Hi Andrew, On Wed, 22 May 2019 11:33:15 -0700 Andrew Morton <[email protected]> wrote:
> On Wed, 22 May 2019 13:25:50 +0200 Boris Brezillon > <[email protected]> wrote: > > > Some users might need extra context to compare 2 elements. This patch > > adds the sort_r() which is similar to the qsort_r() variant of qsort(). > > > > Signed-off-by: Boris Brezillon <[email protected]> > > --- > > Hello, > > > > A few more details about this patch. > > > > Even though I post it as a standalone patch, I do intend to use it in > > a real driver (v4l2 driver), just didn't want to have it burried in a > > huge patch series. > > > > Note that sort() and sort_r() are now implemented as wrappers around > > do_sort() so that most of the code can be shared. I initially went for > > a solution that implemented sort() as a wrapper around sort_r() (which > > basically contained the do_sort() logic without the cmp_func arg) > > but realized this was adding one extra indirect call (the compare func > > wrapper), which I know are being chased. > > Please move the above text into the changelog. It's probably useful > and we can afford the disk space ;) Will do. > > > There's another option, but I'm pretty sure other people already > > considered it and thought it was not a good idea as it would make > > the code size grow: move the code to sort.h as inline funcs/macros so > > that the compiler can optimize things out and replace the indirect > > cmp_func() calls by direct ones. I just tried it, and it makes my .o > > file grow by 576 bytes, given that we currently have 122 users of > > this function, that makes the kernel code grow by ~70k (that's kind > > of a max estimate since not all users will be compiled in). > > eep, let's not do that. > > > --- a/include/linux/sort.h > > +++ b/include/linux/sort.h > > Patch otherwise looks OK. Please include it with the patch series > which uses it. Feel free to add > > Acked-by: Andrew Morton <[email protected]> Thanks for your review. Boris
