[PATCH 83/86] perf report: Refactor the branch info printing code

Arnaldo Carvalho de Melo
2017-07-19T14:38:21Z

From: Jin Yao <yao.jin@linux.intel.com>

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:

v6: 1. Put the multiline condition code into {} brackets in
counts_str_build()

2. Keep the original display order, that is:
predicted, abort, cycles, iterations

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

Signed-off-by: Yao Jin <yao.jin@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1500379995-6449-5-git-send-email-yao.jin@linux.intel.com
[ Don't use 'index' as a name for a variable, it shadows a globa decl in older distros ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/util/callchain.c | 100 ++++++++++++++++++--------------------------
1 file changed, 41 insertions(+), 59 deletions(-)

diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c
index b4204b43ed58..917f4d6510ae 100644
--- a/tools/perf/util/callchain.c
+++ b/tools/perf/util/callchain.c
@@ -1214,83 +1214,65 @@ int callchain_branch_counts(struct callchain_root *root,
cycles_count);
}

+static int count_pri64_printf(int idx, const char *str, u64 value, char *bf, int bfsize)
+{
+ int printed;
+
+ printed = scnprintf(bf, bfsize, "%s%s:%" PRId64 "", (idx) ? " " : " (", str, value);
+
+ return printed;
+}
+
+static int count_float_printf(int idx, const char *str, float value, char *bf, int bfsize)
+{
+ int printed;
+
+ printed = scnprintf(bf, bfsize, "%s%s:%.1f%%", (idx) ? " " : " (", 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 (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;
-
- 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 (abort_count) {
+ printed += count_float_printf(i++, "abort",
+ abort_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,
- " (predicted:%.1f%% %s%s)",
- predicted_percent, cstr, istr);
- else {
- return scnprintf(bf, bfsize,
- " (predicted:%.1f%%)",
- predicted_percent);
- }
+ cycles = cycles_count / branch_count;
+ if (cycles) {
+ printed += count_pri64_printf(i++, "cycles",
+ cycles,
+ bf + printed, bfsize - printed);
}

- 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 (iter_count && samples_count) {
+ printed += count_pri64_printf(i++, "iterations",
+ iter_count / samples_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,
--
2.9.4