Hi, Bart: 2018-03-02 7:11 GMT+08:00 Bart Van Assche <Bart.VanAssche@xxxxxxx>: > On Mon, 2017-06-05 at 17:37 +0800, Ganesh Mahendran wrote: >> In android system, when there are lots of threads running. Thread A >> holding *host_busy* count is easily to be preempted, and if at the >> same time, thread B set *host_blocked*, then all other threads will >> be io blocked. > > Hello Ganesh, > > Have you considered to insert preempt_disable() and preempt_enable() calls > where necessary to achieve the same effect? I think that would result in a > much less intrusive patch. Yes, preempt_disable()preempt_enable will also achieve the same effect. But I just think preempt_disable()preempt_enable may be a little heavy for this problem which can be fixed by increaseing {host|target|device}_busy count after dispatch cmd. Thanks. > > Thanks, > > Bart. > >