Re: [PATCH V8 22/23] perf tools: making coresight PMU listable

[Adrian Hunter <adrian.hunter@intel.com>]

On 25/01/16 23:10, Arnaldo Carvalho de Melo wrote:
> Em Mon, Jan 25, 2016 at 01:49:47PM -0700, Mathieu Poirier escreveu:
>> On 14 January 2016 at 14:46, Mathieu Poirier <mathieu.poirier@linaro.org> wrote:
>>> Adding the required mechanic allowing 'perf list pmu' to
>>> discover coresight ETM/PTM tracers.
>>>
>>> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
>>> Cc: Ingo Molnar <mingo@redhat.com>
>>> Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
>>> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
>>> ---
>>>  MAINTAINERS                    |  1 +
>>>  tools/perf/arch/arm/util/Build |  2 ++
>>>  tools/perf/arch/arm/util/pmu.c | 34 ++++++++++++++++++++++++++++++++++
>>>  tools/perf/config/Makefile     | 17 ++++++++++++-----
>>>  4 files changed, 49 insertions(+), 5 deletions(-)
>>>  create mode 100644 tools/perf/arch/arm/util/pmu.c
>>>
>>> diff --git a/MAINTAINERS b/MAINTAINERS
>>> index 233f83464814..b2a92245eece 100644
>>> --- a/MAINTAINERS
>>> +++ b/MAINTAINERS
>>> @@ -1007,6 +1007,7 @@ F:        drivers/hwtracing/coresight/*
>>>  F:     Documentation/trace/coresight.txt
>>>  F:     Documentation/devicetree/bindings/arm/coresight.txt
>>>  F:     Documentation/ABI/testing/sysfs-bus-coresight-devices-*
>>> +F:     tools/perf/arch/arm/util/pmu.c
>>>
>>>  ARM/CORGI MACHINE SUPPORT
>>>  M:     Richard Purdie <rpurdie@rpsys.net>
>>> diff --git a/tools/perf/arch/arm/util/Build b/tools/perf/arch/arm/util/Build
>>> index d22e3d07de3d..66ab0b05549c 100644
>>> --- a/tools/perf/arch/arm/util/Build
>>> +++ b/tools/perf/arch/arm/util/Build
>>> @@ -2,3 +2,5 @@ libperf-$(CONFIG_DWARF) += dwarf-regs.o
>>>
>>>  libperf-$(CONFIG_LIBUNWIND)          += unwind-libunwind.o
>>>  libperf-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o
>>> +
>>> +libperf-$(CONFIG_AUXTRACE) += pmu.o
>>> diff --git a/tools/perf/arch/arm/util/pmu.c b/tools/perf/arch/arm/util/pmu.c
>>> new file mode 100644
>>> index 000000000000..af9fb666b44f
>>> --- /dev/null
>>> +++ b/tools/perf/arch/arm/util/pmu.c
>>> @@ -0,0 +1,34 @@
>>> +/*
>>> + * Copyright(C) 2015 Linaro Limited. All rights reserved.
>>> + * Author: Mathieu Poirier <mathieu.poirier@linaro.org>
>>> + *
>>> + * This program is free software; you can redistribute it and/or modify it
>>> + * under the terms of the GNU General Public License version 2 as published by
>>> + * the Free Software Foundation.
>>> + *
>>> + * This program is distributed in the hope that 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.
>>> + *
>>> + * You should have received a copy of the GNU General Public License along with
>>> + * this program.  If not, see <http://www.gnu.org/licenses/>.
>>> + */
>>> +
>>> +#include <string.h>
>>> +#include <linux/coresight-pmu.h>

Probably need to add include/linux/coresight-pmu.h it to tools/perf/MANIFEST

>>> +#include <linux/perf_event.h>
>>> +
>>> +#include "../../util/pmu.h"
>>> +
>>> +struct perf_event_attr
>>> +*perf_pmu__get_default_config(struct perf_pmu *pmu __maybe_unused)
>>> +{
>>> +#ifdef HAVE_AUXTRACE_SUPPORT
>>> +       if (!strcmp(pmu->name, CORESIGHT_ETM_PMU_NAME)) {
>>> +               /* add ETM default config here */
>>> +               pmu->selectable = true;
>>> +       }
>>> +#endif
>>> +       return NULL;
>>> +}
>>> diff --git a/tools/perf/config/Makefile b/tools/perf/config/Makefile
>>> index de89ec574361..905faabff8b1 100644
>>> --- a/tools/perf/config/Makefile
>>> +++ b/tools/perf/config/Makefile
>>> @@ -647,12 +647,19 @@ ifdef LIBBABELTRACE
>>>  endif
>>>
>>>  ifndef NO_AUXTRACE
>>> -  ifeq ($(feature-get_cpuid), 0)
>>> -    msg := $(warning Your gcc lacks the __get_cpuid() builtin, disables support for auxtrace/Intel PT, please install a newer gcc);
>>> -    NO_AUXTRACE := 1
>>> +  ifeq ($(ARCH),x86)
>>> +    ifeq ($(feature-get_cpuid), 0)
>>> +      msg := $(warning Your gcc lacks the __get_cpuid() builtin, disables support for auxtrace/Intel PT, please install a newer gcc);
>>> +      NO_AUXTRACE := 1
>>> +    else
>>> +      $(call detected,CONFIG_AUXTRACE)
>>> +      CFLAGS += -DHAVE_AUXTRACE_SUPPORT
>>> +    endif
>>>    else
>>> -    $(call detected,CONFIG_AUXTRACE)
>>> -    CFLAGS += -DHAVE_AUXTRACE_SUPPORT
>>> +    ifeq ($(ARCH),$(filter $(ARCH), arm arm64))
>>> +      $(call detected,CONFIG_AUXTRACE)
>>> +      CFLAGS += -DHAVE_AUXTRACE_SUPPORT
>>> +    endif

We still want AUXTRACE support by default, to support being able to decode a
trace from one machine on any other machine, so this should not exclude
HAVE_AUXTRACE_SUPPORT from every arch except x86 and arm.

>>>    endif
>>>  endif
>>>
>>> --
>>> 2.1.4
>>>
>>
>> Arnaldo,
>>
>> This is the third (of four) patch that I can't queue without a
>> reviewed by from you.
>>
>> It has been rebased to 4.5-rc1 here [1] for your convenience.  I will
>> be happy to use another baseline should that be more adequate for you.
> 
> Adrian,
> 
> 	Are you ok with this?

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