[dpdk-dev] [PATCH] net/failsafe: fix Rx interrupt reinstallation

[dpdk-dev] [PATCH] net/failsafe: fix Rx interrupt reinstallation

[Matan Azrad]

Fail-safe dev_start() operation can be called by both the application
and the hot-plug alarm mechanism.

The installation of Rx interrupt are triggered from dev_start() in any
time it is called while actually the Rx interrupt should be installed
only by the application calls.

So, each plug-in event causes reinstallation which causes memory leak.

Trigger the Rx interrupt installation only for application calls.

Fixes: 9e0360aebf23 ("net/failsafe: register as Rx interrupt mode")

Signed-off-by: Matan Azrad <matan@mellanox.com>
---
 drivers/net/failsafe/failsafe_ops.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/net/failsafe/failsafe_ops.c b/drivers/net/failsafe/failsafe_ops.c
index 057e435..bbbd335 100644
--- a/drivers/net/failsafe/failsafe_ops.c
+++ b/drivers/net/failsafe/failsafe_ops.c
@@ -181,10 +181,12 @@
 	int ret;
 
 	fs_lock(dev, 0);
-	ret = failsafe_rx_intr_install(dev);
-	if (ret) {
-		fs_unlock(dev, 0);
-		return ret;
+	if (PRIV(dev)->alarm_lock == 0) {
+		ret = failsafe_rx_intr_install(dev);
+		if (ret) {
+			fs_unlock(dev, 0);
+			return ret;
+		}
 	}
 	FOREACH_SUBDEV(sdev, i, dev) {
 		if (sdev->state != DEV_ACTIVE)
-- 
1.9.5

Re: [dpdk-dev] [PATCH] net/failsafe: fix Rx interrupt reinstallation

[Gaëtan Rivet]

Hi Matan,

On Tue, Feb 13, 2018 at 10:59:32PM +0000, Matan Azrad wrote:
> Fail-safe dev_start() operation can be called by both the application
> and the hot-plug alarm mechanism.
> 
> The installation of Rx interrupt are triggered from dev_start() in any
> time it is called while actually the Rx interrupt should be installed
> only by the application calls.
> 
> So, each plug-in event causes reinstallation which causes memory leak.
> 
> Trigger the Rx interrupt installation only for application calls.
> 
> Fixes: 9e0360aebf23 ("net/failsafe: register as Rx interrupt mode")
> 
> Signed-off-by: Matan Azrad <matan@mellanox.com>
> ---
>  drivers/net/failsafe/failsafe_ops.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/net/failsafe/failsafe_ops.c b/drivers/net/failsafe/failsafe_ops.c
> index 057e435..bbbd335 100644
> --- a/drivers/net/failsafe/failsafe_ops.c
> +++ b/drivers/net/failsafe/failsafe_ops.c
> @@ -181,10 +181,12 @@
>  	int ret;
>  
>  	fs_lock(dev, 0);
> -	ret = failsafe_rx_intr_install(dev);
> -	if (ret) {
> -		fs_unlock(dev, 0);
> -		return ret;
> +	if (PRIV(dev)->alarm_lock == 0) {

I dislike having to rely on unrelated context of execution to decide a
code-path.

I'd prefer to make interrupt installation dependent on the interrupt
state instead.

I think it should be possible to forbid reinstallation within
failsafe_rx_intr_install directly, e.g.

diff --git a/drivers/net/failsafe/failsafe_intr.c b/drivers/net/failsafe/failsafe_intr.c
index f6ff04dc8..46c3aa5f2 100644
--- a/drivers/net/failsafe/failsafe_intr.c
+++ b/drivers/net/failsafe/failsafe_intr.c
@@ -523,7 +523,8 @@ failsafe_rx_intr_install(struct rte_eth_dev *dev)
        const struct rte_intr_conf *const intr_conf =
                        &priv->dev->data->dev_conf.intr_conf;

-       if (intr_conf->rxq == 0)
+       if (intr_conf->rxq == 0 ||
+           dev->intr_handle != NULL)
                return 0;
        if (fs_rx_intr_vec_install(priv) < 0)
                return -rte_errno;

This way the logic is self-dependent and the check limited to this
component.

There might be better way to do this, it's only an example to explain my
point.

> +		ret = failsafe_rx_intr_install(dev);
> +		if (ret) {
> +			fs_unlock(dev, 0);
> +			return ret;
> +		}
>  	}
>  	FOREACH_SUBDEV(sdev, i, dev) {
>  		if (sdev->state != DEV_ACTIVE)
> -- 
> 1.9.5
> 

-- 
Gaëtan Rivet
6WIND

Re: [dpdk-dev] [PATCH] net/failsafe: fix Rx interrupt reinstallation

[Matan Azrad]

Hi Gaetan

Agree, will send V2.

> -----Original Message-----
> From: Gaëtan Rivet [mailto:gaetan.rivet@6wind.com]
> Sent: Wednesday, February 14, 2018 3:52 PM
> To: Matan Azrad <matan@mellanox.com>
> Cc: dev@dpdk.org
> Subject: Re: [PATCH] net/failsafe: fix Rx interrupt reinstallation
> 
> Hi Matan,
> 
> On Tue, Feb 13, 2018 at 10:59:32PM +0000, Matan Azrad wrote:
> > Fail-safe dev_start() operation can be called by both the application
> > and the hot-plug alarm mechanism.
> >
> > The installation of Rx interrupt are triggered from dev_start() in any
> > time it is called while actually the Rx interrupt should be installed
> > only by the application calls.
> >
> > So, each plug-in event causes reinstallation which causes memory leak.
> >
> > Trigger the Rx interrupt installation only for application calls.
> >
> > Fixes: 9e0360aebf23 ("net/failsafe: register as Rx interrupt mode")
> >
> > Signed-off-by: Matan Azrad <matan@mellanox.com>
> > ---
> >  drivers/net/failsafe/failsafe_ops.c | 10 ++++++----
> >  1 file changed, 6 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/net/failsafe/failsafe_ops.c
> > b/drivers/net/failsafe/failsafe_ops.c
> > index 057e435..bbbd335 100644
> > --- a/drivers/net/failsafe/failsafe_ops.c
> > +++ b/drivers/net/failsafe/failsafe_ops.c
> > @@ -181,10 +181,12 @@
> >  	int ret;
> >
> >  	fs_lock(dev, 0);
> > -	ret = failsafe_rx_intr_install(dev);
> > -	if (ret) {
> > -		fs_unlock(dev, 0);
> > -		return ret;
> > +	if (PRIV(dev)->alarm_lock == 0) {
> 
> I dislike having to rely on unrelated context of execution to decide a code-
> path.
> 
> I'd prefer to make interrupt installation dependent on the interrupt state
> instead.
> 
> I think it should be possible to forbid reinstallation within
> failsafe_rx_intr_install directly, e.g.
> 
> diff --git a/drivers/net/failsafe/failsafe_intr.c
> b/drivers/net/failsafe/failsafe_intr.c
> index f6ff04dc8..46c3aa5f2 100644
> --- a/drivers/net/failsafe/failsafe_intr.c
> +++ b/drivers/net/failsafe/failsafe_intr.c
> @@ -523,7 +523,8 @@ failsafe_rx_intr_install(struct rte_eth_dev *dev)
>         const struct rte_intr_conf *const intr_conf =
>                         &priv->dev->data->dev_conf.intr_conf;
> 
> -       if (intr_conf->rxq == 0)
> +       if (intr_conf->rxq == 0 ||
> +           dev->intr_handle != NULL)
>                 return 0;
>         if (fs_rx_intr_vec_install(priv) < 0)
>                 return -rte_errno;
> 
> This way the logic is self-dependent and the check limited to this component.
> 
> There might be better way to do this, it's only an example to explain my
> point.
> 
> > +		ret = failsafe_rx_intr_install(dev);
> > +		if (ret) {
> > +			fs_unlock(dev, 0);
> > +			return ret;
> > +		}
> >  	}
> >  	FOREACH_SUBDEV(sdev, i, dev) {
> >  		if (sdev->state != DEV_ACTIVE)
> > --
> > 1.9.5
> >
> 
> --
> Gaëtan Rivet
> 6WIND

[dpdk-dev] [PATCH v2] net/failsafe: fix Rx interrupt reinstallation

[Matan Azrad]

Fail-safe dev_start() operation can be called by both the application
and the hot-plug alarm mechanism.

The installation of Rx interrupt are triggered from dev_start() in any
time it is called while actually the Rx interrupt should be installed
only by the application calls.

So, each plug-in event causes reinstallation which causes memory leak
and spoils the fail-safe Rx interrupt mechanism.

Trigger the Rx interrupt installation only when it does not exist.

Fixes: 9e0360aebf23 ("net/failsafe: register as Rx interrupt mode")

Signed-off-by: Matan Azrad <matan@mellanox.com>
---
 drivers/net/failsafe/failsafe_intr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/failsafe/failsafe_intr.c b/drivers/net/failsafe/failsafe_intr.c
index f6ff04d..6b7f9c1 100644
--- a/drivers/net/failsafe/failsafe_intr.c
+++ b/drivers/net/failsafe/failsafe_intr.c
@@ -523,7 +523,7 @@ void failsafe_rx_intr_uninstall_subdevice(struct sub_device *sdev)
 	const struct rte_intr_conf *const intr_conf =
 			&priv->dev->data->dev_conf.intr_conf;
 
-	if (intr_conf->rxq == 0)
+	if (intr_conf->rxq == 0 || dev->intr_handle != NULL)
 		return 0;
 	if (fs_rx_intr_vec_install(priv) < 0)
 		return -rte_errno;
-- 
1.9.5

Re: [dpdk-dev] [PATCH v2] net/failsafe: fix Rx interrupt reinstallation

[Gaëtan Rivet]

On Wed, Feb 14, 2018 at 02:47:26PM +0000, Matan Azrad wrote:
> Fail-safe dev_start() operation can be called by both the application
> and the hot-plug alarm mechanism.
> 
> The installation of Rx interrupt are triggered from dev_start() in any
> time it is called while actually the Rx interrupt should be installed
> only by the application calls.
> 
> So, each plug-in event causes reinstallation which causes memory leak
> and spoils the fail-safe Rx interrupt mechanism.
> 
> Trigger the Rx interrupt installation only when it does not exist.
> 
> Fixes: 9e0360aebf23 ("net/failsafe: register as Rx interrupt mode")
> 
> Signed-off-by: Matan Azrad <matan@mellanox.com>

Acked-by: Gaetan Rivet <gaetan.rivet@6wind.com>

-- 
Gaëtan Rivet
6WIND

Re: [dpdk-dev] [PATCH v2] net/failsafe: fix Rx interrupt reinstallation

[Gaëtan Rivet]

On Wed, Feb 14, 2018 at 04:00:13PM +0100, Gaëtan Rivet wrote:
> On Wed, Feb 14, 2018 at 02:47:26PM +0000, Matan Azrad wrote:
> > Fail-safe dev_start() operation can be called by both the application
> > and the hot-plug alarm mechanism.
> > 
> > The installation of Rx interrupt are triggered from dev_start() in any
> > time it is called while actually the Rx interrupt should be installed
> > only by the application calls.
> > 
> > So, each plug-in event causes reinstallation which causes memory leak
> > and spoils the fail-safe Rx interrupt mechanism.
> > 
> > Trigger the Rx interrupt installation only when it does not exist.
> > 
> > Fixes: 9e0360aebf23 ("net/failsafe: register as Rx interrupt mode")
> > 
> > Signed-off-by: Matan Azrad <matan@mellanox.com>
> 
> Acked-by: Gaetan Rivet <gaetan.rivet@6wind.com>

Actually no!

There is a mistake in the patch, you disabled the uninstall, instead of
the installation.

-- 
Gaëtan Rivet
6WIND

Re: [dpdk-dev] [PATCH v2] net/failsafe: fix Rx interrupt reinstallation

[Matan Azrad]

Hi Gaetan

From: Gaëtan Rivet, Sent: Wednesday, February 14, 2018 5:01 PM
> On Wed, Feb 14, 2018 at 04:00:13PM +0100, Gaëtan Rivet wrote:
> > On Wed, Feb 14, 2018 at 02:47:26PM +0000, Matan Azrad wrote:
> > > Fail-safe dev_start() operation can be called by both the
> > > application and the hot-plug alarm mechanism.
> > >
> > > The installation of Rx interrupt are triggered from dev_start() in
> > > any time it is called while actually the Rx interrupt should be
> > > installed only by the application calls.
> > >
> > > So, each plug-in event causes reinstallation which causes memory
> > > leak and spoils the fail-safe Rx interrupt mechanism.
> > >
> > > Trigger the Rx interrupt installation only when it does not exist.
> > >
> > > Fixes: 9e0360aebf23 ("net/failsafe: register as Rx interrupt mode")
> > >
> > > Signed-off-by: Matan Azrad <matan@mellanox.com>
> >
> > Acked-by: Gaetan Rivet <gaetan.rivet@6wind.com>
> 
> Actually no!
> 
> There is a mistake in the patch, you disabled the uninstall, instead of the
> installation.
>
No Gaetan, I think it is in the install.
Please recheck maybe by applying.
 
> --
> Gaëtan Rivet
> 6WIND

Re: [dpdk-dev] [PATCH v2] net/failsafe: fix Rx interrupt reinstallation

[Gaëtan Rivet]

On Wed, Feb 14, 2018 at 04:01:29PM +0100, Gaëtan Rivet wrote:
> On Wed, Feb 14, 2018 at 04:00:13PM +0100, Gaëtan Rivet wrote:
> > On Wed, Feb 14, 2018 at 02:47:26PM +0000, Matan Azrad wrote:
> > > Fail-safe dev_start() operation can be called by both the application
> > > and the hot-plug alarm mechanism.
> > > 
> > > The installation of Rx interrupt are triggered from dev_start() in any
> > > time it is called while actually the Rx interrupt should be installed
> > > only by the application calls.
> > > 
> > > So, each plug-in event causes reinstallation which causes memory leak
> > > and spoils the fail-safe Rx interrupt mechanism.
> > > 
> > > Trigger the Rx interrupt installation only when it does not exist.
> > > 
> > > Fixes: 9e0360aebf23 ("net/failsafe: register as Rx interrupt mode")
> > > 
> > > Signed-off-by: Matan Azrad <matan@mellanox.com>
> > 
> > Acked-by: Gaetan Rivet <gaetan.rivet@6wind.com>
> 
> Actually no!
> 
> There is a mistake in the patch, you disabled the uninstall, instead of
> the installation.

Okay, this is weird.

> > > Fail-safe dev_start() operation can be called by both the application
> > > and the hot-plug alarm mechanism.
> > > 
> > > The installation of Rx interrupt are triggered from dev_start() in any
> > > time it is called while actually the Rx interrupt should be installed
> > > only by the application calls.
> > > 
> > > So, each plug-in event causes reinstallation which causes memory leak
> > > and spoils the fail-safe Rx interrupt mechanism.
> > > 
> > > Trigger the Rx interrupt installation only when it does not exist.
> > > 
> > > Fixes: 9e0360aebf23 ("net/failsafe: register as Rx interrupt mode")
> > > 
> > > Signed-off-by: Matan Azrad <matan@mellanox.com>
> > > ---
> > >  drivers/net/failsafe/failsafe_intr.c | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/net/failsafe/failsafe_intr.c b/drivers/net/failsafe/failsafe_intr.c
> > > index f6ff04d..6b7f9c1 100644
> > > --- a/drivers/net/failsafe/failsafe_intr.c
> > > +++ b/drivers/net/failsafe/failsafe_intr.c
> > > @@ -523,7 +523,7 @@ void failsafe_rx_intr_uninstall_subdevice(struct sub_device *sdev)

Here the context is incorrect, this is not within failsafe_rx_intr_uninstall_subdevice,
so the fix is correct. Confirming my ack then, this seems like a
format-patch bug or something.

> > >         const struct rte_intr_conf *const intr_conf =
> > >                         &priv->dev->data->dev_conf.intr_conf;
> > > 
> > > -       if (intr_conf->rxq == 0)
> > > +       if (intr_conf->rxq == 0 || dev->intr_handle != NULL)
> > >                 return 0;
> > >         if (fs_rx_intr_vec_install(priv) < 0)
> > >                 return -rte_errno;
> > > --
> > > 1.9.5



-- 
Gaëtan Rivet
6WIND

Re: [dpdk-dev] [PATCH v2] net/failsafe: fix Rx interrupt reinstallation

[Thomas Monjalon]

14/02/2018 16:00, Gaëtan Rivet:
> On Wed, Feb 14, 2018 at 02:47:26PM +0000, Matan Azrad wrote:
> > Fail-safe dev_start() operation can be called by both the application
> > and the hot-plug alarm mechanism.
> > 
> > The installation of Rx interrupt are triggered from dev_start() in any
> > time it is called while actually the Rx interrupt should be installed
> > only by the application calls.
> > 
> > So, each plug-in event causes reinstallation which causes memory leak
> > and spoils the fail-safe Rx interrupt mechanism.
> > 
> > Trigger the Rx interrupt installation only when it does not exist.
> > 
> > Fixes: 9e0360aebf23 ("net/failsafe: register as Rx interrupt mode")
> > 
> > Signed-off-by: Matan Azrad <matan@mellanox.com>
> 
> Acked-by: Gaetan Rivet <gaetan.rivet@6wind.com>

Applied, thanks