perf diff: Add -p option to display period values for hist entries

Adding -p option to show period values for both compared hist entries.
Showing hist column PERF_HPP__PERIOD and newly added hist column
PERF_HPP__PERIOD_BASELINE.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1349448287-18919-6-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/ui/hist.c b/tools/perf/ui/hist.c
index 522b4ec..2fadaff 100644
--- a/tools/perf/ui/hist.c
+++ b/tools/perf/ui/hist.c
@@ -228,6 +228,26 @@
 	return scnprintf(hpp->buf, hpp->size, fmt, he->stat.period);
 }
 
+static int hpp__header_period_baseline(struct perf_hpp *hpp)
+{
+	const char *fmt = symbol_conf.field_sep ? "%s" : "%12s";
+
+	return scnprintf(hpp->buf, hpp->size, fmt, "Period Base");
+}
+
+static int hpp__width_period_baseline(struct perf_hpp *hpp __maybe_unused)
+{
+	return 12;
+}
+
+static int hpp__entry_period_baseline(struct perf_hpp *hpp, struct hist_entry *he)
+{
+	struct hist_entry *pair = he->pair;
+	u64 period = pair ? pair->stat.period : 0;
+	const char *fmt = symbol_conf.field_sep ? "%" PRIu64 : "%12" PRIu64;
+
+	return scnprintf(hpp->buf, hpp->size, fmt, period);
+}
 static int hpp__header_delta(struct perf_hpp *hpp)
 {
 	const char *fmt = symbol_conf.field_sep ? "%s" : "%7s";
@@ -359,6 +379,7 @@
 	{ .cond = false, HPP__COLOR_PRINT_FNS(overhead_guest_us) },
 	{ .cond = false, HPP__PRINT_FNS(samples) },
 	{ .cond = false, HPP__PRINT_FNS(period) },
+	{ .cond = false, HPP__PRINT_FNS(period_baseline) },
 	{ .cond = false, HPP__PRINT_FNS(delta) },
 	{ .cond = false, HPP__PRINT_FNS(ratio) },
 	{ .cond = false, HPP__PRINT_FNS(wdiff) },