context functions. We don't need to enter the kernel anymore. The
contexts are compatible (ie a context created by getcontext() can
be restored by _ia64_restore_context()).
While here, make the use of THR_ALIGNBYTES and THR_ALIGN a no-op.
They are going to be removed anyway.
We write 1 for r8 in the context so that _ia64_restore_context()
will return with a non-zero value. _ia64_save_context() always
return 0.
o In _ia64_restore_context(), don't restore the thread pointer. It
is not normally part of the context. Also, restore the return
registers. We get called for contexts created by getcontext(),
which means we have to restore all the syscall return values.
the userland version of [gs]etcontext to switch between a thread
and the UTS scheduler (and back again). This also fixes a bug
in i386 _thr_setcontext() which wasn't properly restoring the
context.
Reviewed by: davidxu
functions are derived from the swapctx() and restorectx() (resp)
from sys/ia64/ia64/context.s. The code is expected to be 99%
correct, but has not yet been tested.
Note that with these functions operating on mcontext_t, we also
created the foundation upon which we can implement getcontext(2)
and setcontext(2) replacements. It's not guaranteed that the use
of these syscalls and _ia64_{save|restore}_context() on the same
uicontext_t is actually going to work. Replacing the syscalls is
now trivially achieved.
This commit completes the ia64 port of libpthread itself (modulo
testing and bugfixes).
the register stack and memory stack and call the function given to it.
While here, provide empty, non-working, stubs for the context functions
(_ia64_save_context() and _ia64_restore_context()) so that anyone can at
least compile libkse from CVS sources. Real implementations will follow
soon.
minimize the amount and complexity of assembly code that needs to be
written. This way the core functionality is spread over 3 elementary
functions that don't have to do anything that can more easily and
more safely be done in C. As such, assembly code will only have to
know about the definition of mcontext_t.
The runtime cost of not having these functions being inlined is less
important than the cleanliness and maintainability of the code at
this stage of the implementation.
by moving the definition of struct ksd to pthread_md.h and removing
the inclusion of ksd.h from thr_private.h (which has the definition
of struct kse and kse_critical_t). This allows ksd.h to have inline
functions that use struct kse and kse_critical_t and generally
yields a cleaner implementation at the cost of not having all ksd
related types/definitions in one header.
Implement the ksd functionality on ia64 by using inline functions
and permanently remove ksd.c from the ia64 specific makefile.
This change does not clean up the i386 specific version of ksd.h.
NOTE: The ksd code on ia64 abuses the tp register in the same way
as it is abused in libthr in that it is incompatible with the
runtime specification. This will be address when support for TLS
hits the tree.
_ksd_readandclear_tmbx to be function-like. That way we
can define them as inline functions or create prototypes
for them.
This change allows the ksd interface on ia64 to be fully
inlined.
be external (initialize()!).
Remove cancellation points from _pthread_cond_wait and
_pthread_cond_timedwait (single underscore versions are
libc private functions). Point the weak reference(!) for
these functions to the versions with cancellation points.
Approved by: re@(blanket till 5/19)
Pointed out by: kan (cancellation point bug)
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.
In _thread_switch, set current thread pointer in kse mailbox
only after all registers copied out of thread mailbox, kernel will do
upcall at trap time, if set current thread pointer before loading all
registers from thread mailbox, at trap time, the thread mailbox data
will be overwritten by kernel, result is junk data is loaded into CPU.
completeness and doesn't get us a working libc_r there because libc_r
uses setjmp() and setjmp() cannot be used for context switches on ia64
as-is (or sparc64). Rather than making setjmp/longjmp behave like
the *context() calls, it would be far better to make libc_r use *context()
directly which is what they are for.
Obtained from: marcel