On 2019-08-09 14:42:26 [+0200], Jan Kara wrote: > Hello, Hi, > This series is derived from Thomas' series to get rid of bit spinlocks in > buffer head code. These patches convert BH_State bit spinlock to an ordinary > spinlock inside struct journal_head and somewhat reduce the critical section > under BH_JournalHead bit spinlock so that it is fine for RT. > > Motivation from original Thomas' series: > > Bit spinlocks are problematic if PREEMPT_RT is enabled. 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. > > Bit spinlocks are also not covered by lock debugging, e.g. lockdep. With > the spinlock substitution in place, they can be exposed via a new config > switch: CONFIG_DEBUG_BIT_SPINLOCKS. > > Ted, can you pick up these patches? Thanks! Has this series been postponed? > Changes since v1: > * Fixed up compilation breakage on UP due to missing linux/spinlock.h include > > Honza Sebastian
