From 7b27509fc62686c53e9301560034e6b0b001174d Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Sat, 29 Oct 2011 12:15:04 -0200 Subject: perf hists browser: Warn about lost events Just like the old perf top --tui and the --stdio version. But because we have the initial menu to choose which event to show in a session with multiple events we can see how many chunks were lost in each of the event types, clarifying which events are being affected the most. 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-47yyqbubmjzch2chezmb21m6@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/ui/browsers/hists.c | 49 ++++++++++++++++++++++++++++++++----- 1 file changed, 43 insertions(+), 6 deletions(-) (limited to 'tools/perf/util/ui/browsers/hists.c') diff --git a/tools/perf/util/ui/browsers/hists.c b/tools/perf/util/ui/browsers/hists.c index b8733c0770cd..d0c94b459685 100644 --- a/tools/perf/util/ui/browsers/hists.c +++ b/tools/perf/util/ui/browsers/hists.c @@ -295,6 +295,15 @@ static void hist_browser__set_folding(struct hist_browser *self, bool unfold) ui_browser__reset_index(&self->b); } +static void ui_browser__warn_lost_events(struct ui_browser *browser) +{ + ui_browser__warning(browser, 4, + "Events are being lost, check IO/CPU overload!\n\n" + "You may want to run 'perf' using a RT scheduler policy:\n\n" + " perf top -r 80\n\n" + "Or reduce the sampling frequency."); +} + static int hist_browser__run(struct hist_browser *self, const char *ev_name, void(*timer)(void *arg), void *arg, int delay_secs) { @@ -318,8 +327,15 @@ static int hist_browser__run(struct hist_browser *self, const char *ev_name, case K_TIMER: timer(arg); ui_browser__update_nr_entries(&self->b, self->hists->nr_entries); - hists__browser_title(self->hists, title, sizeof(title), - ev_name); + + if (self->hists->stats.nr_lost_warned != + self->hists->stats.nr_events[PERF_RECORD_LOST]) { + self->hists->stats.nr_lost_warned = + self->hists->stats.nr_events[PERF_RECORD_LOST]; + ui_browser__warn_lost_events(&self->b); + } + + hists__browser_title(self->hists, title, sizeof(title), ev_name); ui_browser__show_title(&self->b, title); continue; case 'D': { /* Debug */ @@ -883,7 +899,7 @@ static int perf_evsel__hists_browse(struct perf_evsel *evsel, int nr_events, goto out_free_stack; case 'a': if (!browser->has_symbols) { - ui_browser__warning(&browser->b, + ui_browser__warning(&browser->b, delay_secs * 2, "Annotation is only available for symbolic views, " "include \"sym\" in --sort to use it."); continue; @@ -1061,6 +1077,7 @@ out: struct perf_evsel_menu { struct ui_browser b; struct perf_evsel *selection; + bool lost_events, lost_events_warned; }; static void perf_evsel_menu__write(struct ui_browser *browser, @@ -1073,14 +1090,29 @@ static void perf_evsel_menu__write(struct ui_browser *browser, unsigned long nr_events = evsel->hists.stats.nr_events[PERF_RECORD_SAMPLE]; const char *ev_name = event_name(evsel); char bf[256], unit; + const char *warn = " "; + size_t printed; ui_browser__set_color(browser, current_entry ? HE_COLORSET_SELECTED : HE_COLORSET_NORMAL); nr_events = convert_unit(nr_events, &unit); - snprintf(bf, sizeof(bf), "%lu%c%s%s", nr_events, - unit, unit == ' ' ? "" : " ", ev_name); - slsmg_write_nstring(bf, browser->width); + printed = snprintf(bf, sizeof(bf), "%lu%c%s%s", nr_events, + unit, unit == ' ' ? "" : " ", ev_name); + slsmg_printf("%s", bf); + + nr_events = evsel->hists.stats.nr_events[PERF_RECORD_LOST]; + if (nr_events != 0) { + menu->lost_events = true; + if (!current_entry) + ui_browser__set_color(browser, HE_COLORSET_TOP); + nr_events = convert_unit(nr_events, &unit); + snprintf(bf, sizeof(bf), ": %ld%c%schunks LOST!", nr_events, + unit, unit == ' ' ? "" : " "); + warn = bf; + } + + slsmg_write_nstring(warn, browser->width - printed); if (current_entry) menu->selection = evsel; @@ -1105,6 +1137,11 @@ static int perf_evsel_menu__run(struct perf_evsel_menu *menu, switch (key) { case K_TIMER: timer(arg); + + if (!menu->lost_events_warned && menu->lost_events) { + ui_browser__warn_lost_events(&menu->b); + menu->lost_events_warned = true; + } continue; case K_RIGHT: case K_ENTER: -- cgit v1.2.3-59-g8ed1b