On Tuesday 04 September 2007 16:25, Davide Libenzi wrote: > On Tue, 4 Sep 2007, Andrew Morton wrote: > > > > On Tue, 04 Sep 2007 10:03:56 +0200 Michael Kerrisk <[EMAIL PROTECTED]> > > > wrote: > > > Davide, > > > > > > >> Davide -- ping! Can you please offer your comments about this change, > > > >> and > > > >> also thoughts on Jon's and my comments about a more radical API change > > > >> later in this thread. > > > > > > > > IMO the complexity of the resulting API (and resulting patch), and the > > > > ABI > > > > change, is not justified by the added value. > > > > > > Neither of the proposed APIs (either my multiplexed version of timerfd() > > > or Jon's/my idea of using three system calls (like POSIX timers), or > > > the notion of timerfd() integrated with POSIX timers) is more > > > complicated than the existing POSIX timers API. > > > > > > The ABI change doesn't really matter, since timerfd() was broken in 2.6.22 > > > anyway. > > > > > > Both previous APIs provided the features I have described provide: > > > > > > * the ability to fetch the old timer value when applying > > > a new setting > > > > > > * the ability to non-destructively fetch the amount of time remaining > > > on a timer. > > > > > > This is clearly useful for timers -- but you have not explained why > > > you think this is not necessary for timerfd timers. > > > > <wakes up> > > > > I'd have thought that the existing stuff would be near-useless without the > > capabilities which you describe? > > Useless like it'd be a motorcycle w/out a cup-holder :) > Seriously, the ability to get the previous values from "something" could > have a meaning if this something is a shared global resource (like signals > for example). In the timerfd case this makes little sense, since you can > create as many timerfd as you like and you do not need to share a single > one by changing/restoring the original context.
I think at least ability to read remaining time from a timerfd is needed. -- vda - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
