src/lib/libc_r/uthread/uthread_spec.c, branch release/4.2.0_cvs

This commit was manufactured by cvs2svn to create tag

2000-11-20T04:41:45+00:00

'RELENG_4_2_0_RELEASE'.

This commit was manufactured to restore the state of the 4.2-RELEASE image.
Releases prior to 5.3-RELEASE are omitting the secure/ and crypto/ subdirs.

-Wall and minor style(9) cleanups.

1999-12-28T18:13:04+00:00

$Id$ -> $FreeBSD$

1999-08-28T00:22:10+00:00

Add RCS IDs to those files without them.

1999-08-05T12:15:30+00:00

Fix copyrights (s/REGENTS/AUTHOR).

Suggested by:	tg
Approved by:	jb

- Fixed bug where we NULL'd before we freed the data causing a memory leak.

1999-05-14T21:36:16+00:00

Submitted by:	 Ralf S. Engelschall
Obtained from:	PR i386/11713

NULL a pointer after it is freed to avoid trying to free it again.

1998-09-30T06:24:57+00:00

Implement compile time debug support instead of tracking file name and

1998-06-09T23:21:05+00:00

line number every time a file descriptor is locked.

This looks like a big change but it isn't. It should reduce the size
of libc_r and make it run slightly faster.

Simplify the handling of thread specific data. Only track if a key

1998-06-06T07:24:24+00:00

is allocated or not, rather than keeping a count and attempting to
know it it is in-use. POSIX says that once a key is deleted, using the
key again results in undefined behaviour.

Remove some stale code.

1998-05-31T23:47:06+00:00

Pointed out by: Amancio

Change signal model to match POSIX (i.e. one set of signal handlers

1998-04-29T09:59:34+00:00

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!