On 08/12/2017 09:42, Jason Yan wrote:
Now the libsas hotplug has some issues, Dan Williams report
a similar bug here before
https://www.mail-archive.com/linux-scsi@vger.kernel.org/msg39187.html
Hi Martin, James,
At this point we feel that we have a decent solution to the
long-standing libsas hotplug issues.
Hannes has kindly reviewed the series.
Can you let us know what else you require for acceptance? More
independent review or testing?
Thanks,
John
The issues we have found
1. if LLDD burst reports lots of phy-up/phy-down sas events, some events
may lost because a same sas events is pending now, finally libsas topo
may different the hardware.
2. receive a phy down sas event, libsas call sas_deform_port to remove
devices, it would first delete the sas port, then put a destruction
discovery event in a new work, and queue it at the tail of workqueue,
once the sas port be deleted, its children device will be deleted too,
when the destruction work start, it will found the target device has
been removed, and report a sysfs warnning.
3. since a hotplug process will be devided into several works, if a phy up
sas event insert into phydown works, like
destruction work ---> PORTE_BYTES_DMAED (sas_form_port)
---->PHYE_LOSS_OF_SIGNAL
the hot remove flow would broken by PORTE_BYTES_DMAED event, it's not
we expected, and issues would occur.
v4->v5: -process only one expander's revalidation in sas_ex_revalidate_domain()
-notify event PORTE_BROADCAST_RCVD in sas_enable_revalidation()
v3->v4: -use dynamic alloced work and support shutting down the phy if active
event reached the threshold
-use flush_workqueue instead of wait-completion to process discover
events synchronously
-direct call probe and destruct function
v2->v3: some code improvements suggested by Johannes and John,
split v2 patch 2 into several small pathes.
v1->v2: some code improvements suggested by John Garry
Jason Yan (7):
scsi: libsas: Use dynamic alloced work to avoid sas event lost
scsi: libsas: shut down the PHY if events reached the threshold
scsi: libsas: make the event threshold configurable
scsi: libsas: Use new workqueue to run sas event and disco event
scsi: libsas: use flush_workqueue to process disco events
synchronously
scsi: libsas: direct call probe and destruct
scsi: libsas: notify event PORTE_BROADCAST_RCVD in
sas_enable_revalidation()
drivers/scsi/hisi_sas/hisi_sas_main.c | 6 ++
drivers/scsi/libsas/sas_ata.c | 1 -
drivers/scsi/libsas/sas_discover.c | 34 ++++++-----
drivers/scsi/libsas/sas_event.c | 86 ++++++++++++++++++++-------
drivers/scsi/libsas/sas_expander.c | 8 +--
drivers/scsi/libsas/sas_init.c | 107 +++++++++++++++++++++++++++++++++-
drivers/scsi/libsas/sas_internal.h | 7 +++
drivers/scsi/libsas/sas_phy.c | 69 +++++++++++-----------
drivers/scsi/libsas/sas_port.c | 25 ++++----
include/scsi/libsas.h | 30 +++++++---
include/scsi/scsi_transport_sas.h | 1 +
11 files changed, 277 insertions(+), 97 deletions(-)
