Introduce user specified latency in the packet reception path.
Signed-off-by: Branden Bonaby <brandonbonaby94@xxxxxxxxx>
---
Changes in v2:
- Add #ifdef in Kconfig file so test code will not interfere
with non-test code.
- Move test code functions for delay to hyperv_vmbus header
file.
- Wrap test code under #ifdef statement.
drivers/hv/Kconfig | 7 +++++++
drivers/hv/connection.c | 3 +++
drivers/hv/hyperv_vmbus.h | 20 ++++++++++++++++++++
drivers/hv/ring_buffer.c | 7 +++++++
include/linux/hyperv.h | 21 +++++++++++++++++++++
5 files changed, 58 insertions(+)
diff --git a/drivers/hv/Kconfig b/drivers/hv/Kconfig
index 9a59957922d4..d97437ba0626 100644
--- a/drivers/hv/Kconfig
+++ b/drivers/hv/Kconfig
@@ -29,4 +29,11 @@ config HYPERV_BALLOON
help
Select this option to enable Hyper-V Balloon driver.
+config HYPERV_TESTING
+ bool "Hyper-V testing"
+ default n
+ depends on HYPERV && DEBUG_FS
+ help
+ Select this option to enable Hyper-V vmbus testing.
+
endmenu
diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
index 09829e15d4a0..c9c63a4033cd 100644
--- a/drivers/hv/connection.c
+++ b/drivers/hv/connection.c
@@ -357,6 +357,9 @@ void vmbus_on_event(unsigned long data)
trace_vmbus_on_event(channel);
+#ifdef CONFIG_HYPERV_TESTING
+ hv_debug_delay_test(channel, INTERRUPT_DELAY);
+#endif /* CONFIG_HYPERV_TESTING */
do {
void (*callback_fn)(void *);
diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h
index 362e70e9d145..edf14f596d8c 100644
--- a/drivers/hv/hyperv_vmbus.h
+++ b/drivers/hv/hyperv_vmbus.h
@@ -357,4 +357,24 @@ enum hvutil_device_state {
HVUTIL_DEVICE_DYING, /* driver unload is in progress */
};
+#ifdef CONFIG_HYPERV_TESTING
+#include <linux/debugfs.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#define TESTING "hyperv"
+
+enum delay {
+ INTERRUPT_DELAY = 0,
+ MESSAGE_DELAY = 1,
+};
+
+int hv_debug_delay_files(struct hv_device *dev, struct dentry *root);
+int hv_debug_add_dev_dir(struct hv_device *dev);
+void hv_debug_rm_dev_dir(struct hv_device *dev);
+void hv_debug_rm_all_dir(void);
+void hv_debug_set_dir_dentry(struct hv_device *dev, struct dentry *root);
+void hv_debug_delay_test(struct vmbus_channel *channel, enum delay delay_type);
+
+#endif /* CONFIG_HYPERV_TESTING */
+
#endif /* _HYPERV_VMBUS_H */
diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c
index 9a03b163cbbd..51adda23b398 100644
--- a/drivers/hv/ring_buffer.c
+++ b/drivers/hv/ring_buffer.c
@@ -396,6 +396,10 @@ struct vmpacket_descriptor *hv_pkt_iter_first(struct vmbus_channel *channel)
struct hv_ring_buffer_info *rbi = &channel->inbound;
struct vmpacket_descriptor *desc;
+#ifdef CONFIG_HYPERV_TESTING
+ hv_debug_delay_test(channel, MESSAGE_DELAY);
+#endif /* CONFIG_HYPERV_TESTING */
+
if (hv_pkt_iter_avail(rbi) < sizeof(struct vmpacket_descriptor))
return NULL;
@@ -421,6 +425,9 @@ __hv_pkt_iter_next(struct vmbus_channel *channel,
u32 packetlen = desc->len8 << 3;
u32 dsize = rbi->ring_datasize;
+#ifdef CONFIG_HYPERV_TESTING
+ hv_debug_delay_test(channel, MESSAGE_DELAY);
+#endif /* CONFIG_HYPERV_TESTING */
/* bump offset to next potential packet */
rbi->priv_read_index += packetlen + VMBUS_PKT_TRAILER;
if (rbi->priv_read_index >= dsize)
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index 6256cc34c4a6..6bf8ef5c780c 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -926,6 +926,21 @@ struct vmbus_channel {
* full outbound ring buffer.
*/
u64 out_full_first;
+
+#ifdef CONFIG_HYPERV_TESTING
+ /* enabling/disabling fuzz testing on the channel (default is false)*/
+ bool fuzz_testing_state;
+
+ /* Interrupt delay will delay the guest from emptying the ring buffer
+ * for a specific amount of time. The delay is in microseconds and will
+ * be between 1 to a maximum of 1000, its default is 0 (no delay).
+ * The Message delay will delay guest reading on a per message basis
+ * in microseconds between 1 to 1000 with the default being 0
+ * (no delay).
+ */
+ u32 fuzz_testing_interrupt_delay;
+ u32 fuzz_testing_message_delay;
+#endif /* CONFIG_HYPERV_TESTING */
};
static inline bool is_hvsock_channel(const struct vmbus_channel *c)
@@ -1166,6 +1181,12 @@ struct hv_device {
struct vmbus_channel *channel;
struct kset *channels_kset;
+
+#ifdef CONFIG_HYPERV_TESTING
+ /* place holder to keep track of the dir for hv device in debugfs */
+ struct dentry *debug_dir;
+#endif /* CONFIG_HYPERV_TESTING */
+
};
--
2.17.1
