From 2eb3d6894ae3b9cc8a94c91458a041c45773f23d Mon Sep 17 00:00:00 2001 From: Davidlohr Bueso Date: Thu, 6 Dec 2018 11:18:18 -0800 Subject: perf hist: Use cached rbtrees 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 Signed-off-by: Davidlohr Bueso Tested-by: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lkml.kernel.org/r/20181206191819.30182-7-dave@stgolabs.net [ Added some missing conversions to rb_first_cached() ] Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/ui/stdio/hist.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'tools/perf/ui/stdio/hist.c') diff --git a/tools/perf/ui/stdio/hist.c b/tools/perf/ui/stdio/hist.c index 74c4ae1f0a05..2a9fa4dcbc2a 100644 --- a/tools/perf/ui/stdio/hist.c +++ b/tools/perf/ui/stdio/hist.c @@ -788,7 +788,8 @@ size_t hists__fprintf(struct hists *hists, bool show_header, int max_rows, indent = hists__overhead_width(hists) + 4; - for (nd = rb_first(&hists->entries); nd; nd = __rb_hierarchy_next(nd, HMD_FORCE_CHILD)) { + for (nd = rb_first_cached(&hists->entries); nd; + nd = __rb_hierarchy_next(nd, HMD_FORCE_CHILD)) { struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node); float percent; -- cgit v1.2.3