From 900e14a8f5a49e987790b93c7906989b22075f1b Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Tue, 11 Oct 2011 16:15:39 -0300 Subject: [PATCH] perf hists browser: Recalculate browser pointers after resort/decay In browsers that access dynamic underlying data structures, like in the hists browser and its hist_entry rb_tree, we need to revalidate any reference to the underlying data structure, because they can have gone away, decayed. This fixes a problem where after a while the top entries get behind the top of the screen, i.e. the top_idx stays at 0, which means it is at the first entry in the rb_tree when in fact it wasn't because the browser->top didn't got revalidated after the timer ran and the underlying data structure got updated. Cc: David Ahern Cc: Frederic Weisbecker Cc: Mike Galbraith Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-mhje66qssdko24q67a2lhlho@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/ui/browser.c | 23 +++++++++++++++++++++++ tools/perf/util/ui/browser.h | 1 + tools/perf/util/ui/browsers/hists.c | 9 ++------- 3 files changed, 26 insertions(+), 7 deletions(-) diff --git a/tools/perf/util/ui/browser.c b/tools/perf/util/ui/browser.c index 611219f8068..5911bba6385 100644 --- a/tools/perf/util/ui/browser.c +++ b/tools/perf/util/ui/browser.c @@ -230,6 +230,29 @@ int ui_browser__refresh(struct ui_browser *self) return 0; } +/* + * Here we're updating nr_entries _after_ we started browsing, i.e. we have to + * forget about any reference to any entry in the underlying data structure, + * that is why we do a SEEK_SET. Think about 'perf top' in the hists browser + * after an output_resort and hist decay. + */ +void ui_browser__update_nr_entries(struct ui_browser *browser, u32 nr_entries) +{ + off_t offset = nr_entries - browser->nr_entries; + + browser->nr_entries = nr_entries; + + if (offset < 0) { + if (browser->top_idx < (u64)-offset) + offset = -browser->top_idx; + + browser->index += offset; + browser->top_idx += offset; + } + + browser->seek(browser, browser->top_idx, SEEK_SET); +} + int ui_browser__run(struct ui_browser *self) { struct newtExitStruct es; diff --git a/tools/perf/util/ui/browser.h b/tools/perf/util/ui/browser.h index fc63dda1091..d42be43ac0e 100644 --- a/tools/perf/util/ui/browser.h +++ b/tools/perf/util/ui/browser.h @@ -41,6 +41,7 @@ int ui_browser__show(struct ui_browser *self, const char *title, void ui_browser__hide(struct ui_browser *self); int ui_browser__refresh(struct ui_browser *self); int ui_browser__run(struct ui_browser *self); +void ui_browser__update_nr_entries(struct ui_browser *browser, u32 nr_entries); void ui_browser__rb_tree_seek(struct ui_browser *self, off_t offset, int whence); unsigned int ui_browser__rb_tree_refresh(struct ui_browser *self); diff --git a/tools/perf/util/ui/browsers/hists.c b/tools/perf/util/ui/browsers/hists.c index e64d9527f14..9ece8435353 100644 --- a/tools/perf/util/ui/browsers/hists.c +++ b/tools/perf/util/ui/browsers/hists.c @@ -332,13 +332,7 @@ static int hist_browser__run(struct hist_browser *self, const char *ev_name, case -1: /* FIXME we need to check if it was es.reason == NEWT_EXIT_TIMER */ timer(arg); - /* - * The timer may have changed the number of entries. - * XXX: Find better way to keep this in synch, probably - * removing this timer function altogether and just sync - * using the hists->lock... - */ - self->b.nr_entries = self->hists->nr_entries; + ui_browser__update_nr_entries(&self->b, self->hists->nr_entries); hists__browser_title(self->hists, title, sizeof(title), ev_name, self->dso_filter, self->thread_filter); @@ -985,6 +979,7 @@ do_annotate: hist_entry__tui_annotate(he, evsel->idx, nr_events, timer, arg, delay_secs); + ui_browser__update_nr_entries(&browser->b, browser->hists->nr_entries); } else if (choice == browse_map) map__browse(browser->selection->map); else if (choice == zoom_dso) { -- 2.20.1