63e39aa6ae
The TMA method level 2 metrics is supported from the Intel Sapphire
Rapids server, which expose four L2 Topdown metrics events to user
space. There are eight L2 events in total. The other four L2 Topdown
metrics events are calculated from the corresponding L1 and the exposed
L2 events.
Now, the --topdown prints the complete top-down metrics that supported
by the CPU. For the Intel Sapphire Rapids server, there are 4 L1 events
and 8 L2 events displyed in one line.
Add a new option, --td-level, to display the top-down statistics that
equal to or lower than the input level.
The L2 event is marked only when both its L1 parent event and itself
crosse the threshold.
Here is an example:
$ perf stat --topdown --td-level=2 --no-metric-only sleep 1
Topdown accuracy may decrease when measuring long periods.
Please print the result regularly, e.g. -I1000
Performance counter stats for 'sleep 1':
16,734,390 slots
2,100,001 topdown-retiring # 12.6% retiring
2,034,376 topdown-bad-spec # 12.3% bad speculation
4,003,128 topdown-fe-bound # 24.1% frontend bound
328,125 topdown-heavy-ops # 2.0% heavy operations # 10.6% light operations
1,968,751 topdown-br-mispredict # 11.9% branch mispredict # 0.4% machine clears
2,953,127 topdown-fetch-lat # 17.8% fetch latency # 6.3% fetch bandwidth
5,906,255 topdown-mem-bound # 35.6% memory bound # 15.4% core bound
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/1612296553-21962-9-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.