Re: [PATCH v3 0/8] Add support for HiSilicon PCIe Tune and Trace device

[Yicong Yang <yangyicong@huawei.com>]

Hi perf, ETM and PCI related experts,

a gentle ping ... appreciate for the comments.

thanks.

On 2022/1/24 21:11, Yicong Yang wrote:
> HiSilicon PCIe tune and trace device (PTT) is a PCIe Root Complex
> integrated Endpoint (RCiEP) device, providing the capability
> to dynamically monitor and tune the PCIe traffic (tune),
> and trace the TLP headers (trace).
> 
> PTT tune is designed for monitoring and adjusting PCIe link parameters.
> We provide several parameters of the PCIe link. Through the driver,
> user can adjust the value of certain parameter to affect the PCIe link
> for the purpose of enhancing the performance in certian situation.
> 
> PTT trace is designed for dumping the TLP headers to the memory, which
> can be used to analyze the transactions and usage condition of the PCIe
> Link. Users can choose filters to trace headers, by either requester
> ID, or those downstream of a set of Root Ports on the same core of the
> PTT device. It's also supported to trace the headers of certain type and
> of certain direction.
> 
> The driver registers a PMU device for each PTT device. The trace can
> be used through `perf record` and the traced headers can be decoded
> by `perf report`. The perf command support for the device is also
> added in this patchset. The tune can be used through the sysfs
> attributes of related PMU device. See the documentation for the
> detailed usage.
> 
> Change since v2:
> - address the comments from Mathieu
>   - rename the directory to ptt to match the function of the device
>   - spinoff the declarations to a separate header
>   - split the trace function to several patches
>   - some other comments.
> - make default smmu domain type of PTT device to identity
>   Drop the RMR as it's not recommended and use an iommu_def_domain_type
>   quirk to passthrough the device DMA as suggested by Robin. 
> Link: https://lore.kernel.org/linux-pci/20211116090625.53702-1-yangyicong@hisilicon.com/
> 
> Change since v1:
> - switch the user interface of trace to perf from debugfs
> - switch the user interface of tune to sysfs from debugfs
> - add perf tool support to start trace and decode the trace data
> - address the comments of documentation from Bjorn
> - add RMR[1] support of the device as trace works in RMR mode or
>   direct DMA mode. RMR support is achieved by common APIs rather
>   than the APIs implemented in [1].
> Link: https://lore.kernel.org/lkml/1618654631-42454-1-git-send-email-yangyicong@hisilicon.com/
> 
> [1] https://lore.kernel.org/linux-acpi/20210805080724.480-1-shameerali.kolothum.thodi@huawei.com/
> 
> Qi Liu (1):
>   perf tool: Add support for HiSilicon PCIe Tune and Trace device driver
> 
> Yicong Yang (7):
>   hwtracing: Add trace function support for HiSilicon PCIe Tune and
>     Trace device
>   hisi_ptt: Register PMU device for PTT trace
>   hisi_ptt: Add support for dynamically updating the filter list
>   hisi_ptt: Add tune function support for HiSilicon PCIe Tune and Trace
>     device
>   docs: Add HiSilicon PTT device driver documentation
>   MAINTAINERS: Add maintainer for HiSilicon PTT driver
>   iommu/arm-smmu-v3: Make default domain type of HiSilicon PTT device to
>     identity
> 
>  Documentation/trace/hisi-ptt.rst              |  304 +++++
>  MAINTAINERS                                   |    7 +
>  drivers/Makefile                              |    1 +
>  drivers/hwtracing/Kconfig                     |    2 +
>  drivers/hwtracing/ptt/Kconfig                 |   11 +
>  drivers/hwtracing/ptt/Makefile                |    2 +
>  drivers/hwtracing/ptt/hisi_ptt.c              | 1124 +++++++++++++++++
>  drivers/hwtracing/ptt/hisi_ptt.h              |  239 ++++
>  drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c   |   16 +
>  tools/perf/arch/arm/util/auxtrace.c           |   56 +-
>  tools/perf/arch/arm/util/pmu.c                |    3 +
>  tools/perf/arch/arm64/util/Build              |    2 +-
>  tools/perf/arch/arm64/util/hisi_ptt.c         |  195 +++
>  tools/perf/util/Build                         |    2 +
>  tools/perf/util/auxtrace.c                    |    4 +
>  tools/perf/util/auxtrace.h                    |    1 +
>  tools/perf/util/hisi-ptt-decoder/Build        |    1 +
>  .../hisi-ptt-decoder/hisi-ptt-pkt-decoder.c   |  170 +++
>  .../hisi-ptt-decoder/hisi-ptt-pkt-decoder.h   |   28 +
>  tools/perf/util/hisi_ptt.c                    |  228 ++++
>  tools/perf/util/hisi_ptt.h                    |   28 +
>  21 files changed, 2420 insertions(+), 4 deletions(-)
>  create mode 100644 Documentation/trace/hisi-ptt.rst
>  create mode 100644 drivers/hwtracing/ptt/Kconfig
>  create mode 100644 drivers/hwtracing/ptt/Makefile
>  create mode 100644 drivers/hwtracing/ptt/hisi_ptt.c
>  create mode 100644 drivers/hwtracing/ptt/hisi_ptt.h
>  create mode 100644 tools/perf/arch/arm64/util/hisi_ptt.c
>  create mode 100644 tools/perf/util/hisi-ptt-decoder/Build
>  create mode 100644 tools/perf/util/hisi-ptt-decoder/hisi-ptt-pkt-decoder.c
>  create mode 100644 tools/perf/util/hisi-ptt-decoder/hisi-ptt-pkt-decoder.h
>  create mode 100644 tools/perf/util/hisi_ptt.c
>  create mode 100644 tools/perf/util/hisi_ptt.h
>