[dpdk-stable] patch 'net/hns3: fix timing of clearing interrupt source' has been queued to stable release 20.11.3

[luca.boccassi at gmail.com]

Hi,

FYI, your patch has been queued to stable release 20.11.3

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 07/28/21. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the
patch applied to the branch. This will indicate if there was any rebasing
needed to apply to the stable branch. If there were code changes for rebasing
(ie: not only metadata diffs), please double check that the rebase was
correctly done.

Queued patches are on a temporary branch at:
https://github.com/bluca/dpdk-stable

This queued commit can be viewed at:
https://github.com/bluca/dpdk-stable/commit/fc0e7a4358b0245b8386240693d070385937490f

Thanks.

Luca Boccassi

---
>From fc0e7a4358b0245b8386240693d070385937490f Mon Sep 17 00:00:00 2001
From: Hongbo Zheng <zhenghongbo3 at huawei.com>
Date: Sat, 17 Jul 2021 10:02:52 +0800
Subject: [PATCH] net/hns3: fix timing of clearing interrupt source

[ upstream commit ee930d38ffca82af6c70209be7a8f2b408dc5610 ]

Currently, the PF/VF does not clear the interrupt source immediately
after receiving the interrupt. As a result, if the second interrupt
task is triggered when processing the first interrupt task, clearing
the interrupt source before exiting will clear the interrupt sources
of the two tasks at the same time. As a result, no interrupt is
triggered for the second task.

Clearing interrupt source immediately after checking event cause
ensures that:
1. Even if two interrupt tasks are triggered at the same time, they can
be processed.
2. If the second task is triggered during the processing of the first
task and the interrupt source is not cleared, the interrupt is reported
after vector0 is enabled.

Fixes: a5475d61fa34 ("net/hns3: support VF")
Fixes: 3988ab0eee52 ("net/hns3: add abnormal interrupt process")

Signed-off-by: Hongbo Zheng <zhenghongbo3 at huawei.com>
Signed-off-by: Min Hu (Connor) <humin29 at huawei.com>
---
 drivers/net/hns3/hns3_ethdev.c    | 2 +-
 drivers/net/hns3/hns3_ethdev_vf.c | 5 ++---
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/net/hns3/hns3_ethdev.c b/drivers/net/hns3/hns3_ethdev.c
index 1ddb2e1806..25a9af4382 100644
--- a/drivers/net/hns3/hns3_ethdev.c
+++ b/drivers/net/hns3/hns3_ethdev.c
@@ -239,6 +239,7 @@ hns3_interrupt_handler(void *param)
 	hns3_pf_disable_irq0(hw);
 
 	event_cause = hns3_check_event_cause(hns, &clearval);
+	hns3_clear_event_cause(hw, event_cause, clearval);
 	/* vector 0 interrupt is shared with reset and mailbox source events. */
 	if (event_cause == HNS3_VECTOR0_EVENT_ERR) {
 		hns3_warn(hw, "Received err interrupt");
@@ -253,7 +254,6 @@ hns3_interrupt_handler(void *param)
 	else
 		hns3_err(hw, "Received unknown event");
 
-	hns3_clear_event_cause(hw, event_cause, clearval);
 	/* Enable interrupt if it is not cause by reset */
 	hns3_pf_enable_irq0(hw);
 }
diff --git a/drivers/net/hns3/hns3_ethdev_vf.c b/drivers/net/hns3/hns3_ethdev_vf.c
index 913484d2e3..24bc540456 100644
--- a/drivers/net/hns3/hns3_ethdev_vf.c
+++ b/drivers/net/hns3/hns3_ethdev_vf.c
@@ -1116,6 +1116,8 @@ hns3vf_interrupt_handler(void *param)
 
 	/* Read out interrupt causes */
 	event_cause = hns3vf_check_event_cause(hns, &clearval);
+	/* Clear interrupt causes */
+	hns3vf_clear_event_cause(hw, clearval);
 
 	switch (event_cause) {
 	case HNS3VF_VECTOR0_EVENT_RST:
@@ -1128,9 +1130,6 @@ hns3vf_interrupt_handler(void *param)
 		break;
 	}
 
-	/* Clear interrupt causes */
-	hns3vf_clear_event_cause(hw, clearval);
-
 	/* Enable interrupt */
 	hns3vf_enable_irq0(hw);
 }
-- 
2.30.2

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2021-07-26 13:53:18.109997104 +0100
+++ 0042-net-hns3-fix-timing-of-clearing-interrupt-source.patch	2021-07-26 13:53:15.917294052 +0100
@@ -1 +1 @@
-From ee930d38ffca82af6c70209be7a8f2b408dc5610 Mon Sep 17 00:00:00 2001
+From fc0e7a4358b0245b8386240693d070385937490f Mon Sep 17 00:00:00 2001
@@ -5,0 +6,2 @@
+[ upstream commit ee930d38ffca82af6c70209be7a8f2b408dc5610 ]
+
@@ -23 +24,0 @@
-Cc: stable at dpdk.org
@@ -33 +34 @@
-index 3699b5636e..f994c288a1 100644
+index 1ddb2e1806..25a9af4382 100644
@@ -36,4 +37,4 @@
-@@ -317,6 +317,7 @@ hns3_interrupt_handler(void *param)
- 	vector0_int = hns3_read_dev(hw, HNS3_VECTOR0_OTHER_INT_STS_REG);
- 	ras_int = hns3_read_dev(hw, HNS3_RAS_PF_OTHER_INT_STS_REG);
- 	cmdq_int = hns3_read_dev(hw, HNS3_VECTOR0_CMDQ_SRC_REG);
+@@ -239,6 +239,7 @@ hns3_interrupt_handler(void *param)
+ 	hns3_pf_disable_irq0(hw);
+ 
+ 	event_cause = hns3_check_event_cause(hns, &clearval);
@@ -43,4 +44,4 @@
- 		hns3_warn(hw, "received interrupt: vector0_int_stat:0x%x "
-@@ -335,7 +336,6 @@ hns3_interrupt_handler(void *param)
- 			  vector0_int, ras_int, cmdq_int);
- 	}
+ 		hns3_warn(hw, "Received err interrupt");
+@@ -253,7 +254,6 @@ hns3_interrupt_handler(void *param)
+ 	else
+ 		hns3_err(hw, "Received unknown event");
@@ -53 +54 @@
-index 8f3be64b0b..de659c05f0 100644
+index 913484d2e3..24bc540456 100644