Re: [PATCH 6/7] perf hist: Use cached rbtrees

[Davidlohr Bueso <dave@stgolabs.net>]

On Tue, 22 Jan 2019, Arnaldo Carvalho de Melo wrote:

>Em Thu, Dec 06, 2018 at 11:18:18AM -0800, Davidlohr Bueso escreveu:
>> At the cost of an extra pointer, we can avoid the O(logN) cost
>> of finding the first element in the tree (smallest node), which
>> is something heavily required for histograms. Specifically, the
>> following are converted to rb_root_cached, and users accordingly:
>>
>> hist::entries_in_array
>> hist::entries_in
>> hist::entries
>> hist::entries_collapsed
>> hist_entry::hroot_in
>> hist_entry::hroot_out
>
>  CC       /tmp/build/perf/util/hist.o
>ui/browsers/hists.c: In function ???hierarchy_set_folding???:
>ui/browsers/hists.c:511:21: error: passing argument 1 of ???rb_first??? from incompatible pointer type [-Werror=incompatible-pointer-types]
>  for (nd = rb_first(&he->hroot_out); nd; nd = rb_next(nd)) {
>                     ^~~~~~~~~~~~~~
>In file included from ui/browsers/hists.c:8:
>/home/acme/git/perf/tools/include/linux/rbtree.h:83:24: note: expected ???const struct rb_root *??? but argument is of type ???struct rb_root_cached *???
> extern struct rb_node *rb_first(const struct rb_root *);
>                        ^~~~~~~~
>ui/browsers/hists.c: In function ???__hist_browser__set_folding???:
>ui/browsers/hists.c:569:16: error: passing argument 1 of ???rb_first??? from incompatible pointer type [-Werror=incompatible-pointer-types]
>  nd = rb_first(&browser->hists->entries);
>                ^~~~~~~~~~~~~~~~~~~~~~~~
>
>So I added this on top, please check:

Looks good thanks (sorry I thought I had tested all this -- even ran perf
several times :/)

Thanks,
Davidlohr