[PATCH 1/2] perf report: Add --percent-limit option

[PATCH 1/2] perf report: Add --percent-limit option

[Namhyung Kim]

From: Namhyung Kim <namhyung.kim@lge.com>

The --percent-limit option is for not showing small overheaded entries
in the output.  Maybe we want to set a certain default value like 0.1.

Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/Documentation/perf-report.txt |  4 ++
 tools/perf/builtin-diff.c                |  2 +-
 tools/perf/builtin-report.c              | 21 +++++++--
 tools/perf/builtin-top.c                 |  4 +-
 tools/perf/ui/browsers/hists.c           | 79 +++++++++++++++++++++++++++-----
 tools/perf/ui/gtk/hists.c                | 13 ++++--
 tools/perf/ui/stdio/hist.c               |  7 ++-
 tools/perf/util/hist.h                   | 10 ++--
 8 files changed, 115 insertions(+), 25 deletions(-)

diff --git a/tools/perf/Documentation/perf-report.txt b/tools/perf/Documentation/perf-report.txt
index 7d5f4f38aa52..66dab7410c1d 100644
--- a/tools/perf/Documentation/perf-report.txt
+++ b/tools/perf/Documentation/perf-report.txt
@@ -210,6 +210,10 @@ OPTIONS
 	Demangle symbol names to human readable form. It's enabled by default,
 	disable with --no-demangle.
 
+--percent-limit::
+	Do not show entries which have an overhead under that percent.
+	(Default: 0).
+
 SEE ALSO
 --------
 linkperf:perf-stat[1], linkperf:perf-annotate[1]
diff --git a/tools/perf/builtin-diff.c b/tools/perf/builtin-diff.c
index cabbea5f0bc2..a9d63c1c64c5 100644
--- a/tools/perf/builtin-diff.c
+++ b/tools/perf/builtin-diff.c
@@ -457,7 +457,7 @@ static void hists__process(struct hists *old, struct hists *new)
 		hists__output_resort(new);
 	}
 
-	hists__fprintf(new, true, 0, 0, stdout);
+	hists__fprintf(new, true, 0, 0, 0, stdout);
 }
 
 static int __cmd_diff(void)
diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 0f0cf2472d9d..0a4979bdd4c4 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -52,6 +52,7 @@ struct perf_report {
 	symbol_filter_t		annotate_init;
 	const char		*cpu_list;
 	const char		*symbol_filter_str;
+	float			min_percent;
 	DECLARE_BITMAP(cpu_bitmap, MAX_NR_CPUS);
 };
 
@@ -456,7 +457,7 @@ static int perf_evlist__tty_browse_hists(struct perf_evlist *evlist,
 			continue;
 
 		hists__fprintf_nr_sample_events(rep, hists, evname, stdout);
-		hists__fprintf(hists, true, 0, 0, stdout);
+		hists__fprintf(hists, true, 0, 0, rep->min_percent, stdout);
 		fprintf(stdout, "\n\n");
 	}
 
@@ -575,8 +576,8 @@ static int __cmd_report(struct perf_report *rep)
 	if (use_browser > 0) {
 		if (use_browser == 1) {
 			ret = perf_evlist__tui_browse_hists(session->evlist,
-							help,
-							NULL,
+							help, NULL,
+							rep->min_percent,
 							&session->header.env);
 			/*
 			 * Usually "ret" is the last pressed key, and we only
@@ -587,7 +588,7 @@ static int __cmd_report(struct perf_report *rep)
 
 		} else if (use_browser == 2) {
 			perf_evlist__gtk_browse_hists(session->evlist, help,
-						      NULL);
+						      NULL, rep->min_percent);
 		}
 	} else
 		perf_evlist__tty_browse_hists(session->evlist, rep, help);
@@ -698,6 +699,16 @@ parse_branch_mode(const struct option *opt __maybe_unused,
 	return 0;
 }
 
+static int
+parse_percent_limit(const struct option *opt, const char *str,
+		    int unset __maybe_unused)
+{
+	struct perf_report *rep = opt->value;
+
+	rep->min_percent = strtof(str, NULL);
+	return 0;
+}
+
 int cmd_report(int argc, const char **argv, const char *prefix __maybe_unused)
 {
 	struct perf_session *session;
@@ -807,6 +818,8 @@ int cmd_report(int argc, const char **argv, const char *prefix __maybe_unused)
 	OPT_BOOLEAN(0, "demangle", &symbol_conf.demangle,
 		    "Disable symbol demangling"),
 	OPT_BOOLEAN(0, "mem-mode", &report.mem_mode, "mem access profile"),
+	OPT_CALLBACK(0, "percent-limit", &report, "percent",
+		     "Don't show entries under that percent", parse_percent_limit),
 	OPT_END()
 	};
 
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index c2c973476479..19fe25f6e4f0 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -296,7 +296,7 @@ static void perf_top__print_sym_table(struct perf_top *top)
 				     top->print_entries - printed);
 	putchar('\n');
 	hists__fprintf(&top->sym_evsel->hists, false,
-		       top->print_entries - printed, win_width, stdout);
+		       top->print_entries - printed, win_width, 0, stdout);
 }
 
 static void prompt_integer(int *target, const char *msg)
@@ -580,7 +580,7 @@ static void *display_thread_tui(void *arg)
 	list_for_each_entry(pos, &top->evlist->entries, node)
 		pos->hists.uid_filter_str = top->record_opts.target.uid_str;
 
-	perf_evlist__tui_browse_hists(top->evlist, help, &hbt,
+	perf_evlist__tui_browse_hists(top->evlist, help, &hbt, 0,
 				      &top->session->header.env);
 
 	done = 1;
diff --git a/tools/perf/ui/browsers/hists.c b/tools/perf/ui/browsers/hists.c
index a4268cab1921..9dfde61505cc 100644
--- a/tools/perf/ui/browsers/hists.c
+++ b/tools/perf/ui/browsers/hists.c
@@ -25,6 +25,8 @@ struct hist_browser {
 	struct map_symbol   *selection;
 	int		     print_seq;
 	bool		     show_dso;
+	float		     min_pcnt;
+	u64		     nr_pcnt_entries;
 };
 
 extern void hist_browser__init_hpp(void);
@@ -317,6 +319,8 @@ static int hist_browser__run(struct hist_browser *browser, const char *ev_name,
 
 	browser->b.entries = &browser->hists->entries;
 	browser->b.nr_entries = browser->hists->nr_entries;
+	if (browser->min_pcnt)
+		browser->b.nr_entries = browser->nr_pcnt_entries;
 
 	hist_browser__refresh_dimensions(browser);
 	hists__browser_title(browser->hists, title, sizeof(title), ev_name);
@@ -795,10 +799,15 @@ static unsigned int hist_browser__refresh(struct ui_browser *browser)
 
 	for (nd = browser->top; nd; nd = rb_next(nd)) {
 		struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);
+		float percent = h->stat.period * 100.0 /
+					hb->hists->stats.total_period;
 
 		if (h->filtered)
 			continue;
 
+		if (percent < hb->min_pcnt)
+			continue;
+
 		row += hist_browser__show_entry(hb, h, row);
 		if (row == browser->height)
 			break;
@@ -807,10 +816,18 @@ static unsigned int hist_browser__refresh(struct ui_browser *browser)
 	return row;
 }
 
-static struct rb_node *hists__filter_entries(struct rb_node *nd)
+static struct rb_node *hists__filter_entries(struct rb_node *nd,
+					     struct hists *hists,
+					     float min_pcnt)
 {
 	while (nd != NULL) {
 		struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);
+		float percent = h->stat.period * 100.0 /
+					hists->stats.total_period;
+
+		if (percent < min_pcnt)
+			return NULL;
+
 		if (!h->filtered)
 			return nd;
 
@@ -820,11 +837,16 @@ static struct rb_node *hists__filter_entries(struct rb_node *nd)
 	return NULL;
 }
 
-static struct rb_node *hists__filter_prev_entries(struct rb_node *nd)
+static struct rb_node *hists__filter_prev_entries(struct rb_node *nd,
+						  struct hists *hists,
+						  float min_pcnt)
 {
 	while (nd != NULL) {
 		struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);
-		if (!h->filtered)
+		float percent = h->stat.period * 100.0 /
+					hists->stats.total_period;
+
+		if (!h->filtered && percent >= min_pcnt)
 			return nd;
 
 		nd = rb_prev(nd);
@@ -839,6 +861,9 @@ static void ui_browser__hists_seek(struct ui_browser *browser,
 	struct hist_entry *h;
 	struct rb_node *nd;
 	bool first = true;
+	struct hist_browser *hb;
+
+	hb = container_of(browser, struct hist_browser, b);
 
 	if (browser->nr_entries == 0)
 		return;
@@ -847,13 +872,15 @@ static void ui_browser__hists_seek(struct ui_browser *browser,
 
 	switch (whence) {
 	case SEEK_SET:
-		nd = hists__filter_entries(rb_first(browser->entries));
+		nd = hists__filter_entries(rb_first(browser->entries),
+					   hb->hists, hb->min_pcnt);
 		break;
 	case SEEK_CUR:
 		nd = browser->top;
 		goto do_offset;
 	case SEEK_END:
-		nd = hists__filter_prev_entries(rb_last(browser->entries));
+		nd = hists__filter_prev_entries(rb_last(browser->entries),
+						hb->hists, hb->min_pcnt);
 		first = false;
 		break;
 	default:
@@ -896,7 +923,8 @@ do_offset:
 					break;
 				}
 			}
-			nd = hists__filter_entries(rb_next(nd));
+			nd = hists__filter_entries(rb_next(nd), hb->hists,
+						   hb->min_pcnt);
 			if (nd == NULL)
 				break;
 			--offset;
@@ -929,7 +957,8 @@ do_offset:
 				}
 			}
 
-			nd = hists__filter_prev_entries(rb_prev(nd));
+			nd = hists__filter_prev_entries(rb_prev(nd), hb->hists,
+							hb->min_pcnt);
 			if (nd == NULL)
 				break;
 			++offset;
@@ -1098,14 +1127,17 @@ static int hist_browser__fprintf_entry(struct hist_browser *browser,
 
 static int hist_browser__fprintf(struct hist_browser *browser, FILE *fp)
 {
-	struct rb_node *nd = hists__filter_entries(rb_first(browser->b.entries));
+	struct rb_node *nd = hists__filter_entries(rb_first(browser->b.entries),
+						   browser->hists,
+						   browser->min_pcnt);
 	int printed = 0;
 
 	while (nd) {
 		struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);
 
 		printed += hist_browser__fprintf_entry(browser, h, fp);
-		nd = hists__filter_entries(rb_next(nd));
+		nd = hists__filter_entries(rb_next(nd), browser->hists,
+					   browser->min_pcnt);
 	}
 
 	return printed;
@@ -1324,11 +1356,25 @@ close_file_and_continue:
 	return ret;
 }
 
+static void hist_browser__update_pcnt_entries(struct hist_browser *hb)
+{
+	u64 nr_entries = 0;
+	struct rb_node *nd = rb_first(&hb->hists->entries);
+
+	while (nd) {
+		nr_entries++;
+		nd = hists__filter_entries(rb_next(nd), hb->hists,
+					   hb->min_pcnt);
+	}
+
+	hb->nr_pcnt_entries = nr_entries;
+}
 
 static int perf_evsel__hists_browse(struct perf_evsel *evsel, int nr_events,
 				    const char *helpline, const char *ev_name,
 				    bool left_exits,
 				    struct hist_browser_timer *hbt,
+				    float min_pcnt,
 				    struct perf_session_env *env)
 {
 	struct hists *hists = &evsel->hists;
@@ -1345,6 +1391,11 @@ static int perf_evsel__hists_browse(struct perf_evsel *evsel, int nr_events,
 	if (browser == NULL)
 		return -1;
 
+	if (min_pcnt) {
+		browser->min_pcnt = min_pcnt;
+		hist_browser__update_pcnt_entries(browser);
+	}
+
 	fstack = pstack__new(2);
 	if (fstack == NULL)
 		goto out;
@@ -1684,6 +1735,7 @@ struct perf_evsel_menu {
 	struct ui_browser b;
 	struct perf_evsel *selection;
 	bool lost_events, lost_events_warned;
+	float min_pcnt;
 	struct perf_session_env *env;
 };
 
@@ -1777,6 +1829,7 @@ browse_hists:
 			ev_name = perf_evsel__name(pos);
 			key = perf_evsel__hists_browse(pos, nr_events, help,
 						       ev_name, true, hbt,
+						       menu->min_pcnt,
 						       menu->env);
 			ui_browser__show_title(&menu->b, title);
 			switch (key) {
@@ -1838,6 +1891,7 @@ static bool filter_group_entries(struct ui_browser *self __maybe_unused,
 static int __perf_evlist__tui_browse_hists(struct perf_evlist *evlist,
 					   int nr_entries, const char *help,
 					   struct hist_browser_timer *hbt,
+					   float min_pcnt,
 					   struct perf_session_env *env)
 {
 	struct perf_evsel *pos;
@@ -1851,6 +1905,7 @@ static int __perf_evlist__tui_browse_hists(struct perf_evlist *evlist,
 			.nr_entries = nr_entries,
 			.priv	    = evlist,
 		},
+		.min_pcnt = min_pcnt,
 		.env = env,
 	};
 
@@ -1869,6 +1924,7 @@ static int __perf_evlist__tui_browse_hists(struct perf_evlist *evlist,
 
 int perf_evlist__tui_browse_hists(struct perf_evlist *evlist, const char *help,
 				  struct hist_browser_timer *hbt,
+				  float min_pcnt,
 				  struct perf_session_env *env)
 {
 	int nr_entries = evlist->nr_entries;
@@ -1880,7 +1936,8 @@ single_entry:
 		const char *ev_name = perf_evsel__name(first);
 
 		return perf_evsel__hists_browse(first, nr_entries, help,
-						ev_name, false, hbt, env);
+						ev_name, false, hbt, min_pcnt,
+						env);
 	}
 
 	if (symbol_conf.event_group) {
@@ -1896,5 +1953,5 @@ single_entry:
 	}
 
 	return __perf_evlist__tui_browse_hists(evlist, nr_entries, help,
-					       hbt, env);
+					       hbt, min_pcnt, env);
 }
diff --git a/tools/perf/ui/gtk/hists.c b/tools/perf/ui/gtk/hists.c
index 6f259b3d14e2..9708dd5fb8f3 100644
--- a/tools/perf/ui/gtk/hists.c
+++ b/tools/perf/ui/gtk/hists.c
@@ -124,7 +124,8 @@ void perf_gtk__init_hpp(void)
 				perf_gtk__hpp_color_overhead_guest_us;
 }
 
-static void perf_gtk__show_hists(GtkWidget *window, struct hists *hists)
+static void perf_gtk__show_hists(GtkWidget *window, struct hists *hists,
+				 float min_pcnt)
 {
 	struct perf_hpp_fmt *fmt;
 	GType col_types[MAX_COLUMNS];
@@ -189,10 +190,15 @@ static void perf_gtk__show_hists(GtkWidget *window, struct hists *hists)
 	for (nd = rb_first(&hists->entries); nd; nd = rb_next(nd)) {
 		struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);
 		GtkTreeIter iter;
+		float percent = h->stat.period * 100.0 /
+					hists->stats.total_period;
 
 		if (h->filtered)
 			continue;
 
+		if (percent < min_pcnt)
+			continue;
+
 		gtk_list_store_append(store, &iter);
 
 		col_idx = 0;
@@ -222,7 +228,8 @@ static void perf_gtk__show_hists(GtkWidget *window, struct hists *hists)
 
 int perf_evlist__gtk_browse_hists(struct perf_evlist *evlist,
 				  const char *help,
-				  struct hist_browser_timer *hbt __maybe_unused)
+				  struct hist_browser_timer *hbt __maybe_unused,
+				  float min_pcnt)
 {
 	struct perf_evsel *pos;
 	GtkWidget *vbox;
@@ -286,7 +293,7 @@ int perf_evlist__gtk_browse_hists(struct perf_evlist *evlist,
 							GTK_POLICY_AUTOMATIC,
 							GTK_POLICY_AUTOMATIC);
 
-		perf_gtk__show_hists(scrolled_window, hists);
+		perf_gtk__show_hists(scrolled_window, hists, min_pcnt);
 
 		tab_label = gtk_label_new(evname);
 
diff --git a/tools/perf/ui/stdio/hist.c b/tools/perf/ui/stdio/hist.c
index ff1f60cf442e..ae7a75432249 100644
--- a/tools/perf/ui/stdio/hist.c
+++ b/tools/perf/ui/stdio/hist.c
@@ -334,7 +334,7 @@ static int hist_entry__fprintf(struct hist_entry *he, size_t size,
 }
 
 size_t hists__fprintf(struct hists *hists, bool show_header, int max_rows,
-		      int max_cols, FILE *fp)
+		      int max_cols, float min_pcnt, FILE *fp)
 {
 	struct perf_hpp_fmt *fmt;
 	struct sort_entry *se;
@@ -440,10 +440,15 @@ size_t hists__fprintf(struct hists *hists, bool show_header, int max_rows,
 print_entries:
 	for (nd = rb_first(&hists->entries); nd; nd = rb_next(nd)) {
 		struct hist_entry *h = rb_entry(nd, struct hist_entry, rb_node);
+		float percent = h->stat.period * 100.0 /
+					hists->stats.total_period;
 
 		if (h->filtered)
 			continue;
 
+		if (percent < min_pcnt)
+			continue;
+
 		ret += hist_entry__fprintf(h, max_cols, hists, fp);
 
 		if (max_rows && ++nr_rows >= max_rows)
diff --git a/tools/perf/util/hist.h b/tools/perf/util/hist.h
index bd81d799a1bf..2d3790fd99bb 100644
--- a/tools/perf/util/hist.h
+++ b/tools/perf/util/hist.h
@@ -115,7 +115,7 @@ void events_stats__inc(struct events_stats *stats, u32 type);
 size_t events_stats__fprintf(struct events_stats *stats, FILE *fp);
 
 size_t hists__fprintf(struct hists *self, bool show_header, int max_rows,
-		      int max_cols, FILE *fp);
+		      int max_cols, float min_pcnt, FILE *fp);
 
 int hist_entry__inc_addr_samples(struct hist_entry *self, int evidx, u64 addr);
 int hist_entry__annotate(struct hist_entry *self, size_t privsize);
@@ -195,6 +195,7 @@ int hist_entry__tui_annotate(struct hist_entry *he, struct perf_evsel *evsel,
 
 int perf_evlist__tui_browse_hists(struct perf_evlist *evlist, const char *help,
 				  struct hist_browser_timer *hbt,
+				  float min_pcnt,
 				  struct perf_session_env *env);
 int script_browse(const char *script_opt);
 #else
@@ -202,6 +203,7 @@ static inline
 int perf_evlist__tui_browse_hists(struct perf_evlist *evlist __maybe_unused,
 				  const char *help __maybe_unused,
 				  struct hist_browser_timer *hbt __maybe_unused,
+				  float min_pcnt __maybe_unused,
 				  struct perf_session_env *env __maybe_unused)
 {
 	return 0;
@@ -229,12 +231,14 @@ static inline int script_browse(const char *script_opt __maybe_unused)
 
 #ifdef GTK2_SUPPORT
 int perf_evlist__gtk_browse_hists(struct perf_evlist *evlist, const char *help,
-				  struct hist_browser_timer *hbt __maybe_unused);
+				  struct hist_browser_timer *hbt __maybe_unused,
+				  float min_pcnt);
 #else
 static inline
 int perf_evlist__gtk_browse_hists(struct perf_evlist *evlist __maybe_unused,
 				  const char *help __maybe_unused,
-				  struct hist_browser_timer *hbt __maybe_unused)
+				  struct hist_browser_timer *hbt __maybe_unused,
+				  float min_pcnt __maybe_unused)
 {
 	return 0;
 }
-- 
1.7.11.7

[PATCH 2/2] perf top: Add --percent-limit option

[Namhyung Kim]

From: Namhyung Kim <namhyung.kim@lge.com>

The --percent-limit option is for not showing small overheaded entries
in the output.

Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/Documentation/perf-top.txt |  4 ++++
 tools/perf/builtin-top.c              | 17 +++++++++++++++--
 tools/perf/ui/browsers/hists.c        | 16 ++++++++++++++--
 tools/perf/util/top.h                 |  1 +
 4 files changed, 34 insertions(+), 4 deletions(-)

diff --git a/tools/perf/Documentation/perf-top.txt b/tools/perf/Documentation/perf-top.txt
index 9f1a2fe54757..7fdd1909e376 100644
--- a/tools/perf/Documentation/perf-top.txt
+++ b/tools/perf/Documentation/perf-top.txt
@@ -155,6 +155,10 @@ Default is to monitor all CPUS.
 
 	Default: fractal,0.5,callee.
 
+--percent-limit::
+	Do not show entries which have an overhead under that percent.
+	(Default: 0).
+
 INTERACTIVE PROMPTING KEYS
 --------------------------
 
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 19fe25f6e4f0..f036af9b6f09 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -296,7 +296,8 @@ static void perf_top__print_sym_table(struct perf_top *top)
 				     top->print_entries - printed);
 	putchar('\n');
 	hists__fprintf(&top->sym_evsel->hists, false,
-		       top->print_entries - printed, win_width, 0, stdout);
+		       top->print_entries - printed, win_width,
+		       top->min_percent, stdout);
 }
 
 static void prompt_integer(int *target, const char *msg)
@@ -580,7 +581,7 @@ static void *display_thread_tui(void *arg)
 	list_for_each_entry(pos, &top->evlist->entries, node)
 		pos->hists.uid_filter_str = top->record_opts.target.uid_str;
 
-	perf_evlist__tui_browse_hists(top->evlist, help, &hbt, 0,
+	perf_evlist__tui_browse_hists(top->evlist, help, &hbt, top->min_percent,
 				      &top->session->header.env);
 
 	done = 1;
@@ -1021,6 +1022,16 @@ parse_callchain_opt(const struct option *opt, const char *arg, int unset)
 	return record_parse_callchain_opt(opt, arg, unset);
 }
 
+static int
+parse_percent_limit(const struct option *opt, const char *arg,
+		    int unset __maybe_unused)
+{
+	struct perf_top *top = opt->value;
+
+	top->min_percent = strtof(arg, NULL);
+	return 0;
+}
+
 int cmd_top(int argc, const char **argv, const char *prefix __maybe_unused)
 {
 	int status;
@@ -1106,6 +1117,8 @@ int cmd_top(int argc, const char **argv, const char *prefix __maybe_unused)
 	OPT_STRING('M', "disassembler-style", &disassembler_style, "disassembler style",
 		   "Specify disassembler style (e.g. -M intel for intel syntax)"),
 	OPT_STRING('u', "uid", &target->uid_str, "user", "user to profile"),
+	OPT_CALLBACK(0, "percent-limit", &top, "percent",
+		     "Don't show entries under that percent", parse_percent_limit),
 	OPT_END()
 	};
 	const char * const top_usage[] = {
diff --git a/tools/perf/ui/browsers/hists.c b/tools/perf/ui/browsers/hists.c
index 9dfde61505cc..fc0bd3843d34 100644
--- a/tools/perf/ui/browsers/hists.c
+++ b/tools/perf/ui/browsers/hists.c
@@ -310,6 +310,8 @@ static void ui_browser__warn_lost_events(struct ui_browser *browser)
 		"Or reduce the sampling frequency.");
 }
 
+static void hist_browser__update_pcnt_entries(struct hist_browser *hb);
+
 static int hist_browser__run(struct hist_browser *browser, const char *ev_name,
 			     struct hist_browser_timer *hbt)
 {
@@ -333,9 +335,18 @@ static int hist_browser__run(struct hist_browser *browser, const char *ev_name,
 		key = ui_browser__run(&browser->b, delay_secs);
 
 		switch (key) {
-		case K_TIMER:
+		case K_TIMER: {
+			u64 nr_entries;
 			hbt->timer(hbt->arg);
-			ui_browser__update_nr_entries(&browser->b, browser->hists->nr_entries);
+
+			if (browser->min_pcnt) {
+				hist_browser__update_pcnt_entries(browser);
+				nr_entries = browser->nr_pcnt_entries;
+			} else {
+				nr_entries = browser->hists->nr_entries;
+			}
+
+			ui_browser__update_nr_entries(&browser->b, nr_entries);
 
 			if (browser->hists->stats.nr_lost_warned !=
 			    browser->hists->stats.nr_events[PERF_RECORD_LOST]) {
@@ -347,6 +358,7 @@ static int hist_browser__run(struct hist_browser *browser, const char *ev_name,
 			hists__browser_title(browser->hists, title, sizeof(title), ev_name);
 			ui_browser__show_title(&browser->b, title);
 			continue;
+		}
 		case 'D': { /* Debug */
 			static int seq;
 			struct hist_entry *h = rb_entry(browser->b.top,
diff --git a/tools/perf/util/top.h b/tools/perf/util/top.h
index f0a862539ba9..df46be93d902 100644
--- a/tools/perf/util/top.h
+++ b/tools/perf/util/top.h
@@ -36,6 +36,7 @@ struct perf_top {
 	int		   realtime_prio;
 	int		   sym_pcnt_filter;
 	const char	   *sym_filter;
+	float		   min_percent;
 };
 
 size_t perf_top__header_snprintf(struct perf_top *top, char *bf, size_t size);
-- 
1.7.11.7

Re: [PATCH 1/2] perf report: Add --percent-limit option

[Pekka Enberg]

On Mon, May 13, 2013 at 11:41 AM, Namhyung Kim <namhyung@kernel.org> wrote:
> From: Namhyung Kim <namhyung.kim@lge.com>
>
> The --percent-limit option is for not showing small overheaded entries
> in the output.  Maybe we want to set a certain default value like 0.1.
>
> Cc: Andi Kleen <andi@firstfloor.org>
> Signed-off-by: Namhyung Kim <namhyung@kernel.org>

Acked-by: Pekka Enberg <penberg@kernel.org>

Re: [PATCH 2/2] perf top: Add --percent-limit option

[Pekka Enberg]

On Mon, May 13, 2013 at 11:41 AM, Namhyung Kim <namhyung@kernel.org> wrote:
> From: Namhyung Kim <namhyung.kim@lge.com>
>
> The --percent-limit option is for not showing small overheaded entries
> in the output.
>
> Cc: Andi Kleen <andi@firstfloor.org>
> Signed-off-by: Namhyung Kim <namhyung@kernel.org>

Acked-by: Pekka Enberg <penberg@kernel.org>

Re: [PATCH 1/2] perf report: Add --percent-limit option

[Jiri Olsa]

On Mon, May 13, 2013 at 05:41:42PM +0900, Namhyung Kim wrote:
> From: Namhyung Kim <namhyung.kim@lge.com>
> 
> The --percent-limit option is for not showing small overheaded entries
> in the output.  Maybe we want to set a certain default value like 0.1.

hi,
can't apply this on acme's perf/core nor latest tip
What is this based on? Maybe you could push the branch out? ;-)

thanks,
jirka

Re: [PATCH 1/2] perf report: Add --percent-limit option

[Andi Kleen]

On Mon, May 13, 2013 at 05:41:42PM +0900, Namhyung Kim wrote:
> From: Namhyung Kim <namhyung.kim@lge.com>
> 
> The --percent-limit option is for not showing small overheaded entries
> in the output.  Maybe we want to set a certain default value like 0.1.
> 
> Cc: Andi Kleen <andi@firstfloor.org>

I like the option, but 0 is not a good default.
Make it 1 or something.

Perhaps a better heuristic would be 
percent < threshold || samples < sample-threshold
with sample-threshold being several hundred at least.

A very small number of hits on something is usually quite much useless,
unless your original event was extremly rare in the beginning
(but then it's unclear if the profile is any useful)

-Andi

Re: [PATCH 1/2] perf report: Add --percent-limit option

[Namhyung Kim]

Hi Pekka,

On Mon, 13 May 2013 11:58:22 +0300, Pekka Enberg wrote:
> On Mon, May 13, 2013 at 11:41 AM, Namhyung Kim <namhyung@kernel.org> wrote:
>> From: Namhyung Kim <namhyung.kim@lge.com>
>>
>> The --percent-limit option is for not showing small overheaded entries
>> in the output.  Maybe we want to set a certain default value like 0.1.
>>
>> Cc: Andi Kleen <andi@firstfloor.org>
>> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
>
> Acked-by: Pekka Enberg <penberg@kernel.org>

Thanks and sorry for missing you on CC list.
Namhyung

Re: [PATCH 1/2] perf report: Add --percent-limit option

[Namhyung Kim]

Hi Jiri,

On Mon, 13 May 2013 15:20:29 +0200, Jiri Olsa wrote:
> On Mon, May 13, 2013 at 05:41:42PM +0900, Namhyung Kim wrote:
>> From: Namhyung Kim <namhyung.kim@lge.com>
>> 
>> The --percent-limit option is for not showing small overheaded entries
>> in the output.  Maybe we want to set a certain default value like 0.1.
>
> hi,
> can't apply this on acme's perf/core nor latest tip
> What is this based on? Maybe you could push the branch out? ;-)

Oops, I wanted to make it independent to other patches, but it seemed I
failed. :)

It's on top on acme/perf/core but also depends on my other works.  I'll
resend the patches in a set and push the branch soon.

Thanks,
Namhyung

Re: [PATCH 1/2] perf report: Add --percent-limit option

[Namhyung Kim]

Hi Andi,

On Mon, 13 May 2013 16:11:17 +0200, Andi Kleen wrote:
> On Mon, May 13, 2013 at 05:41:42PM +0900, Namhyung Kim wrote:
>> From: Namhyung Kim <namhyung.kim@lge.com>
>> 
>> The --percent-limit option is for not showing small overheaded entries
>> in the output.  Maybe we want to set a certain default value like 0.1.
>> 
>> Cc: Andi Kleen <andi@firstfloor.org>
>
> I like the option, but 0 is not a good default.
> Make it 1 or something.

Thanks.  I just wanted to reserve same behavior since I didn't know
what's the reasonable default value.  We might use a config variable for
this to customize the default value.

>
> Perhaps a better heuristic would be 
> percent < threshold || samples < sample-threshold
> with sample-threshold being several hundred at least.
>
> A very small number of hits on something is usually quite much useless,
> unless your original event was extremly rare in the beginning
> (but then it's unclear if the profile is any useful)

Looks reasonable, but I know there's also some users who use the perf
tools lightly.  A several hundreds sample-threshold looks too harsh to
them IMHO.  In addition, it should handle tracepoints.

Thanks,
Namhyung