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

From: Liang, Kan
Date: Thu Jan 04 2018 - 10:19:52 EST



> 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
>

Thanks Philippe.
I will update the license in V3.


> >> +
> >> +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.
>

The python script is embedded into C code. It implements the standard
interfaces. I think the globals should be a good way to share between
functions and among each calls. Otherwise, it has to change the interfaces,
which will impact other existing scripts.

Thanks,
Kan

> >> +
> >> +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