mirror of
https://github.com/genodelabs/genode.git
synced 2025-01-18 18:56:29 +00:00
8f9355b360
In the init configuration one can configure the donation of CPU time via 'resource' tags that have the attribute 'name' set to "CPU" and the attribute 'quantum' set to the percentage of CPU quota that init shall donate. The pattern is the same as when donating RAM quota. ! <start name="test"> ! <resource name="CPU" quantum="75"/> ! </start> This would cause init to try donating 75% of its CPU quota to the child "test". Init and core do not preserve CPU quota for their own requirements by default as it is done with RAM quota. The CPU quota that a process owns can be applied through the thread constructor. The constructor has been enhanced by an argument that indicates the percentage of the programs CPU quota that shall be granted to the new thread. So 'Thread(33, "test")' would cause the backing CPU session to try to grant 33% of the programs CPU quota to the thread "test". By now, the CPU quota of a thread can't be altered after construction. Constructing a thread with CPU quota 0 doesn't mean the thread gets never scheduled but that the thread has no guaranty to receive CPU time. Such threads have to live with excess CPU time. Threads that already existed in the official repositories of Genode were adapted in the way that they receive a quota of 0. This commit also provides a run test 'cpu_quota' in base-hw (the only kernel that applies the CPU-quota scheme currently). The test basically runs three threads with different physical CPU quota. The threads simply count for 30 seconds each and the test then checks wether the counter values relate to the CPU-quota distribution. fix #1275 |
||
|---|---|---|
| .. | ||
| doc | ||
| include | ||
| lib | ||
| ports | ||
| run | ||
| src | ||
| Makefile | ||
| README | ||
This directory contains ports of popular 3rd-party software to Genode. Usage ----- At the root of the 'libports' repository, there is 'Makefile' automating the task of downloading and preparing the library source codes. By just typing 'make', you get an overview of the available libraries and further instructions. In the common case, you might just want to prepare all packages by issuing: ! make prepare Alternatively, you can select individual packages to prepare by specifying their base names (without the version number) as command-line argument. For example, the following command prepares both the C library and the Freetype library: ! make prepare PKG="libc freetype" After having prepared the 'libports' repository, you are ready to include the repository into the build process by appending it to the 'REPOSITORIES' declaration of your '<build-dir>/etc/build.conf' file. Under the hood -------------- For each library, there is a file contained in the 'libports/ports/' subdirectory. The file is named after the library and contains the library-specific rules for downloading the source code and installing header files. How does 'libports' relate to the other repositories? ----------------------------------------------------- Most libraries hosted in the 'libports' repository expect a complete C library, which is provided with the 'libc' package. Please do not forget to prepare the libc package when using any of the other libports packages. The libc, in turn, depends on the 'os' repository for its back end. Because the 'os' repository is the home of the dynamic linker, libraries contained in 'libports' are safe to assume the presence of the dynamic linker and, thus, should be built as shared libraries.