Hi Tang,
2012/10/24 15:05, Tang Chen wrote:
> As the comments in __acpi_os_execute() said:
>
> We can't run hotplug code in keventd_wq/kacpid_wq/kacpid_notify_wq
> because the hotplug code may call driver .remove() functions,
> which invoke flush_scheduled_work/acpi_os_wait_events_complete
> to flush these workqueues.
>
> we should keep the hotplug code in kacpi_hotplug_wq.
>
> But we have the following call series in kernel now:
> acpi_ev_queue_notify_request()
> |--> acpi_os_execute()
> |--> __acpi_os_execute(type, function, context, 0)
>
> The last parameter 0 makes the container_notify_cb() executed in
> kacpi_notify_wq or kacpid_wq. So, we need to put the real hotplug code
> into kacpi_hotplug_wq.
I cannot understand the purpose of the patch.
Is the patch a bug fix patch? If yes, what problem happens?
Thanks,
Yasuaki Ishimatsu
>
> Signed-off-by: Tang Chen <tangc...@cn.fujitsu.com>
> ---
> drivers/acpi/container.c | 17 ++++++++++++++++-
> 1 files changed, 16 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/acpi/container.c b/drivers/acpi/container.c
> index 69e2d6b..d300e03 100644
> --- a/drivers/acpi/container.c
> +++ b/drivers/acpi/container.c
> @@ -35,6 +35,7 @@
> #include <acpi/acpi_bus.h>
> #include <acpi/acpi_drivers.h>
> #include <acpi/container.h>
> +#include <acpi/acpiosxf.h>
>
> #define PREFIX "ACPI: "
>
> @@ -165,14 +166,21 @@ static int container_device_add(struct acpi_device
> **device, acpi_handle handle)
> return result;
> }
>
> -static void container_notify_cb(acpi_handle handle, u32 type, void *context)
> +static void __container_notify_cb(struct work_struct *work)
> {
> struct acpi_device *device = NULL;
> int result;
> int present;
> acpi_status status;
> + struct acpi_hp_work *hp_work;
> + acpi_handle handle;
> + u32 type;
> u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; /* default */
>
> + hp_work = container_of(work, struct acpi_hp_work, work);
> + handle = hp_work->handle;
> + type = hp_work->type;
> +
> switch (type) {
> case ACPI_NOTIFY_BUS_CHECK:
> /* Fall through */
> @@ -224,6 +232,13 @@ static void container_notify_cb(acpi_handle handle, u32
> type, void *context)
> return;
> }
>
> +static void container_notify_cb(acpi_handle handle, u32 type,
> + void *context)
> +{
> + alloc_acpi_hp_work(handle, type, context,
> + __container_notify_cb);
> +}
> +
> static acpi_status
> container_walk_namespace_cb(acpi_handle handle,
> u32 lvl, void *context, void **rv)
>
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