net: cnic: Convert tasklet API to new bottom half workqueue mechanism

Migrate tasklet APIs to the new bottom half workqueue mechanism. It
replaces all occurrences of tasklet usage with the appropriate workqueue
APIs throughout the cnic driver. This transition ensures compatibility
with the latest design and enhances performance.

Signed-off-by: Allen Pais <allen.lkml@gmail.com>
Link: https://patch.msgid.link/20240730183403.4176544-4-allen.lkml@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/broadcom/cnic.c

@@ -31,6 +31,7 @@
 #include <linux/if_vlan.h>
 #include <linux/prefetch.h>
 #include <linux/random.h>
+#include <linux/workqueue.h>
 #if IS_ENABLED(CONFIG_VLAN_8021Q)
 #define BCM_VLAN 1
 #endif
@@ -3015,9 +3016,9 @@ static int cnic_service_bnx2(void *data, void *status_blk)
 	return cnic_service_bnx2_queues(dev);
 }
 
-static void cnic_service_bnx2_msix(struct tasklet_struct *t)
+static void cnic_service_bnx2_msix(struct work_struct *work)
 {
-	struct cnic_local *cp = from_tasklet(cp, t, cnic_irq_task);
+	struct cnic_local *cp = from_work(cp, work, cnic_irq_bh_work);
 	struct cnic_dev *dev = cp->dev;
 
 	cp->last_status_idx = cnic_service_bnx2_queues(dev);
@@ -3036,7 +3037,7 @@ static void cnic_doirq(struct cnic_dev *dev)
 		prefetch(cp->status_blk.gen);
 		prefetch(&cp->kcq1.kcq[KCQ_PG(prod)][KCQ_IDX(prod)]);
 
-		tasklet_schedule(&cp->cnic_irq_task);
+		queue_work(system_bh_wq, &cp->cnic_irq_bh_work);
 	}
 }
 
@@ -3140,9 +3141,9 @@ static u32 cnic_service_bnx2x_kcq(struct cnic_dev *dev, struct kcq_info *info)
 	return last_status;
 }
 
-static void cnic_service_bnx2x_bh(struct tasklet_struct *t)
+static void cnic_service_bnx2x_bh_work(struct work_struct *work)
 {
-	struct cnic_local *cp = from_tasklet(cp, t, cnic_irq_task);
+	struct cnic_local *cp = from_work(cp, work, cnic_irq_bh_work);
 	struct cnic_dev *dev = cp->dev;
 	struct bnx2x *bp = netdev_priv(dev->netdev);
 	u32 status_idx, new_status_idx;
@@ -4428,7 +4429,7 @@ static void cnic_free_irq(struct cnic_dev *dev)
 
 	if (ethdev->drv_state & CNIC_DRV_STATE_USING_MSIX) {
 		cp->disable_int_sync(dev);
-		tasklet_kill(&cp->cnic_irq_task);
+		cancel_work_sync(&cp->cnic_irq_bh_work);
 		free_irq(ethdev->irq_arr[0].vector, dev);
 	}
 }
@@ -4441,7 +4442,7 @@ static int cnic_request_irq(struct cnic_dev *dev)
 
 	err = request_irq(ethdev->irq_arr[0].vector, cnic_irq, 0, "cnic", dev);
 	if (err)
-		tasklet_disable(&cp->cnic_irq_task);
+		disable_work_sync(&cp->cnic_irq_bh_work);
 
 	return err;
 }
@@ -4464,7 +4465,7 @@ static int cnic_init_bnx2_irq(struct cnic_dev *dev)
 		CNIC_WR(dev, base + BNX2_HC_CMD_TICKS_OFF, (64 << 16) | 220);
 
 		cp->last_status_idx = cp->status_blk.bnx2->status_idx;
-		tasklet_setup(&cp->cnic_irq_task, cnic_service_bnx2_msix);
+		INIT_WORK(&cp->cnic_irq_bh_work, cnic_service_bnx2_msix);
 		err = cnic_request_irq(dev);
 		if (err)
 			return err;
@@ -4873,7 +4874,7 @@ static int cnic_init_bnx2x_irq(struct cnic_dev *dev)
 	struct cnic_eth_dev *ethdev = cp->ethdev;
 	int err = 0;
 
-	tasklet_setup(&cp->cnic_irq_task, cnic_service_bnx2x_bh);
+	INIT_WORK(&cp->cnic_irq_bh_work, cnic_service_bnx2x_bh_work);
 	if (ethdev->drv_state & CNIC_DRV_STATE_USING_MSIX)
 		err = cnic_request_irq(dev);
 

drivers/net/ethernet/broadcom/cnic.h

@@ -268,7 +268,7 @@ struct cnic_local {
 	u32				bnx2x_igu_sb_id;
 	u32				int_num;
 	u32				last_status_idx;
-	struct tasklet_struct		cnic_irq_task;
+	struct work_struct		cnic_irq_bh_work;
 
 	struct kcqe		*completed_kcq[MAX_COMPLETED_KCQE];