Merge branches 'cmpxchg.2024.05.11a', 'kcsan.2024.05.07a', 'lkmm.2024.05.06a', 'rcu-merge.2024.05.01a' and 'tsc.2024.04.09c' into HEAD

cmpxchg.2024.05.11a: Single-byte cmpxchg() emulation and use in csky.
kcsan.2024.05.07a: Add __data_racy type qualifier.
lkmm.2024.05.06a: Linux kernel memory model updates.
rcu-merge.2024.05.01a: RCU commits (via Uladzislau Rezki).
tsc.2024.04.09c: TSC watchdog updates (likely via -tip).