Re: [PATCH tip/core/rcu 03/17] signal: Explain local_irq_save() call

2014-07-08 Thread Paul E. McKenney
On Tue, Jul 08, 2014 at 05:01:51PM +0800, Lai Jiangshan wrote: > On 07/08/2014 06:38 AM, Paul E. McKenney wrote: > > From: "Paul E. McKenney" > > > > The explicit local_irq_save() in __lock_task_sighand() is needed to avoid > > a potential deadlock condition, as noted in a841796f11c90d53 (signal:

Re: [PATCH tip/core/rcu 03/17] signal: Explain local_irq_save() call

2014-07-08 Thread Lai Jiangshan
On 07/08/2014 06:38 AM, Paul E. McKenney wrote: > From: "Paul E. McKenney" > > The explicit local_irq_save() in __lock_task_sighand() is needed to avoid > a potential deadlock condition, as noted in a841796f11c90d53 (signal: > align __lock_task_sighand() irq disabling and RCU). However, someone

[PATCH tip/core/rcu 03/17] signal: Explain local_irq_save() call

2014-07-07 Thread Paul E. McKenney
From: "Paul E. McKenney" The explicit local_irq_save() in __lock_task_sighand() is needed to avoid a potential deadlock condition, as noted in a841796f11c90d53 (signal: align __lock_task_sighand() irq disabling and RCU). However, someone reading the code might be forgiven for concluding that thi