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Commit0aa802a794("perf stat: Get rid of extra clock display function") introduced scale and unit for clock events. Thus, perf_stat__update_shadow_stats() now saves scaled values of clock events in msecs, instead of original nsecs. But while calculating values of shadow stats we still consider clock event values in nsecs. This results in a wrong shadow stat values. Ex, # ./perf stat -e task-clock,cycles ls <SNIP> 2.60 msec task-clock:u # 0.877 CPUs utilized 2,430,564 cycles:u # 1215282.000 GHz Fix this by saving original nsec values for clock events in perf_stat__update_shadow_stats(). After patch: # ./perf stat -e task-clock,cycles ls <SNIP> 3.14 msec task-clock:u # 0.839 CPUs utilized 3,094,528 cycles:u # 0.985 GHz Suggested-by: Jiri Olsa <jolsa@redhat.com> Reported-by: Anton Blanchard <anton@samba.org> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Reviewed-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jin Yao <yao.jin@linux.intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Thomas Richter <tmricht@linux.vnet.ibm.com> Cc: yuzhoujian@didichuxing.com Fixes:0aa802a794("perf stat: Get rid of extra clock display function") Link: http://lkml.kernel.org/r/20181116042843.24067-1-ravi.bangoria@linux.ibm.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.