On Tue, Aug 20, 2019 at 07:08:18PM +0200, Sebastian Siewior wrote: > Bit spinlocks are problematic if PREEMPT_RT is enabled, because they > disable preemption, which is undesired for latency reasons and breaks when > regular spinlocks are taken within the bit_spinlock locked region because > regular spinlocks are converted to 'sleeping spinlocks' on RT. So RT > replaces the bit spinlocks with regular spinlocks to avoid this problem. > Bit spinlocks are also not covered by lock debugging, e.g. lockdep. > > Substitute the BH_Uptodate_Lock bit spinlock with a regular spinlock. > > Signed-off-by: Thomas Gleixner <t...@linutronix.de> > [bigeasy: remove the wrapper and use always spinlock_t]
Uhh ... always grow the buffer_head, even for non-PREEMPT_RT? Why?
