Messages in this thread | | | Date | Thu, 1 Jan 1998 15:29:25 +1100 | From | Richard Gooch <> | Subject | Re: PROPOSAL: /proc/dev |
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H. Peter Anvin writes: > > Why not? If you could give us some good reasons why not then we probably > > will drop it. But several times, I have heard this come up, and never a > > good reason why it shouldn't be done. The two reasons that I have heard are: > > 1) Memory usage -- so if you can't spare the memory, don't use it! > > 2) Lack of user configurablity (IE different permissions, different names) > > -- so we have callbacks through a userspace daemon. Or we let people > > write really simple kernelspace modules. (Basicly a big select and a > > function call or three with constant arguments for each case.) > > These are the arguments the proponents shoot down constantly, but they > never address any of the REAL (IMO) problems (although the kernel > space usage is likely to be prohibitive if done anything remotely like > correctly.) YOU REALLY DON'T WANT CALLBACKS -- if you do, then your > device performance and reliability is going straight into the toilet.
We already have callbacks for the f_ops. So this scheme will increase the callback depth by one. Is that really a big deal? We're only talking about a handfull of cycles or so. I'm sure the syscall overhead is much greater.
> At some point I'll probably get my act together and write an FAQ on > this. I'm sick and tired of rehashing the same argument every four > months for about four years now...
Jeez, take it easy. I'm just trying to be constructive.
Regards,
Richard....
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