diff options
author | Vitaly Kuznetsov <vkuznets@redhat.com> | 2015-02-27 11:25:57 -0800 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-03-01 19:30:07 -0800 |
commit | e086748c655ab99bac91b87d1bb59d9cc45867b9 (patch) | |
tree | 004fda805ee1c6124bcd275357ccafed6c786ad5 | |
parent | 32a158325acf12842764b1681f53903673f2f22e (diff) | |
download | linux-e086748c655ab99bac91b87d1bb59d9cc45867b9.tar.bz2 |
Drivers: hv: vmbus: Teardown clockevent devices on module unload
Newly introduced clockevent devices made it impossible to unload hv_vmbus
module as clockevents_config_and_register() takes additional reverence to
the module. To make it possible again we do the following:
- avoid setting dev->owner for clockevent devices;
- implement hv_synic_clockevents_cleanup() doing clockevents_unbind_device();
- call it from vmbus_exit().
In theory hv_synic_clockevents_cleanup() can be merged with hv_synic_cleanup(),
however, we call hv_synic_cleanup() from smp_call_function_single() and this
doesn't work for clockevents_unbind_device() as it does such call on its own. I
opted for a separate function.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/hv/hv.c | 25 | ||||
-rw-r--r-- | drivers/hv/hyperv_vmbus.h | 2 | ||||
-rw-r--r-- | drivers/hv/vmbus_drv.c | 1 |
3 files changed, 27 insertions, 1 deletions
diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c index 39531dcf582f..d3943bceecc3 100644 --- a/drivers/hv/hv.c +++ b/drivers/hv/hv.c @@ -312,7 +312,11 @@ static void hv_init_clockevent_device(struct clock_event_device *dev, int cpu) dev->features = CLOCK_EVT_FEAT_ONESHOT; dev->cpumask = cpumask_of(cpu); dev->rating = 1000; - dev->owner = THIS_MODULE; + /* + * Avoid settint dev->owner = THIS_MODULE deliberately as doing so will + * result in clockevents_config_and_register() taking additional + * references to the hv_vmbus module making it impossible to unload. + */ dev->set_mode = hv_ce_setmode; dev->set_next_event = hv_ce_set_next_event; @@ -470,6 +474,20 @@ void hv_synic_init(void *arg) } /* + * hv_synic_clockevents_cleanup - Cleanup clockevent devices + */ +void hv_synic_clockevents_cleanup(void) +{ + int cpu; + + if (!(ms_hyperv.features & HV_X64_MSR_SYNTIMER_AVAILABLE)) + return; + + for_each_online_cpu(cpu) + clockevents_unbind_device(hv_context.clk_evt[cpu], cpu); +} + +/* * hv_synic_cleanup - Cleanup routine for hv_synic_init(). */ void hv_synic_cleanup(void *arg) @@ -483,6 +501,11 @@ void hv_synic_cleanup(void *arg) if (!hv_context.synic_initialized) return; + /* Turn off clockevent device */ + if (ms_hyperv.features & HV_X64_MSR_SYNTIMER_AVAILABLE) + hv_ce_setmode(CLOCK_EVT_MODE_SHUTDOWN, + hv_context.clk_evt[cpu]); + rdmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64); shared_sint.masked = 1; diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h index 6cf2de9f487a..b055e53bbc6e 100644 --- a/drivers/hv/hyperv_vmbus.h +++ b/drivers/hv/hyperv_vmbus.h @@ -572,6 +572,8 @@ extern void hv_synic_init(void *irqarg); extern void hv_synic_cleanup(void *arg); +extern void hv_synic_clockevents_cleanup(void); + /* * Host version information. */ diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index d8233d4513a5..6d99aa5c49d6 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -1032,6 +1032,7 @@ static void __exit vmbus_exit(void) int cpu; vmbus_connection.conn_state = DISCONNECTED; + hv_synic_clockevents_cleanup(); hv_remove_vmbus_irq(); vmbus_free_channels(); bus_unregister(&hv_bus); |