Re: [PATCH V2] perf script: add script to profile and resolve physical mem type

[Philippe Ombredanne]

Dear Kan,

On Wed, Jan 3, 2018 at 9:20 PM, Liang, Kan <kan.liang@xxxxxxxxx> wrote:
> Hi Stephane and Andi,
>
> Could you please review the script?
>
> If it's OK for you, could you please Ack/Review this?
>
> Thanks,
> Kan
>
>>
>> From: Kan Liang <Kan.liang@xxxxxxxxx>
>>
>> There could be different types of memory in the system. E.g normal
>> System Memory, Persistent Memory. To understand how the workload maps
>> to
>> those memories, it's important to know the I/O statistics of them.
>> Perf can collect physical addresses, but those are raw data.
>> It still needs extra work to resolve the physical addresses.
>> Provide a script to facilitate the physical addresses resolving and
>> I/O statistics.
>>
>> Profile with MEM_INST_RETIRED.ALL_LOADS or
>> MEM_UOPS_RETIRED.ALL_LOADS
>> event if any of them is available.
>> Look up the /proc/iomem and resolve the physical address.
>> Provide memory type summary.
>>
>> Here is an example output.
>>  #perf script report mem-phys-addr
>> Event: mem_inst_retired.all_loads:P
>> Memory type                                    count   percentage
>> ----------------------------------------  -----------  -----------
>> System RAM                                        74        53.2%
>> Persistent Memory                                 55        39.6%
>> N/A                                               10         7.2%
>>
>> Signed-off-by: Kan Liang <Kan.liang@xxxxxxxxx>
>> ---
>>
>> Changes since V1:
>>  - Do not mix DLA and Load Latency. Do not compare the loads and stores.
>>    Only profile the loads.
>>  - Use event name to replace the RAW event
>>
>>  tools/perf/scripts/python/bin/mem-phys-addr-record | 19 +++++
>>  tools/perf/scripts/python/bin/mem-phys-addr-report |  3 +
>>  tools/perf/scripts/python/mem-phys-addr.py         | 97
>> ++++++++++++++++++++++
>>  .../util/scripting-engines/trace-event-python.c    |  2 +
>>  4 files changed, 121 insertions(+)
>>  create mode 100644 tools/perf/scripts/python/bin/mem-phys-addr-record
>>  create mode 100644 tools/perf/scripts/python/bin/mem-phys-addr-report
>>  create mode 100644 tools/perf/scripts/python/mem-phys-addr.py
>>
>> diff --git a/tools/perf/scripts/python/bin/mem-phys-addr-record
>> b/tools/perf/scripts/python/bin/mem-phys-addr-record
>> new file mode 100644
>> index 0000000..5a87512
>> --- /dev/null
>> +++ b/tools/perf/scripts/python/bin/mem-phys-addr-record
>> @@ -0,0 +1,19 @@
>> +#!/bin/bash
>> +
>> +#
>> +# Profiling physical memory by all retired load instructions/uops event
>> +# MEM_INST_RETIRED.ALL_LOADS or MEM_UOPS_RETIRED.ALL_LOADS
>> +#
>> +
>> +load=`perf list | grep mem_inst_retired.all_loads`
>> +if [ -z "$load" ]; then
>> +     load=`perf list | grep mem_uops_retired.all_loads`
>> +fi
>> +if [ -z "$load" ]; then
>> +     echo "There is no event to count all retired load instructions/uops."
>> +     exit 1
>> +fi
>> +
>> +arg=$(echo $load | tr -d ' ')
>> +arg="$arg:P"
>> +perf record --phys-data -e $arg $@
>> diff --git a/tools/perf/scripts/python/bin/mem-phys-addr-report
>> b/tools/perf/scripts/python/bin/mem-phys-addr-report
>> new file mode 100644
>> index 0000000..3f2b847
>> --- /dev/null
>> +++ b/tools/perf/scripts/python/bin/mem-phys-addr-report
>> @@ -0,0 +1,3 @@
>> +#!/bin/bash
>> +# description: resolve physical address samples
>> +perf script $@ -s "$PERF_EXEC_PATH"/scripts/python/mem-phys-addr.py
>> diff --git a/tools/perf/scripts/python/mem-phys-addr.py
>> b/tools/perf/scripts/python/mem-phys-addr.py
>> new file mode 100644
>> index 0000000..1d1f757
>> --- /dev/null
>> +++ b/tools/perf/scripts/python/mem-phys-addr.py
>> @@ -0,0 +1,97 @@
>> +# mem-phys-addr.py: Resolve physical address samples
>> +# Copyright (c) 2017, Intel Corporation.
>> +#
>> +# This program is free software; you can redistribute it and/or modify it
>> +# under the terms and conditions of the GNU General Public License,
>> +# version 2, as published by the Free Software Foundation.
>> +#
>> +# This program is distributed in the hope it will be useful, but WITHOUT
>> +# ANY WARRANTY; without even the implied warranty of
>> MERCHANTABILITY or
>> +# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
>> for
>> +# more details.

May be you could consider using an SPDX tag instead of this fine but
long legalese?
See Thomas doc patches [1] for details

[1] https://lkml.org/lkml/2017/12/28/323

>> +
>> +from __future__ import division
>> +import os
>> +import sys
>> +import struct
>> +import re
>> +import bisect
>> +import collections
>> +
>> +sys.path.append(os.environ['PERF_EXEC_PATH'] + \
>> +     '/scripts/python/Perf-Trace-Util/lib/Perf/Trace')
>> +
>> +system_ram = []
>> +pmem = []
>> +f = None
>> +load_mem_type_cnt = collections.Counter()
>> +event_name = None

nit. may be it does not matter too much.... but using globals
throughout as opposed to return values makes the script harder to read
IMHO.

>> +
>> +def parse_iomem():
>> +     global f
>> +     f = open('/proc/iomem', 'r')
>> +     for i, j in enumerate(f):
>> +             m = re.split('-|:',j,2)
>> +             if m[2].strip() == 'System RAM':
>> +                     system_ram.append(long(m[0], 16))
>> +                     system_ram.append(long(m[1], 16))
>> +             if m[2].strip() == 'Persistent Memory':
>> +                     pmem.append(long(m[0], 16))
>> +                     pmem.append(long(m[1], 16))
>> +
>> +def print_memory_type():
>> +     print "Event: %s" % (event_name)
>> +     print "%-40s  %10s  %10s\n" % ("Memory type", "count",
>> "percentage"),
>> +     print "%-40s  %10s  %10s\n" % ("----------------------------------------", \
>> +                                     "-----------", "-----------"),
>> +     total = sum(load_mem_type_cnt.values())
>> +     for mem_type, count in sorted(load_mem_type_cnt.most_common(),
>> \
>> +                                     key = lambda(k, v): (v, k), reverse =
>> True):
>> +             print "%-40s  %10d  %10.1f%%\n" % (mem_type, count, 100 *
>> count / total),
>> +
>> +def trace_begin():
>> +     parse_iomem()
>> +
>> +def trace_end():
>> +     print_memory_type()
>> +     f.close()
>> +
>> +def is_system_ram(phys_addr):
>> +     #/proc/iomem is sorted
>> +     position = bisect.bisect(system_ram, phys_addr)
>> +     if position % 2 == 0:
>> +             return False
>> +     return True
>> +
>> +def is_persistent_mem(phys_addr):
>> +     position = bisect.bisect(pmem, phys_addr)
>> +     if position % 2 == 0:
>> +             return False
>> +     return True
>> +
>> +def find_memory_type(phys_addr):
>> +     if phys_addr == 0:
>> +             return "N/A"
>> +     if is_system_ram(phys_addr):
>> +             return "System RAM"
>> +
>> +     if is_persistent_mem(phys_addr):
>> +             return "Persistent Memory"
>> +
>> +     #slow path, search all
>> +     f.seek(0, 0)
>> +     for j in f:
>> +             m = re.split('-|:',j,2)
>> +             if long(m[0], 16) <= phys_addr <= long(m[1], 16):
>> +                     return m[2]
>> +     return "N/A"
>> +
>> +def process_event(param_dict):
>> +     name       = param_dict["ev_name"]
>> +     sample     = param_dict["sample"]
>> +     phys_addr  = sample["phys_addr"]
>> +
>> +     global event_name
>> +     if event_name == None:
>> +             event_name = name
>> +     load_mem_type_cnt[find_memory_type(phys_addr)] += 1
>> diff --git a/tools/perf/util/scripting-engines/trace-event-python.c
>> b/tools/perf/util/scripting-engines/trace-event-python.c
>> index c7187f0..8cd6317 100644
>> --- a/tools/perf/util/scripting-engines/trace-event-python.c
>> +++ b/tools/perf/util/scripting-engines/trace-event-python.c
>> @@ -500,6 +500,8 @@ static PyObject *get_perf_sample_dict(struct
>> perf_sample *sample,
>>                       PyLong_FromUnsignedLongLong(sample->time));
>>       pydict_set_item_string_decref(dict_sample, "period",
>>                       PyLong_FromUnsignedLongLong(sample->period));
>> +     pydict_set_item_string_decref(dict_sample, "phys_addr",
>> +                     PyLong_FromUnsignedLongLong(sample-
>> >phys_addr));
>>       set_sample_read_in_dict(dict_sample, sample, evsel);
>>       pydict_set_item_string_decref(dict, "sample", dict_sample);
>>
>> --
>> 2.7.4
>


-- 
Cordially
Philippe Ombredanne