Staging: hv: util: Invoke cn_netlink_send() in a work context
Invoke cn_netlink_send() in a work context as opposed being called
in the context of channel callback. On entry into the channel callback
code the channel inbound spin lock is held and deferring to a work
context avoids having to invoke cn_netlink_send() while holding
the inbound lock. As part of this adjustment, also increase the
timeout value for waiting for the user level component of KVP.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/staging/hv/hv_kvp.c b/drivers/staging/hv/hv_kvp.c
index 307aedc..1e9515c 100644
--- a/drivers/staging/hv/hv_kvp.c
+++ b/drivers/staging/hv/hv_kvp.c
@@ -44,11 +44,12 @@
static struct {
bool active; /* transaction status - active or not */
int recv_len; /* number of bytes received. */
+ int index; /* current index */
struct vmbus_channel *recv_channel; /* chn we got the request */
u64 recv_req_id; /* request ID. */
} kvp_transaction;
-static int kvp_send_key(int index);
+static void kvp_send_key(struct work_struct *dummy);
#define TIMEOUT_FIRED 1
@@ -57,6 +58,7 @@
static void kvp_register(void);
static DECLARE_DELAYED_WORK(kvp_work, kvp_work_func);
+static DECLARE_WORK(kvp_sendkey_work, kvp_send_key);
static struct cb_id kvp_id = { CN_KVP_IDX, CN_KVP_VAL };
static const char kvp_name[] = "kvp_kernel_module";
@@ -121,10 +123,11 @@
}
}
-static int
-kvp_send_key(int index)
+static void
+kvp_send_key(struct work_struct *dummy)
{
struct cn_msg *msg;
+ int index = kvp_transaction.index;
msg = kzalloc(sizeof(*msg) + sizeof(struct hv_kvp_msg) , GFP_ATOMIC);
@@ -136,9 +139,8 @@
msg->len = sizeof(struct hv_ku_msg);
cn_netlink_send(msg, 0, GFP_ATOMIC);
kfree(msg);
- return 0;
}
- return 1;
+ return;
}
/*
@@ -286,6 +288,7 @@
kvp_transaction.recv_channel = channel;
kvp_transaction.recv_req_id = requestid;
kvp_transaction.active = true;
+ kvp_transaction.index = kvp_data->index;
/*
* Get the information from the
@@ -296,8 +299,8 @@
* Set a timeout to deal with
* user-mode not responding.
*/
- kvp_send_key(kvp_data->index);
- schedule_delayed_work(&kvp_work, 100);
+ schedule_work(&kvp_sendkey_work);
+ schedule_delayed_work(&kvp_work, 5*HZ);
return;
@@ -332,4 +335,5 @@
{
cn_del_callback(&kvp_id);
cancel_delayed_work_sync(&kvp_work);
+ cancel_work_sync(&kvp_sendkey_work);
}