signals instead of having more intricate knowledge of thread state
within signal handling.
Simplify signal code because of above (by David Xu).
Use macros for libpthread usage of pthread_cleanup_push() and
pthread_cleanup_pop(). This removes some instances of malloc()
and free() from the semaphore and pthread_once() implementations.
When single threaded and forking(), make sure that the current
thread's signal mask is inherited by the forked thread.
Use private mutexes for libc and libpthread. Signals are
deferred while threads hold private mutexes. This fix also
breaks www/linuxpluginwrapper; a patch that fixes it is at
http://people.freebsd.org/~deischen/kse/linuxpluginwrapper.diff
Fix race condition in condition variables where handling a
signal (pthread_kill() or kill()) may not see a wakeup
(pthread_cond_signal() or pthread_cond_broadcast()).
In collaboration with: davidxu
archs that can (or are required to) have per-thread registers.
Tested on i386, amd64; marcel is testing on ia64 and will
have some follow-up commits.
Reviewed by: davidxu
is system bound thread and when it is blocked, no upcall is generated.
o Add ability to libkse to allow it run in pure 1:1 threading mode,
defining SYSTEM_SCOPE_ONLY in Makefile can turn on this option.
o Eliminate code for installing dummy signal handler for sigwait call.
o Add hash table to find thread.
Reviewed by: deischen
a lock is being waitied on.
Fix a races in join and cancellation.
When trying to wait on a CV and the library is not yet
threaded, make it threaded so that waiting actually works.
When trying to nanosleep() and we're not threaded, just
call the system call nanosleep instead of adding the thread
to the wait queue.
Clean up adding/removing new threads to the "all threads queue",
assigning them unique ids, and tracking how many active threads
there are. Do it all when the thread is added to the scheduling
queue instead of making pthread_create() know how to do it.
Fix a race where a thread could be marked for signal delivery
but it could be exited before we actually add the signal to it.
Other minor cleanups and bug fixes.
Submitted by: davidxu
Approved by: re@ (blanket for libpthread)
KSEs when it's thread exits; allow the GC handler to do that.
o Make spinlock/spinlock critical regions.
The following were submitted by davidxu
o Alow thr_switch() to take a null mailbox argument.
o Better protect cancellation checks.
o Don't set KSE specific data when creating new KSEs; rely on the
first upcall of the KSE to set it.
o Add the ability to set the maximum concurrency level and do this
automatically. We should have a way to enable/disable this with
some sort of tunable because some applications may not want this
to be the default.
o Hold the scheduling lock across thread switch calls.
o If scheduling of a thread fails, make sure to remove it from the list
of active threads.
o Better protect accesses to a joining threads when the target thread is
exited and detached.
o Remove some macro definitions that are now provided by <sys/kse.h>.
o Don't leave the library in threaded mode if creation of the initial
KSE fails.
o Wakeup idle KSEs when there are threads ready to run.
o Maintain the number of threads active in the priority queue.
provided by Sergey A. Osokin <osa@freebsd.org.ru>.
In order to test this on a single CPU machine, you need to:
sysctl kern.threads.debug=1
sysctl kern.threads.virtual_cpu=2
