default syscall asm, so add it to NOASM. The other syscalls that manipulate
kernel threads use the default asm code, so they just get built
automatically.
file works with libpthread, but when built into libc_r which has a non-weak
symbol of the same name, the linker behaves unpredicatably and sometimes
links the wrong symbol. The linker behaviour is a byproduct of what
the program calls from object to object so it is like winning a lottery
if the program actually works. The odds are quite good - 95:1, I think.
We need a sure thing, though, so weak symbols can't be used instead
of renaming things.
of the one in libc that contains the weak symbol for __error. FreeBSD's
make accumulates paths to the point that it can find *anything*, possibly
including the car keys.
for the process, not a separate set for each thread). By default, the
process now only has signal handlers installed for SIGVTALRM, SIGINFO
and SIGCHLD. The thread kernel signal handler is installed for other
signals on demand. This means that SIG_IGN and SIG_DFL processing is now
left to the kernel, not the thread kernel.
Change the signal dispatch to no longer use a signal thread, and
call the signal handler using the stack of the thread that has the
signal pending.
Change the atomic lock method to use test-and-set asm code with
a yield if blocked. This introduces separate locks for each type
of object instead of blocking signals to prevent a context
switch. It was this blocking of signals that caused the performance
degradation the people have noted.
This is a *big* change!
Note odd `sigmask()' line in synopsis. `sigsetops(3)' is better suited
for `sigprocmask' and is already referenced from the manual page.
(`sigmask()' is useful for the older (& deprecated) `sigsetmask()' API).
PR: 6395
Reviewed by: phk
Submitted by: Joseph Koshy <koshy@india.hp.com>
leading XXX's. It could wrap an uppercase character through chars
like: [ \ ] ^ _ ` in between Z and a. The backslash and back tick
might be particularly nasty in a shell script context. Also, since
we've been using upper-case generated values for a while now, go with
the flow and use them in the pathname search rotation.
it was. Add a FILE_WAIT state and queue threads waiting for a FILE
lock. Start using the sys/queue.h macros instead of the way that MIT
pthreads did it.
Add a thread name to the private thread structure and a non-POSIX
function to set this. This helps (me at least) when sending a SIGINFO
to a threaded process to get a /tmp/uthread.dump to see what the
<expletive deleted> threads are doing this time. It is nice to be
able to recognise (yes, I spell that with an 's' too) which threads
are which.
Change the FILE locking to support kernel threads when linked with
libpthread (which you haven't see yet). This requires that libc become
thread-safe and thread-aware, testing __isthreaded before attempting
to do lock/unlock calls. The impact on non-threaded programs is minor.
This change works with libc_r, so it's the best compromise.
libc to determine if locking is required. This is needed in libc
for use with kernel threads, but until a thread is created, we don't
really want to bother locking things. The variable was added here
because the crt code calls exit(main()) so all programs will get the
variable.
