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95149369c1
Most CPUs do not have a hardware c1 counter, and so turbostat derives c1 residency: c1 = TSC - MPERF - other_core_cstate_counters As it is not possible to atomically read these coutners, measurement jitter can case this calcuation to "go negative" when very close to 0. Turbostat detect that case and simply prints c1 = 0.00% But that check neglected to account for systems where the TSC crystal clock domain and the MPERF BCLK domain are differ by a small amount. That allowed very small negative c1 numbers to escape this check and be printed as huge positve numbers. This code begs for a bit of cleanup, but this patch is the minimal change to fix the issue. Signed-off-by: Len Brown <len.brown@intel.com>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. 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.