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Diffstat (limited to 'Documentation/admin-guide/perf/hisi-pmu.rst')
| -rw-r--r-- | Documentation/admin-guide/perf/hisi-pmu.rst | 62 |
1 files changed, 57 insertions, 5 deletions
diff --git a/Documentation/admin-guide/perf/hisi-pmu.rst b/Documentation/admin-guide/perf/hisi-pmu.rst index 5cc248d18c63..d56b2d690709 100644 --- a/Documentation/admin-guide/perf/hisi-pmu.rst +++ b/Documentation/admin-guide/perf/hisi-pmu.rst @@ -18,9 +18,10 @@ HiSilicon SoC uncore PMU driver Each device PMU has separate registers for event counting, control and interrupt, and the PMU driver shall register perf PMU drivers like L3C, HHA and DDRC etc. The available events and configuration options shall -be described in the sysfs, see: +be described in the sysfs, see:: + +/sys/bus/event_source/devices/hisi_sccl{X}_<l3c{Y}/hha{Y}/ddrc{Y}> -/sys/bus/event_source/devices/hisi_sccl{X}_<l3c{Y}/hha{Y}/ddrc{Y}>. The "perf list" command shall list the available events from sysfs. Each L3C, HHA and DDRC is registered as a separate PMU with perf. The PMU @@ -35,7 +36,10 @@ e.g. hisi_sccl1_hha0/rx_operations is RX_OPERATIONS event of HHA index #0 in SCCL ID #1. The driver also provides a "cpumask" sysfs attribute, which shows the CPU core -ID used to count the uncore PMU event. +ID used to count the uncore PMU event. An "associated_cpus" sysfs attribute is +also provided to show the CPUs associated with this PMU. The "cpumask" indicates +the CPUs to open the events, usually as a hint for userspaces tools like perf. +It only contains one associated CPU from the "associated_cpus". Example usage of perf:: @@ -62,6 +66,10 @@ specified as a bitmap:: This will only count the operations from core/thread 0 and 1 in this cluster. +User should not use tt_core_deprecated to specify the core/thread filtering. +This option is provided for backward compatiblility and only support 8bit +which may not cover all the core/thread sharing L3C. + 2. Tracetag allow the user to chose to count only read, write or atomic operations via the tt_req parameeter in perf. The default value counts all operations. tt_req is 3bits, 3'b100 represents read operations, 3'b101 @@ -106,8 +114,52 @@ uring channel. It is 2 bits. Some important codes are as follows: - 2'b11: count the events which sent to the uring_ext (MATA) channel; - 2'b01: is the same as 2'b11; - 2'b10: count the events which sent to the uring (non-MATA) channel; -- 2'b00: default value, count the events which sent to the both uring and - uring_ext channel; +- 2'b00: default value, count the events which sent to both uring and + uring_ext channels; + +6. ch: NoC PMU supports filtering the event counts of certain transaction +channel with this option. The current supported channels are as follows: + +- 3'b010: Request channel +- 3'b100: Snoop channel +- 3'b110: Response channel +- 3'b111: Data channel + +7. tt_en: NoC PMU supports counting only transactions that have tracetag set +if this option is set. See the 2nd list for more information about tracetag. + +For HiSilicon uncore PMU v3 whose identifier is 0x40, some uncore PMUs are +further divided into parts for finer granularity of tracing, each part has its +own dedicated PMU, and all such PMUs together cover the monitoring job of events +on particular uncore device. Such PMUs are described in sysfs with name format +slightly changed:: + +/sys/bus/event_source/devices/hisi_sccl{X}_<l3c{Y}_{Z}/ddrc{Y}_{Z}/noc{Y}_{Z}> + +Z is the sub-id, indicating different PMUs for part of hardware device. + +Usage of most PMUs with different sub-ids are identical. Specially, L3C PMU +provides ``ext`` option to allow exploration of even finer granual statistics +of L3C PMU. L3C PMU driver uses that as hint of termination when delivering +perf command to hardware: + +- ext=0: Default, could be used with event names. +- ext=1 and ext=2: Must be used with event codes, event names are not supported. + +An example of perf command could be:: + + $# perf stat -a -e hisi_sccl0_l3c1_0/rd_spipe/ sleep 5 + +or:: + + $# perf stat -a -e hisi_sccl0_l3c1_0/event=0x1,ext=1/ sleep 5 + +As above, ``hisi_sccl0_l3c1_0`` locates PMU of Super CPU CLuster 0, L3 cache 1 +pipe0. + +First command locates the first part of L3C since ``ext=0`` is implied by +default. Second command issues the counting on another part of L3C with the +event ``0x1``. Users could configure IDs to count data come from specific CCL/ICL, by setting srcid_cmd & srcid_msk, and data desitined for specific CCL/ICL by setting |