+NOTE
+
+Threading is a highly experimental feature. There are still a
+few race conditions that show up under high contention on SMP
+machines. Internal implementation is still subject to changes.
+It is not recommended for production use at this time.
+
Building
If you want to build with multi-threading support and you are
running one of the following:
+
* Linux 2.x (with the LinuxThreads library installed: that's
the linuxthreads and linuxthreads-devel RPMs for RedHat)
* Digital UNIX 4.x
+ * Digital UNIX 3.x (Formerly DEC OSF/1), see additional note below
+
* Solaris 2.x for recentish x (2.5 is OK)
* IRIX 6.2 or newer. 6.2 will require a few os patches.
IRIX 6.3 and up should be OK. See lower down for patch details.
then you should be able to use
- ./Configure -Dusethreads -Doptimize=-g -ders
+
+ ./Configure -Dusethreads -des
make
+
and ignore the rest of this "Building" section. If it doesn't
work or you are using another platform which you believe supports
-POSIX.1c threads then read on.
-
-Omit the -e from your ./Configure arguments. For example, use
- ./Configure -drs
-When it offers to let you change config.sh, do so. If you already
-have a config.sh then you can edit it and do
- ./Configure -S
-to propagate the required changes.
-In ccflags, insert -DUSE_THREADS (and probably -DDEBUGGING since
-that's what I've been building with). Also insert any other
-arguments in there that your compiler needs to use POSIX threads.
-Change optimize to -g to give you better debugging information.
-Include any necessary explicit libraries in libs and change
-ldflags if you need any linker flags instead or as well.
-
-More explicitly, for Linux (when using the standard kernel-threads
-based LinuxThreads library):
- Add -DUSE_THREADS -D_REENTRANT -DDEBUGGING to ccflags and cppflags
- Add -lpthread to libs
- Change optimize to -g
+POSIX.1c threads then read on. Additional information may be in
+a platform-specific "hints" file in the hints/ subdirectory.
+
+On other platforms that use Configure to build perl, omit the -d
+from your ./Configure arguments. For example, use:
+
+ ./Configure -Dusethreads
+
+When Configure prompts you for ccflags, insert any other arguments in
+there that your compiler needs to use POSIX threads. When Configure
+prompts you for linking flags, include any flags required for
+threading (usually nothing special is required here). Finally, when
+COnfigure prompts you for libraries, include any necessary libraries
+(e.g. -lpthread). Pay attention to the order of libraries. It is
+probably necessary to specify your threading library *before* your
+standard C library, e.g. it might be necessary to have -lpthread -lc,
+instead of -lc -lpthread.
+
+Once you have specified all your compiler flags, you can have Configure
+accept all the defaults for the remainder of the session by typing &-d
+at any Configure prompt.
+
+Some additional notes (some of these may be obsolete now, other items
+may be handled automatically):
+
For Digital Unix 4.x:
- Add -pthread -DUSE_THREADS -DDEBUGGING to ccflags
- Add -DUSE_THREADS -DDEBUGGING to cppflags
+ Add -pthread to ccflags
Add -pthread to ldflags
- Change optimize to -g
Add -lpthread -lc_r to lddlflags
+
For some reason, the extra includes for pthreads make Digital UNIX
complain fatally about the sbrk() delcaration in perl's malloc.c
- so use the native malloc as follows:
- Change usemymalloc to n
- Zap mallocobj and mallocsrc (foo='')
- Change d_mymalloc to undef
-For Solaris, do the same as for Linux above.
+ so use the native malloc, e.g. sh Configure -Uusemymalloc, or
+ manually edit your config.sh as follows:
+ Change usemymalloc to n
+ Zap mallocobj and mallocsrc (foo='')
+ Change d_mymalloc to undef
+
+For Digital Unix 3.x (Formerly DEC OSF/1):
+ Add -DOLD_PTHREADS_API to ccflags
+ If compiling with the GNU cc compiler, remove -thread from ccflags
+
+ (The following should be done automatically if you call Configure
+ with the -Dusethreads option).
+ Add -lpthread -lmach -lc_r to libs (in the order specified).
+
For IRIX:
- Add -DUSE_THREADS -DDEBUGGING to ccflags
- Add -DUSE_THREADS -DDEBUGGING to cppflags
+ (This should all be done automatically by the hint file).
Add -lpthread to libs
- Change optimize to -g
For IRIX 6.2, you have to have the following patches installed:
1404 Irix 6.2 Posix 1003.1b man pages
1645 IRIX 6.2 & 6.3 POSIX header file updates
For IRIX 6.3 and 6.4 the pthreads should work out of the box.
Thanks to Hannu Napari <Hannu.Napari@hut.fi> for the IRIX
pthreads patches information.
+For AIX:
+ (This should all be done automatically by the hint file).
+ Change cc to xlc_r or cc_r.
+ Add -DNEED_PTHREAD_INIT to ccflags and cppflags
+ Add -lc_r to libswanted
+ Change -lc in lddflags to be -lpthread -lc_r -lc
+
+For Win32:
+ See README.win32, and the notes at the beginning of win32/Makefile
+ or win32/makefile.mk.
Now you can do a
make
O/S specific bugs
-Solaris qsort uses a hidden mutex for synchronisation. If you die()
-while doing a sort() then the resulting longjmp() leaves the mutex
-locked so you get a deadlock the next time you try to sort().
+Irix 6.2: See the Irix warning above.
LinuxThreads 0.5 has a bug which can cause file descriptor 0 to be
closed after a fork() leading to many strange symptoms. Version 0.6
Bugs
* FAKE_THREADS should produce a working perl but the Thread
-extension won't build with it yet.
-
-* There's a known memory leak (curstack isn't freed at the end
-of each thread because it causes refcount problems that I
-haven't tracked down yet) and there are very probably others too.
+extension won't build with it yet. (FAKE_THREADS has not been
+tested at all in recent times.)
* There may still be races where bugs show up under contention.
Debugging
-Use the -DL command-line option to turn on debugging of the
+Use the -DS command-line option to turn on debugging of the
multi-threading code. Under Linux, that also turns on a quick
hack I did to grab a bit of extra information from segfaults.
If you have a fancier gdb/threads setup than I do then you'll
have to delete the lines in perl.c which say
#if defined(DEBUGGING) && defined(USE_THREADS) && defined(__linux__)
- DEBUG_L(signal(SIGSEGV, (void(*)(int))catch_sigsegv););
+ DEBUG_S(signal(SIGSEGV, (void(*)(int))catch_sigsegv););
#endif
Malcolm Beattie
mbeattie@sable.ox.ac.uk
Last updated: 27 November 1997
+
+Configure-related info updated 16 July 1998 by
+Andy Dougherty <doughera@lafayette.edu>
+
+Other minor updates 10 Feb 1999 by
+Gurusamy Sarathy
projects / p5sagit/p5-mst-13.2.git / blobdiff