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The CC1 column in tubostat can be computed by subtracting the core c-state residency countes from the total Cx residency. CC1 = (Idle_time_as_measured by MPERF) - (all core C-states with residency counters) However, as the underlying counter reads are not atomic, error can be noticed in this calculations, especially when the numbers are small. Denverton has a hardware CC1 residency counter to improve the accuracy of the cc1 statistic -- use it. At the same time, Denverton has no concept of CC3, PC3, CC7, PC7, so skip collecting and printing those columns. Finally, a note of clarification. Turbostat prints the standard PC2 residency counter, but on Denverton hardware, that actually means PC1E. Turbostat prints the standard PC6 residency counter, but on Denverton hardware, that actually means PC2. At this point, we document that differnce in this commit message, rather than adding a quirk to the software. 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.