From: Prasad Kanneganti <prasad.kanneganti@cavium.com>
Date: Wed, 7 Mar 2018 22:23:32 -0800
Subject: liquidio: avoid doing useless work
Patch-mainline: v4.17-rc1
Git-commit: cecd8d81ac5a7551d70c331b7f4ef7eb2609f336
References: bsc#1119406 FATE#326562

Avoid doing useless work by making sure that the response_list is not empty
before scheduling work to process it.

Signed-off-by: Prasad Kanneganti <prasad.kanneganti@cavium.com>
Signed-off-by: Felix Manlunas <felix.manlunas@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/cavium/liquidio/request_manager.c  |    5 +++++
 drivers/net/ethernet/cavium/liquidio/response_manager.c |    6 ++++--
 2 files changed, 9 insertions(+), 2 deletions(-)

--- a/drivers/net/ethernet/cavium/liquidio/request_manager.c
+++ b/drivers/net/ethernet/cavium/liquidio/request_manager.c
@@ -366,6 +366,7 @@ int
 lio_process_iq_request_list(struct octeon_device *oct,
 			    struct octeon_instr_queue *iq, u32 napi_budget)
 {
+	struct cavium_wq *cwq = &oct->dma_comp_wq;
 	int reqtype;
 	void *buf;
 	u32 old = iq->flush_index;
@@ -450,6 +451,10 @@ lio_process_iq_request_list(struct octeo
 						   bytes_compl);
 	iq->flush_index = old;
 
+	if (atomic_read(&oct->response_list
+			[OCTEON_ORDERED_SC_LIST].pending_req_count))
+		queue_delayed_work(cwq->wq, &cwq->wk.work, msecs_to_jiffies(1));
+
 	return inst_count;
 }
 
--- a/drivers/net/ethernet/cavium/liquidio/response_manager.c
+++ b/drivers/net/ethernet/cavium/liquidio/response_manager.c
@@ -49,7 +49,6 @@ int octeon_setup_response_list(struct oc
 	INIT_DELAYED_WORK(&cwq->wk.work, oct_poll_req_completion);
 	cwq->wk.ctxptr = oct;
 	oct->cmd_resp_state = OCT_DRV_ONLINE;
-	queue_delayed_work(cwq->wq, &cwq->wk.work, msecs_to_jiffies(50));
 
 	return ret;
 }
@@ -164,5 +163,8 @@ static void oct_poll_req_completion(stru
 	struct cavium_wq *cwq = &oct->dma_comp_wq;
 
 	lio_process_ordered_list(oct, 0);
-	queue_delayed_work(cwq->wq, &cwq->wk.work, msecs_to_jiffies(50));
+
+	if (atomic_read(&oct->response_list
+			[OCTEON_ORDERED_SC_LIST].pending_req_count))
+		queue_delayed_work(cwq->wq, &cwq->wk.work, msecs_to_jiffies(1));
 }