From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752255Ab1CJIT2 (ORCPT ); Thu, 10 Mar 2011 03:19:28 -0500 Received: from filtteri2.pp.htv.fi ([213.243.153.185]:52358 "EHLO filtteri2.pp.htv.fi" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752120Ab1CJITY (ORCPT ); Thu, 10 Mar 2011 03:19:24 -0500 X-Greylist: delayed 520 seconds by postgrey-1.27 at vger.kernel.org; Thu, 10 Mar 2011 03:19:23 EST Date: Thu, 10 Mar 2011 10:19:21 +0200 From: Alexander Shishkin To: Kay Sievers Cc: Andrew Morton , linux-kernel@vger.kernel.org, Ken MacLeod , Shaun Reich , Thomas Gleixner , Alexander Viro , Greg Kroah-Hartman , Feng Tang , Michael Tokarev , Marcelo Tosatti , John Stultz , Chris Friesen , "Kirill A. Shutemov" , Artem Bityutskiy , Davide Libenzi , linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org, Michael Kerrisk , Alexander Shishkin Subject: Re: [RFCv4] timerfd: add TFD_NOTIFY_CLOCK_SET to watch for clock changes Message-ID: <20110310081921.GC11410@shisha.kicks-ass.net> References: <1299681411-9227-1-git-send-email-virtuoso@slind.org> <20110309162513.5058c824.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=koi8-r Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Mar 10, 2011 at 01:36:18AM +0100, Kay Sievers wrote: > On Thu, Mar 10, 2011 at 01:25, Andrew Morton wrote: > > On Wed, š9 Mar 2011 16:36:51 +0200 > > Alexander Shishkin wrote: > > > >> Changes since v3: > >> š- changed timerfd_settime() semantics (see below) > >> Changes since v2: > >> š- replaced sysfs interface with a syscall > >> š- added sysctl/procfs handle to set a limit to the number of users > >> š- fixed issues pointed out by Greg. > >> Changes since v1: > >> š- updated against 2.6.36-rc1, > >> š- added notification/filtering options, > >> š- added Documentation/ABI/sysfs-kernel-time-notify interface description. > > > It would be helpful to know if the identified users of this feature > > actually find it useful and adequate. šI guess the most common > > application is the 1,001 desktop clock widgets. šDo you have any > > feedback from any of the owners of those? > > We want it for systemd, to provide cron-like functionality but without > the need to stupidly wake up every minute and check the system time > for possible jumps. > > It also sounds useful for a generic resume (after system suspend) > notification for applications, which isn't really possible today. Yes, but with John's CLOCK_BOOTTIME patches (which are in the tip tree currently) it will be. Regards, -- Alex From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexander Shishkin Subject: Re: [RFCv4] timerfd: add TFD_NOTIFY_CLOCK_SET to watch for clock changes Date: Thu, 10 Mar 2011 10:19:21 +0200 Message-ID: <20110310081921.GC11410@shisha.kicks-ass.net> References: <1299681411-9227-1-git-send-email-virtuoso@slind.org> <20110309162513.5058c824.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=koi8-r Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Andrew Morton , linux-kernel@vger.kernel.org, Ken MacLeod , Shaun Reich , Thomas Gleixner , Alexander Viro , Greg Kroah-Hartman , Feng Tang , Michael Tokarev , Marcelo Tosatti , John Stultz , Chris Friesen , "Kirill A. Shutemov" , Artem Bityutskiy , Davide Libenzi , linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org, Michael Kerrisk , Alexander Shishkin To: Kay Sievers Return-path: Received: from filtteri2.pp.htv.fi ([213.243.153.185]:52358 "EHLO filtteri2.pp.htv.fi" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752120Ab1CJITY (ORCPT ); Thu, 10 Mar 2011 03:19:24 -0500 Content-Disposition: inline In-Reply-To: Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Thu, Mar 10, 2011 at 01:36:18AM +0100, Kay Sievers wrote: > On Thu, Mar 10, 2011 at 01:25, Andrew Morton wrote: > > On Wed, =9A9 Mar 2011 16:36:51 +0200 > > Alexander Shishkin wrote: > > > >> Changes since v3: > >> =9A- changed timerfd_settime() semantics (see below) > >> Changes since v2: > >> =9A- replaced sysfs interface with a syscall > >> =9A- added sysctl/procfs handle to set a limit to the number of us= ers > >> =9A- fixed issues pointed out by Greg. > >> Changes since v1: > >> =9A- updated against 2.6.36-rc1, > >> =9A- added notification/filtering options, > >> =9A- added Documentation/ABI/sysfs-kernel-time-notify interface de= scription. >=20 > > It would be helpful to know if the identified users of this feature > > actually find it useful and adequate. =9AI guess the most common > > application is the 1,001 desktop clock widgets. =9ADo you have any > > feedback from any of the owners of those? >=20 > We want it for systemd, to provide cron-like functionality but withou= t > the need to stupidly wake up every minute and check the system time > for possible jumps. >=20 > It also sounds useful for a generic resume (after system suspend) > notification for applications, which isn't really possible today. Yes, but with John's CLOCK_BOOTTIME patches (which are in the tip tree currently) it will be. Regards, -- Alex -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel= " in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html