On Wed, Aug 19, 2020 at 07:00:53AM -0600, Jens Axboe wrote: > On 8/18/20 1:00 PM, James Bottomley wrote: > > On Mon, 2020-08-17 at 13:02 -0700, Jens Axboe wrote: > >> On 8/17/20 12:48 PM, Kees Cook wrote: > >>> On Mon, Aug 17, 2020 at 12:44:34PM -0700, Jens Axboe wrote: > >>>> On 8/17/20 12:29 PM, Kees Cook wrote: > >>>>> On Mon, Aug 17, 2020 at 06:56:47AM -0700, Jens Axboe wrote: > >>>>>> On 8/17/20 2:15 AM, Allen Pais wrote: > >>>>>>> From: Allen Pais <allen.lkml@xxxxxxxxx> > >>>>>>> > >>>>>>> In preparation for unconditionally passing the > >>>>>>> struct tasklet_struct pointer to all tasklet > >>>>>>> callbacks, switch to using the new tasklet_setup() > >>>>>>> and from_tasklet() to pass the tasklet pointer explicitly. > >>>>>> > >>>>>> Who came up with the idea to add a macro 'from_tasklet' that > >>>>>> is just container_of? container_of in the code would be > >>>>>> _much_ more readable, and not leave anyone guessing wtf > >>>>>> from_tasklet is doing. > >>>>>> > >>>>>> I'd fix that up now before everything else goes in... > >>>>> > >>>>> As I mentioned in the other thread, I think this makes things > >>>>> much more readable. It's the same thing that the timer_struct > >>>>> conversion did (added a container_of wrapper) to avoid the > >>>>> ever-repeating use of typeof(), long lines, etc. > >>>> > >>>> But then it should use a generic name, instead of each sub-system > >>>> using some random name that makes people look up exactly what it > >>>> does. I'm not huge fan of the container_of() redundancy, but > >>>> adding private variants of this doesn't seem like the best way > >>>> forward. Let's have a generic helper that does this, and use it > >>>> everywhere. > >>> > >>> I'm open to suggestions, but as things stand, these kinds of > >>> treewide > >> > >> On naming? Implementation is just as it stands, from_tasklet() is > >> totally generic which is why I objected to it. from_member()? Not > >> great with naming... But I can see this going further and then we'll > >> suddenly have tons of these. It's not good for readability. > > > > Since both threads seem to have petered out, let me suggest in > > kernel.h: > > > > #define cast_out(ptr, container, member) \ > > container_of(ptr, typeof(*container), member) > > > > It does what you want, the argument order is the same as container_of > > with the only difference being you name the containing structure > > instead of having to specify its type. > > Not to incessantly bike shed on the naming, but I don't like cast_out, > it's not very descriptive. And it has connotations of getting rid of > something, which isn't really true. I agree, if we want to bike shed, I don't like this color either. > FWIW, I like the from_ part of the original naming, as it has some clues > as to what is being done here. Why not just from_container()? That > should immediately tell people what it does without having to look up > the implementation, even before this becomes a part of the accepted > coding norm. Why are people hating on the well-known and used container_of()? If you really hate to type the type and want a new macro, what about 'container_from()'? (noun/verb is nicer to sort symbols by...) But really, why is this even needed? thanks, greg k-h _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
