The new implementation relieves the main entrypoint from monitor jobs
for contended lock primitives and is based on custom applicant data
structures, per-lock resp. per-semaphore applicant lists, and a
libc-internal blockade with timeouts based on libc kernel primitives.
The libc monitor facility enables the execution of monitor jobs by the
main thread when the monitor pool was charged. In comparison to the
current suspend/resume_all mechanism the main thread iterates over all
job functions in contrast to waking up all threads to check their
conditions by themselves. Threads are only woken up if the completion
condition was met.
This commit is the result of a collaboration with Christian Prochaska.
Many thanks for your support, Christian.
Fixes#3550
Defer destruction of threads which tries to self-destruct. Check an perform
cleanup of such threads during pthread_cancel and pthread_create.
Issue #1687
This patch changes the top-level directory layout as a preparatory
step for improving the tools for managing 3rd-party source codes.
The rationale is described in the issue referenced below.
Issue #1082
Christian Helmuth
Christian Prochaska
Norman Feske
Alexander Boettcher