peterz@infradead.org 0f4b5f9722 futex: Add sys_futex_requeue()
Finish off the 'simple' futex2 syscall group by adding
sys_futex_requeue(). Unlike sys_futex_{wait,wake}() its arguments are
too numerous to fit into a regular syscall. As such, use struct
futex_waitv to pass the 'source' and 'destination' futexes to the
syscall.

This syscall implements what was previously known as FUTEX_CMP_REQUEUE
and uses {val, uaddr, flags} for source and {uaddr, flags} for
destination.

This design explicitly allows requeueing between different types of
futex by having a different flags word per uaddr.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20230921105248.511860556@noisy.programming.kicks-ass.net
2023-09-21 19:22:10 +02:00
..
2023-08-21 13:46:25 -07:00
2023-09-07 10:30:17 -07:00
2023-09-21 19:22:10 +02:00
2023-06-30 09:20:08 -07:00
2023-09-07 10:30:17 -07:00
2022-10-02 18:06:03 +09:00