From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.91] helo=mail.sourceforge.net) by sc8-sf-list1-new.sourceforge.net with esmtp (Exim 4.43) id 1Hc2EY-0002AZ-Ez for user-mode-linux-devel@lists.sourceforge.net; Thu, 12 Apr 2007 09:33:18 -0700 Received: from [198.99.130.12] (helo=saraswathi.solana.com) by mail.sourceforge.net with esmtp (Exim 4.44) id 1Hc2EX-0000fj-Ol for user-mode-linux-devel@lists.sourceforge.net; Thu, 12 Apr 2007 09:33:18 -0700 Date: Thu, 12 Apr 2007 12:28:05 -0400 From: Jeff Dike Message-ID: <20070412162805.GA7255@c2.user-mode-linux.org> Mime-Version: 1.0 Content-Disposition: inline Subject: [uml-devel] [ PATCH 6/6 ] UML - Speed page fault path List-Id: The user-mode Linux development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: user-mode-linux-devel-bounces@lists.sourceforge.net Errors-To: user-mode-linux-devel-bounces@lists.sourceforge.net To: Andrew Morton Cc: LKML , uml-devel Give the page fault code a specialized path. There is only one page to look at, so there's no point in going into the general page table walking code. There's only going to be one host operation, so there are no opportunities for merging. So, we go straight to the pte we want, figure out what needs doing, and do it. While I was in here, I fixed the wart where the address passed to unmap was a void *, but an unsigned long to map and protect. This gives me just under 10% on a kernel build. Signed-off-by: Jeff Dike -- arch/um/include/os.h | 2 - arch/um/include/skas/mode_kern_skas.h | 2 + arch/um/kernel/skas/tlb.c | 66 ++++++++++++++++++++++++++++++++-- arch/um/kernel/tlb.c | 4 +- arch/um/os-Linux/skas/mem.c | 4 +- 5 files changed, 72 insertions(+), 6 deletions(-) Index: linux-2.6.21-mm/arch/um/include/skas/mode_kern_skas.h =================================================================== --- linux-2.6.21-mm.orig/arch/um/include/skas/mode_kern_skas.h 2007-04-12 11:34:40.000000000 -0400 +++ linux-2.6.21-mm/arch/um/include/skas/mode_kern_skas.h 2007-04-12 11:48:33.000000000 -0400 @@ -33,6 +33,8 @@ extern unsigned long set_task_sizes_skas extern int start_uml_skas(void); extern int external_pid_skas(struct task_struct *task); extern int thread_pid_skas(struct task_struct *task); +extern void flush_tlb_page_skas(struct vm_area_struct *vma, + unsigned long address); #define kmem_end_skas (host_task_size - 1024 * 1024) Index: linux-2.6.21-mm/arch/um/kernel/skas/tlb.c =================================================================== --- linux-2.6.21-mm.orig/arch/um/kernel/skas/tlb.c 2007-04-12 11:34:40.000000000 -0400 +++ linux-2.6.21-mm/arch/um/kernel/skas/tlb.c 2007-04-12 11:48:33.000000000 -0400 @@ -32,8 +32,7 @@ static int do_ops(union mm_context *mmu, op->u.mmap.offset, finished, flush); break; case MUNMAP: - ret = unmap(&mmu->skas.id, - (void *) op->u.munmap.addr, + ret = unmap(&mmu->skas.id, op->u.munmap.addr, op->u.munmap.len, finished, flush); break; case MPROTECT: @@ -94,3 +93,66 @@ void force_flush_all_skas(void) unsigned long end = proc_mm ? task_size : CONFIG_STUB_START; fix_range(current->mm, 0, end, 1); } + +void flush_tlb_page_skas(struct vm_area_struct *vma, unsigned long address) +{ + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + pte_t *pte; + struct mm_struct *mm = vma->vm_mm; + void *flush = NULL; + int r, w, x, err = 0; + struct mm_id *mm_id; + + pgd = pgd_offset(vma->vm_mm, address); + if(!pgd_present(*pgd)) + goto kill; + + pud = pud_offset(pgd, address); + if(!pud_present(*pud)) + goto kill; + + pmd = pmd_offset(pud, address); + if(!pmd_present(*pmd)) + goto kill; + + pte = pte_offset_kernel(pmd, address); + + r = pte_read(*pte); + w = pte_write(*pte); + x = pte_exec(*pte); + if (!pte_young(*pte)) { + r = 0; + w = 0; + } else if (!pte_dirty(*pte)) { + w = 0; + } + + mm_id = &mm->context.skas.id; + if(pte_newpage(*pte)){ + if(pte_present(*pte)){ + unsigned long long offset; + int fd; + + fd = phys_mapping(pte_val(*pte) & PAGE_MASK, &offset); + err = map(mm_id, address, PAGE_SIZE, r, w, x, fd, + offset, 1, &flush); + } + else err = unmap(mm_id, address, PAGE_SIZE, 1, &flush); + } + else if(pte_newprot(*pte)) + err = protect(mm_id, address, PAGE_SIZE, r, w, x, 1, &flush); + + if(err) + goto kill; + + *pte = pte_mkuptodate(*pte); + + return; + +kill: + printk("Failed to flush page for address 0x%lx\n", address); + force_sig(SIGKILL, current); +} + Index: linux-2.6.21-mm/arch/um/kernel/tlb.c =================================================================== --- linux-2.6.21-mm.orig/arch/um/kernel/tlb.c 2007-04-12 11:46:27.000000000 -0400 +++ linux-2.6.21-mm/arch/um/kernel/tlb.c 2007-04-12 11:48:33.000000000 -0400 @@ -380,7 +380,9 @@ pte_t *addr_pte(struct task_struct *task void flush_tlb_page(struct vm_area_struct *vma, unsigned long address) { address &= PAGE_MASK; - flush_tlb_range(vma, address, address + PAGE_SIZE); + + CHOOSE_MODE(flush_tlb_range(vma, address, address + PAGE_SIZE), + flush_tlb_page_skas(vma, address)); } void flush_tlb_all(void) Index: linux-2.6.21-mm/arch/um/include/os.h =================================================================== --- linux-2.6.21-mm.orig/arch/um/include/os.h 2007-04-12 11:38:51.000000000 -0400 +++ linux-2.6.21-mm/arch/um/include/os.h 2007-04-12 11:48:33.000000000 -0400 @@ -302,7 +302,7 @@ extern long syscall_stub_data(struct mm_ extern int map(struct mm_id * mm_idp, unsigned long virt, unsigned long len, int r, int w, int x, int phys_fd, unsigned long long offset, int done, void **data); -extern int unmap(struct mm_id * mm_idp, void *addr, unsigned long len, +extern int unmap(struct mm_id * mm_idp, unsigned long addr, unsigned long len, int done, void **data); extern int protect(struct mm_id * mm_idp, unsigned long addr, unsigned long len, int r, int w, int x, int done, Index: linux-2.6.21-mm/arch/um/os-Linux/skas/mem.c =================================================================== --- linux-2.6.21-mm.orig/arch/um/os-Linux/skas/mem.c 2007-04-12 11:34:40.000000000 -0400 +++ linux-2.6.21-mm/arch/um/os-Linux/skas/mem.c 2007-04-12 11:48:33.000000000 -0400 @@ -219,8 +219,8 @@ int map(struct mm_id * mm_idp, unsigned return ret; } -int unmap(struct mm_id * mm_idp, void *addr, unsigned long len, int done, - void **data) +int unmap(struct mm_id * mm_idp, unsigned long addr, unsigned long len, + int done, void **data) { int ret; ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751122AbXDLQeF (ORCPT ); Thu, 12 Apr 2007 12:34:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751059AbXDLQd2 (ORCPT ); Thu, 12 Apr 2007 12:33:28 -0400 Received: from saraswathi.solana.com ([198.99.130.12]:50719 "EHLO saraswathi.solana.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751110AbXDLQdY (ORCPT ); Thu, 12 Apr 2007 12:33:24 -0400 Date: Thu, 12 Apr 2007 12:28:05 -0400 From: Jeff Dike To: Andrew Morton Cc: LKML , uml-devel Subject: [ PATCH 6/6 ] UML - Speed page fault path Message-ID: <20070412162805.GA7255@c2.user-mode-linux.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.4.2.2i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Give the page fault code a specialized path. There is only one page to look at, so there's no point in going into the general page table walking code. There's only going to be one host operation, so there are no opportunities for merging. So, we go straight to the pte we want, figure out what needs doing, and do it. While I was in here, I fixed the wart where the address passed to unmap was a void *, but an unsigned long to map and protect. This gives me just under 10% on a kernel build. Signed-off-by: Jeff Dike -- arch/um/include/os.h | 2 - arch/um/include/skas/mode_kern_skas.h | 2 + arch/um/kernel/skas/tlb.c | 66 ++++++++++++++++++++++++++++++++-- arch/um/kernel/tlb.c | 4 +- arch/um/os-Linux/skas/mem.c | 4 +- 5 files changed, 72 insertions(+), 6 deletions(-) Index: linux-2.6.21-mm/arch/um/include/skas/mode_kern_skas.h =================================================================== --- linux-2.6.21-mm.orig/arch/um/include/skas/mode_kern_skas.h 2007-04-12 11:34:40.000000000 -0400 +++ linux-2.6.21-mm/arch/um/include/skas/mode_kern_skas.h 2007-04-12 11:48:33.000000000 -0400 @@ -33,6 +33,8 @@ extern unsigned long set_task_sizes_skas extern int start_uml_skas(void); extern int external_pid_skas(struct task_struct *task); extern int thread_pid_skas(struct task_struct *task); +extern void flush_tlb_page_skas(struct vm_area_struct *vma, + unsigned long address); #define kmem_end_skas (host_task_size - 1024 * 1024) Index: linux-2.6.21-mm/arch/um/kernel/skas/tlb.c =================================================================== --- linux-2.6.21-mm.orig/arch/um/kernel/skas/tlb.c 2007-04-12 11:34:40.000000000 -0400 +++ linux-2.6.21-mm/arch/um/kernel/skas/tlb.c 2007-04-12 11:48:33.000000000 -0400 @@ -32,8 +32,7 @@ static int do_ops(union mm_context *mmu, op->u.mmap.offset, finished, flush); break; case MUNMAP: - ret = unmap(&mmu->skas.id, - (void *) op->u.munmap.addr, + ret = unmap(&mmu->skas.id, op->u.munmap.addr, op->u.munmap.len, finished, flush); break; case MPROTECT: @@ -94,3 +93,66 @@ void force_flush_all_skas(void) unsigned long end = proc_mm ? task_size : CONFIG_STUB_START; fix_range(current->mm, 0, end, 1); } + +void flush_tlb_page_skas(struct vm_area_struct *vma, unsigned long address) +{ + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + pte_t *pte; + struct mm_struct *mm = vma->vm_mm; + void *flush = NULL; + int r, w, x, err = 0; + struct mm_id *mm_id; + + pgd = pgd_offset(vma->vm_mm, address); + if(!pgd_present(*pgd)) + goto kill; + + pud = pud_offset(pgd, address); + if(!pud_present(*pud)) + goto kill; + + pmd = pmd_offset(pud, address); + if(!pmd_present(*pmd)) + goto kill; + + pte = pte_offset_kernel(pmd, address); + + r = pte_read(*pte); + w = pte_write(*pte); + x = pte_exec(*pte); + if (!pte_young(*pte)) { + r = 0; + w = 0; + } else if (!pte_dirty(*pte)) { + w = 0; + } + + mm_id = &mm->context.skas.id; + if(pte_newpage(*pte)){ + if(pte_present(*pte)){ + unsigned long long offset; + int fd; + + fd = phys_mapping(pte_val(*pte) & PAGE_MASK, &offset); + err = map(mm_id, address, PAGE_SIZE, r, w, x, fd, + offset, 1, &flush); + } + else err = unmap(mm_id, address, PAGE_SIZE, 1, &flush); + } + else if(pte_newprot(*pte)) + err = protect(mm_id, address, PAGE_SIZE, r, w, x, 1, &flush); + + if(err) + goto kill; + + *pte = pte_mkuptodate(*pte); + + return; + +kill: + printk("Failed to flush page for address 0x%lx\n", address); + force_sig(SIGKILL, current); +} + Index: linux-2.6.21-mm/arch/um/kernel/tlb.c =================================================================== --- linux-2.6.21-mm.orig/arch/um/kernel/tlb.c 2007-04-12 11:46:27.000000000 -0400 +++ linux-2.6.21-mm/arch/um/kernel/tlb.c 2007-04-12 11:48:33.000000000 -0400 @@ -380,7 +380,9 @@ pte_t *addr_pte(struct task_struct *task void flush_tlb_page(struct vm_area_struct *vma, unsigned long address) { address &= PAGE_MASK; - flush_tlb_range(vma, address, address + PAGE_SIZE); + + CHOOSE_MODE(flush_tlb_range(vma, address, address + PAGE_SIZE), + flush_tlb_page_skas(vma, address)); } void flush_tlb_all(void) Index: linux-2.6.21-mm/arch/um/include/os.h =================================================================== --- linux-2.6.21-mm.orig/arch/um/include/os.h 2007-04-12 11:38:51.000000000 -0400 +++ linux-2.6.21-mm/arch/um/include/os.h 2007-04-12 11:48:33.000000000 -0400 @@ -302,7 +302,7 @@ extern long syscall_stub_data(struct mm_ extern int map(struct mm_id * mm_idp, unsigned long virt, unsigned long len, int r, int w, int x, int phys_fd, unsigned long long offset, int done, void **data); -extern int unmap(struct mm_id * mm_idp, void *addr, unsigned long len, +extern int unmap(struct mm_id * mm_idp, unsigned long addr, unsigned long len, int done, void **data); extern int protect(struct mm_id * mm_idp, unsigned long addr, unsigned long len, int r, int w, int x, int done, Index: linux-2.6.21-mm/arch/um/os-Linux/skas/mem.c =================================================================== --- linux-2.6.21-mm.orig/arch/um/os-Linux/skas/mem.c 2007-04-12 11:34:40.000000000 -0400 +++ linux-2.6.21-mm/arch/um/os-Linux/skas/mem.c 2007-04-12 11:48:33.000000000 -0400 @@ -219,8 +219,8 @@ int map(struct mm_id * mm_idp, unsigned return ret; } -int unmap(struct mm_id * mm_idp, void *addr, unsigned long len, int done, - void **data) +int unmap(struct mm_id * mm_idp, unsigned long addr, unsigned long len, + int done, void **data) { int ret;