From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qa0-f43.google.com (mail-qa0-f43.google.com [209.85.216.43]) by kanga.kvack.org (Postfix) with ESMTP id 1CA196B0039 for ; Thu, 30 Jan 2014 19:01:48 -0500 (EST) Received: by mail-qa0-f43.google.com with SMTP id o15so5377500qap.2 for ; Thu, 30 Jan 2014 16:01:47 -0800 (PST) Received: from mail-qc0-x22e.google.com (mail-qc0-x22e.google.com [2607:f8b0:400d:c01::22e]) by mx.google.com with ESMTPS id s22si5934225qge.116.2014.01.30.16.01.47 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 30 Jan 2014 16:01:47 -0800 (PST) Received: by mail-qc0-f174.google.com with SMTP id x13so5987636qcv.19 for ; Thu, 30 Jan 2014 16:01:47 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <52EAC755.5080408@linaro.org> References: <52E709C0.1050006@linaro.org> <20140130084657.GA31508@infradead.org> <52EAC755.5080408@linaro.org> From: Kay Sievers Date: Fri, 31 Jan 2014 01:01:27 +0100 Message-ID: Subject: Re: [RFC] shmgetfd idea Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: John Stultz Cc: Christoph Hellwig , "linux-mm@kvack.org" , Greg KH , Android Kernel Team , Andrew Morton , Mel Gorman , Hugh Dickins , Dave Hansen , Rik van Riel , Michel Lespinasse , Johannes Weiner , "H. Peter Anvin" , Neil Brown , Andrea Arcangeli , Takahiro Akashi , Minchan Kim , Lennart Poettering On Thu, Jan 30, 2014 at 10:42 PM, John Stultz wrote: > On 01/30/2014 08:02 AM, Kay Sievers wrote: >> On Thu, Jan 30, 2014 at 9:46 AM, Christoph Hellwig wrote: >>> On Mon, Jan 27, 2014 at 05:37:04PM -0800, John Stultz wrote: >>>> In working with ashmem and looking briefly at kdbus' memfd ideas, >>>> there's a commonality that both basically act as a method to provide >>>> applications with unlinked tmpfs/shmem fds. >>> Just use O_TMPFILE on a tmpfs file and you're done. >> Ashmem and kdbus can name the deleted files, which is useful for >> debugging and tools to show the associated name for the file >> descriptor. They also show up in /proc/$PID/maps/ and possibly in >> /proc/$PID/fd/. >> >> O_TMPFILE always creates files with just the name "/". Unless that is >> changed we wouldn't want switch over to O_TMPFILE, because we would >> lose that nice feature. > > Not sure, but would Colin's vma-naming patch (or something like it) help > address this? > https://lkml.org/lkml/2013/10/30/518 Hmm, I don't think so, this seems to be about anonymous memory only, but shmem files are not anonymous. We actually just really want the actual file names, ashmem too, like shmem_file_setup() accepts the name for the unlinked file to create. Kay -- 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: email@kvack.org