On 6/3/20 8:49 AM, Ahmed S. Darwish wrote: > For optimized block readers not holding a mutex, the "number of sectors" > 64-bit value is protected from tearing on 32-bit architectures by a > sequence counter. > > Disable preemption before entering that sequence counter's write side > critical section. Otherwise, the read side can preempt the write side > section and spin for the entire scheduler tick. If the reader belongs to > a real-time scheduling class, it can spin forever and the kernel will > livelock. Applied, thanks. -- Jens Axboe
