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From: Govindarajulu Varadarajan <gvaradar@cisco.com>
Date: Thu, 21 Dec 2017 08:12:28 -0800
Subject: enic: add wq clean up budget
Patch-mainline: v4.16-rc1
Git-commit: 18feb87105c3c16dc01e6981a6aafb175679b997
References: bsc#1075697

In case of tx clean up, we set '-1' as budget. This means clean up until
wq is empty or till (1 << 32) pkts are cleaned. Under heavy load this
will run for long time and cause
"watchdog: BUG: soft lockup - CPU#25 stuck for 21s!" warning.

This patch sets wq clean up budget to 256.

Signed-off-by: Govindarajulu Varadarajan <gvaradar@cisco.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/cisco/enic/enic.h      |    2 ++
 drivers/net/ethernet/cisco/enic/enic_main.c |    4 ++--
 2 files changed, 4 insertions(+), 2 deletions(-)

--- a/drivers/net/ethernet/cisco/enic/enic.h
+++ b/drivers/net/ethernet/cisco/enic/enic.h
@@ -43,6 +43,8 @@
 #define ENIC_CQ_MAX		(ENIC_WQ_MAX + ENIC_RQ_MAX)
 #define ENIC_INTR_MAX		(ENIC_CQ_MAX + 2)
 
+#define ENIC_WQ_NAPI_BUDGET	256
+
 #define ENIC_AIC_LARGE_PKT_DIFF	3
 
 struct enic_msix_entry {
--- a/drivers/net/ethernet/cisco/enic/enic_main.c
+++ b/drivers/net/ethernet/cisco/enic/enic_main.c
@@ -1499,7 +1499,7 @@ static int enic_poll(struct napi_struct
 	unsigned int cq_wq = enic_cq_wq(enic, 0);
 	unsigned int intr = enic_legacy_io_intr();
 	unsigned int rq_work_to_do = budget;
-	unsigned int wq_work_to_do = -1; /* no limit */
+	unsigned int wq_work_to_do = ENIC_WQ_NAPI_BUDGET;
 	unsigned int  work_done, rq_work_done = 0, wq_work_done;
 	int err;
 
@@ -1597,7 +1597,7 @@ static int enic_poll_msix_wq(struct napi
 	struct vnic_wq *wq = &enic->wq[wq_index];
 	unsigned int cq;
 	unsigned int intr;
-	unsigned int wq_work_to_do = -1; /* clean all desc possible */
+	unsigned int wq_work_to_do = ENIC_WQ_NAPI_BUDGET;
 	unsigned int wq_work_done;
 	unsigned int wq_irq;