mirror of https://github.com/torvalds/linux.git
c5bcab7558
Add local_lock_nested_bh() locking. It is based on local_lock_t and the naming follows the preempt_disable_nested() example. For !PREEMPT_RT + !LOCKDEP it is a per-CPU annotation for locking assumptions based on local_bh_disable(). The macro is optimized away during compilation. For !PREEMPT_RT + LOCKDEP the local_lock_nested_bh() is reduced to the usual lock-acquire plus lockdep_assert_in_softirq() - ensuring that BH is disabled. For PREEMPT_RT local_lock_nested_bh() acquires the specified per-CPU lock. It does not disable CPU migration because it relies on local_bh_disable() disabling CPU migration. With LOCKDEP it performans the usual lockdep checks as with !PREEMPT_RT. Due to include hell the softirq check has been moved spinlock.c. The intention is to use this locking in places where locking of a per-CPU variable relies on BH being disabled. Instead of treating disabled bottom halves as a big per-CPU lock, PREEMPT_RT can use this to reduce the locking scope to what actually needs protecting. A side effect is that it also documents the protection scope of the per-CPU variables. Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://patch.msgid.link/20240620132727.660738-3-bigeasy@linutronix.de Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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| .. | ||
| Makefile | ||
| irqflag-debug.c | ||
| lock_events.c | ||
| lock_events.h | ||
| lock_events_list.h | ||
| lockdep.c | ||
| lockdep_internals.h | ||
| lockdep_proc.c | ||
| lockdep_states.h | ||
| locktorture.c | ||
| mcs_spinlock.h | ||
| mutex-debug.c | ||
| mutex.c | ||
| mutex.h | ||
| osq_lock.c | ||
| percpu-rwsem.c | ||
| qrwlock.c | ||
| qspinlock.c | ||
| qspinlock_paravirt.h | ||
| qspinlock_stat.h | ||
| rtmutex.c | ||
| rtmutex_api.c | ||
| rtmutex_common.h | ||
| rwbase_rt.c | ||
| rwsem.c | ||
| semaphore.c | ||
| spinlock.c | ||
| spinlock_debug.c | ||
| spinlock_rt.c | ||
| test-ww_mutex.c | ||
| ww_mutex.h | ||
| ww_rt_mutex.c | ||