riscv/musl - musl - Gitea: Git with a cup of tea

History

Rich Felker 9d44b6460a install dynamic tls synchronously at dlopen, streamline access previously, dynamic loading of new libraries with thread-local storage allocated the storage needed for all existing threads at load-time, precluding late failure that can't be handled, but left installation in existing threads to take place lazily on first access. this imposed an additional memory access and branch on every dynamic tls access, and imposed a requirement, which was not actually met, that the dynamic tlsdesc asm functions preserve all call-clobbered registers before calling C code to to install new dynamic tls on first access. the x86[_64] versions of this code wrongly omitted saving and restoring of fpu/vector registers, assuming the compiler would not generate anything using them in the called C code. the arm and aarch64 versions saved known existing registers, but failed to be future-proof against expansion of the register file. now that we track live threads in a list, it's possible to install the new dynamic tls for each thread at dlopen time. for the most part, synchronization is not needed, because if a thread has not synchronized with completion of the dlopen, there is no way it can meaningfully request access to a slot past the end of the old dtv, which remains valid for accessing slots which already existed. however, it is necessary to ensure that, if a thread sees its new dtv pointer, it sees correct pointers in each of the slots that existed prior to the dlopen. my understanding is that, on most real-world coherency architectures including all the ones we presently support, a built-in consume order guarantees this; however, don't rely on that. instead, the SYS_membarrier syscall is used to ensure that all threads see the stores to the slots of their new dtv prior to the installation of the new dtv. if it is not supported, the same is implemented in userspace via signals, using the same mechanism as __synccall. the __tls_get_addr function, variants, and dynamic tlsdesc asm functions are all updated to remove the fallback paths for claiming new dynamic tls, and are now all branch-free.		7 years ago
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aio	on failed aio submission, set aiocb error and return value	8 years ago
complex	fix incorrect results for catan with some inputs	8 years ago
conf	fix build regression in sysconf for archs with variable page size	8 years ago
crypt	reduce spurious inclusion of libc.h	8 years ago
ctype	reduce spurious inclusion of libc.h	8 years ago
dirent	fail fdopendir for O_PATH file descriptors	7 years ago
env	track all live threads in an AS-safe, fully-consistent linked list	7 years ago
errno	add hidden version of &errno accessor function	8 years ago
exit	split internal lock API out of libc.h, creating lock.h	8 years ago
fcntl	remove spurious inclusion of libc.h for LFS64 ABI aliases	8 years ago
fenv	fix fesetround error checking	8 years ago
include	introduce namespace-safe rwlock aliases; use in pthread_key_create	7 years ago
internal	install dynamic tls synchronously at dlopen, streamline access	7 years ago
ipc	reduce spurious inclusion of libc.h	8 years ago
ldso	install dynamic tls synchronously at dlopen, streamline access	7 years ago
legacy	remove spurious inclusion of libc.h for LFS64 ABI aliases	8 years ago
linux	wireup linux/name_to_handle_at and name_to_handle_at syscalls	8 years ago
locale	locale: ensure dcngettext() preserves errno	7 years ago
malloc	split internal lock API out of libc.h, creating lock.h	8 years ago
math	x86_64: add single instruction fma	8 years ago
misc	add namespace-safe version of getauxval for internal use	8 years ago
mman	remove spurious inclusion of libc.h for LFS64 ABI aliases	8 years ago
mq	use restrict everywhere it's required by c99 and/or posix 2008	14 years ago
multibyte	reduce spurious inclusion of libc.h	8 years ago
network	allow freeaddrinfo of arbitrary sublists of addrinfo list	8 years ago
passwd	halt getspnam[_r] search on error accessing TCB shadow	7 years ago
prng	split internal lock API out of libc.h, creating lock.h	8 years ago
process	track all live threads in an AS-safe, fully-consistent linked list	7 years ago
regex	allow escaped path-separator slashes in glob	8 years ago
sched	move and deduplicate declarations of __vdsosym to make it checkable	8 years ago
search	new tsearch implementation	8 years ago
select	reduce spurious inclusion of libc.h	8 years ago
setjmp	add m68k port	8 years ago
signal	add __timedwait backend workaround for old kernels where futex EINTRs	8 years ago
stat	remove spurious inclusion of libc.h for LFS64 ABI aliases	8 years ago
stdio	fix behavior of gets when input line contains a null byte	7 years ago
stdlib	fix undefined behavior in strto* via FILE buffer pointer abuse	8 years ago
string	fix memccpy to not access buffer past given size	8 years ago
temp	remove spurious inclusion of libc.h for LFS64 ABI aliases	8 years ago
termios	reduce spurious inclusion of libc.h	8 years ago
thread	install dynamic tls synchronously at dlopen, streamline access	7 years ago
time	always block signals for starting new threads, refactor start args	7 years ago
unistd	improve error handling of ttyname_r and isatty	8 years ago