Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932452AbdIRMzO (ORCPT ); Mon, 18 Sep 2017 08:55:14 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:6064 "EHLO szxga05-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932366AbdIRMzM (ORCPT ); Mon, 18 Sep 2017 08:55:12 -0400 Subject: Re: [PATCH v4 00/11] Enhance libsas hotplug feature References: <1504689314-20072-1-git-send-email-yanaijie@huawei.com> CC: , , , , , , , , , , , , To: Jason Yan , , From: John Garry Message-ID: Date: Mon, 18 Sep 2017 13:54:47 +0100 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.3.0 MIME-Version: 1.0 In-Reply-To: <1504689314-20072-1-git-send-email-yanaijie@huawei.com> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.203.181.152] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A090204.59BFC22C.000E,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2014-11-16 11:51:01, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 40429ac5a7bc739ab9db40212fac3932 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4413 Lines: 104 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(-) >