Linux kernel modifications for the Kernel Hacking exam
2c4885d24e
While this is done for all bitmaps, the original use case in mind was for CPU masks and cpulist_parse() as described below. It seems that a common configuration is to use the 1st couple cores for housekeeping tasks. This tends to leave the remaining ones to form a pool of similarly configured cores to take on the real workload of interest to the user. So on machine A - with 32 cores, it could be 0-3 for "system" and then 4-31 being used in boot args like nohz_full=, or rcu_nocbs= as part of setting up the worker pool of CPUs. But then newer machine B is added, and it has 48 cores, and so while the 0-3 part remains unchanged, the pool setup cpu list becomes 4-47. Multiple deployment becomes easier when we can just simply replace 31 and 47 with "N" and let the system substitute in the actual number at boot; a number that it knows better than we do. Cc: Yury Norov <yury.norov@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Suggested-by: Yury Norov <yury.norov@gmail.com> # move it from CPU code Acked-by: Yury Norov <yury.norov@gmail.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
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.