[PATCH v3 2/6] perf report: Caculate and return the branch flag counting

From: Jin Yao
Date: Tue Oct 25 2016 - 21:14:42 EST


Create some branch counters in per callchain list entry. Each counter
is for a branch flag. For example, predicted_count counts all the
*predicted* branches. The counters get updated by processing the
callchain cursor nodes.

It also provides functions to retrieve or print the values of counters
in callchain list.

Besides the counting for branch flags, it also counts and returns the
number of removed loops.

Signed-off-by: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
---
tools/perf/util/callchain.c | 184 +++++++++++++++++++++++++++++++++++++++++++-
tools/perf/util/callchain.h | 13 ++++
2 files changed, 196 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c
index 7857494..060121c 100644
--- a/tools/perf/util/callchain.c
+++ b/tools/perf/util/callchain.c
@@ -440,6 +440,20 @@ fill_node(struct callchain_node *node, struct callchain_cursor *cursor)
call->ip = cursor_node->ip;
call->ms.sym = cursor_node->sym;
call->ms.map = cursor_node->map;
+
+ if (cursor_node->branch) {
+ call->branch_count = 1;
+
+ if (cursor_node->branch_flags.predicted)
+ call->predicted_count = 1;
+
+ if (cursor_node->branch_flags.abort)
+ call->abort_count = 1;
+
+ call->cycles_count = cursor_node->branch_flags.cycles;
+ call->removed_loop = cursor_node->removed_loop;
+ }
+
list_add_tail(&call->list, &node->val);

callchain_cursor_advance(cursor);
@@ -499,8 +513,22 @@ static enum match_result match_chain(struct callchain_cursor_node *node,
right = node->ip;
}

- if (left == right)
+ if (left == right) {
+ if (node->branch) {
+ cnode->branch_count++;
+
+ if (node->branch_flags.predicted)
+ cnode->predicted_count++;
+
+ if (node->branch_flags.abort)
+ cnode->abort_count++;
+
+ cnode->cycles_count += node->branch_flags.cycles;
+ cnode->removed_loop += node->removed_loop;
+ }
+
return MATCH_EQ;
+ }

return left > right ? MATCH_GT : MATCH_LT;
}
@@ -948,6 +976,160 @@ int callchain_node__fprintf_value(struct callchain_node *node,
return 0;
}

+static void callchain_counts_value(struct callchain_node *node,
+ u64 *branch_count, u64 *predicted_count,
+ u64 *abort_count, u64 *cycles_count)
+{
+ struct callchain_list *clist;
+
+ list_for_each_entry(clist, &node->val, list) {
+ if (branch_count)
+ *branch_count += clist->branch_count;
+
+ if (predicted_count)
+ *predicted_count += clist->predicted_count;
+
+ if (abort_count)
+ *abort_count += clist->abort_count;
+
+ if (cycles_count)
+ *cycles_count += clist->cycles_count;
+ }
+}
+
+static int callchain_node_branch_counts_cumul(struct callchain_node *node,
+ u64 *branch_count,
+ u64 *predicted_count,
+ u64 *abort_count,
+ u64 *cycles_count)
+{
+ struct callchain_node *child;
+ struct rb_node *n;
+
+ n = rb_first(&node->rb_root_in);
+ while (n) {
+ child = rb_entry(n, struct callchain_node, rb_node_in);
+ n = rb_next(n);
+
+ callchain_node_branch_counts_cumul(child, branch_count,
+ predicted_count,
+ abort_count,
+ cycles_count);
+
+ callchain_counts_value(child, branch_count,
+ predicted_count, abort_count,
+ cycles_count);
+ }
+
+ return 0;
+}
+
+int callchain_branch_counts(struct callchain_root *root,
+ u64 *branch_count, u64 *predicted_count,
+ u64 *abort_count, u64 *cycles_count)
+{
+ if (branch_count)
+ *branch_count = 0;
+
+ if (predicted_count)
+ *predicted_count = 0;
+
+ if (abort_count)
+ *abort_count = 0;
+
+ if (cycles_count)
+ *cycles_count = 0;
+
+ return callchain_node_branch_counts_cumul(&root->node,
+ branch_count,
+ predicted_count,
+ abort_count,
+ cycles_count);
+}
+
+static int callchain_counts_printf(FILE *fp, char *bf, int bfsize,
+ u64 branch_count, u64 predicted_count,
+ u64 abort_count, u64 cycles_count,
+ int removed_loop)
+{
+ double predicted_percent = 0.0;
+ const char *null_str = "";
+ char removed_str[32];
+ char *str;
+ u64 cycles = 0;
+
+ if (branch_count == 0) {
+ if (fp)
+ return fprintf(fp, " (calltrace)");
+
+ return scnprintf(bf, bfsize, " (calltrace)");
+ }
+
+ if (removed_loop) {
+ scnprintf(removed_str, sizeof(removed_str),
+ ", removed loops:%d", removed_loop);
+ str = removed_str;
+ } else
+ str = (char *)null_str;
+
+ predicted_percent = predicted_count * 100.0 / branch_count;
+ cycles = cycles_count / branch_count;
+
+ if ((predicted_percent >= 100.0) && (abort_count == 0)) {
+ if (fp)
+ return fprintf(fp, " (cycles:%" PRId64 "%s)",
+ cycles, str);
+
+ return scnprintf(bf, bfsize, " (cycles:%" PRId64 "%s)",
+ cycles, str);
+ }
+
+ if ((predicted_percent < 100.0) && (abort_count == 0)) {
+ if (fp)
+ return fprintf(fp,
+ " (predicted:%.1f%%, cycles:%" PRId64 "%s)",
+ predicted_percent, cycles, str);
+
+ return scnprintf(bf, bfsize,
+ " (predicted:%.1f%%, cycles:%" PRId64 "%s)",
+ predicted_percent, cycles, str);
+ }
+
+ if (fp)
+ return fprintf(fp,
+ " (predicted:%.1f%%, abort:%" PRId64 ", cycles:%" PRId64 "%s)",
+ predicted_percent, abort_count, cycles, str);
+
+ return scnprintf(bf, bfsize,
+ " (predicted:%.1f%%, abort:%" PRId64 ", cycles:%" PRId64 "%s)",
+ predicted_percent, abort_count, cycles, str);
+}
+
+int callchain_list_counts__printf_value(struct callchain_node *node,
+ struct callchain_list *clist,
+ FILE *fp, char *bf, int bfsize)
+{
+ u64 branch_count, predicted_count;
+ u64 abort_count, cycles_count;
+ int removed_loop = 0;
+
+ branch_count = clist->branch_count;
+ predicted_count = clist->predicted_count;
+ abort_count = clist->abort_count;
+ cycles_count = clist->cycles_count;
+
+ if (node) {
+ struct callchain_list *call;
+
+ list_for_each_entry(call, &node->val, list)
+ removed_loop += call->removed_loop;
+ }
+
+ return callchain_counts_printf(fp, bf, bfsize, branch_count,
+ predicted_count, abort_count,
+ cycles_count, removed_loop);
+}
+
static void free_callchain_node(struct callchain_node *node)
{
struct callchain_list *list, *tmp;
diff --git a/tools/perf/util/callchain.h b/tools/perf/util/callchain.h
index a16da59..f6a870c 100644
--- a/tools/perf/util/callchain.h
+++ b/tools/perf/util/callchain.h
@@ -115,6 +115,11 @@ struct callchain_list {
bool unfolded;
bool has_children;
};
+ u64 branch_count;
+ u64 predicted_count;
+ u64 abort_count;
+ u64 cycles_count;
+ int removed_loop;
char *srcline;
struct list_head list;
};
@@ -266,8 +271,16 @@ char *callchain_node__scnprintf_value(struct callchain_node *node,
int callchain_node__fprintf_value(struct callchain_node *node,
FILE *fp, u64 total);

+int callchain_list_counts__printf_value(struct callchain_node *node,
+ struct callchain_list *clist,
+ FILE *fp, char *bf, int bfsize);
+
void free_callchain(struct callchain_root *root);
void decay_callchain(struct callchain_root *root);
int callchain_node__make_parent_list(struct callchain_node *node);

+int callchain_branch_counts(struct callchain_root *root,
+ u64 *branch_count, u64 *predicted_count,
+ u64 *abort_count, u64 *cycles_count);
+
#endif /* __PERF_CALLCHAIN_H */
--
2.7.4