| Message ID | 1351667452-9952-1-git-send-email-wangyijing@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
Let me confirm the problem. My understanding of the problem is below.
Is my understanding correct?
- Your hardware has nested PCIe hotplug slots like below.
--<slot A>--<Slot B>
- Hot-removal request (attention button event) comes to <slot A>
- Pciehp driver queue the hot-removal work
- This hot-removal work try to remove <slot B>
- To remove <slot B>, pciehp flush the pciehp_wq, but it never finishes
because hot-removal work is in progress. ===> deadlock
Regards,
Kenji Kaneshige
> -----Original Message-----
> From: Yijing Wang [mailto:wangyijing@huawei.com]
> Sent: Wednesday, October 31, 2012 4:11 PM
> To: Bjorn Helgaas; Yinghai Lu; Kaneshige, Kenji/?? ??; Rafael; Rusty
> Russell; Mauro Carvalho Chehab; Oliver Neukum
> Cc: linux-pci@vger.kernel.org; Hanjun Guo; jiang.liu@huawei.com; Yijing
> Wang
> Subject: [RFC][PATCH] 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, eg.PLX8696). 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@huawei.com>
> ---
> 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 | 14 ++++++++++++--
> 4 files changed, 19 insertions(+), 16 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@compaq.com>, Greg
> Kroah-Hartman <greg@kroah.com>, Dely Sy <dely.l.sy@intel.com>"
> @@ -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..8e5e571 100644
> --- a/drivers/pci/hotplug/pciehp_hpc.c
> +++ b/drivers/pci/hotplug/pciehp_hpc.c
> @@ -773,23 +773,33 @@ 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), "pciehpd_%s",
> + pci_name(ctrl->pcie->port));
> + 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 -1;
> }
>
> static void pcie_cleanup_slot(struct controller *ctrl)
> {
> struct slot *slot = ctrl->slot;
> cancel_delayed_work(&slot->work);
> - flush_workqueue(pciehp_wq);
> + flush_workqueue(slot->wq);
> + destroy_workqueue(slot->wq);
> kfree(slot);
> }
>
> --
> 1.7.1
>
--
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On 2012/10/31 17:20, Kaneshige, Kenji wrote: > Let me confirm the problem. My understanding of the problem is below. > Is my understanding correct? > Yes?exactly. > - Your hardware has nested PCIe hotplug slots like below. > > --<slot A>--<Slot B> > > - Hot-removal request (attention button event) comes to <slot A> > - Pciehp driver queue the hot-removal work > - This hot-removal work try to remove <slot B> > - To remove <slot B>, pciehp flush the pciehp_wq, but it never finishes > because hot-removal work is in progress. ===> deadlock > > Regards, > Kenji Kaneshige > > > >> -----Original Message----- >> From: Yijing Wang [mailto:wangyijing@huawei.com] >> Sent: Wednesday, October 31, 2012 4:11 PM >> To: Bjorn Helgaas; Yinghai Lu; Kaneshige, Kenji/?? ??; Rafael; Rusty >> Russell; Mauro Carvalho Chehab; Oliver Neukum >> Cc: linux-pci@vger.kernel.org; Hanjun Guo; jiang.liu@huawei.com; Yijing >> Wang >> Subject: [RFC][PATCH] 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, eg.PLX8696). 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@huawei.com> >> --- >> 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 | 14 ++++++++++++-- >> 4 files changed, 19 insertions(+), 16 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@compaq.com>, Greg >> Kroah-Hartman <greg@kroah.com>, Dely Sy <dely.l.sy@intel.com>" >> @@ -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..8e5e571 100644 >> --- a/drivers/pci/hotplug/pciehp_hpc.c >> +++ b/drivers/pci/hotplug/pciehp_hpc.c >> @@ -773,23 +773,33 @@ 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), "pciehpd_%s", >> + pci_name(ctrl->pcie->port)); >> + 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 -1; >> } >> >> static void pcie_cleanup_slot(struct controller *ctrl) >> { >> struct slot *slot = ctrl->slot; >> cancel_delayed_work(&slot->work); >> - flush_workqueue(pciehp_wq); >> + flush_workqueue(slot->wq); >> + destroy_workqueue(slot->wq); >> kfree(slot); >> } >> >> -- >> 1.7.1 >> > > > . >
Hi Yijing, I have some comments. Sorry for the delay. <snip.> > --- a/drivers/pci/hotplug/pciehp_hpc.c > +++ b/drivers/pci/hotplug/pciehp_hpc.c > @@ -773,23 +773,33 @@ 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), "pciehpd_%s", > + pci_name(ctrl->pcie->port)); The name of the threads seems to be cut off. $ ps aux | grep pciehp root 125 0.0 0.0 0 0 ? S< 18:54 0:00 [pciehpd_0000:00] root 126 0.0 0.0 0 0 ? S< 18:54 0:00 [pciehpd_0000:00] root 127 0.0 0.0 0 0 ? S< 18:54 0:00 [pciehpd_0000:0b] root 128 0.0 0.0 0 0 ? S< 18:54 0:00 [pciehpd_0000:0b] root 129 0.0 0.0 0 0 ? S< 18:54 0:00 [pciehpd_0000:0b] root 130 0.0 0.0 0 0 ? S< 18:54 0:00 [pciehpd_0000:0b] root 131 0.0 0.0 0 0 ? S< 18:55 0:00 [pciehpd_0000:1a] root 132 0.0 0.0 0 0 ? S< 18:55 0:00 [pciehpd_0000:1a] root 133 0.0 0.0 0 0 ? S< 18:55 0:00 [pciehpd_0000:1a] root 134 0.0 0.0 0 0 ? S< 18:55 0:00 [pciehpd_0000:1a] How about using slot name for the thread name? <snip.> > > static void pcie_cleanup_slot(struct controller *ctrl) > { > struct slot *slot = ctrl->slot; > cancel_delayed_work(&slot->work); > - flush_workqueue(pciehp_wq); > + flush_workqueue(slot->wq); > + destroy_workqueue(slot->wq); > kfree(slot); > } I think flush_workqueue() call is no longer required because it is done in destroy_workqueue() code path. Regards, Kenji Kaneshige -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 2012/11/7 18:47, Kaneshige, Kenji wrote: > Hi Yijing, > > I have some comments. Sorry for the delay. > > <snip.> > Hi Kaneshige, Thanks for your review and comments very much! I will update this patch and using slot name instead of device name, it's really a good suggestion. Also I will remove the redundant flush_workqueue(). Thanks! Yijing. >> --- a/drivers/pci/hotplug/pciehp_hpc.c >> +++ b/drivers/pci/hotplug/pciehp_hpc.c >> @@ -773,23 +773,33 @@ 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), "pciehpd_%s", >> + pci_name(ctrl->pcie->port)); > > The name of the threads seems to be cut off. > > $ ps aux | grep pciehp > root 125 0.0 0.0 0 0 ? S< 18:54 0:00 [pciehpd_0000:00] > root 126 0.0 0.0 0 0 ? S< 18:54 0:00 [pciehpd_0000:00] > root 127 0.0 0.0 0 0 ? S< 18:54 0:00 [pciehpd_0000:0b] > root 128 0.0 0.0 0 0 ? S< 18:54 0:00 [pciehpd_0000:0b] > root 129 0.0 0.0 0 0 ? S< 18:54 0:00 [pciehpd_0000:0b] > root 130 0.0 0.0 0 0 ? S< 18:54 0:00 [pciehpd_0000:0b] > root 131 0.0 0.0 0 0 ? S< 18:55 0:00 [pciehpd_0000:1a] > root 132 0.0 0.0 0 0 ? S< 18:55 0:00 [pciehpd_0000:1a] > root 133 0.0 0.0 0 0 ? S< 18:55 0:00 [pciehpd_0000:1a] > root 134 0.0 0.0 0 0 ? S< 18:55 0:00 [pciehpd_0000:1a] > > How about using slot name for the thread name? > > <snip.> > >> >> static void pcie_cleanup_slot(struct controller *ctrl) >> { >> struct slot *slot = ctrl->slot; >> cancel_delayed_work(&slot->work); >> - flush_workqueue(pciehp_wq); >> + flush_workqueue(slot->wq); >> + destroy_workqueue(slot->wq); >> kfree(slot); >> } > > I think flush_workqueue() call is no longer required because > it is done in destroy_workqueue() code path. > > Regards, > Kenji Kaneshige > > > . >
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@compaq.com>, Greg Kroah-Hartman <greg@kroah.com>, Dely Sy <dely.l.sy@intel.com>" @@ -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..8e5e571 100644 --- a/drivers/pci/hotplug/pciehp_hpc.c +++ b/drivers/pci/hotplug/pciehp_hpc.c @@ -773,23 +773,33 @@ 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), "pciehpd_%s", + pci_name(ctrl->pcie->port)); + 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 -1; } static void pcie_cleanup_slot(struct controller *ctrl) { struct slot *slot = ctrl->slot; cancel_delayed_work(&slot->work); - flush_workqueue(pciehp_wq); + flush_workqueue(slot->wq); + destroy_workqueue(slot->wq); kfree(slot); }
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, eg.PLX8696). 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@huawei.com> --- 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 | 14 ++++++++++++-- 4 files changed, 19 insertions(+), 16 deletions(-)