X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=README.threads;h=136b156e7ff897546c65cabd968c337dfa150324;hb=2680586ee66b8de4d2b5f26a2013220f2bec9d5f;hp=db54f7a1ceabed8f6c9d25a7cb1e9f8326cf5fe5;hpb=ce637636a41b2fef0be4daa6d9d27b84e0907a74;p=p5sagit%2Fp5-mst-13.2.git diff --git a/README.threads b/README.threads index db54f7a..136b156 100644 --- a/README.threads +++ b/README.threads @@ -1,12 +1,22 @@ +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. @@ -15,48 +25,61 @@ running one of the following: 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 @@ -71,21 +94,23 @@ For IRIX: Thanks to Hannu Napari 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 -DUSE_THREADS -DNEED_PTHREAD_INIT -DDEBUGGING to ccflags and cppflags - Change optimize to -g + 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 @@ -134,11 +159,8 @@ libraries were not compiled to be thread-aware). 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. @@ -147,13 +169,13 @@ haven't tracked down yet) and there are very probably others too. 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 @@ -259,3 +281,9 @@ ZOMBIE ----------------------------> DEAD Malcolm Beattie mbeattie@sable.ox.ac.uk Last updated: 27 November 1997 + +Configure-related info updated 16 July 1998 by +Andy Dougherty + +Other minor updates 10 Feb 1999 by +Gurusamy Sarathy