Re: [PATCH v4 00/11] Enhance libsas hotplug feature
On 06/09/2017 10:15, Jason Yan wrote:
Hello all, Yijing Wang handed over this topic to me. We are working
on it the last two months. We have tested the patchset for a long
time. Here is the new version.
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
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 divided 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.
I have tried to verify PM suspend/resume feature with this patchset to
ensure that it is not broken.
Since our hisi_sas driver does not support PM yet, I have got my hands
on an adaptec card which uses pm8001 driver (it's vendor 9065, device
8088) to test.
So in the PM resume, sometimes I find the console locks up with and
without this patchset. In these cases, I find this log:
[ 59.344266] pm80xx pm80xx_chip_init 1098:Firmware is not ready!
Is this a known issue? Should we have a chip reset in all cases in the
resume code, marked ***:
static int pm8001_pci_resume(struct pci_dev *pdev)
{
...
rc = pci_go_44(pdev);
if (rc)
goto err_out_disable;
/* chip soft rst only for spc */
if (pm8001_ha->chip_id == chip_8001) { HERE
PM8001_CHIP_DISP->chip_soft_rst(pm8001_ha);
PM8001_INIT_DBG(pm8001_ha,
pm8001_printk("chip soft reset successful\n"));
}
rc = PM8001_CHIP_DISP->chip_init(pm8001_ha);
if (rc)
goto err_out_disable;
...
}
John
v3->v4: -get rid of unused ha event and do some cleanup
-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
-other small code improvements
v2->v3: some code improvements suggested by Johannes and John,
split v2 patch 2 into several small patches.
v1->v2: some code improvements suggested by John Garry
Jason Yan (10):
libsas: kill useless ha_event and do some cleanup
libsas: remove the numbering for each event enum
libsas: remove unused port_gone_completion and DISCE_PORT_GONE
libsas: rename notify_port_event() for consistency
libsas: Use dynamic alloced work to avoid sas event lost
libsas: shut down the PHY if events reached the threshold
libsas: make the event threshold configurable
libsas: Use new workqueue to run sas event and disco event
libsas: libsas: use flush_workqueue to process disco events
synchronously
libsas: direct call probe and destruct
chenxiang (1):
libsas: add event to defer list tail instead of head when draining
drivers/scsi/aic94xx/aic94xx_hwi.c| 3 -
drivers/scsi/hisi_sas/hisi_sas_main.c | 7 ++-
drivers/scsi/libsas/sas_ata.c | 1 -
drivers/scsi/libsas/sas_discover.c| 36 +++-
drivers/scsi/libsas/sas_dump.c| 10
drivers/scsi/libsas/sas_dump.h| 1 -
drivers/scsi/libsas/sas_event.c | 97 +++-
drivers/scsi/libsas/sas_expander.c| 2 +-
drivers/scsi/libsas/sas_init.c| 101 +-
drivers/scsi/libsas/sas_internal.h| 7 +++
drivers/scsi/libsas/sas_phy.c | 73
drivers/scsi/libsas/sas_port.c| 25 +
include/scsi/libsas.h | 81 ---
include/scsi/scsi_transport_sas.h | 1 +
14 files changed, 270 insertions(+), 175 deletions(-)
Re: [PATCH v4 00/11] Enhance libsas hotplug feature
Jason, > Yijing Wang handed over this topic to me. We are working on it the > last two months. We have tested the patchset for a long time. Here is > the new version. Applied patches 1-4 and 11 to 4.15/scsi-queue. I suggest you resubmit the rest to get them back on people's radar. -- Martin K. Petersen Oracle Linux Engineering
Re: [PATCH v4 00/11] Enhance libsas hotplug feature
On 2017/9/6 21:22, Christoph Hellwig wrote: On Wed, Sep 06, 2017 at 02:07:57PM +0100, John Garry wrote: Regardless of the fate of the rest of the patches in this series, I think patches 1,2,3,4,11/11 can be taken in isolation (subject to review, of course). It would save maintaining them out-of-tree. I did a quick review of those and they all look fine to me. I'll try to find some time to review the real changes in the next days. . Thank you very much and I'm looking forward to your suggestions of the real changes.
Re: [PATCH v4 00/11] Enhance libsas hotplug feature
On Wed, Sep 06, 2017 at 02:07:57PM +0100, John Garry wrote: > Regardless of the fate of the rest of the patches in this series, I think > patches 1,2,3,4,11/11 can be taken in isolation (subject to review, of > course). It would save maintaining them out-of-tree. I did a quick review of those and they all look fine to me. I'll try to find some time to review the real changes in the next days.
Re: [PATCH v4 00/11] Enhance libsas hotplug feature
On 06/09/2017 10:15, Jason Yan wrote: Hello all, Yijing Wang handed over this topic to me. We are working on it the last two months. We have tested the patchset for a long time. Here is the new version. 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 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 divided 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. v3->v4: -get rid of unused ha event and do some cleanup -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 -other small code improvements v2->v3: some code improvements suggested by Johannes and John, split v2 patch 2 into several small patches. v1->v2: some code improvements suggested by John Garry Jason Yan (10): libsas: kill useless ha_event and do some cleanup libsas: remove the numbering for each event enum libsas: remove unused port_gone_completion and DISCE_PORT_GONE libsas: rename notify_port_event() for consistency libsas: Use dynamic alloced work to avoid sas event lost libsas: shut down the PHY if events reached the threshold libsas: make the event threshold configurable libsas: Use new workqueue to run sas event and disco event libsas: libsas: use flush_workqueue to process disco events synchronously libsas: direct call probe and destruct chenxiang (1): libsas: add event to defer list tail instead of head when draining Regardless of the fate of the rest of the patches in this series, I think patches 1,2,3,4,11/11 can be taken in isolation (subject to review, of course). It would save maintaining them out-of-tree. John drivers/scsi/aic94xx/aic94xx_hwi.c| 3 - drivers/scsi/hisi_sas/hisi_sas_main.c | 7 ++- drivers/scsi/libsas/sas_ata.c | 1 - drivers/scsi/libsas/sas_discover.c| 36 +++- drivers/scsi/libsas/sas_dump.c| 10 drivers/scsi/libsas/sas_dump.h| 1 - drivers/scsi/libsas/sas_event.c | 97 +++- drivers/scsi/libsas/sas_expander.c| 2 +- drivers/scsi/libsas/sas_init.c| 101 +- drivers/scsi/libsas/sas_internal.h| 7 +++ drivers/scsi/libsas/sas_phy.c | 73 drivers/scsi/libsas/sas_port.c| 25 + include/scsi/libsas.h | 81 --- include/scsi/scsi_transport_sas.h | 1 + 14 files changed, 270 insertions(+), 175 deletions(-)
