[PATCH v9 0/2] drivers/perf: hisi: Add support for PCIe PMU

From: Qi Liu
Date: Wed Aug 18 2021 - 04:36:51 EST

This patchset adds support for HiSilicon PCIe Performance Monitoring
Unit(PMU). It is a PCIe Root Complex integrated End Point(RCiEP) device
added on Hip09. Each PCIe Core has a PMU RCiEP to monitor multi root
ports and all Endpoints downstream these root ports.

HiSilicon PCIe PMU is supported to collect performance data of PCIe bus,
such as: bandwidth, latency etc.

Example usage of counting PCIe rx memory write latency::

$# perf stat -e hisi_pcie0_core0/rx_mwr_latency/
$# perf stat -e hisi_pcie0_core0/rx_mwr_cnt/
$# perf stat -g -e hisi_pcie0_core0/rx_mwr_latency/ -e hisi_pcie0_core0/rx_mwr_cnt/

average rx memory write latency can be calculated like this:
latency = rx_mwr_latency / rx_mwr_cnt.

Common PMU events and metrics will be described in JSON file, and will be add
in userspace perf tool latter.

Changes since v8:
- Remove subevent parameter in attr->config.
- Check the counter scheduling constraints when accepting an event group.
- Link: https://lore.kernel.org/linux-arm-kernel/20210728080932.72515-1-liuqi115@xxxxxxxxxx/

Changes since v7:
- Drop headerfile cpumask.h and cpuhotplug.h.
- Rename events in perf list: bw->flux, lat->delay, as driver doesn't
process bandwidth and average latency data.
- Link: https://lore.kernel.org/linux-arm-kernel/1624532384-43002-1-git-send-email-liuqi115@xxxxxxxxxx/

Changes since v6:
- Move the driver to drivers/perf/hisilicon.
- Treat content in PMU counter and ext_counter as different PMU events, and
export them separately.
- Address the comments from Will and Krzysztof.
- Link: https://lore.kernel.org/linux-arm-kernel/1622467951-32114-1-git-send-email-liuqi115@xxxxxxxxxx/

Changes since v5:
- Fix some errors when build under ARCH=xtensa.
- Link: https://lore.kernel.org/linux-arm-kernel/1621946795-14046-1-git-send-email-liuqi115@xxxxxxxxxx/

Changes since v4:
- Replace irq_set_affinity_hint() with irq_set_affinity().
- Link: https://lore.kernel.org/linux-arm-kernel/1621417741-5229-1-git-send-email-liuqi115@xxxxxxxxxx/

Changes since v3:
- Fix some warnings when build under 32bits architecture.
- Address the comments from John.
- Link: https://lore.kernel.org/linux-arm-kernel/1618490885-44612-1-git-send-email-liuqi115@xxxxxxxxxx/

Changes since v2:
- Address the comments from John.
- Link: https://lore.kernel.org/linux-arm-kernel/1617959157-22956-1-git-send-email-liuqi115@xxxxxxxxxx/

Changes since v1:
- Drop the internal Reviewed-by tag.
- Fix some build warnings when W=1.
- Link: https://lore.kernel.org/linux-arm-kernel/1617788943-52722-1-git-send-email-liuqi115@xxxxxxxxxx/

Qi Liu (2):
docs: perf: Add description for HiSilicon PCIe PMU driver
drivers/perf: hisi: Add driver for HiSilicon PCIe PMU

.../admin-guide/perf/hisi-pcie-pmu.rst | 106 ++
Documentation/admin-guide/perf/index.rst | 1 +
drivers/perf/hisilicon/Kconfig | 9 +
drivers/perf/hisilicon/Makefile | 2 +
drivers/perf/hisilicon/hisi_pcie_pmu.c | 972 ++++++++++++++++++
include/linux/cpuhotplug.h | 1 +
7 files changed, 1093 insertions(+)
create mode 100644 Documentation/admin-guide/perf/hisi-pcie-pmu.rst
create mode 100644 drivers/perf/hisilicon/hisi_pcie_pmu.c