set_robust_list (nr 273)

Linux Signature

long set_robust_list(struct robust_list_head *head, size_t len);

Description

Registers a list of robust futexes with the kernel. If a thread exits while holding a robust futex, the kernel marks it as dead and wakes waiters, preventing permanent deadlocks.

Current Implementation

Always returns 0 (success) without recording anything. Both arguments are ignored.

This is sufficient for musl’s startup, which registers a robust list as part of thread initialisation.

Source: osl/src/syscalls/mod.rs — inline stub in syscall_dispatch

Future Work

• Store the robust list head pointer in the thread structure.
• On thread exit, walk the robust list and wake any futex waiters on held locks.
• Implement get_robust_list (nr 274) for completeness.