[PATCH V3 06/14] Drivers: hv: vss: Improve log messages.

From: kys
Date: Sun Nov 06 2016 - 14:22:37 EST


From: Alex Ng <alexng@xxxxxxxxxxxxxxxxxxxxxx>

Adding log messages to help troubleshoot error cases and transaction
handling.

Signed-off-by: Alex Ng <alexng@xxxxxxxxxxxxx>
Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx>
---
drivers/hv/hv_snapshot.c | 25 +++++++++++++++++++------
1 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/drivers/hv/hv_snapshot.c b/drivers/hv/hv_snapshot.c
index a670713..5c95ba1 100644
--- a/drivers/hv/hv_snapshot.c
+++ b/drivers/hv/hv_snapshot.c
@@ -120,7 +120,7 @@ static int vss_handle_handshake(struct hv_vss_msg *vss_msg)
default:
return -EINVAL;
}
- pr_debug("VSS: userspace daemon ver. %d connected\n", dm_reg_value);
+ pr_info("VSS: userspace daemon ver. %d connected\n", dm_reg_value);
return 0;
}

@@ -128,8 +128,10 @@ static int vss_on_msg(void *msg, int len)
{
struct hv_vss_msg *vss_msg = (struct hv_vss_msg *)msg;

- if (len != sizeof(*vss_msg))
+ if (len != sizeof(*vss_msg)) {
+ pr_debug("VSS: Message size does not match length\n");
return -EINVAL;
+ }

if (vss_msg->vss_hdr.operation == VSS_OP_REGISTER ||
vss_msg->vss_hdr.operation == VSS_OP_REGISTER1) {
@@ -137,8 +139,11 @@ static int vss_on_msg(void *msg, int len)
* Don't process registration messages if we're in the middle
* of a transaction processing.
*/
- if (vss_transaction.state > HVUTIL_READY)
+ if (vss_transaction.state > HVUTIL_READY) {
+ pr_debug("VSS: Got unexpected registration request\n");
return -EINVAL;
+ }
+
return vss_handle_handshake(vss_msg);
} else if (vss_transaction.state == HVUTIL_USERSPACE_REQ) {
vss_transaction.state = HVUTIL_USERSPACE_RECV;
@@ -155,7 +160,7 @@ static int vss_on_msg(void *msg, int len)
}
} else {
/* This is a spurious call! */
- pr_warn("VSS: Transaction not active\n");
+ pr_debug("VSS: Transaction not active\n");
return -EINVAL;
}
return 0;
@@ -168,8 +173,10 @@ static void vss_send_op(void)
struct hv_vss_msg *vss_msg;

/* The transaction state is wrong. */
- if (vss_transaction.state != HVUTIL_HOSTMSG_RECEIVED)
+ if (vss_transaction.state != HVUTIL_HOSTMSG_RECEIVED) {
+ pr_debug("VSS: Unexpected attempt to send to daemon\n");
return;
+ }

vss_msg = kzalloc(sizeof(*vss_msg), GFP_KERNEL);
if (!vss_msg)
@@ -210,9 +217,13 @@ static void vss_handle_request(struct work_struct *dummy)
case VSS_OP_HOT_BACKUP:
if (vss_transaction.state < HVUTIL_READY) {
/* Userspace is not registered yet */
+ pr_debug("VSS: Not ready for request.\n");
vss_respond_to_host(HV_E_FAIL);
return;
}
+
+ pr_debug("VSS: Received request for op code: %d\n",
+ vss_transaction.msg->vss_hdr.operation);
vss_transaction.state = HVUTIL_HOSTMSG_RECEIVED;
vss_send_op();
return;
@@ -353,8 +364,10 @@ static void vss_on_reset(void)

hvt = hvutil_transport_init(vss_devname, CN_VSS_IDX, CN_VSS_VAL,
vss_on_msg, vss_on_reset);
- if (!hvt)
+ if (!hvt) {
+ pr_warn("VSS: Failed to initialize transport\n");
return -EFAULT;
+ }

return 0;
}
--
1.7.4.1