelope-from ) id 1hGopK-0004CA-Kw for xen-devel@lists.xenproject.org; Wed, 17 Apr 2019 17:58:30 +0000 X-Inumbo-ID: 68525f5a-613a-11e9-845b-c37828ef12d8 Received: from foss.arm.com (unknown [217.140.101.70]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTP id 68525f5a-613a-11e9-845b-c37828ef12d8; Wed, 17 Apr 2019 17:58:29 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5DAEF15AB; Wed, 17 Apr 2019 10:58:29 -0700 (PDT) Received: from e108454-lin.cambridge.arm.com (e108454-lin.cambridge.arm.com [10.1.196.50]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 4DCA43F59C; Wed, 17 Apr 2019 10:58:28 -0700 (PDT) From: Julien Grall To: xen-devel@lists.xenproject.org Date: Wed, 17 Apr 2019 18:58:14 +0100 Message-Id: <20190417175815.16905-7-julien.grall@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190417175815.16905-1-julien.grall@arm.com> References: <20190417175815.16905-1-julien.grall@arm.com> Subject: [Xen-devel] [PATCH 6/7] xen/arm: tlbflush: Rework TLB helpers 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: Oleksandr_Tyshchenko@epam.com, Julien Grall , sstabellini@kernel.org, Andrii_Anisov@epam.com MIME-Version: 1.0 Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" X-Virus-Scanned: ClamAV using ClamSMTP All the TLBs helpers invalidate all the TLB entries are using the same pattern: DSB SY TLBI ... DSB SY ISB This pattern is following pattern recommended by the Arm Arm to ensure visibility of updates to translation tables (see K10-5610 in ARM DDI 0487.A.k). We have been a bit too eager in Xen and use system-wide DSBs when this can be limited to the inner-shareable domain. Furthermore, the first DSB can be restrict further to only store in the inner-shareable domain. This is because the DSB is here to ensure visibility of the update to translation table walks. Lastly, there are a lack of documentation in most of the TLBs helper. Rather than trying to update the helpers one by one, this patch introduce a per-arch macro to generate the TLB helpers. This will be easier to update the TLBs helper in the future and the documentation. Signed-off-by: Julien Grall Reviewed-by: Andrii Anisov --- xen/include/asm-arm/arm32/flushtlb.h | 73 ++++++++++++++-------------------- xen/include/asm-arm/arm64/flushtlb.h | 76 +++++++++++++++--------------------- 2 files changed, 60 insertions(+), 89 deletions(-) diff --git a/xen/include/asm-arm/arm32/flushtlb.h b/xen/include/asm-arm/arm32/flushtlb.h index b629db61cb..9085e65011 100644 --- a/xen/include/asm-arm/arm32/flushtlb.h +++ b/xen/include/asm-arm/arm32/flushtlb.h @@ -1,59 +1,44 @@ #ifndef __ASM_ARM_ARM32_FLUSHTLB_H__ #define __ASM_ARM_ARM32_FLUSHTLB_H__ -/* Flush local TLBs, current VMID only */ -static inline void flush_guest_tlb_local(void) -{ - dsb(sy); - - WRITE_CP32((uint32_t) 0, TLBIALL); - - dsb(sy); - isb(); +/* + * Every invalidation operation use the following patterns: + * + * DSB ISHST // Ensure prior page-tables updates have completed + * TLBI... // Invalidate the TLB + * DSB ISH // Ensure the TLB invalidation has completed + * ISB // See explanation below + * + * For Xen page-tables the ISB will discard any instructions fetched + * from the old mappings. + * + * For the Stage-2 page-tables the ISB ensures the completion of the DSB + * (and therefore the TLB invalidation) before continuing. So we know + * the TLBs cannot contain an entry for a mapping we may have removed. + */ +#define TLB_HELPER(name, tlbop) \ +static inline void name(void) \ +{ \ + dsb(ishst); \ + WRITE_CP32(0, tlbop); \ + dsb(ish); \ + isb(); \ } -/* Flush inner shareable TLBs, current VMID only */ -static inline void flush_guest_tlb(void) -{ - dsb(sy); - - WRITE_CP32((uint32_t) 0, TLBIALLIS); +/* Flush local TLBs, current VMID only */ +TLB_HELPER(flush_guest_tlb_local, TLBIALL); - dsb(sy); - isb(); -} +/* Flush inner shareable TLBs, current VMID only */ +TLB_HELPER(flush_guest_tlb, TLBIALLIS); /* Flush local TLBs, all VMIDs, non-hypervisor mode */ -static inline void flush_all_guests_tlb_local(void) -{ - dsb(sy); - - WRITE_CP32((uint32_t) 0, TLBIALLNSNH); - - dsb(sy); - isb(); -} +TLB_HELPER(flush_all_guests_tlb_local, TLBIALLNSNH); /* Flush innershareable TLBs, all VMIDs, non-hypervisor mode */ -static inline void flush_all_guests_tlb(void) -{ - dsb(sy); - - WRITE_CP32((uint32_t) 0, TLBIALLNSNHIS); - - dsb(sy); - isb(); -} +TLB_HELPER(flush_all_guests_tlb, TLBIALLNSNHIS); /* Flush all hypervisor mappings from the TLB of the local processor. */ -static inline void flush_xen_tlb_local(void) -{ - asm volatile("dsb;" /* Ensure preceding are visible */ - CMD_CP32(TLBIALLH) - "dsb;" /* Ensure completion of the TLB flush */ - "isb;" - : : : "memory"); -} +TLB_HELPER(flush_xen_tlb_local, TLBIALLH); /* Flush TLB of local processor for address va. */ static inline void __flush_xen_tlb_one_local(vaddr_t va) diff --git a/xen/include/asm-arm/arm64/flushtlb.h b/xen/include/asm-arm/arm64/flushtlb.h index 2fed34b2ec..ceec59542e 100644 --- a/xen/include/asm-arm/arm64/flushtlb.h +++ b/xen/include/asm-arm/arm64/flushtlb.h @@ -1,60 +1,46 @@ #ifndef __ASM_ARM_ARM64_FLUSHTLB_H__ #define __ASM_ARM_ARM64_FLUSHTLB_H__ -/* Flush local TLBs, current VMID only */ -static inline void flush_guest_tlb_local(void) -{ - asm volatile( - "dsb sy;" - "tlbi vmalls12e1;" - "dsb sy;" - "isb;" - : : : "memory"); +/* + * Every invalidation operation use the following patterns: + * + * DSB ISHST // Ensure prior page-tables updates have completed + * TLBI... // Invalidate the TLB + * DSB ISH // Ensure the TLB invalidation has completed + * ISB // See explanation below + * + * For Xen page-tables the ISB will discard any instructions fetched + * from the old mappings. + * + * For the Stage-2 page-tables the ISB ensures the completion of the DSB + * (and therefore the TLB invalidation) before continuing. So we know + * the TLBs cannot contain an entry for a mapping we may have removed. + */ +#define TLB_HELPER(name, tlbop) \ +static inline void name(void) \ +{ \ + asm volatile( \ + "dsb ishst;" \ + "tlbi " # tlbop ";" \ + "dsb ish;" \ + "isb;" \ + : : : "memory"); \ } +/* Flush local TLBs, current VMID only. */ +TLB_HELPER(flush_guest_tlb_local, vmalls12e1); + /* Flush innershareable TLBs, current VMID only */ -static inline void flush_guest_tlb(void) -{ - asm volatile( - "dsb sy;" - "tlbi vmalls12e1is;" - "dsb sy;" - "isb;" - : : : "memory"); -} +TLB_HELPER(flush_guest_tlb, vmalls12e1is); /* Flush local TLBs, all VMIDs, non-hypervisor mode */ -static inline void flush_all_guests_tlb_local(void) -{ - asm volatile( - "dsb sy;" - "tlbi alle1;" - "dsb sy;" - "isb;" - : : : "memory"); -} +TLB_HELPER(flush_all_guests_tlb_local, alle1); /* Flush innershareable TLBs, all VMIDs, non-hypervisor mode */ -static inline void flush_all_guests_tlb(void) -{ - asm volatile( - "dsb sy;" - "tlbi alle1is;" - "dsb sy;" - "isb;" - : : : "memory"); -} +TLB_HELPER(flush_all_guests_tlb, alle1is); /* Flush all hypervisor mappings from the TLB of the local processor. */ -static inline void flush_xen_tlb_local(void) -{ - asm volatile ( - "dsb sy;" /* Ensure visibility of PTE writes */ - "tlbi alle2;" /* Flush hypervisor TLB */ - "dsb sy;" /* Ensure completion of TLB flush */ - "isb;" - : : : "memory"); -} +TLB_HELPER(flush_xen_tlb_local, alle2); /* Flush TLB of local processor for address va. */ static inline void __flush_xen_tlb_one_local(vaddr_t va)