Quoting Sebastian Andrzej Siewior (2019-10-17 09:40:01) > The locks (active.lock and rq->lock) need to be taken with disabled > interrupts. This is done in i915_request_retire() by disabling the > interrupts independently of the locks itself. > While local_irq_disable()+spin_lock() equals spin_lock_irq() on vanilla > it does not on PREEMPT_RT. > Chris Wilson confirmed that local_irq_disable() was just introduced as > an optimisation to avoid enabling/disabling interrupts during > lock/unlock combo. > > Enable/disable interrupts as part of the locking instruction. > > Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> Reviewed-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> -Chris _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
