Re: [PATCH v5 1/7] scsi: libsas: Use dynamic alloced work to avoid sas event lost

[Hannes Reinecke]

On 12/08/2017 10:42 AM, Jason Yan wrote:
> Now libsas hotplug work is static, every sas event type has its own
> static work, LLDD driver queues the hotplug work into shost->work_q.
> If LLDD driver burst posts 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 use dynamic allocated work to avoid this issue.
> 
> Signed-off-by: Yijing Wang <wangyijing@xxxxxxxxxx>
> CC: John Garry <john.garry@xxxxxxxxxx>
> CC: Johannes Thumshirn <jthumshirn@xxxxxxx>
> CC: Ewan Milne <emilne@xxxxxxxxxx>
> CC: Christoph Hellwig <hch@xxxxxx>
> CC: Tomas Henzl <thenzl@xxxxxxxxxx>
> CC: Dan Williams <dan.j.williams@xxxxxxxxx>
> Signed-off-by: Jason Yan <yanaijie@xxxxxxxxxx>
> ---
>  drivers/scsi/libsas/sas_event.c    | 74 +++++++++++++++++++++++++++++---------
>  drivers/scsi/libsas/sas_init.c     | 27 ++++++++++++--
>  drivers/scsi/libsas/sas_internal.h |  6 ++++
>  drivers/scsi/libsas/sas_phy.c      | 44 +++++------------------
>  drivers/scsi/libsas/sas_port.c     | 18 +++++-----
>  include/scsi/libsas.h              | 17 +++++----
>  6 files changed, 115 insertions(+), 71 deletions(-)
> 
Reviewed-by: Hannes Reinecke <hare@xxxxxxxx>

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		   Teamlead Storage & Networking
hare@xxxxxxx			               +49 911 74053 688
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 NÃrnberg
GF: F. ImendÃrffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton
HRB 21284 (AG NÃrnberg)