Branden Bonaby <brandonbonab...@gmail.com> writes:
> Expose the test parameters as part of the sysfs channel attributes.
> We will control the testing state via these attributes.
>
> Signed-off-by: Branden Bonaby <brandonbonab...@gmail.com>
> ---
> Documentation/ABI/stable/sysfs-bus-vmbus | 22 ++++++
> drivers/hv/vmbus_drv.c | 97 +++++++++++++++++++++++-
> 2 files changed, 118 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/ABI/stable/sysfs-bus-vmbus
> b/Documentation/ABI/stable/sysfs-bus-vmbus
> index 8e8d167eca31..239fcb6fdc75 100644
> --- a/Documentation/ABI/stable/sysfs-bus-vmbus
> +++ b/Documentation/ABI/stable/sysfs-bus-vmbus
> @@ -185,3 +185,25 @@ Contact: Michael Kelley <mikel...@microsoft.com>
> Description: Total number of write operations that encountered an outbound
> ring buffer full condition
> Users: Debugging tools
> +
> +What: /sys/bus/vmbus/devices/<UUID>/fuzz_test_state
I would prefer this to go under /sys/kernel/debug/ as this is clearly a
debug/test feature.
> +Date: July 2019
> +KernelVersion: 5.2
> +Contact: Branden Bonaby <brandonbonab...@gmail.com>
> +Description: Fuzz testing status of a vmbus device, whether its in an ON
> + state or a OFF state
> +Users: Debugging tools
> +
> +What: /sys/bus/vmbus/devices/<UUID>/fuzz_test_buffer_delay
> +Date: July 2019
> +KernelVersion: 5.2
> +Contact: Branden Bonaby <brandonbonab...@gmail.com>
> +Description: Fuzz testing buffer delay value between 0 - 1000
> +Users: Debugging tools
> +
> +What: /sys/bus/vmbus/devices/<UUID>/fuzz_test_message_delay
> +Date: July 2019
> +KernelVersion: 5.2
> +Contact: Branden Bonaby <brandonbonab...@gmail.com>
> +Description: Fuzz testing message delay value between 0 - 1000
> +Users: Debugging tools
> diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
> index 92b1874b3eb3..0c71fd66ef81 100644
> --- a/drivers/hv/vmbus_drv.c
> +++ b/drivers/hv/vmbus_drv.c
> @@ -22,7 +22,7 @@
> #include <linux/clockchips.h>
> #include <linux/cpu.h>
> #include <linux/sched/task_stack.h>
> -
> +#include <linux/kernel.h>
> #include <asm/mshyperv.h>
> #include <linux/notifier.h>
> #include <linux/ptrace.h>
> @@ -584,6 +584,98 @@ static ssize_t driver_override_show(struct device *dev,
> }
> static DEVICE_ATTR_RW(driver_override);
>
> +static ssize_t fuzz_test_state_store(struct device *dev,
> + struct device_attribute *attr,
> + const char *buf, size_t count)
> +{
> + struct hv_device *hv_dev = device_to_hv_device(dev);
> + struct vmbus_channel *channel = hv_dev->channel;
> + int state;
> + int delay = kstrtoint(buf, 0, &state);
> +
> + if (delay)
> + return count;
> + if (state)
> + channel->fuzz_testing_state = 1;
> + else
> + channel->fuzz_testing_state = 0;
> + return count;
> +}
> +
> +static ssize_t fuzz_test_state_show(struct device *dev,
> + struct device_attribute *dev_attr,
> + char *buf)
> +{
> + struct hv_device *hv_dev = device_to_hv_device(dev);
> + struct vmbus_channel *channel = hv_dev->channel;
> +
> + return sprintf(buf, "%u\n", channel->fuzz_testing_state);
> +}
> +static DEVICE_ATTR_RW(fuzz_test_state);
> +
> +static ssize_t fuzz_test_buffer_delay_store(struct device *dev,
> + struct device_attribute *attr,
> + const char *buf, size_t count)
> +{
> + struct hv_device *hv_dev = device_to_hv_device(dev);
> + struct vmbus_channel *channel = hv_dev->channel;
> + int val;
> + int delay = kstrtoint(buf, 0, &val);
> +
> + if (delay)
> + return count;
> + if (val >= 1 && val <= 1000)
> + channel->fuzz_testing_buffer_delay = val;
> + /*Best to not use else statement here since we want
> + *the buffer delay to remain the same if val > 1000
> + */
> + else if (val <= 0)
> + channel->fuzz_testing_buffer_delay = 0;
> + return count;
> +}
> +
> +static ssize_t fuzz_test_buffer_delay_show(struct device *dev,
> + struct device_attribute *dev_attr,
> + char *buf)
> +{
> + struct hv_device *hv_dev = device_to_hv_device(dev);
> + struct vmbus_channel *channel = hv_dev->channel;
> +
> + return sprintf(buf, "%u\n", channel->fuzz_testing_buffer_delay);
> +}
> +static DEVICE_ATTR_RW(fuzz_test_buffer_delay);
> +
> +static ssize_t fuzz_test_message_delay_store(struct device *dev,
> + struct device_attribute *attr,
> + const char *buf, size_t count)
> +{
> + struct hv_device *hv_dev = device_to_hv_device(dev);
> + struct vmbus_channel *channel = hv_dev->channel;
> + int val;
> + int delay = kstrtoint(buf, 0, &val);
> +
> + if (delay)
> + return count;
> + if (val >= 1 && val <= 1000)
> + channel->fuzz_testing_message_delay = val;
> + /*Best to not use else statement here since we want
> + *the message delay to remain the same if val > 1000
> + */
> + else if (val <= 0)
> + channel->fuzz_testing_message_delay = 0;
> + return count;
> +}
> +
> +static ssize_t fuzz_test_message_delay_show(struct device *dev,
> + struct device_attribute *dev_attr,
> + char *buf)
> +{
> + struct hv_device *hv_dev = device_to_hv_device(dev);
> + struct vmbus_channel *channel = hv_dev->channel;
> +
> + return sprintf(buf, "%u\n", channel->fuzz_testing_message_delay);
> +}
> +static DEVICE_ATTR_RW(fuzz_test_message_delay);
> /* Set up per device attributes in /sys/bus/vmbus/devices/<bus device> */
> static struct attribute *vmbus_dev_attrs[] = {
> &dev_attr_id.attr,
> @@ -615,6 +707,9 @@ static struct attribute *vmbus_dev_attrs[] = {
> &dev_attr_vendor.attr,
> &dev_attr_device.attr,
> &dev_attr_driver_override.attr,
> + &dev_attr_fuzz_test_state.attr,
> + &dev_attr_fuzz_test_buffer_delay.attr,
> + &dev_attr_fuzz_test_message_delay.attr,
> NULL,
> };
--
Vitaly
