[PATCH 8/8] perf script: Add stat-cpi.py script

[Jiri Olsa <jolsa@kernel.org>]

Adding stat-cpi.py as an example of how to do stat scripting.
It computes the CPI metrics from cycles and instructions
events.

Following stat record/report/script combinations could be used:

- get CPI for given workload

    $ perf stat -e cycles,instructions record ls

    SNIP

     Performance counter stats for 'ls':

             2,904,431      cycles
             3,346,878      instructions              #    1.15  insns per cycle

           0.001782686 seconds time elapsed

    $ perf script -s ./scripts/python/stat-cpi.py
           0.001783: cpu -1, thread -1 -> cpi 0.867803 (2904431/3346878)

    $ perf stat -e cycles,instructions record ls | perf script -s ./scripts/python/stat-cpi.py

    SNIP

           0.001730: cpu -1, thread -1 -> cpi 0.869026 (2928292/3369627)

- get CPI systemwide:

    $ perf stat -e cycles,instructions -a -I 1000 record sleep 3
    #           time             counts unit events
         1.000158618        594,274,711      cycles                     (100.00%)
         1.000158618        441,898,250      instructions
         2.000350973        567,649,705      cycles                     (100.00%)
         2.000350973        432,669,206      instructions
         3.000559210        561,940,430      cycles                     (100.00%)
         3.000559210        420,403,465      instructions
         3.000670798            780,105      cycles                     (100.00%)
         3.000670798            326,516      instructions

    $ perf script -s ./scripts/python/stat-cpi.py
           1.000159: cpu -1, thread -1 -> cpi 1.344823 (594274711/441898250)
           2.000351: cpu -1, thread -1 -> cpi 1.311972 (567649705/432669206)
           3.000559: cpu -1, thread -1 -> cpi 1.336669 (561940430/420403465)
           3.000671: cpu -1, thread -1 -> cpi 2.389178 (780105/326516)

    $ perf stat -e cycles,instructions -a -I 1000 record sleep 3 | perf script -s ./scripts/python/stat-cpi.py
           1.000202: cpu -1, thread -1 -> cpi 1.035091 (940778881/908885530)
           2.000392: cpu -1, thread -1 -> cpi 1.442600 (627493992/434974455)
           3.000545: cpu -1, thread -1 -> cpi 1.353612 (741463930/547766890)
           3.000622: cpu -1, thread -1 -> cpi 2.642110 (784083/296764)

Tested-by: Kan Liang <kan.liang@intel.com>
Link: http://lkml.kernel.org/n/tip-15vwwb4yea15wzz6bqbxdpc0@git.kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
 tools/perf/scripts/python/stat-cpi.py | 77 +++++++++++++++++++++++++++++++++++
 1 file changed, 77 insertions(+)
 create mode 100644 tools/perf/scripts/python/stat-cpi.py

diff --git a/tools/perf/scripts/python/stat-cpi.py b/tools/perf/scripts/python/stat-cpi.py
new file mode 100644
index 000000000000..8b60f343dd07
--- /dev/null
+++ b/tools/perf/scripts/python/stat-cpi.py
@@ -0,0 +1,77 @@
+#!/usr/bin/env python
+
+data    = {}
+times   = []
+threads = []
+cpus    = []
+
+def get_key(time, event, cpu, thread):
+    return "%d-%s-%d-%d" % (time, event, cpu, thread)
+
+def store_key(time, cpu, thread):
+    if (time not in times):
+        times.append(time)
+
+    if (cpu not in cpus):
+        cpus.append(cpu)
+
+    if (thread not in threads):
+        threads.append(thread)
+
+def store(time, event, cpu, thread, val, ena, run):
+    #print "event %s cpu %d, thread %d, time %d, val %d, ena %d, run %d" % \
+    #      (event, cpu, thread, time, val, ena, run)
+
+    store_key(time, cpu, thread)
+    key = get_key(time, event, cpu, thread)
+    data[key] = [ val, ena, run]
+
+def get(time, event, cpu, thread):
+    key = get_key(time, event, cpu, thread)
+    return data[key][0]
+
+def stat__cycles_k(cpu, thread, time, val, ena, run):
+    store(time, "cycles", cpu, thread, val, ena, run);
+
+def stat__instructions_k(cpu, thread, time, val, ena, run):
+    store(time, "instructions", cpu, thread, val, ena, run);
+
+def stat__cycles_u(cpu, thread, time, val, ena, run):
+    store(time, "cycles", cpu, thread, val, ena, run);
+
+def stat__instructions_u(cpu, thread, time, val, ena, run):
+    store(time, "instructions", cpu, thread, val, ena, run);
+
+def stat__cycles(cpu, thread, time, val, ena, run):
+    store(time, "cycles", cpu, thread, val, ena, run);
+
+def stat__instructions(cpu, thread, time, val, ena, run):
+    store(time, "instructions", cpu, thread, val, ena, run);
+
+def stat__interval(time):
+    for cpu in cpus:
+        for thread in threads:
+            cyc = get(time, "cycles", cpu, thread)
+            ins = get(time, "instructions", cpu, thread)
+            cpi = 0
+
+            if ins != 0:
+                cpi = cyc/float(ins)
+
+            print "%15f: cpu %d, thread %d -> cpi %f (%d/%d)" % (time/(float(1000000000)), cpu, thread, cpi, cyc, ins)
+
+def trace_end():
+    pass
+# XXX trace_end callback could be used as an alternative place
+#     to compute same values as in the script above:
+#
+#    for time in times:
+#        for cpu in cpus:
+#            for thread in threads:
+#                cyc = get(time, "cycles", cpu, thread)
+#                ins = get(time, "instructions", cpu, thread)
+#
+#                if ins != 0:
+#                    cpi = cyc/float(ins)
+#
+#                print "time %.9f, cpu %d, thread %d -> cpi %f" % (time/(float(1000000000)), cpu, thread, cpi)
-- 
2.4.3