Commit 7ffc9ec8 authored by Paul E. McKenney's avatar Paul E. McKenney
Browse files

kvfree_rcu: Make krc_this_cpu_unlock() use raw_spin_unlock_irqrestore() 



The krc_this_cpu_unlock() function does a raw_spin_unlock() immediately
followed by a local_irq_restore().  This commit saves a line of code by
merging them into a raw_spin_unlock_irqrestore().  This transformation
also reduces scheduling latency because raw_spin_unlock_irqrestore()
responds immediately to a reschedule request.  In contrast,
local_irq_restore() does a scheduling-oblivious enabling of interrupts.

Reported-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: default avatarPaul E. McKenney <paulmck@kernel.org>
parent b01b4050

kernel/rcu/tree.c

+1 −2
Original line number Original line Diff line number Diff line
@@ -3229,8 +3229,7 @@ krc_this_cpu_lock(unsigned long *flags) 
static inline void

static inline void

krc_this_cpu_unlock(struct kfree_rcu_cpu *krcp, unsigned long flags)

krc_this_cpu_unlock(struct kfree_rcu_cpu *krcp, unsigned long flags)

{

{

	raw_spin_unlock(&krcp->lock);

	raw_spin_unlock_irqrestore(&krcp->lock, flags);

	local_irq_restore(flags);

}

}





static inline struct kvfree_rcu_bulk_data *

static inline struct kvfree_rcu_bulk_data *