TODO revision 1.2
1 1.2 thorpej Bugs to fix: 2 1.2 thorpej 3 1.2 thorpej - pthread_cond_timedwait() doesn't work if SA's aren't running yet, 4 1.2 thorpej because the alarm system isn't up and running. It would be weird to 5 1.2 thorpej use them that way, but it's perfectly legal. 6 1.2 thorpej - There is a race between pthread_cancel() and 7 1.2 thorpej pthread_cond_broadcast() or pthread_exit() about removing an item 8 1.2 thorpej from the sleep queue. The locking protocols there need a little 9 1.2 thorpej adjustment. 10 1.2 thorpej - pthread_sig.c: pthread__signal_tramp() is broken. It gets a ucontext, 11 1.2 thorpej but then hands off an empty (garbage from stack!) sigcontext to the 12 1.2 thorpej handler. The ucontext MUST be converted to a sigcontext, the handler 13 1.2 thorpej called, and then the sigcontext converted back to ucontext, before the 14 1.2 thorpej ucontext is used to perform the sigreturn-analogue. This is necessary 15 1.2 thorpej for e.g. C++/Java exceptions and some garbage-collectors. 16 1.2 thorpej - pthread_sig.c: pthread__signal_tramp() should be changed so that it is 17 1.2 thorpej easy to add support for SA_SIGINFO later. (Mostly a function signature 18 1.2 thorpej issue.) 19 1.2 thorpej - pthread_sig.c: Come up with a signal trampoline naming convention like 20 1.2 thorpej libc's, so that GDB will have an easier time with things. 21 1.2 thorpej - Consider moving pthread__signal_tramp() to its own file, and building 22 1.2 thorpej it with -fasync-unwind-tables, so that DWARF2 EH unwinding works through 23 1.2 thorpej it. (This is required for e.g. GCC's libjava.) 24 1.2 thorpej - Add locking to ld.elf_so so that multiple threads doing lazy binding 25 1.2 thorpej doesn't trash things. 26 1.2 thorpej - Verify the cancel stub symbol trickery. 27 1.2 thorpej 28 1.2 thorpej 29 1.2 thorpej Interfaces/features to implement: 30 1.2 thorpej - pthread_kill() 31 1.2 thorpej - pthread_atfork() 32 1.2 thorpej - priority scheduling 33 1.2 thorpej - libc integration: 34 1.2 thorpej - foo_r interfaces 35 1.2 thorpej - system integration 36 1.2 thorpej - some macros and prototypes belong in headers other than pthread.h 37 1.2 thorpej 38 1.2 thorpej 39 1.2 thorpej Features that need more/better regression tests: 40 1.2 thorpej - pthread_cond_broadcast() 41 1.2 thorpej - pthread_once() 42 1.2 thorpej - pthread_get/setspecific() 43 1.2 thorpej - signals 44 1.2 thorpej 45 1.2 thorpej 46 1.2 thorpej Things that need fixing: 47 1.2 thorpej - Recycle dead threads for new threads. 48 1.2 thorpej 49 1.2 thorpej Ideas to play with: 50 1.2 thorpej - Explore the trapcontext vs. usercontext distinction in ucontext_t. 51 1.2 thorpej - Get rid of thread structures when too many accumulate (is this 52 1.2 thorpej actually a good idea?) 53 1.2 thorpej - Adaptive spin/sleep locks for mutexes. 54 1.2 thorpej - Currently, each thread uses two real pages of memory: one at the top 55 1.2 thorpej of the stack for actual stack data, and one at the bottom for the 56 1.2 thorpej pthread_st. If we can get suitable space above the initial stack for 57 1.2 thorpej main(), we can cut this to one page per thread. Perhaps crt0 should 58 1.2 thorpej do something different (give us more space) if libpthread is linked 59 1.2 thorpej in? 60 1.2 thorpej - Figure out whether/how to expose the inline version of 61 1.2 thorpej pthread_self(). 62 1.2 thorpej - Along the same lines, figure out whether/how to use registers reserved 63 1.2 thorpej in the ABI for thread-specific-data to implement pthread_self(). 64
Indexes created Tue Sep 23 02:09:52 GMT 2025