From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Sat, 31 May 2003 10:46:18 +0200 From: Ingo Oeser Subject: Always passing mm and vma down (was: [RFC][PATCH] Convert do_no_page() to a hook to avoid DFS race) Message-ID: <20030531104617.J672@nightmaster.csn.tu-chemnitz.de> References: <20030530164150.A26766@us.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20030530164150.A26766@us.ibm.com>; from paulmck@us.ibm.com on Fri, May 30, 2003 at 04:41:50PM -0700 Sender: owner-linux-mm@kvack.org Return-Path: To: "Paul E. McKenney" Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, akpm@digeo.com, hch@infradead.org List-ID: Hi there, On Fri, May 30, 2003 at 04:41:50PM -0700, Paul E. McKenney wrote: > -struct page * > -ia32_install_shared_page (struct vm_area_struct *vma, unsigned long address, int no_share) > +int > +ia32_install_shared_page (struct mm_struct *mm, struct vm_area_struct *vma, unsigned long address, int write_access, pmd_t *pmd) > { > struct page *pg = ia32_shared_page[(address - vma->vm_start)/PAGE_SIZE]; > > get_page(pg); > - return pg; > + return install_new_page(mm, vma, address, write_access, pmd, pg); > } Why do we always pass mm and vma down, even if vma->vm_mm contains the mm, where the vma belongs to? Is the connection between a vma and its mm also protected by the mmap_sem? Is this really necessary or an oversight and we waste a lot of stack in a lot of places? If we just need it for accounting: We need current->mm, if we need it to locate the next vma relatively to this vma, vma->vm_mm is the one. Puzzled Ingo Oeser -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: aart@kvack.org