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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?2m6PILfeO1A/k+/2Xk9cWJ3fYiYaaO3ZuMwcWKcpv3sdsLYknWn3gNqDN34W?= =?us-ascii?Q?nfi4t9sMfXp1CN0FZv99KPp9DbPxd51KE7IZkQo+66ZTMYSlQA3lkn5zyGhB?= =?us-ascii?Q?W14NyhDzqgfp28p+Iug4J3mADtxoAwd8mS5TkSpwOvQFUw89Uh7CSYQYFru1?= =?us-ascii?Q?PdoHlJ9e6q2b7ClAtw0Il6qh/xTj4qqndAbb8H7ck+oxcbsyqZGCbj2VmQ+j?= =?us-ascii?Q?T0YpU0/Wxt7ekwePKr3rl/f4uLkTtoVUYL26P+vw4zYxjsn/JeeNtGJBtg8m?= =?us-ascii?Q?tGdSeriO+n6AO40tiq2shnTH5cL/woEQDJUWgS/cjOWV8BdyeHjx2H1gT8Yg?= =?us-ascii?Q?yQpjkV9nRFvKiep2wkwpaZXuRnRWRwnk+Rxg2Qu13CLDX6hHVoXgcHyI6D0d?= =?us-ascii?Q?9GN+EbClKPFXW0RHiltEfVGFdq/YJecbCUc/w4yFW1uN/TWs3UoqLPQ5IzKt?= =?us-ascii?Q?owy+Q6mladNbbAmfBDMQi+IAq3BNGILBCT1m3aiiLZs61u7VvBRQ3Qv/nsVF?= =?us-ascii?Q?OMtm8ea0IpwyDG/0pRKysN7ZXi5hbs9Wg+4dpGMjvv/xAoAjqVk45zzqXpGo?= =?us-ascii?Q?36/b+nkMSmnI18q8Ly+eusFMrLvByh9K+KmlVH4Bjn4PD5W063tcel5Rb0vO?= =?us-ascii?Q?Q9nAo0rxaWwOqJdBsBAeP7ytHG3802U4lVS0TPOF1DF+f0qt/umt/1pvTsUP?= =?us-ascii?Q?Dcuo6TFMfa8/NvTzrtEqXjeMj20H55ZL0rgNW7uh3jjIcUSeF8w0VCLI4fyr?= =?us-ascii?Q?uBW8tZANjqI3RLL/rcFZl5Ixa/1D0uVUH8Nwv33dCYDTjR8mOJJBK/H0flvX?= =?us-ascii?Q?hIgDPIrLgabH4ootGRIPtM/j5OWphWzhtKzl6LvlGaoskTNsFWDeTeLIVTBt?= =?us-ascii?Q?ubAQaprpIG4jk+HDkVyM75GUWkx+WZaEQybC0T3IuTG6isFfHpQY8TKHGLmz?= =?us-ascii?Q?PDgTSM9SFva80eF0C6AnoEoLLPzbQ93Sru9I2sXhhKoTgERXmqKbWr6+AJkC?= =?us-ascii?Q?bH8EPboY91DsNkwBoozFf+mkvJTChvDo6QmWIq1SMB4XvcE5XKjz9DXpifln?= =?us-ascii?Q?aFWQhy2jlnFC8ozLMF9bLqO3QLPV2kdxX6IUmjFcTcvMUpopvNMkfq6/RNvS?= =?us-ascii?Q?lrqu/tAPSqZJ82GRaenunbY2rQ7rokUwuEPmcqqO7m5xwUjORL0WBAYgnaAP?= =?us-ascii?Q?i6i6dFQdagDoRwc9sYPl3im2QQKsT2aDBXcmwXxpQP00CxMtz8z/2gfnJIa+?= =?us-ascii?Q?G9TUudqLX4tNBFT3CF77WKlZ4np5TUWv5vnnUYIWVl/K5uLJYG/GHFjnTmKw?= =?us-ascii?Q?BDcvze8oxhZFFtKSLSI4JjH82JXL+OVz9gUdt2prrejT7Ily9cgQAUevs5NF?= =?us-ascii?Q?BD6wgQeInGpfcfsQqcQHA6mph++lSAWVKHpoe54jQ97TzZhKEVppa/0ZJNc/?= =?us-ascii?Q?bB+jnwbgzqsQaaj4FGSzQOxYwNUMSDV7qSiyHvkr+yilFxZv8uRuSHJNHP9l?= =?us-ascii?Q?hoekq6yDKNHAoUSS9vIjg/6bUXWzIkE4WJkQzhbXVG11C/1asB9w3A442UD5?= =?us-ascii?Q?crMnaSftkb1xioMAK90bR9xozkgJp94V6uSevsd9?= X-MS-Exchange-CrossTenant-Network-Message-Id: a984a9ce-97f0-45f5-5388-08dad167dfa1 X-MS-Exchange-CrossTenant-AuthSource: SA1PR11MB6733.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 28 Nov 2022 17:42:09.1481 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: bS22cAMiQmw+UZpr2UXkUtVJkjtFPrpp1uhBHVArr+O+hcKW9tN2hexD0vJNYswp4JXyNeiffCJxEjHuB42SzQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR11MB6066 X-OriginatorOrg: intel.com Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 28, 2022 at 01:51:24PM +0800, Li, Ming wrote: > > On 11/28/2022 12:03 PM, ira.weiny@intel.com wrote: > > From: Ira Weiny > > > > pci_doe_flush_mb() does not work and is currently unused. > > > > It does not work because each struct doe_mb is managed as part of the > > PCI device. They can't go away as long as the PCI device exists. > > pci_doe_flush_mb() was set up to flush the workqueue and prevent any > > further submissions to the mailboxes when the PCI device goes away. > > Unfortunately, this was fundamentally flawed. There was no guarantee > > that a struct doe_mb remained after pci_doe_flush_mb() returned. > > Therefore, the doe_mb state could be invalid when those threads waiting > > on the workqueue were flushed. > > > > Fortunately the current code is safe because all callers make a > > synchronous call to pci_doe_submit_task() and maintain a reference on > > the PCI device. Therefore pci_doe_flush_mb() is effectively unused. > > > > Rather than attempt to fix pci_doe_flush_mb() just remove the dead code > > around pci_doe_flush_mb(). > > > > Cc: Lukas Wunner > > Cc: Jonathan Cameron > > Signed-off-by: Ira Weiny > > Some comments inline. > > > > > --- > > Changes from V2: > > Lukas > > Clarify commit message. > > Jonathan > > Add comment for changed poll interval. > > ... > > > > > -static int pci_doe_wait(struct pci_doe_mb *doe_mb, unsigned long timeout) > > -{ > > - if (wait_event_timeout(doe_mb->wq, > > - test_bit(PCI_DOE_FLAG_CANCEL, &doe_mb->flags), > > - timeout)) > > - return -EIO; > > - return 0; > > -} > > - > > static void pci_doe_write_ctrl(struct pci_doe_mb *doe_mb, u32 val) > > { > > struct pci_dev *pdev = doe_mb->pdev; > > @@ -82,12 +73,9 @@ static int pci_doe_abort(struct pci_doe_mb *doe_mb) > > pci_doe_write_ctrl(doe_mb, PCI_DOE_CTRL_ABORT); > > > > do { > > - int rc; > > u32 val; > > > > - rc = pci_doe_wait(doe_mb, PCI_DOE_POLL_INTERVAL); > > - if (rc) > > - return rc; > > + msleep_interruptible(PCI_DOE_POLL_INTERVAL_MSECS); > > pci_read_config_dword(pdev, offset + PCI_DOE_STATUS, &val); > > Looks like we don't have to use msleep_interruptible() here, can use msleep() directly? I don't know. I think your suggestion below holds here too. Unfortunately that could mask the signal received in the case below. But I think that is going to be rare enough we could ignore it. > > > > > /* Abort success! */ > > @@ -278,11 +266,7 @@ static void doe_statemachine_work(struct work_struct *work) > > signal_task_abort(task, -EIO); > > return; > > } > > - rc = pci_doe_wait(doe_mb, PCI_DOE_POLL_INTERVAL); > > - if (rc) { > > - signal_task_abort(task, rc); > > - return; > > - } > > + msleep_interruptible(PCI_DOE_POLL_INTERVAL_MSECS); > > goto retry_resp; > > } > > I guess that you use msleep_interruptible() here for aborting current task when signals come. > So there should be signal_task_abort() and return when msleep_interruptible() receives a signal. Yes this makes much more sense. Thanks for looking! Ira > > Thanks > Ming > > > > > @@ -383,21 +367,6 @@ static void pci_doe_destroy_workqueue(void *mb) > > destroy_workqueue(doe_mb->work_queue); > > } > > > > -static void pci_doe_flush_mb(void *mb) > > -{ > > - struct pci_doe_mb *doe_mb = mb; > > - > > - /* Stop all pending work items from starting */ > > - set_bit(PCI_DOE_FLAG_DEAD, &doe_mb->flags); > > - > > - /* Cancel an in progress work item, if necessary */ > > - set_bit(PCI_DOE_FLAG_CANCEL, &doe_mb->flags); > > - wake_up(&doe_mb->wq); > > - > > - /* Flush all work items */ > > - flush_workqueue(doe_mb->work_queue); > > -} > > - > > /** > > * pcim_doe_create_mb() - Create a DOE mailbox object > > * > > @@ -450,14 +419,6 @@ struct pci_doe_mb *pcim_doe_create_mb(struct pci_dev *pdev, u16 cap_offset) > > return ERR_PTR(rc); > > } > > > > - /* > > - * The state machine and the mailbox should be in sync now; > > - * Set up mailbox flush prior to using the mailbox to query protocols. > > - */ > > - rc = devm_add_action_or_reset(dev, pci_doe_flush_mb, doe_mb); > > - if (rc) > > - return ERR_PTR(rc); > > - > > rc = pci_doe_cache_protocols(doe_mb); > > if (rc) { > > pci_err(pdev, "[%x] failed to cache protocols : %d\n", >