fluencelabs/musl
1
0
Fork 0
mirror of https://github.com/fluencelabs/musl synced 2025-06-24 20:21:59 +00:00
Code Issues Projects Releases Wiki Activity

in synccall, ignore the signal before any threads' signal handlers return

Browse Source 
this protects against deadlock from spurious signals (e.g. sent by
another process) arriving after the controlling thread releases the
other threads from the sync operation.
This commit is contained in:
Rich Felker
2013-09-02 15:16:36 -04:00
parent a731e4103b
commit 3c0501d28c
1 changed files with 4 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
src/thread/synccall.c
View File

@ -71,6 +71,10 @@ void __synccall(void (*func)(void *), void *ctx)
sigqueue(self->pid, SIGSYNCCALL, (union sigval){0}); sigqueue(self->pid, SIGSYNCCALL, (union sigval){0});
while (sem_wait(&chaindone)); while (sem_wait(&chaindone));
sa.sa_flags = 0;
sa.sa_handler = SIG_IGN;
__libc_sigaction(SIGSYNCCALL, &sa, 0);
for (cur=head; cur; cur=cur->next) { for (cur=head; cur; cur=cur->next) {
sem_post(&cur->sem); sem_post(&cur->sem);
while (sem_wait(&cur->sem2)); while (sem_wait(&cur->sem2));
@ -82,10 +86,6 @@ void __synccall(void (*func)(void *), void *ctx)
sem_post(&cur->sem); sem_post(&cur->sem);
} }
sa.sa_flags = 0;
sa.sa_handler = SIG_IGN;
__libc_sigaction(SIGSYNCCALL, &sa, 0);
__syscall(SYS_rt_sigprocmask, SIG_SETMASK, __syscall(SYS_rt_sigprocmask, SIG_SETMASK,
&oldmask, 0, _NSIG/8); &oldmask, 0, _NSIG/8);