technique) so that we don't wind up calling into an application's
version if the application defines them.
Inspired by: qpopper's interfering and buggy version of strlcpy
a thread lock).
Better protect access to thread state while searching for
threads to handle a signal.
Better protect access to process pending signals while processing
a thread in sigwait().
Submitted by: davidxu
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.
While I'm here, use the TAILQ_FOREACH macro instead of a more
manual method which was inherited from libc_r (so we could
remove elements from the list which isn't needed for libpthread).
Submitted by: Kazuaki Oda <kaakun@highway.ne.jp>
setgrent, and endgrent also. (The previous NSS implementation used to
simply twiddle the internal data of the various modules directly.)
A symptom (group list set incorrectly in sshd) was
Reported by: Glenn Johnson <gjohnson@srrc.ars.usda.gov>
Sponsored by: DARPA, Network Associates Laboratories
idea to re-initialize `struct passwd', because e.g. pw_class might
get set by one module, but not by another. Add another call to the
internal pwd_init function to accomplish this.
Sponsored by: DARPA, Network Associates Laboratories
password must necessarily have an empty pwd->pw_passwd. Also add a check
that prevents users from setting a blank password unless the nullok option
was specified. Root is still allowed to give anyone a blank password.
Correct a bug that should have wreaked havoc everywhere, but for
some reason only bit unlucky people who use `-march' optimizations.
The compiler cannot assist one in distinguishing between the two
function calls below.
int nsdispatch(void *, ...);
void *discard;
nsdispatch(&discard, ...); /* correct .. no, really! */
nsdispatch(discard, ...); /* Boom */
Robin provided me with a debugging environment in which I could see
what was going on.
Badness when using CPUTYPE was
Reported by: "Robin P. Blanchard" <Robin.Blanchard@gactr.uga.edu>
Reported by: nork
Sponsored by: DARPA, Network Associates Laboratories
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
lock level is 0. Thus far, the threads implementation doesn't use
mutexes or condition variables so the lock level should be 0.
Save the return value when trying to schedule a new thread and
use this to return an error from pthread_create().
Change the max sleep time for an idle KSE to 1 minute from 2 minutes.
Maintain a count of the number of KSEs within a KSEG.
With these changes scope system threads seem to work, but heavy
use of them crash the kernel (supposedly VM bugs).
An incorrectly-sized allocation was being made due to an incorrect
argument to the `sizeof' operator. Obvious, because it violated the
`foo = malloc(sizeof(*foo))' idiom. Hard-to-see, because it was a
missing `*' (`*p' versus `**p').
Resulting failure was
Reported by: ache
Sponsored by: DARPA, Network Associates Laboratories
privileges. To do so may cause the NIS server to log spurious and
annoying `access denied' messages.
Reported by: Philip Paeps <philip@paeps.cx>
Sponsored by: DARPA, Network Associates Laboratories
to be instances where the kernel doesn't properly save and/or
restore it.
Use noupcall and nocompleted flags in the KSE mailbox. These
require kernel changes to work which will be committed sometime
later. Things still work without the changes.
Remove the general kse entry function and use two different
functions -- one for scope system threads and one for scope
process threads. The scope system function is not yet enabled
and we use the same function for all threads at the moment.
Keep a copy of the KSE stack for the case that a KSE runs
a scope system thread and uses the same stack as the thread
(no upcalls are generated, so a separate stack isn't needed).
This isn't enabled yet.
Use a separate field for the KSE waiting flag. It isn't
correct to use the mailbox flags field.
The following fixes were provided by David Xu:
o Initialize condition variable locks with thread versions
of the low-level locking functions instead of the kse versions.
o Enable threading before creating the first thread instead
of after.
o Don't enter critical regions when trying to malloc/free
or call functions that malloc/free.
o Take the scheduling lock when inheriting thread attributes.
o Check the attribute's stack pointer instead of the
attributes stack size for null when allocating a
thread's stack.
o Add a kseg reinit function so we don't have to destroy and
then recreate the same lock.
o Check the return value of kse_create() and return an
appropriate error if it fails.
o Don't forget to destroy a thread's locks when freeing it.
o Examine the correct flags word for checking to see if
a thread is in a synchronization queue.
Things should now work on an SMP kernel.
Note that the tp register (r13) is reserved as the TLS pointer in
the same way that that gp register (r1) is reserved as the global
pointer. This implementation uses the tp register to point to the
thread structure used by the threads implementation. This is not
in violation with the runtime specification provided the TLS is
a fixed distance from the thread structure. This is only an issue
when code used the __thread keyword to create TLS. This is not
supported at the moment.
in the mac.3 library man page. They were already cross-referenced
at the end of the man page, just not explicitly listed here.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
libthr. No changes were made to libpthread by request of deischen,
who will soon commit a real implementation for that library.
PR: standards/50848
Submitted by: Sergey A. Osokin <osa@freebsd.org.ru>
MFC after: 1 week
