On Thursday, November 01, 2012 01:17:58 PM Toshi Kani wrote: > On Thu, 2012-11-01 at 11:28 -0700, Yinghai Lu wrote: > > On Thu, Nov 1, 2012 at 9:43 AM, Toshi Kani <toshi.kani@xxxxxx> wrote: > > > > > > Rafael pointed out in my CPU hot-remove patch that > > > acpi_bus_hot_remove_device() was not exported for modules. Looks like > > > you have the same problem here. FYI, I just sent the following patch > > > that exports acpi_bus_hot_remove_device() and acpi_os_hotplug_execute(). > > > > > > https://lkml.org/lkml/2012/11/1/225 > > > > acpi_os_hotplug_execute() does not like having good quality yet. > > > > c02256be (Zhang Rui 2009-06-23 10:20:29 +0800 941) /* > > c02256be (Zhang Rui 2009-06-23 10:20:29 +0800 942) * We > > can't run hotplug code in keventd_wq/kacpid_wq/kacpid_notify_wq > > c02256be (Zhang Rui 2009-06-23 10:20:29 +0800 943) * > > because the hotplug code may call driver .remove() functions, > > c02256be (Zhang Rui 2009-06-23 10:20:29 +0800 944) * > > which invoke flush_scheduled_work/acpi_os_wait_events_complete > > c02256be (Zhang Rui 2009-06-23 10:20:29 +0800 945) * to > > flush these workqueues. > > c02256be (Zhang Rui 2009-06-23 10:20:29 +0800 946) */ > > c02256be (Zhang Rui 2009-06-23 10:20:29 +0800 947) queue > > = hp ? kacpi_hotplug_wq : > > c02256be (Zhang Rui 2009-06-23 10:20:29 +0800 948) > > (type == OSL_NOTIFY_HANDLER ? kacpi_notify_wq : kacpid_wq); > > 9ac61856 (Bjorn Helgaas 2009-08-31 22:32:10 +0000 949) > > dpc->wait = hp ? 1 : 0; > > bc73675b (Zhang Rui 2010-03-22 15:48:54 +0800 950) > > bc73675b (Zhang Rui 2010-03-22 15:48:54 +0800 951) if > > (queue == kacpi_hotplug_wq) > > bc73675b (Zhang Rui 2010-03-22 15:48:54 +0800 952) > > INIT_WORK(&dpc->work, acpi_os_execute_deferred); > > bc73675b (Zhang Rui 2010-03-22 15:48:54 +0800 953) else > > if (queue == kacpi_notify_wq) > > bc73675b (Zhang Rui 2010-03-22 15:48:54 +0800 954) > > INIT_WORK(&dpc->work, acpi_os_execute_deferred); > > bc73675b (Zhang Rui 2010-03-22 15:48:54 +0800 955) else > > bc73675b (Zhang Rui 2010-03-22 15:48:54 +0800 956) > > INIT_WORK(&dpc->work, acpi_os_execute_deferred); > > bc73675b (Zhang Rui 2010-03-22 15:48:54 +0800 957) > > > > really don't know why checking queue and call same code in every branch. > > > > from comm: > > > > commit bc73675b99fd9850dd914be01d71af99c5d2a1ae > > Author: Zhang Rui <rui.zhang@xxxxxxxxx> > > Date: Mon Mar 22 15:48:54 2010 +0800 > > > > ACPI: fixes a false alarm from lockdep > > > > fixes a false alarm from lockdep, as acpi hotplug workqueue waits other > > workqueues. > > http://bugzilla.kernel.org/show_bug.cgi?id=14553 > > https://bugzilla.kernel.org/show_bug.cgi?id=15521 > > > > Original-patch-from: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > > Signed-off-by: Shaohua Li <shaohua.li@xxxxxxxxx> > > Signed-off-by: Zhang Rui <rui.zhang@xxxxxxxxx> > > Signed-off-by: Len Brown <len.brown@xxxxxxxxx> > > > > diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c > > index 8e6d866..900da68 100644 > > --- a/drivers/acpi/osl.c > > +++ b/drivers/acpi/osl.c > > @@ -758,7 +758,14 @@ static acpi_status > > __acpi_os_execute(acpi_execute_type type, > > queue = hp ? kacpi_hotplug_wq : > > (type == OSL_NOTIFY_HANDLER ? kacpi_notify_wq : kacpid_wq); > > dpc->wait = hp ? 1 : 0; > > - INIT_WORK(&dpc->work, acpi_os_execute_deferred); > > + > > + if (queue == kacpi_hotplug_wq) > > + INIT_WORK(&dpc->work, acpi_os_execute_deferred); > > + else if (queue == kacpi_notify_wq) > > + INIT_WORK(&dpc->work, acpi_os_execute_deferred); > > + else > > + INIT_WORK(&dpc->work, acpi_os_execute_deferred); > > + > > ret = queue_work(queue, &dpc->work); > > > > if (!ret) { > > > > > > Len or Rafael, > > can you just revert that silly patch? > > Hi Yinghai, > > Per the following thread, the code seems to be written in this way to > allocate a separate lock_class_key for each work queue. It should have > had some comment to explain this, though. > > https://lkml.org/lkml/2009/12/13/304 The code has evolved since then, however, so that it doesn't make sense any more. Thanks, Rafael -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
