[PATCH v3 3/5] perf tools: Fix dynamic sort keys to sort properly

Namhyung Kim
2016-01-06T00:56:09Z

Currently, the dynamic sort keys compares trace data using memcmp().
But for output sorting, it should check data size and compare by word.
Also it sorted strings in reverse order, fix it.

Before)

$ perf report -F overhead -s prev_pid,next_pid
...
# Overhead prev_pid next_pid
# ........ .......... ..........
#
0.39% 490 0
9.12% 225 0
0.04% 224 0
0.51% 731 189
0.08% 731 3
0.12% 731 0
4.82% 729 0
0.08% 1229 0
0.20% 715 0
4.78% 189 225
...

After)

$ perf report -F overhead -s prev_pid,next_pid
...
# Overhead prev_pid next_pid
# ........ .......... ..........
#
0.43% 0 7
0.04% 0 11
0.04% 0 12
0.08% 0 14
0.04% 0 17
0.08% 0 19
0.04% 0 22
0.04% 0 27
0.04% 0 37
0.04% 0 42
...

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
tools/perf/util/sort.c | 47 ++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 46 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/sort.c b/tools/perf/util/sort.c
index 9618a64875c0..264d2b630549 100644
--- a/tools/perf/util/sort.c
+++ b/tools/perf/util/sort.c
@@ -1798,6 +1798,51 @@ static int64_t __sort__hde_cmp(struct perf_hpp_fmt *fmt,
return memcmp(a->raw_data + offset, b->raw_data + offset, size);
}

+static int64_t __sort__hde_sort(struct perf_hpp_fmt *fmt,
+ struct hist_entry *a, struct hist_entry *b)
+{
+ struct hpp_dynamic_entry *hde;
+ struct format_field *field;
+ unsigned offset, size;
+ int64_t *a64, *b64;
+ int32_t *a32, *b32;
+ int16_t *a16, *b16;
+
+ hde = container_of(fmt, struct hpp_dynamic_entry, hpp);
+
+ field = hde->field;
+ if (field->flags & FIELD_IS_DYNAMIC) {
+ unsigned long long dyn;
+
+ pevent_read_number_field(field, a->raw_data, &dyn);
+ offset = dyn & 0xffff;
+ size = (dyn >> 16) & 0xffff;
+ } else {
+ offset = field->offset;
+ size = field->size;
+ }
+
+ if (field->flags & FIELD_IS_STRING)
+ return strcmp(b->raw_data + offset, a->raw_data + offset);
+
+ switch (size) {
+ case 8:
+ a64 = a->raw_data + offset;
+ b64 = b->raw_data + offset;
+ return *b64 - *a64;
+ case 4:
+ a32 = a->raw_data + offset;
+ b32 = b->raw_data + offset;
+ return *b32 - *a32;
+ case 2:
+ a16 = a->raw_data + offset;
+ b16 = b->raw_data + offset;
+ return *b16 - *a16;
+ default:
+ return memcmp(b->raw_data + offset, a->raw_data + offset, size);
+ }
+}
+
bool perf_hpp__is_dynamic_entry(struct perf_hpp_fmt *fmt)
{
return fmt->cmp == __sort__hde_cmp;
@@ -1826,7 +1871,7 @@ __alloc_dynamic_entry(struct perf_evsel *evsel, struct format_field *field)

hde->hpp.cmp = __sort__hde_cmp;
hde->hpp.collapse = __sort__hde_cmp;
- hde->hpp.sort = __sort__hde_cmp;
+ hde->hpp.sort = __sort__hde_sort;

INIT_LIST_HEAD(&hde->hpp.list);
INIT_LIST_HEAD(&hde->hpp.sort_list);
--
2.6.4