From mboxrd@z Thu Jan 1 00:00:00 1970 From: Will Deacon Subject: Re: [PATCH 08/18] arm/tlb: Convert to generic mmu_gather Date: Wed, 26 Sep 2018 13:54:06 +0100 Message-ID: <20180926125405.GH2979@brain-police> References: <20180926113623.863696043@infradead.org> <20180926114800.927066872@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20180926114800.927066872@infradead.org> Sender: linux-kernel-owner@vger.kernel.org To: Peter Zijlstra Cc: aneesh.kumar@linux.vnet.ibm.com, akpm@linux-foundation.org, npiggin@gmail.com, linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux@armlinux.org.uk, heiko.carstens@de.ibm.com, riel@surriel.com List-Id: linux-arch.vger.kernel.org On Wed, Sep 26, 2018 at 01:36:31PM +0200, Peter Zijlstra wrote: > Generic mmu_gather provides everything that ARM needs: > > - range tracking > - RCU table free > - VM_EXEC tracking > - VIPT cache flushing > > The one notable curiosity is the 'funny' range tracking for classical > ARM in __pte_free_tlb(). > > Cc: Nick Piggin > Cc: Andrew Morton > Cc: "Aneesh Kumar K.V" > Cc: Will Deacon > Cc: Russell King > Signed-off-by: Peter Zijlstra (Intel) > --- > arch/arm/include/asm/tlb.h | 255 ++------------------------------------------- > 1 file changed, 14 insertions(+), 241 deletions(-) [...] > static inline void > -tlb_remove_pmd_tlb_entry(struct mmu_gather *tlb, pmd_t *pmdp, unsigned long addr) > +__pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmdp, unsigned long addr) > { > - tlb_add_flush(tlb, addr); > -} > - > -#define pte_free_tlb(tlb, ptep, addr) __pte_free_tlb(tlb, ptep, addr) > -#define pmd_free_tlb(tlb, pmdp, addr) __pmd_free_tlb(tlb, pmdp, addr) > -#define pud_free_tlb(tlb, pudp, addr) pud_free((tlb)->mm, pudp) > - > -#define tlb_migrate_finish(mm) do { } while (0) > - > -static inline void tlb_change_page_size(struct mmu_gather *tlb, > - unsigned int page_size) > -{ > -} > - > -static inline void tlb_flush_remove_tables(struct mm_struct *mm) > -{ > -} > +#ifdef CONFIG_ARM_LPAE > + struct page *page = virt_to_page(pmdp); > > -static inline void tlb_flush_remove_tables_local(void *arg) > -{ > + pgtable_pmd_page_dtor(page); The dtor() is a NOP for Arm, so I don't think you need too call it (and we never call the ctor() afaict). I wonder if should be caring about this on arm64... Other than that: Acked-by: Will Deacon Will From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from foss.arm.com ([217.140.101.70]:45470 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726768AbeIZTHD (ORCPT ); Wed, 26 Sep 2018 15:07:03 -0400 Date: Wed, 26 Sep 2018 13:54:06 +0100 From: Will Deacon Subject: Re: [PATCH 08/18] arm/tlb: Convert to generic mmu_gather Message-ID: <20180926125405.GH2979@brain-police> References: <20180926113623.863696043@infradead.org> <20180926114800.927066872@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180926114800.927066872@infradead.org> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Peter Zijlstra Cc: aneesh.kumar@linux.vnet.ibm.com, akpm@linux-foundation.org, npiggin@gmail.com, linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux@armlinux.org.uk, heiko.carstens@de.ibm.com, riel@surriel.com Message-ID: <20180926125406.thkvLQPleiU9Jos5hqzi7PDJCT4A-YpWXXRVu1Ul3xg@z> On Wed, Sep 26, 2018 at 01:36:31PM +0200, Peter Zijlstra wrote: > Generic mmu_gather provides everything that ARM needs: > > - range tracking > - RCU table free > - VM_EXEC tracking > - VIPT cache flushing > > The one notable curiosity is the 'funny' range tracking for classical > ARM in __pte_free_tlb(). > > Cc: Nick Piggin > Cc: Andrew Morton > Cc: "Aneesh Kumar K.V" > Cc: Will Deacon > Cc: Russell King > Signed-off-by: Peter Zijlstra (Intel) > --- > arch/arm/include/asm/tlb.h | 255 ++------------------------------------------- > 1 file changed, 14 insertions(+), 241 deletions(-) [...] > static inline void > -tlb_remove_pmd_tlb_entry(struct mmu_gather *tlb, pmd_t *pmdp, unsigned long addr) > +__pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmdp, unsigned long addr) > { > - tlb_add_flush(tlb, addr); > -} > - > -#define pte_free_tlb(tlb, ptep, addr) __pte_free_tlb(tlb, ptep, addr) > -#define pmd_free_tlb(tlb, pmdp, addr) __pmd_free_tlb(tlb, pmdp, addr) > -#define pud_free_tlb(tlb, pudp, addr) pud_free((tlb)->mm, pudp) > - > -#define tlb_migrate_finish(mm) do { } while (0) > - > -static inline void tlb_change_page_size(struct mmu_gather *tlb, > - unsigned int page_size) > -{ > -} > - > -static inline void tlb_flush_remove_tables(struct mm_struct *mm) > -{ > -} > +#ifdef CONFIG_ARM_LPAE > + struct page *page = virt_to_page(pmdp); > > -static inline void tlb_flush_remove_tables_local(void *arg) > -{ > + pgtable_pmd_page_dtor(page); The dtor() is a NOP for Arm, so I don't think you need too call it (and we never call the ctor() afaict). I wonder if should be caring about this on arm64... Other than that: Acked-by: Will Deacon Will