On Fri, May 19, 2017 at 11:39 PM, Yijing Wang <wangyijing@xxxxxxxxxx> wrote: > Now libsas hotplug work is static, LLDD driver queue > the hotplug work into shost->work_q. If LLDD driver > burst post lots hotplug events to libsas, the hotplug > events may pending in the workqueue like > > shost->work_q > new work[PORTE_BYTES_DMAED] --> |[PHYE_LOSS_OF_SIGNAL][PORTE_BYTES_DMAED] -> processing > |<-------wait worker to process-------->| > In this case, a new PORTE_BYTES_DMAED event coming, libsas try to queue it > to shost->work_q, but this work is already pending, so it would be lost. > Finally, libsas delete the related sas port and sas devices, but LLDD driver > expect libsas add the sas port and devices(last sas event). > > This patch remove the static defined hotplug work, and use dynamic work to > avoid missing hotplug events. If we go this route we don't even need: sas_port_event_fns sas_phy_event_fns sas_ha_event_fns ...just specify the target routine directly to INIT_WORK() and remove the indirection. I also think for safety this should use a mempool that guarantees that events can continue to be processed under system memory pressure. Also, have you considered the case when a broken phy starts throwing a constant stream of events? Is there a point at which libsas should stop queuing events and disable the phy?
