[dpdk-stable] [PATCH] eal/linux: fix return after alarm registration failure

[dpdk-stable] [PATCH] eal/linux: fix return after alarm registration failure

[Thomas Monjalon]

When adding an alarm, if an error happen when registering
the common alarm callback, it is not considered as a major failure.
The alarm is then inserted in the list.
However it was returning an error code after inserting the alarm.

The error code is reset to 0 so the behaviour and the return code
are consistent.
Other return code related lines are cleaned up for easier understanding.

Fixes: af75078fece3 ("first public release")
Cc: stable@dpdk.org

Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
---
 lib/librte_eal/linux/eal/eal_alarm.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/lib/librte_eal/linux/eal/eal_alarm.c b/lib/librte_eal/linux/eal/eal_alarm.c
index 840ede780..d6d70e8c3 100644
--- a/lib/librte_eal/linux/eal/eal_alarm.c
+++ b/lib/librte_eal/linux/eal/eal_alarm.c
@@ -137,9 +137,13 @@ rte_eal_alarm_set(uint64_t us, rte_eal_alarm_callback cb_fn, void *cb_arg)
 
 	rte_spinlock_lock(&alarm_list_lk);
 	if (!handler_registered) {
-		ret |= rte_intr_callback_register(&intr_handle,
+		ret = rte_intr_callback_register(&intr_handle,
 				eal_alarm_callback, NULL);
-		handler_registered = (ret == 0) ? 1 : 0;
+		if (ret == 0)
+			handler_registered = 1;
+		else
+			/* not fatal, callback can be registered later */
+			ret = 0;
 	}
 
 	if (LIST_EMPTY(&alarm_list))
-- 
2.21.0

Re: [dpdk-stable] [PATCH] eal/linux: fix return after alarm registration failure

[David Marchand]

On Wed, Jun 26, 2019 at 12:41 PM Thomas Monjalon <thomas@monjalon.net>
wrote:

> When adding an alarm, if an error happen when registering
> the common alarm callback, it is not considered as a major failure.
> The alarm is then inserted in the list.
> However it was returning an error code after inserting the alarm.
>
> The error code is reset to 0 so the behaviour and the return code
> are consistent.
> Other return code related lines are cleaned up for easier understanding.
>
> Fixes: af75078fece3 ("first public release")
> Cc: stable@dpdk.org
>
> Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
> ---
>  lib/librte_eal/linux/eal/eal_alarm.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/lib/librte_eal/linux/eal/eal_alarm.c
> b/lib/librte_eal/linux/eal/eal_alarm.c
> index 840ede780..d6d70e8c3 100644
> --- a/lib/librte_eal/linux/eal/eal_alarm.c
> +++ b/lib/librte_eal/linux/eal/eal_alarm.c
> @@ -137,9 +137,13 @@ rte_eal_alarm_set(uint64_t us, rte_eal_alarm_callback
> cb_fn, void *cb_arg)
>
>         rte_spinlock_lock(&alarm_list_lk);
>         if (!handler_registered) {
> -               ret |= rte_intr_callback_register(&intr_handle,
> +               ret = rte_intr_callback_register(&intr_handle,
>                                 eal_alarm_callback, NULL);
> -               handler_registered = (ret == 0) ? 1 : 0;
> +               if (ret == 0)
> +                       handler_registered = 1;
> +               else
> +                       /* not fatal, callback can be registered later */
> +                       ret = 0;
>         }
>
>         if (LIST_EMPTY(&alarm_list))
>

Well, then it means that you don't want to touch ret at all.
How about:
if (rte_intr_callback_register(&intr_handle,
                               eal_alarm_callback, NULL) == 0)
        handler_registered = 1;

?


-- 
David Marchand

[dpdk-stable] [PATCH v2] eal/linux: fix return after alarm registration failure

[Thomas Monjalon]

When adding an alarm, if an error happen when registering
the common alarm callback, it is not considered as a major failure.
The alarm is then inserted in the list.
However it was returning an error code after inserting the alarm.

The error code is not set anymore to be consistent with the behaviour.

Fixes: af75078fece3 ("first public release")
Cc: stable@dpdk.org

Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
---
v2: do not use variable ret
---
 lib/librte_eal/linux/eal/eal_alarm.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/lib/librte_eal/linux/eal/eal_alarm.c b/lib/librte_eal/linux/eal/eal_alarm.c
index 840ede780..0924c9205 100644
--- a/lib/librte_eal/linux/eal/eal_alarm.c
+++ b/lib/librte_eal/linux/eal/eal_alarm.c
@@ -137,9 +137,10 @@ rte_eal_alarm_set(uint64_t us, rte_eal_alarm_callback cb_fn, void *cb_arg)
 
 	rte_spinlock_lock(&alarm_list_lk);
 	if (!handler_registered) {
-		ret |= rte_intr_callback_register(&intr_handle,
-				eal_alarm_callback, NULL);
-		handler_registered = (ret == 0) ? 1 : 0;
+		/* registration can fail, callback can be registered later */
+		if (rte_intr_callback_register(&intr_handle,
+				eal_alarm_callback, NULL) == 0)
+			handler_registered = 1;
 	}
 
 	if (LIST_EMPTY(&alarm_list))
-- 
2.21.0

Re: [dpdk-stable] [dpdk-dev] [PATCH v2] eal/linux: fix return after alarm registration failure

[Stephen Hemminger]

On Wed, 26 Jun 2019 16:02:34 +0200
Thomas Monjalon <thomas@monjalon.net> wrote:

> When adding an alarm, if an error happen when registering
> the common alarm callback, it is not considered as a major failure.
> The alarm is then inserted in the list.
> However it was returning an error code after inserting the alarm.
> 
> The error code is not set anymore to be consistent with the behaviour.
> 
> Fixes: af75078fece3 ("first public release")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
> ---
> v2: do not use variable ret

Acked-by: Stephen Hemminger <stephen@networkplumber.org>

Re: [dpdk-stable] [dpdk-dev] [PATCH v2] eal/linux: fix return after alarm registration failure

[Thomas Monjalon]

27/06/2019 01:09, Stephen Hemminger:
> On Wed, 26 Jun 2019 16:02:34 +0200
> Thomas Monjalon <thomas@monjalon.net> wrote:
> 
> > When adding an alarm, if an error happen when registering
> > the common alarm callback, it is not considered as a major failure.
> > The alarm is then inserted in the list.
> > However it was returning an error code after inserting the alarm.
> > 
> > The error code is not set anymore to be consistent with the behaviour.
> > 
> > Fixes: af75078fece3 ("first public release")
> > Cc: stable@dpdk.org
> > 
> > Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
> > ---
> > v2: do not use variable ret
> 
> Acked-by: Stephen Hemminger <stephen@networkplumber.org>

Applied