On Thu, 23 Aug 2018 11:09:56 +0300
Claudiu Beznea [off-list ref] wrote:

On 14.08.2018 09:50, Ajay Singh wrote:

quoted

Avoid use of static variable 'clients_count' and move it part of 'wilc'
structure.

Signed-off-by: Ajay Singh <ajay.kathat@microchip.com>
---
 drivers/staging/wilc1000/host_interface.c     | 9 ++++-----
 drivers/staging/wilc1000/wilc_wfi_netdevice.h | 1 +
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/staging/wilc1000/host_interface.c b/drivers/staging/wilc1000/host_interface.c
index 6225e67..d930f06 100644
--- a/drivers/staging/wilc1000/host_interface.c
+++ b/drivers/staging/wilc1000/host_interface.c

@@ -199,7 +199,6 @@ static u8 rcv_assoc_resp[MAX_ASSOC_RESP_FRAME_SIZE];
 
 static u8 set_ip[2][4];
 static u8 get_ip[2][4];
-static u32 clients_count;
 
 static int host_int_get_ipaddress(struct wilc_vif *vif, u8 *ip_addr, u8 idx);
 

@@ -3456,7 +3455,7 @@ int wilc_init(struct net_device *dev, struct host_if_drv **hif_drv_handler)
 
 	vif->obtaining_ip = false;
 
-	if (clients_count == 0) {
+	if (wilc->clients_count == 0) {

The check of this should be mutex protected or a hif init/deinit should be
done in probe/remove code not not in open (I'm for the second approach).
Imagine this scenario:

vif 1: is down
vif 2: is down. "ifconfig vif2 up" is executed and the execution reach this
       point and then suspends after "if (wilc->clients_count == 0)" check
vif 1: "ifconfig vif1 up" and execution reach the end of this function and
       then the execution for vif 2 resumes. This will init twice the hif
       mutex, completion etc.

quoted

 		init_completion(&hif_driver_comp);
 		mutex_init(&hif_deinit_lock);
 

Instead of using mutex protection, it would be better to move this block to
wilc_netdev_init() where wilc structure is initialized 

quoted

@@ -3490,7 +3489,7 @@ int wilc_init(struct net_device *dev, struct host_if_drv **hif_drv_handler)
 
 	mutex_unlock(&hif_drv->cfg_values_lock);
 
-	clients_count++;
+	wilc->clients_count++;
 
 	return 0;
 }

@@ -3526,7 +3525,7 @@ int wilc_deinit(struct wilc_vif *vif)
 
 	hif_drv->hif_state = HOST_IF_IDLE;
 
-	if (clients_count == 1)	{
+	if (vif->wilc->clients_count == 1) {
 		struct host_if_msg *msg;
 
 		msg = wilc_alloc_work(vif, handle_hif_exit_work, true);

@@ -3544,7 +3543,7 @@ int wilc_deinit(struct wilc_vif *vif)
 
 	kfree(hif_drv);
 
-	clients_count--;
+	vif->wilc->clients_count--;
 	terminated_handle = NULL;
 	mutex_unlock(&hif_deinit_lock);
 	return result;

diff --git a/drivers/staging/wilc1000/wilc_wfi_netdevice.h b/drivers/staging/wilc1000/wilc_wfi_netdevice.h
index 8e56a28..8cccbbc 100644
--- a/drivers/staging/wilc1000/wilc_wfi_netdevice.h
+++ b/drivers/staging/wilc1000/wilc_wfi_netdevice.h

@@ -171,6 +171,7 @@ struct wilc {
 
 	struct rf_info dummy_statistics;
 	bool enable_ps;
+	int clients_count;
 };
 
 struct wilc_wfi_mon_priv {