Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757204AbZC0PTu (ORCPT ); Fri, 27 Mar 2009 11:19:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752281AbZC0PTl (ORCPT ); Fri, 27 Mar 2009 11:19:41 -0400 Received: from mga09.intel.com ([134.134.136.24]:14298 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751837AbZC0PTl convert rfc822-to-8bit (ORCPT ); Fri, 27 Mar 2009 11:19:41 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.38,432,1233561600"; d="scan'208";a="398084662" From: "Metzger, Markus T" To: Oleg Nesterov CC: "linux-kernel@vger.kernel.org" , "mingo@elte.hu" , "tglx@linutronix.de" , "hpa@zytor.com" , "markus.t.metzger@gmail.com" , "roland@redhat.com" , "eranian@googlemail.com" , "Villacis, Juan" , "ak@linux.jf.intel.com" Date: Fri, 27 Mar 2009 15:18:40 +0000 Subject: RE: [patch 2/14] x86, mm: add release_locked_buffer_on_behalf Thread-Topic: [patch 2/14] x86, mm: add release_locked_buffer_on_behalf Thread-Index: Acmu5+hbF7dUBF/2SIWKmi0/i4wOZQABrVYQ Message-ID: <928CFBE8E7CB0040959E56B4EA41A77E9266B6C0@irsmsx504.ger.corp.intel.com> References: <20090327094836.A11033@sedona.ch.intel.com> <20090327142215.GC14504@redhat.com> In-Reply-To: <20090327142215.GC14504@redhat.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2262 Lines: 63 >-----Original Message----- >From: Oleg Nesterov [mailto:oleg@redhat.com] >Sent: Friday, March 27, 2009 3:22 PM >To: Metzger, Markus T >Cc: linux-kernel@vger.kernel.org; mingo@elte.hu; tglx@linutronix.de; hpa@zytor.com; >markus.t.metzger@gmail.com; roland@redhat.com; eranian@googlemail.com; Villacis, Juan; >ak@linux.jf.intel.com >Subject: Re: [patch 2/14] x86, mm: add release_locked_buffer_on_behalf > >On 03/27, Markus Metzger wrote: >> >> -void release_locked_buffer(void *buffer, size_t size) >> +void release_locked_buffer_on_behalf(struct mm_struct *mm, >> + void *buffer, size_t size) >> { >> unsigned long pgsz = PAGE_ALIGN(size) >> PAGE_SHIFT; >> >> - down_write(¤t->mm->mmap_sem); >> + down_write(&mm->mmap_sem); >> >> - current->mm->total_vm -= pgsz; >> - current->mm->locked_vm -= pgsz; >> + mm->total_vm -= pgsz; >> + mm->locked_vm -= pgsz; >> >> - up_write(¤t->mm->mmap_sem); >> + up_write(&mm->mmap_sem); >> } > >If you change this helper, perhaps you can remove the "void *buffer" >argument? It is not used. Actually, this helper should be renamed. >It doesn't free the memory, it only updates mm->xxx_vm. OK. There's an alloc/free pair. This one is in between to allow another task to free the buffer and get the memory correctly refunded. How about refund_locked_buffer_memory(struct mm_struct *, size_t)? regards, markus. --------------------------------------------------------------------- Intel GmbH Dornacher Strasse 1 85622 Feldkirchen/Muenchen Germany Sitz der Gesellschaft: Feldkirchen bei Muenchen Geschaeftsfuehrer: Douglas Lusk, Peter Gleissner, Hannes Schwaderer Registergericht: Muenchen HRB 47456 Ust.-IdNr. VAT Registration No.: DE129385895 Citibank Frankfurt (BLZ 502 109 00) 600119052 This e-mail and any attachments may contain confidential material for the sole use of the intended recipient(s). Any review or distribution by others is strictly prohibited. If you are not the intended recipient, please contact the sender and delete all copies. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/