|author||Saleem Abdulrasool <firstname.lastname@example.org>||Wed Aug 02 10:12:39 2017 -0700|
|committer||Saleem Abdulrasool <email@example.com>||Thu Aug 03 20:54:54 2017 -0700|
linux: update header used for `major` macro Newer versions of glibc indicate that they intend to move the major macro from sys/types.h to sys/sysmacros.h. Add a check for the header and include that earlier to ensure that the macro is provided by the newer header when available/possible. This avoids an unnecessary warning from the system headers. Because `config_ac.h` is not available at the right location, we cannot include the header to check whether the header is available. Rely on the compiler provided `__has_include` instead of the configure check. Adjust the inclusion of `sys/cdefs.h` accordingly.
Grand Central Dispatch (GCD or libdispatch) provides comprehensive support for concurrent code execution on multicore hardware.
libdispatch is currently available on all Darwin platforms. This project aims to make a modern version of libdispatch available on all other Swift platforms. To do this, we will implement as much of the portable subset of the API as possible, using the existing open source C implementation.
libdispatch on Darwin is a combination of logic in the
xnu kernel alongside the user-space Library. The kernel has the most information available to balance workload across the entire system. As a first step, however, we believe it is useful to bring up the basic functionality of the library using user-space pthread primitives on Linux. Eventually, a Linux kernel module could be developed to support more informed thread scheduling.
A port of libdispatch to Linux has been completed. On Linux, since Swift 3, swift-corelibs-libdispatch has been included in all Swift releases and is used by other swift-corelibs projects.
Opportunities to contribute and on-going work include:
For detailed instructions on building and installing libdispatch, see INSTALL.md
For detailed instructions on testing libdispatch, see TESTING.md