[PATCH net 0/2] netdevsim: Two small fixes

[PATCH net 0/2] netdevsim: Two small fixes

[Ido Schimmel]

From: Ido Schimmel <idosch@mellanox.com>

Fix two bugs observed while analyzing regression failures.

Patch #1 fixes a bug where sometimes the drop counter of a packet trap
policer would not increase.

Patch #2 adds a missing initialization of a variable in a related
selftest.

Ido Schimmel (2):
  netdevsim: Ensure policer drop counter always increases
  selftests: netdevsim: Always initialize 'RET' variable

 drivers/net/netdevsim/dev.c                                   | 3 +--
 tools/testing/selftests/drivers/net/netdevsim/devlink_trap.sh | 4 ++++
 2 files changed, 5 insertions(+), 2 deletions(-)

-- 
2.26.2

[PATCH net 1/2] netdevsim: Ensure policer drop counter always increases

[Ido Schimmel]

From: Ido Schimmel <idosch@mellanox.com>

In case the policer drop counter is retrieved when the jiffies value is
a multiple of 64, the counter will not be incremented.

This randomly breaks a selftest [1] the reads the counter twice and
checks that it was incremented:

```
TEST: Trap policer                                                  [FAIL]
	Policer drop counter was not incremented
```

Fix by always incrementing the counter by 1.

[1] tools/testing/selftests/drivers/net/netdevsim/devlink_trap.sh

Fixes: ad188458d012 ("netdevsim: Add devlink-trap policer support")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
---
 drivers/net/netdevsim/dev.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/net/netdevsim/dev.c b/drivers/net/netdevsim/dev.c
index 68668a22b9dd..dc3ff0e20944 100644
--- a/drivers/net/netdevsim/dev.c
+++ b/drivers/net/netdevsim/dev.c
@@ -858,8 +858,7 @@ nsim_dev_devlink_trap_policer_counter_get(struct devlink *devlink,
 		return -EINVAL;
 
 	cnt = &nsim_dev->trap_data->trap_policers_cnt_arr[policer->id - 1];
-	*p_drops = *cnt;
-	*cnt += jiffies % 64;
+	*p_drops = (*cnt)++;
 
 	return 0;
 }
-- 
2.26.2

[PATCH net 2/2] selftests: netdevsim: Always initialize 'RET' variable

[Ido Schimmel]

From: Ido Schimmel <idosch@mellanox.com>

The variable is used by log_test() to check if the test case completely
successfully or not. In case it is not initialized at the start of a
test case, it is possible for the test case to fail despite not
encountering any errors.

Example:

```
...
TEST: Trap group statistics                                         [ OK ]
TEST: Trap policer                                                  [FAIL]
	Policer drop counter was not incremented
TEST: Trap policer binding                                          [FAIL]
	Policer drop counter was not incremented
```

Failure of trap_policer_test() caused trap_policer_bind_test() to fail
as well.

Fix by adding missing initialization of the variable.

Fixes: 5fbff58e27a1 ("selftests: netdevsim: Add test cases for devlink-trap policers")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
---
 tools/testing/selftests/drivers/net/netdevsim/devlink_trap.sh | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tools/testing/selftests/drivers/net/netdevsim/devlink_trap.sh b/tools/testing/selftests/drivers/net/netdevsim/devlink_trap.sh
index dbd1e014ba17..da49ad2761b5 100755
--- a/tools/testing/selftests/drivers/net/netdevsim/devlink_trap.sh
+++ b/tools/testing/selftests/drivers/net/netdevsim/devlink_trap.sh
@@ -264,6 +264,8 @@ trap_policer_test()
 	local packets_t0
 	local packets_t1
 
+	RET=0
+
 	if [ $(devlink_trap_policers_num_get) -eq 0 ]; then
 		check_err 1 "Failed to dump policers"
 	fi
@@ -328,6 +330,8 @@ trap_group_check_policer()
 
 trap_policer_bind_test()
 {
+	RET=0
+
 	devlink trap group set $DEVLINK_DEV group l2_drops policer 1
 	check_err $? "Failed to bind a valid policer"
 	if [ $(devlink_trap_group_policer_get "l2_drops") -ne 1 ]; then
-- 
2.26.2

Re: [PATCH net 0/2] netdevsim: Two small fixes

[Jakub Kicinski]

On Thu, 21 May 2020 14:46:15 +0300 Ido Schimmel wrote:
> From: Ido Schimmel <idosch@mellanox.com>
> 
> Fix two bugs observed while analyzing regression failures.
> 
> Patch #1 fixes a bug where sometimes the drop counter of a packet trap
> policer would not increase.
> 
> Patch #2 adds a missing initialization of a variable in a related
> selftest.

Acked-by: Jakub Kicinski <kuba@kernel.org>

Re: [PATCH net 0/2] netdevsim: Two small fixes

[David Miller]

From: Ido Schimmel <idosch@idosch.org>
Date: Thu, 21 May 2020 14:46:15 +0300

> From: Ido Schimmel <idosch@mellanox.com>
> 
> Fix two bugs observed while analyzing regression failures.
> 
> Patch #1 fixes a bug where sometimes the drop counter of a packet trap
> policer would not increase.
> 
> Patch #2 adds a missing initialization of a variable in a related
> selftest.

Series applied, thanks.