summaryrefslogtreecommitdiff
path: root/Documentation/admin-guide/perf
diff options
context:
space:
mode:
authorJing Zhang <renyu.zj@linux.alibaba.com>2023-07-28 15:09:35 +0800
committerArnaldo Carvalho de Melo <acme@redhat.com>2023-07-28 19:01:17 -0300
commitf849ce6baf467ea7fb9e68ae05d5d045f3aa89e8 (patch)
treec0e25e40473d0978ed028025b7963a9583932d74 /Documentation/admin-guide/perf
parent3e65bd13746af54bbe9a9c415a437bcc0b78282c (diff)
perf docs: Update metric usage for Alibaba's T-Head PMU driver (arm64)
Alibaba's T-Head ali_drw PMU supports DDR bandwidth metrics. Update its usage in the documentation. Reviewed-by: John Garry <john.g.garry@oracle.com> Signed-off-by: Jing Zhang <renyu.zj@linux.alibaba.com> Acked-by: Ian Rogers <irogers@google.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Shuai Xue <xueshuai@linux.alibaba.com> Cc: Will Deacon <will@kernel.org> Cc: Zhuo Song <zhuo.song@linux.alibaba.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-doc@vger.kernel.org Link: https://lore.kernel.org/r/1690528175-2499-4-git-send-email-renyu.zj@linux.alibaba.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'Documentation/admin-guide/perf')
-rw-r--r--Documentation/admin-guide/perf/alibaba_pmu.rst5
1 files changed, 5 insertions, 0 deletions
diff --git a/Documentation/admin-guide/perf/alibaba_pmu.rst b/Documentation/admin-guide/perf/alibaba_pmu.rst
index 11de998bb480..7d840023903f 100644
--- a/Documentation/admin-guide/perf/alibaba_pmu.rst
+++ b/Documentation/admin-guide/perf/alibaba_pmu.rst
@@ -88,6 +88,11 @@ data bandwidth::
-e ali_drw_27080/hif_rmw/ \
-e ali_drw_27080/cycle/ -- sleep 10
+Example usage of counting all memory read/write bandwidth by metric::
+
+ perf stat -M ddr_read_bandwidth.all -- sleep 10
+ perf stat -M ddr_write_bandwidth.all -- sleep 10
+
The average DRAM bandwidth can be calculated as follows:
- Read Bandwidth = perf_hif_rd * DDRC_WIDTH * DDRC_Freq / DDRC_Cycle