It calculates IPC from the cycles and instruction counts and compares
it with the shadow stat for both global aggregation (default) and no
aggregation mode.
$ perf stat -a -A -e cycles,instructions sleep 1
Performance counter stats for 'system wide':
CPU0 39,580,880 cycles
CPU1 45,426,945 cycles
CPU2 31,151,685 cycles
CPU3 55,167,421 cycles
CPU0 17,073,564 instructions # 0.43 insn per cycle
CPU1 34,955,764 instructions # 0.77 insn per cycle
CPU2 15,688,459 instructions # 0.50 insn per cycle
CPU3 34,699,217 instructions # 0.63 insn per cycle
1.003275495 seconds time elapsed
In this example, the 'insn per cycle' should be matched to the number
for each cpu. For CPU2, 0.50 = 15,688,459 / 31,151,685 .
Signed-off-by: Namhyung Kim <[email protected]>
---
tools/perf/tests/shell/stat+shadow_stat.sh | 80 ++++++++++++++++++++++
1 file changed, 80 insertions(+)
create mode 100755 tools/perf/tests/shell/stat+shadow_stat.sh
diff --git a/tools/perf/tests/shell/stat+shadow_stat.sh
b/tools/perf/tests/shell/stat+shadow_stat.sh
new file mode 100755
index 000000000000..249dfe48cf6a
--- /dev/null
+++ b/tools/perf/tests/shell/stat+shadow_stat.sh
@@ -0,0 +1,80 @@
+#!/bin/sh
+# perf stat metrics (shadow stat) test
+# SPDX-License-Identifier: GPL-2.0
+
+set -e
+
+# skip if system-wide mode is forbidden
+perf stat -a true > /dev/null 2>&1 || exit 2
+
+test_global_aggr()
+{
+ local cyc
+
+ perf stat -a --no-big-num -e cycles,instructions sleep 1 2>&1 | \
+ grep -e cycles -e instructions | \
+ while read num evt hash ipc rest
+ do
+ # skip not counted events
+ if [[ $num == "<not" ]]; then
+ continue
+ fi
+
+ # save cycles count
+ if [[ $evt == "cycles" ]]; then
+ cyc=$num
+ continue
+ fi
+
+ # skip if no cycles
+ if [[ -z $cyc ]]; then
+ continue
+ fi
+
+ # use printf for rounding and a leading zero
+ local res=`printf "%.2f" $(echo "scale=6; $num / $cyc" | bc -q)`
+ if [[ $ipc != $res ]]; then
+ echo "IPC is different: $res != $ipc ($num / $cyc)"
+ exit 1
+ fi
+ done
+}
+
+test_no_aggr()
+{
+ declare -A results
+
+ perf stat -a -A --no-big-num -e cycles,instructions sleep 1 2>&1 | \
+ grep ^CPU | \
+ while read cpu num evt hash ipc rest
+ do
+ # skip not counted events
+ if [[ $num == "<not" ]]; then
+ continue
+ fi
+
+ # save cycles count
+ if [[ $evt == "cycles" ]]; then
+ results[$cpu]=$num
+ continue
+ fi
+
+ # skip if no cycles
+ local cyc=${results[$cpu]}
+ if [[ -z $cyc ]]; then
+ continue
+ fi
+
+ # use printf for rounding and a leading zero
+ local res=`printf "%.2f" $(echo "scale=6; $num / $cyc" | bc -q)`
+ if [[ $ipc != $res ]]; then
+ echo "IPC is different for $cpu: $res != $ipc ($num /
$cyc)"
+ exit 1
+ fi
+ done
+}
+
+test_global_aggr
+test_no_aggr
+
+exit 0
--
2.29.2.454.gaff20da3a2-goog
