Reviewed-by: Kenji Kaneshige <kaneshige.kenji@xxxxxxxxxxxxxx> > -----Original Message----- > From: Yijing Wang [mailto:wangyijing@xxxxxxxxxx] > Sent: Monday, November 12, 2012 6:17 PM > To: Bjorn Helgaas; Kaneshige, Kenji/金重 憲治; Yinghai Lu; Rafael; Rusty Russell; Mauro Carvalho Chehab; Oliver Neukum; > jiang.liu@xxxxxxxxxx > Cc: linux-pci@xxxxxxxxxxxxxxx; Hanjun Guo; Yijing Wang > Subject: [PATCH -v3] PCI, pciehp: make every slot have its own workqueue to avoid deadlock > > Currently, pciehp use global pciehp_wq to handle hotplug event from hardware. > Hot remove path will be blocked if a hotplug slot connected a IO-BOX(composed of PCIe > Switch and some slots which support hotplug). The hot removed work was queued into > pciehp_wq. But in the hot-remove path, pciehp driver would flush pciehp_wq when > the pcie port(support pciehp) was removed. In this case the hot-remove path blocked. > This patch remove the global pciehp_wq and create a new workqueue for every slot to > avoid above problem. > > -+-[0000:40]-+-00.0-[0000:41]-- > | +-01.0-[0000:42]--+-00.0 Intel Corporation 82576 Gigabit Network Connection > | | \-00.1 Intel Corporation 82576 Gigabit Network Connection > | +-03.0-[0000:43]----00.0 LSI Logic / Symbios Logic SAS1064ET PCI-Express Fusion-MPT SAS > | +-04.0-[0000:44]-- > | +-05.0-[0000:45]-- > | +-07.0-[0000:46-4f]----00.0-[0000:47-4f]--+-04.0-[0000:48-49]----00.0-[0000:49]-- > | |(hotplug slot) +-08.0-[0000:4a]-- > | | +-09.0-[0000:4b]-- > | | +-10.0-[0000:4c]-- > | | +-11.0-[0000:4d]-- > | | +-14.0-[0000:4e]-- > | | \-15.0-[0000:4f]--+-00.0 Intel Corporation 82576 Gigabit > Network Connection > | | (hotplug slot) \-00.1 Intel Corporation 82576 Gigabit > Network Connection > > > Signed-off-by: Yijing Wang <wangyijing@xxxxxxxxxx> > --- > drivers/pci/hotplug/pciehp.h | 2 +- > drivers/pci/hotplug/pciehp_core.c | 11 ++--------- > drivers/pci/hotplug/pciehp_ctrl.c | 8 ++++---- > drivers/pci/hotplug/pciehp_hpc.c | 11 ++++++++++- > 4 files changed, 17 insertions(+), 15 deletions(-) > > diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h > index 26ffd3e..2c113de 100644 > --- a/drivers/pci/hotplug/pciehp.h > +++ b/drivers/pci/hotplug/pciehp.h > @@ -44,7 +44,6 @@ extern bool pciehp_poll_mode; > extern int pciehp_poll_time; > extern bool pciehp_debug; > extern bool pciehp_force; > -extern struct workqueue_struct *pciehp_wq; > > #define dbg(format, arg...) \ > do { \ > @@ -78,6 +77,7 @@ struct slot { > struct hotplug_slot *hotplug_slot; > struct delayed_work work; /* work for button event */ > struct mutex lock; > + struct workqueue_struct *wq; > }; > > struct event_info { > diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c > index 916bf4f..0914211 100644 > --- a/drivers/pci/hotplug/pciehp_core.c > +++ b/drivers/pci/hotplug/pciehp_core.c > @@ -42,7 +42,6 @@ bool pciehp_debug; > bool pciehp_poll_mode; > int pciehp_poll_time; > bool pciehp_force; > -struct workqueue_struct *pciehp_wq; > > #define DRIVER_VERSION "0.4" > #define DRIVER_AUTHOR "Dan Zink <dan.zink@xxxxxxxxxx>, Greg Kroah-Hartman <greg@xxxxxxxxx>, Dely Sy > <dely.l.sy@xxxxxxxxx>" > @@ -340,18 +339,13 @@ static int __init pcied_init(void) > { > int retval = 0; > > - pciehp_wq = alloc_workqueue("pciehp", 0, 0); > - if (!pciehp_wq) > - return -ENOMEM; > - > pciehp_firmware_init(); > retval = pcie_port_service_register(&hpdriver_portdrv); > dbg("pcie_port_service_register = %d\n", retval); > info(DRIVER_DESC " version: " DRIVER_VERSION "\n"); > - if (retval) { > - destroy_workqueue(pciehp_wq); > + if (retval) > dbg("Failure to register service\n"); > - } > + > return retval; > } > > @@ -359,7 +353,6 @@ static void __exit pcied_cleanup(void) > { > dbg("unload_pciehpd()\n"); > pcie_port_service_unregister(&hpdriver_portdrv); > - destroy_workqueue(pciehp_wq); > info(DRIVER_DESC " version: " DRIVER_VERSION " unloaded\n"); > } > > diff --git a/drivers/pci/hotplug/pciehp_ctrl.c b/drivers/pci/hotplug/pciehp_ctrl.c > index 27f4429..38f0186 100644 > --- a/drivers/pci/hotplug/pciehp_ctrl.c > +++ b/drivers/pci/hotplug/pciehp_ctrl.c > @@ -49,7 +49,7 @@ static int queue_interrupt_event(struct slot *p_slot, u32 event_type) > info->p_slot = p_slot; > INIT_WORK(&info->work, interrupt_event_handler); > > - queue_work(pciehp_wq, &info->work); > + queue_work(p_slot->wq, &info->work); > > return 0; > } > @@ -344,7 +344,7 @@ void pciehp_queue_pushbutton_work(struct work_struct *work) > kfree(info); > goto out; > } > - queue_work(pciehp_wq, &info->work); > + queue_work(p_slot->wq, &info->work); > out: > mutex_unlock(&p_slot->lock); > } > @@ -377,7 +377,7 @@ static void handle_button_press_event(struct slot *p_slot) > if (ATTN_LED(ctrl)) > pciehp_set_attention_status(p_slot, 0); > > - queue_delayed_work(pciehp_wq, &p_slot->work, 5*HZ); > + queue_delayed_work(p_slot->wq, &p_slot->work, 5*HZ); > break; > case BLINKINGOFF_STATE: > case BLINKINGON_STATE: > @@ -439,7 +439,7 @@ static void handle_surprise_event(struct slot *p_slot) > else > p_slot->state = POWERON_STATE; > > - queue_work(pciehp_wq, &info->work); > + queue_work(p_slot->wq, &info->work); > } > > static void interrupt_event_handler(struct work_struct *work) > diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c > index 13b2eaf..b34418d 100644 > --- a/drivers/pci/hotplug/pciehp_hpc.c > +++ b/drivers/pci/hotplug/pciehp_hpc.c > @@ -773,23 +773,32 @@ static void pcie_shutdown_notification(struct controller *ctrl) > static int pcie_init_slot(struct controller *ctrl) > { > struct slot *slot; > + char name[32]; > > slot = kzalloc(sizeof(*slot), GFP_KERNEL); > if (!slot) > return -ENOMEM; > + > + snprintf(name, sizeof(name), "pciehp-%u", PSN(ctrl)); > + slot->wq = create_singlethread_workqueue(name); > + if (!slot->wq) > + goto abort; > > slot->ctrl = ctrl; > mutex_init(&slot->lock); > INIT_DELAYED_WORK(&slot->work, pciehp_queue_pushbutton_work); > ctrl->slot = slot; > return 0; > +abort: > + kfree(slot); > + return -ENOMEM; > } > > static void pcie_cleanup_slot(struct controller *ctrl) > { > struct slot *slot = ctrl->slot; > cancel_delayed_work(&slot->work); > - flush_workqueue(pciehp_wq); > + destroy_workqueue(slot->wq); > kfree(slot); > } > > -- > 1.7.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
