diff options
| -rw-r--r-- | src/thread/__unmapself.c | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/src/thread/__unmapself.c b/src/thread/__unmapself.c index e69de29b..1d3bee1d 100644 --- a/src/thread/__unmapself.c +++ b/src/thread/__unmapself.c @@ -0,0 +1,29 @@ +#include "pthread_impl.h" +#include "atomic.h" +#include "syscall.h" +/* cheat and reuse CRTJMP macro from dynlink code */ +#include "dynlink.h" + +static volatile int lock; +static void *unmap_base; +static size_t unmap_size; +static char shared_stack[256]; + +static void do_unmap() +{ + __syscall(SYS_munmap, unmap_base, unmap_size); + __syscall(SYS_exit); +} + +void __unmapself(void *base, size_t size) +{ + int tid=__pthread_self()->tid; + char *stack = shared_stack + sizeof shared_stack; + stack -= (uintptr_t)stack % 16; + while (lock || a_cas(&lock, 0, tid)) + a_spin(); + __syscall(SYS_set_tid_address, &lock); + unmap_base = base; + unmap_size = size; + CRTJMP(do_unmap, stack); +} |