subr_rangeset: use pctrie_reclaim_callback in remove_all

[dougm]

Summary

Replace the lookup-and-remove loop in rangeset_remove_all with a call to RANGESET_PCTRIE_RECLAIM_CALLBACK, to avoid the repeated lookups.

[rlibby]

Logic looks good.

This does make me think, should we arrange to have name##_PCTRIE_RECLAIM_CALLBACK take a function pointer that is typed for the first argument? We would then need a cast to pctrie_cb_t for the calls to begin_cb/resume_cb, which I think both gcc and clang are okay with, but I am not actually sure what the standard says. That would help avoid mixing up the two void *s in the callback type and avoid the need for one of the casts in the callback.

[dougm]

In D45584#1039980, @rlibby wrote:

This does make me think, should we arrange to have name##_PCTRIE_RECLAIM_CALLBACK take a function pointer that is typed for the first argument? We would then need a cast to pctrie_cb_t for the calls to begin_cb/resume_cb, which I think both gcc and clang are okay with, but I am not actually sure what the standard says. That would help avoid mixing up the two void *s in the callback type and avoid the need for one of the casts in the callback.

I'm not opposed, though I'm also not sure about the standard. But I think I'll commit these bits first, and consider that next.