6f765bbbfb
Currently the & and | operators are only used in metric thresholds like (from the tma_retiring metric): tma_retiring > 0.7 | tma_heavy_operations > 0.1 Thresholds are always computed when present, but a lack of events may mean the threshold can't be computed. This happens with the option --metric-no-threshold for say the metric tma_retiring on Tigerlake model CPUs. To fully compute the threshold tma_heavy_operations is needed and it needs the extra events of IDQ.MS_UOPS, UOPS_DECODED.DEC0, cpu/UOPS_DECODED.DEC0,cmask=1/ and IDQ.MITE_UOPS. So --metric-no-threshold is a useful option to reduce the number of events needed and potentially multiplexing of events. Rather than just fail threshold computations like this, we may know a result from just the left or right-hand side. So, for tma_retiring if its value is "> 0.7" we know it is over the threshold. This allows the metric to have the threshold coloring, when possible, without all the counters being programmed. Reviewed-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: Kan Liang <kan.liang@linux.intel.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ahmad Yasin <ahmad.yasin@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Caleb Biggers <caleb.biggers@intel.com> Cc: Eduard Zingerman <eddyz87@gmail.com> Cc: Edward Baker <edward.baker@intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Perry Taylor <perry.taylor@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Samantha Alt <samantha.alt@intel.com> Cc: Stephane Eranian <eranian@google.com> Cc: Weilin Wang <weilin.wang@intel.com> Link: https://lore.kernel.org/r/20230519063719.1029596-1-irogers@google.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.