From patchwork Thu Aug 9 15:03:01 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kirill A . Shutemov" X-Patchwork-Id: 1301301 Return-Path: X-Original-To: patchwork-linux-sh@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id 32CFFDFF7B for ; Thu, 9 Aug 2012 15:04:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030981Ab2HIPDi (ORCPT ); Thu, 9 Aug 2012 11:03:38 -0400 Received: from mga01.intel.com ([192.55.52.88]:21172 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030978Ab2HIPDg (ORCPT ); Thu, 9 Aug 2012 11:03:36 -0400 Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga101.fm.intel.com with ESMTP; 09 Aug 2012 08:03:17 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.77,740,1336374000"; d="scan'208";a="205532849" Received: from blue.fi.intel.com ([10.237.72.50]) by fmsmga002.fm.intel.com with ESMTP; 09 Aug 2012 08:03:11 -0700 Received: by blue.fi.intel.com (Postfix, from userid 1000) id B897BE0085; Thu, 9 Aug 2012 18:03:14 +0300 (EEST) From: "Kirill A. Shutemov" To: linux-mm@kvack.org Cc: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, Andi Kleen , "Kirill A. Shutemov" , Tim Chen , Alex Shi , Jan Beulich , Robert Richter , Andy Lutomirski , Andrew Morton , Andrea Arcangeli , Johannes Weiner , Hugh Dickins , KAMEZAWA Hiroyuki , Mel Gorman , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-mips@linux-mips.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org Subject: [PATCH v2 4/6] x86: Add clear_page_nocache Date: Thu, 9 Aug 2012 18:03:01 +0300 Message-Id: <1344524583-1096-5-git-send-email-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1344524583-1096-1-git-send-email-kirill.shutemov@linux.intel.com> References: <1344524583-1096-1-git-send-email-kirill.shutemov@linux.intel.com> Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org From: Andi Kleen Add a cache avoiding version of clear_page. Straight forward integer variant of the existing 64bit clear_page, for both 32bit and 64bit. Also add the necessary glue for highmem including a layer that non cache coherent architectures that use the virtual address for flushing can hook in. This is not needed on x86 of course. If an architecture wants to provide cache avoiding version of clear_page it should to define ARCH_HAS_USER_NOCACHE to 1 and implement clear_page_nocache() and clear_user_highpage_nocache(). Signed-off-by: Andi Kleen Signed-off-by: Kirill A. Shutemov --- arch/x86/include/asm/page.h | 2 ++ arch/x86/include/asm/string_32.h | 5 +++++ arch/x86/include/asm/string_64.h | 5 +++++ arch/x86/lib/Makefile | 1 + arch/x86/lib/clear_page_nocache_32.S | 30 ++++++++++++++++++++++++++++++ arch/x86/lib/clear_page_nocache_64.S | 29 +++++++++++++++++++++++++++++ arch/x86/mm/fault.c | 7 +++++++ 7 files changed, 79 insertions(+), 0 deletions(-) create mode 100644 arch/x86/lib/clear_page_nocache_32.S create mode 100644 arch/x86/lib/clear_page_nocache_64.S diff --git a/arch/x86/include/asm/page.h b/arch/x86/include/asm/page.h index 8ca8283..aa83a1b 100644 --- a/arch/x86/include/asm/page.h +++ b/arch/x86/include/asm/page.h @@ -29,6 +29,8 @@ static inline void copy_user_page(void *to, void *from, unsigned long vaddr, copy_page(to, from); } +void clear_user_highpage_nocache(struct page *page, unsigned long vaddr); + #define __alloc_zeroed_user_highpage(movableflags, vma, vaddr) \ alloc_page_vma(GFP_HIGHUSER | __GFP_ZERO | movableflags, vma, vaddr) #define __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE diff --git a/arch/x86/include/asm/string_32.h b/arch/x86/include/asm/string_32.h index 3d3e835..3f2fbcf 100644 --- a/arch/x86/include/asm/string_32.h +++ b/arch/x86/include/asm/string_32.h @@ -3,6 +3,8 @@ #ifdef __KERNEL__ +#include + /* Let gcc decide whether to inline or use the out of line functions */ #define __HAVE_ARCH_STRCPY @@ -337,6 +339,9 @@ void *__constant_c_and_count_memset(void *s, unsigned long pattern, #define __HAVE_ARCH_MEMSCAN extern void *memscan(void *addr, int c, size_t size); +#define ARCH_HAS_USER_NOCACHE 1 +asmlinkage void clear_page_nocache(void *page); + #endif /* __KERNEL__ */ #endif /* _ASM_X86_STRING_32_H */ diff --git a/arch/x86/include/asm/string_64.h b/arch/x86/include/asm/string_64.h index 19e2c46..ca23d1d 100644 --- a/arch/x86/include/asm/string_64.h +++ b/arch/x86/include/asm/string_64.h @@ -3,6 +3,8 @@ #ifdef __KERNEL__ +#include + /* Written 2002 by Andi Kleen */ /* Only used for special circumstances. Stolen from i386/string.h */ @@ -63,6 +65,9 @@ char *strcpy(char *dest, const char *src); char *strcat(char *dest, const char *src); int strcmp(const char *cs, const char *ct); +#define ARCH_HAS_USER_NOCACHE 1 +asmlinkage void clear_page_nocache(void *page); + #endif /* __KERNEL__ */ #endif /* _ASM_X86_STRING_64_H */ diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile index b00f678..a8ad6dd 100644 --- a/arch/x86/lib/Makefile +++ b/arch/x86/lib/Makefile @@ -23,6 +23,7 @@ lib-y += memcpy_$(BITS).o lib-$(CONFIG_SMP) += rwlock.o lib-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem.o lib-$(CONFIG_INSTRUCTION_DECODER) += insn.o inat.o +lib-y += clear_page_nocache_$(BITS).o obj-y += msr.o msr-reg.o msr-reg-export.o diff --git a/arch/x86/lib/clear_page_nocache_32.S b/arch/x86/lib/clear_page_nocache_32.S new file mode 100644 index 0000000..2394e0c --- /dev/null +++ b/arch/x86/lib/clear_page_nocache_32.S @@ -0,0 +1,30 @@ +#include +#include + +/* + * Zero a page avoiding the caches + * rdi page + */ +ENTRY(clear_page_nocache) + CFI_STARTPROC + mov %eax,%edi + xorl %eax,%eax + movl $4096/64,%ecx + .p2align 4 +.Lloop: + decl %ecx +#define PUT(x) movnti %eax,x*8(%edi) ; movnti %eax,x*8+4(%edi) + PUT(0) + PUT(1) + PUT(2) + PUT(3) + PUT(4) + PUT(5) + PUT(6) + PUT(7) + lea 64(%edi),%edi + jnz .Lloop + nop + ret + CFI_ENDPROC +ENDPROC(clear_page_nocache) diff --git a/arch/x86/lib/clear_page_nocache_64.S b/arch/x86/lib/clear_page_nocache_64.S new file mode 100644 index 0000000..ee16d15 --- /dev/null +++ b/arch/x86/lib/clear_page_nocache_64.S @@ -0,0 +1,29 @@ +#include +#include + +/* + * Zero a page avoiding the caches + * rdi page + */ +ENTRY(clear_page_nocache) + CFI_STARTPROC + xorl %eax,%eax + movl $4096/64,%ecx + .p2align 4 +.Lloop: + decl %ecx +#define PUT(x) movnti %rax,x*8(%rdi) + movnti %rax,(%rdi) + PUT(1) + PUT(2) + PUT(3) + PUT(4) + PUT(5) + PUT(6) + PUT(7) + leaq 64(%rdi),%rdi + jnz .Lloop + nop + ret + CFI_ENDPROC +ENDPROC(clear_page_nocache) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 76dcd9d..20888b4 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -1209,3 +1209,10 @@ good_area: up_read(&mm->mmap_sem); } + +void clear_user_highpage_nocache(struct page *page, unsigned long vaddr) +{ + void *p = kmap_atomic(page, KM_USER0); + clear_page_nocache(p); + kunmap_atomic(p); +}