Messages in this thread | | | Date | Fri, 20 Aug 2010 08:33:46 -0700 | From | Greg KH <> | Subject | Re: [PATCH] [RFCv2] notify userspace about time changes |
| |
On Fri, Aug 20, 2010 at 11:37:23AM +0300, Kirill A. Shutemov wrote: > On Thu, Aug 19, 2010 at 08:31:27AM -0700, Greg KH wrote: > > On Thu, Aug 19, 2010 at 11:36:12AM +0300, Kirill A. Shutemov wrote: > > > On Wed, Aug 18, 2010 at 09:09:37PM -0700, Greg KH wrote: > > > > On Wed, Aug 18, 2010 at 04:53:03PM -0700, Andrew Morton wrote: > > > > > Is sysfs the right interface for this thing? Bear in mind that > > > > > CONFIG_SYSFS does exist. > > > > > > > > > > > + fd = open("/sys/kernel/time_notify", O_WRONLY); > > > > > > + fdprintf(fd, "%d 1 0 1 1", efd); > > > > > > > > > > why not > > > > > > > > > > sys_time_notify(efd, 1, 0, 1, 1); > > > > > > > > Yeah, that would be much better than a sysfs file, this is abusing the > > > > sysfs interface quite a lot. > > > > > > Do you really think, that increasing number of syscalls is better then > > > fs-based interfaces? > > > > As you are pretty much creating a new syscall here anyway, there is no > > problem with making it a real one, right? > > I think Linux has too many syscalls. Significant part these interfaces > would be better to map to a filesystem[s].
What is the difference between a syscall and a filesystem interface? They are both things that we can not change in the future and need to be preserved and documented.
Don't be afraid of syscall's, they don't bite :)
> > That way you can properly > > handle the user/kernel documentation and persistance over time (i.e. you > > can't change it.) > > On the other, hand properly designed fs-based interface requires less > modification of userspeace to use it. Acctually, you can use most of > fs-based intefaces directly from shell. No need in libc modifications and > utilities to use it from shell or other script language. > See cgroup, for example. > > > So yes, a syscall would be better, especially as this does not exactly > > fit into the model of sysfs, right? > > Yes, sysfs is not the best place for it, but...
You just answered your own question. Please don't make it in sysfs, make it a syscall as it does not fit into sysfs.
thanks,
greg "constantly fighting to keep /sys/ from being like /proc/" k-h
| |