diff mbox series

wifi: wilc1000: Added back-off algorithm to balance tx queue packets.

Message ID 20230810184633.94338-1-prasurjya.rohansaikia@microchip.com
State Superseded
Headers show
Series wifi: wilc1000: Added back-off algorithm to balance tx queue packets. | expand

Commit Message

Prasurjya.Rohansaikia@microchip.com Aug. 10, 2023, 6:46 p.m. UTC 
From: Prasurjya Rohan Saikia <prasurjya.rohansaikia@microchip.com>

Added an algorithm to backoff the Tx Task when low memory scenario is
triggered at firmware. During high data transfer from host, the firmware
runs out of VMM memory, which is used to hold the frames from the host.
So added flow control to delay the transmit from host side when there is
not enough space to accomodate frames in firmware side.

Signed-off-by: Prasurjya Rohan Saikia <prasurjya.rohansaikia@microchip.com>
---
 .../net/wireless/microchip/wilc1000/netdev.c  | 19 ++++++++++++++++---
 .../net/wireless/microchip/wilc1000/netdev.h  |  2 ++
 2 files changed, 18 insertions(+), 3 deletions(-)

Comments

kernel test robot Aug. 12, 2023, 8:41 a.m. UTC | #1 
Hi,

kernel test robot noticed the following build warnings:

[auto build test WARNING on wireless-next/main]
[also build test WARNING on wireless/main linus/master v6.5-rc5 next-20230809]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Prasurjya-Rohansaikia-microchip-com/wifi-wilc1000-Added-back-off-algorithm-to-balance-tx-queue-packets/20230811-024902
base:   https://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless-next.git main
patch link:    https://lore.kernel.org/r/20230810184633.94338-1-prasurjya.rohansaikia%40microchip.com
patch subject: [PATCH] wifi: wilc1000: Added back-off algorithm to balance tx queue packets.
config: sh-allmodconfig (https://download.01.org/0day-ci/archive/20230812/202308121630.OJIJ2i9a-lkp@intel.com/config)
compiler: sh4-linux-gcc (GCC) 12.3.0
reproduce: (https://download.01.org/0day-ci/archive/20230812/202308121630.OJIJ2i9a-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202308121630.OJIJ2i9a-lkp@intel.com/

All warnings (new ones prefixed by >>):

   drivers/net/wireless/microchip/wilc1000/netdev.c: In function 'wilc_txq_task':
>> drivers/net/wireless/microchip/wilc1000/netdev.c:147:21: warning: variable 'timeout' set but not used [-Wunused-but-set-variable]
     147 |         signed long timeout;
         |                     ^~~~~~~


vim +/timeout +147 drivers/net/wireless/microchip/wilc1000/netdev.c

   142	
   143	static int wilc_txq_task(void *vp)
   144	{
   145		int ret;
   146		u32 txq_count;
 > 147		signed long timeout;
   148		struct wilc *wl = vp;
   149	
   150		complete(&wl->txq_thread_started);
   151		while (1) {
   152			if (wait_for_completion_interruptible(&wl->txq_event))
   153				continue;
   154			if (wl->close) {
   155				complete(&wl->txq_thread_started);
   156	
   157				while (!kthread_should_stop())
   158					schedule();
   159				break;
   160			}
   161			do {
   162				ret = wilc_wlan_handle_txq(wl, &txq_count);
   163				if (txq_count < FLOW_CONTROL_LOWER_THRESHOLD) {
   164					int srcu_idx;
   165					struct wilc_vif *ifc;
   166	
   167					srcu_idx = srcu_read_lock(&wl->srcu);
   168					list_for_each_entry_rcu(ifc, &wl->vif_list,
   169								list) {
   170						if (ifc->mac_opened &&
   171						    netif_queue_stopped(ifc->ndev))
   172							netif_wake_queue(ifc->ndev);
   173					}
   174					srcu_read_unlock(&wl->srcu, srcu_idx);
   175				}
   176				if (ret != WILC_VMM_ENTRY_FULL_RETRY)
   177					break;
   178				/* Back off from sending packets for some time.
   179				 * schedule_timeout will allow RX task to run and free
   180				 * buffers. Setting state to TASK_INTERRUPTIBLE will
   181				 * put the thread back to CPU running queue when it's
   182				 * signaled even if 'timeout' isn't elapsed. This gives
   183				 * faster chance for reserved SK buffers to be freed
   184				 */
   185				set_current_state(TASK_INTERRUPTIBLE);
   186				timeout = schedule_timeout(msecs_to_jiffies(TX_BACKOFF_WEIGHT_MS));
   187			} while (ret == WILC_VMM_ENTRY_FULL_RETRY && !wl->close);
   188		}
   189		return 0;
   190	}
   191
diff mbox series

Patch

diff --git a/drivers/net/wireless/microchip/wilc1000/netdev.c b/drivers/net/wireless/microchip/wilc1000/netdev.c
index e9f59de31b0b..40b34490f6ef 100644
--- a/drivers/net/wireless/microchip/wilc1000/netdev.c
+++ b/drivers/net/wireless/microchip/wilc1000/netdev.c
@@ -144,12 +144,13 @@  static int wilc_txq_task(void *vp)
 {
 	int ret;
 	u32 txq_count;
+	signed long timeout;
 	struct wilc *wl = vp;
 
 	complete(&wl->txq_thread_started);
 	while (1) {
-		wait_for_completion(&wl->txq_event);
-
+		if (wait_for_completion_interruptible(&wl->txq_event))
+			continue;
 		if (wl->close) {
 			complete(&wl->txq_thread_started);
 
@@ -166,11 +167,23 @@  static int wilc_txq_task(void *vp)
 				srcu_idx = srcu_read_lock(&wl->srcu);
 				list_for_each_entry_rcu(ifc, &wl->vif_list,
 							list) {
-					if (ifc->mac_opened && ifc->ndev)
+					if (ifc->mac_opened &&
+					    netif_queue_stopped(ifc->ndev))
 						netif_wake_queue(ifc->ndev);
 				}
 				srcu_read_unlock(&wl->srcu, srcu_idx);
 			}
+			if (ret != WILC_VMM_ENTRY_FULL_RETRY)
+				break;
+			/* Back off from sending packets for some time.
+			 * schedule_timeout will allow RX task to run and free
+			 * buffers. Setting state to TASK_INTERRUPTIBLE will
+			 * put the thread back to CPU running queue when it's
+			 * signaled even if 'timeout' isn't elapsed. This gives
+			 * faster chance for reserved SK buffers to be freed
+			 */
+			set_current_state(TASK_INTERRUPTIBLE);
+			timeout = schedule_timeout(msecs_to_jiffies(TX_BACKOFF_WEIGHT_MS));
 		} while (ret == WILC_VMM_ENTRY_FULL_RETRY && !wl->close);
 	}
 	return 0;
diff --git a/drivers/net/wireless/microchip/wilc1000/netdev.h b/drivers/net/wireless/microchip/wilc1000/netdev.h
index bb1a315a7b7e..380ad38ecb64 100644
--- a/drivers/net/wireless/microchip/wilc1000/netdev.h
+++ b/drivers/net/wireless/microchip/wilc1000/netdev.h
@@ -27,6 +27,8 @@ 
 #define TCP_ACK_FILTER_LINK_SPEED_THRESH	54
 #define DEFAULT_LINK_SPEED			72
 
+#define TX_BACKOFF_WEIGHT_MS 1
+
 struct wilc_wfi_stats {
 	unsigned long rx_packets;
 	unsigned long tx_packets;