[PATCH v5 4/7] perf report: Refactor the branch info printing code

Jin Yao
2017-04-19T07:50:44Z

The branch info such as predicted/cycles/... are printed at the
callchain entries.

For example: perf report --branch-history --no-children --stdio

--1.07%--main div.c:39 (predicted:52.4% cycles:1 iterations:17)
main div.c:44 (predicted:52.4% cycles:1)
main div.c:42 (cycles:2)
compute_flag div.c:28 (cycles:2)
compute_flag div.c:27 (cycles:1)
rand rand.c:28 (cycles:1)
rand rand.c:28 (cycles:1)
__random random.c:298 (cycles:1)
__random random.c:297 (cycles:1)
__random random.c:295 (cycles:1)
__random random.c:295 (cycles:1)
__random random.c:295 (cycles:1)

But the current code is difficult to maintain and extend. This patch
refactors the code for easy maintenance.

Change log
----------

v5: It's a new patch in v5 patch series.

Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
---
tools/perf/util/callchain.c | 106 +++++++++++++++++++-------------------------
1 file changed, 45 insertions(+), 61 deletions(-)

diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c
index 2e5eff5..8cae8a6 100644
--- a/tools/perf/util/callchain.c
+++ b/tools/perf/util/callchain.c
@@ -1105,83 +1105,67 @@ int callchain_branch_counts(struct callchain_root *root,
cycles_count);
}

+static int count_pri64_printf(int index, const char *str, u64 value,
+ char *bf, int bfsize)
+{
+ int printed;
+
+ printed = scnprintf(bf, bfsize,
+ "%s%s:%" PRId64 "",
+ (index) ? " " : " (", str, value);
+
+ return printed;
+}
+
+static int count_float_printf(int index, const char *str, float value,
+ char *bf, int bfsize)
+{
+ int printed;
+
+ printed = scnprintf(bf, bfsize,
+ "%s%s:%.1f%%",
+ (index) ? " " : " (", str, value);
+
+ return printed;
+}
+
static int counts_str_build(char *bf, int bfsize,
u64 branch_count, u64 predicted_count,
u64 abort_count, u64 cycles_count,
u64 iter_count, u64 samples_count)
{
- double predicted_percent = 0.0;
- const char *null_str = "";
- char iter_str[32];
- char cycle_str[32];
- char *istr, *cstr;
u64 cycles;
+ int printed = 0, i = 0;

if (branch_count == 0)
return scnprintf(bf, bfsize, " (calltrace)");

cycles = cycles_count / branch_count;
+ if (cycles)
+ printed += count_pri64_printf(i++, "cycles",
+ cycles,
+ bf + printed, bfsize - printed);

- if (iter_count && samples_count) {
- if (cycles > 0)
- scnprintf(iter_str, sizeof(iter_str),
- " iterations:%" PRId64 "",
- iter_count / samples_count);
- else
- scnprintf(iter_str, sizeof(iter_str),
- "iterations:%" PRId64 "",
- iter_count / samples_count);
- istr = iter_str;
- } else
- istr = (char *)null_str;
-
- if (cycles > 0) {
- scnprintf(cycle_str, sizeof(cycle_str),
- "cycles:%" PRId64 "", cycles);
- cstr = cycle_str;
- } else
- cstr = (char *)null_str;
+ if (iter_count && samples_count)
+ printed += count_pri64_printf(i++, "iterations",
+ iter_count / samples_count,
+ bf + printed, bfsize - printed);

- predicted_percent = predicted_count * 100.0 / branch_count;
+ if (predicted_count < branch_count)
+ printed += count_float_printf(i++, "predicted",
+ predicted_count * 100.0 / branch_count,
+ bf + printed, bfsize - printed);

- if ((predicted_count == branch_count) && (abort_count == 0)) {
- if ((cycles > 0) || (istr != (char *)null_str))
- return scnprintf(bf, bfsize, " (%s%s)", cstr, istr);
- else
- return scnprintf(bf, bfsize, "%s", (char *)null_str);
- }
-
- if ((predicted_count < branch_count) && (abort_count == 0)) {
- if ((cycles > 0) || (istr != (char *)null_str))
- return scnprintf(bf, bfsize,
- " (predicted:%.1f%% %s%s)",
- predicted_percent, cstr, istr);
- else {
- return scnprintf(bf, bfsize,
- " (predicted:%.1f%%)",
- predicted_percent);
- }
- }
-
- if ((predicted_count == branch_count) && (abort_count > 0)) {
- if ((cycles > 0) || (istr != (char *)null_str))
- return scnprintf(bf, bfsize,
- " (abort:%" PRId64 " %s%s)",
- abort_count, cstr, istr);
- else
- return scnprintf(bf, bfsize,
- " (abort:%" PRId64 ")",
- abort_count);
- }
+ if (abort_count)
+ printed += count_float_printf(i++, "abort",
+ abort_count * 100.0 / branch_count,
+ bf + printed, bfsize - printed);

- if ((cycles > 0) || (istr != (char *)null_str))
- return scnprintf(bf, bfsize,
- " (predicted:%.1f%% abort:%" PRId64 " %s%s)",
- predicted_percent, abort_count, cstr, istr);
+ if (i)
+ return scnprintf(bf + printed, bfsize - printed, ")");

- return scnprintf(bf, bfsize,
- " (predicted:%.1f%% abort:%" PRId64 ")",
- predicted_percent, abort_count);
+ bf[0] = 0;
+ return 0;
}

static int callchain_counts_printf(FILE *fp, char *bf, int bfsize,
--
2.7.4