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42a5864cf0
The multiplexing scaling in perf stat mysteriously adds 0.5 to the
value. This dates back to the original perf tool. Other scaling code
doesn't use that strange convention. Remove the extra 0.5.
Before:
$ perf stat -e 'cycles,cycles,cycles,cycles,cycles,cycles' grep -rq foo
Performance counter stats for 'grep -rq foo':
6,403,580 cycles (81.62%)
6,404,341 cycles (81.64%)
6,402,983 cycles (81.62%)
6,399,941 cycles (81.63%)
6,399,451 cycles (81.62%)
6,436,105 cycles (91.87%)
0.005843799 seconds time elapsed
0.002905000 seconds user
0.002902000 seconds sys
After:
$ perf stat -e 'cycles,cycles,cycles,cycles,cycles,cycles' grep -rq foo
Performance counter stats for 'grep -rq foo':
6,422,704 cycles (81.68%)
6,401,842 cycles (81.68%)
6,398,432 cycles (81.68%)
6,397,098 cycles (81.68%)
6,396,074 cycles (81.67%)
6,434,980 cycles (91.62%)
0.005884437 seconds time elapsed
0.003580000 seconds user
0.002356000 seconds sys
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
LPU-Reference: 20190314225002.30108-10-andi@firstfloor.org
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.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.