[dpdk-dev] [PATCH] net/virtio: wait device ready in device reset

[dpdk-dev] [PATCH] net/virtio: wait device ready in device reset

[Xueming Li]

According to virtio spec, the device MUST reset when 0 is written to
device_status, and present a 0 in device_status once that is done.

This patch adds the missing part of waiting status 0 in reset function.

Signed-off-by: Xueming Li <xuemingl@nvidia.com>
---
 drivers/net/virtio/virtio.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/net/virtio/virtio.c b/drivers/net/virtio/virtio.c
index 7e1e77797f..f003f612d6 100644
--- a/drivers/net/virtio/virtio.c
+++ b/drivers/net/virtio/virtio.c
@@ -3,6 +3,8 @@
  * Copyright(c) 2020 Red Hat, Inc.
  */
 
+#include <unistd.h>
+
 #include "virtio.h"
 
 uint64_t
@@ -39,8 +41,9 @@ void
 virtio_reset(struct virtio_hw *hw)
 {
 	VIRTIO_OPS(hw)->set_status(hw, VIRTIO_CONFIG_STATUS_RESET);
-	/* flush status write */
-	VIRTIO_OPS(hw)->get_status(hw);
+	/* Flush status write and wait device ready. */
+	while (VIRTIO_OPS(hw)->get_status(hw) != VIRTIO_CONFIG_STATUS_RESET)
+		usleep(1000L);
 }
 
 void
-- 
2.25.1

Re: [dpdk-dev] [PATCH] net/virtio: wait device ready in device reset

[Andrew Rybchenko]

On 8/23/21 9:39 AM, Xueming Li wrote:
> According to virtio spec, the device MUST reset when 0 is written to
> device_status, and present a 0 in device_status once that is done.
> 
> This patch adds the missing part of waiting status 0 in reset function.
> 
> Signed-off-by: Xueming Li <xuemingl@nvidia.com>
> ---
>  drivers/net/virtio/virtio.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/virtio/virtio.c b/drivers/net/virtio/virtio.c
> index 7e1e77797f..f003f612d6 100644
> --- a/drivers/net/virtio/virtio.c
> +++ b/drivers/net/virtio/virtio.c
> @@ -3,6 +3,8 @@
>   * Copyright(c) 2020 Red Hat, Inc.
>   */
>  
> +#include <unistd.h>
> +
>  #include "virtio.h"
>  
>  uint64_t
> @@ -39,8 +41,9 @@ void
>  virtio_reset(struct virtio_hw *hw)
>  {
>  	VIRTIO_OPS(hw)->set_status(hw, VIRTIO_CONFIG_STATUS_RESET);
> -	/* flush status write */
> -	VIRTIO_OPS(hw)->get_status(hw);
> +	/* Flush status write and wait device ready. */
> +	while (VIRTIO_OPS(hw)->get_status(hw) != VIRTIO_CONFIG_STATUS_RESET)
> +		usleep(1000L);

Don't we need a protection against forever loop here?

>  }
>  
>  void
> 

Re: [dpdk-dev] [PATCH] net/virtio: wait device ready in device reset

[Xueming(Steven) Li]

> -----Original Message-----
> From: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
> Sent: Monday, August 23, 2021 5:57 PM
> To: Xueming(Steven) Li <xuemingl@nvidia.com>
> Cc: dev@dpdk.org; Maxime Coquelin <maxime.coquelin@redhat.com>; Chenbo Xia <chenbo.xia@intel.com>
> Subject: Re: [dpdk-dev] [PATCH] net/virtio: wait device ready in device reset
> 
> On 8/23/21 9:39 AM, Xueming Li wrote:
> > According to virtio spec, the device MUST reset when 0 is written to
> > device_status, and present a 0 in device_status once that is done.
> >
> > This patch adds the missing part of waiting status 0 in reset function.
> >
> > Signed-off-by: Xueming Li <xuemingl@nvidia.com>
> > ---
> >  drivers/net/virtio/virtio.c | 7 +++++--
> >  1 file changed, 5 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/net/virtio/virtio.c b/drivers/net/virtio/virtio.c
> > index 7e1e77797f..f003f612d6 100644
> > --- a/drivers/net/virtio/virtio.c
> > +++ b/drivers/net/virtio/virtio.c
> > @@ -3,6 +3,8 @@
> >   * Copyright(c) 2020 Red Hat, Inc.
> >   */
> >
> > +#include <unistd.h>
> > +
> >  #include "virtio.h"
> >
> >  uint64_t
> > @@ -39,8 +41,9 @@ void
> >  virtio_reset(struct virtio_hw *hw)
> >  {
> >  	VIRTIO_OPS(hw)->set_status(hw, VIRTIO_CONFIG_STATUS_RESET);
> > -	/* flush status write */
> > -	VIRTIO_OPS(hw)->get_status(hw);
> > +	/* Flush status write and wait device ready. */
> > +	while (VIRTIO_OPS(hw)->get_status(hw) != VIRTIO_CONFIG_STATUS_RESET)
> > +		usleep(1000L);
> 
> Don't we need a protection against forever loop here?

Good question, ideally we need, kernel driver function vp_reset() seems to have same issue.
How about leaving an error message before return? 

> 
> >  }
> >
> >  void
> >

Re: [dpdk-dev] [PATCH] net/virtio: wait device ready in device reset

[Andrew Rybchenko]

On 8/23/21 4:54 PM, Xueming(Steven) Li wrote:
> 
> 
>> -----Original Message-----
>> From: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
>> Sent: Monday, August 23, 2021 5:57 PM
>> To: Xueming(Steven) Li <xuemingl@nvidia.com>
>> Cc: dev@dpdk.org; Maxime Coquelin <maxime.coquelin@redhat.com>; Chenbo Xia <chenbo.xia@intel.com>
>> Subject: Re: [dpdk-dev] [PATCH] net/virtio: wait device ready in device reset
>>
>> On 8/23/21 9:39 AM, Xueming Li wrote:
>>> According to virtio spec, the device MUST reset when 0 is written to
>>> device_status, and present a 0 in device_status once that is done.
>>>
>>> This patch adds the missing part of waiting status 0 in reset function.
>>>
>>> Signed-off-by: Xueming Li <xuemingl@nvidia.com>
>>> ---
>>>  drivers/net/virtio/virtio.c | 7 +++++--
>>>  1 file changed, 5 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/net/virtio/virtio.c b/drivers/net/virtio/virtio.c
>>> index 7e1e77797f..f003f612d6 100644
>>> --- a/drivers/net/virtio/virtio.c
>>> +++ b/drivers/net/virtio/virtio.c
>>> @@ -3,6 +3,8 @@
>>>   * Copyright(c) 2020 Red Hat, Inc.
>>>   */
>>>
>>> +#include <unistd.h>
>>> +
>>>  #include "virtio.h"
>>>
>>>  uint64_t
>>> @@ -39,8 +41,9 @@ void
>>>  virtio_reset(struct virtio_hw *hw)
>>>  {
>>>  	VIRTIO_OPS(hw)->set_status(hw, VIRTIO_CONFIG_STATUS_RESET);
>>> -	/* flush status write */
>>> -	VIRTIO_OPS(hw)->get_status(hw);
>>> +	/* Flush status write and wait device ready. */
>>> +	while (VIRTIO_OPS(hw)->get_status(hw) != VIRTIO_CONFIG_STATUS_RESET)
>>> +		usleep(1000L);
>>
>> Don't we need a protection against forever loop here?
> 
> Good question, ideally we need, kernel driver function vp_reset() seems to have same issue.

Yes, I've seen it.

> How about leaving an error message before return? 

@Maxime, @Chenbo, what do you think?

Re: [dpdk-dev] [PATCH] net/virtio: wait device ready in device reset

[Xia, Chenbo]

Hi Adrew & Xueming,

> -----Original Message-----
> From: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
> Sent: Tuesday, August 24, 2021 11:41 PM
> To: Xueming(Steven) Li <xuemingl@nvidia.com>
> Cc: dev@dpdk.org; Maxime Coquelin <maxime.coquelin@redhat.com>; Xia, Chenbo
> <chenbo.xia@intel.com>
> Subject: Re: [dpdk-dev] [PATCH] net/virtio: wait device ready in device reset
> 
> On 8/23/21 4:54 PM, Xueming(Steven) Li wrote:
> >
> >
> >> -----Original Message-----
> >> From: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
> >> Sent: Monday, August 23, 2021 5:57 PM
> >> To: Xueming(Steven) Li <xuemingl@nvidia.com>
> >> Cc: dev@dpdk.org; Maxime Coquelin <maxime.coquelin@redhat.com>; Chenbo Xia
> <chenbo.xia@intel.com>
> >> Subject: Re: [dpdk-dev] [PATCH] net/virtio: wait device ready in device
> reset
> >>
> >> On 8/23/21 9:39 AM, Xueming Li wrote:
> >>> According to virtio spec, the device MUST reset when 0 is written to
> >>> device_status, and present a 0 in device_status once that is done.
> >>>
> >>> This patch adds the missing part of waiting status 0 in reset function.
> >>>
> >>> Signed-off-by: Xueming Li <xuemingl@nvidia.com>
> >>> ---
> >>>  drivers/net/virtio/virtio.c | 7 +++++--
> >>>  1 file changed, 5 insertions(+), 2 deletions(-)
> >>>
> >>> diff --git a/drivers/net/virtio/virtio.c b/drivers/net/virtio/virtio.c
> >>> index 7e1e77797f..f003f612d6 100644
> >>> --- a/drivers/net/virtio/virtio.c
> >>> +++ b/drivers/net/virtio/virtio.c
> >>> @@ -3,6 +3,8 @@
> >>>   * Copyright(c) 2020 Red Hat, Inc.
> >>>   */
> >>>
> >>> +#include <unistd.h>
> >>> +
> >>>  #include "virtio.h"
> >>>
> >>>  uint64_t
> >>> @@ -39,8 +41,9 @@ void
> >>>  virtio_reset(struct virtio_hw *hw)
> >>>  {
> >>>  	VIRTIO_OPS(hw)->set_status(hw, VIRTIO_CONFIG_STATUS_RESET);
> >>> -	/* flush status write */
> >>> -	VIRTIO_OPS(hw)->get_status(hw);
> >>> +	/* Flush status write and wait device ready. */
> >>> +	while (VIRTIO_OPS(hw)->get_status(hw) != VIRTIO_CONFIG_STATUS_RESET)
> >>> +		usleep(1000L);
> >>
> >> Don't we need a protection against forever loop here?
> >
> > Good question, ideally we need, kernel driver function vp_reset() seems to
> have same issue.
> 
> Yes, I've seen it.
> 
> > How about leaving an error message before return?
> 
> @Maxime, @Chenbo, what do you think?

I would vote for waiting for some time before return rather than forever loop
and error message is needed.

My understanding is for kernel, it's fine to sleep forever as kernel could schedule
it but for DPDK, it will lead to main lcore unable to do other things but sleep
forever. Meanwhile, users will see the app stuck but don't know what's wrong here.

Thanks,
Chenbo

 

[dpdk-dev] [PATCH v1] net/virtio: wait device ready during reset

[Xueming Li]

According to virtio spec, the device MUST reset when 0 is written to
device_status, and present 0 in device_status once reset is done.

This patch waits status value to be 0 during reset operation, if
timeout in 3 seconds, log and continue.

Signed-off-by: Xueming Li <xuemingl@nvidia.com>
Cc: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
---
 drivers/net/virtio/virtio.c | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/drivers/net/virtio/virtio.c b/drivers/net/virtio/virtio.c
index 7e1e77797f..f865b27b65 100644
--- a/drivers/net/virtio/virtio.c
+++ b/drivers/net/virtio/virtio.c
@@ -3,7 +3,10 @@
  * Copyright(c) 2020 Red Hat, Inc.
  */
 
+#include <unistd.h>
+
 #include "virtio.h"
+#include "virtio_logs.h"
 
 uint64_t
 virtio_negotiate_features(struct virtio_hw *hw, uint64_t host_features)
@@ -38,9 +41,17 @@ virtio_write_dev_config(struct virtio_hw *hw, size_t offset,
 void
 virtio_reset(struct virtio_hw *hw)
 {
+	uint32_t retry = 0;
+
 	VIRTIO_OPS(hw)->set_status(hw, VIRTIO_CONFIG_STATUS_RESET);
-	/* flush status write */
-	VIRTIO_OPS(hw)->get_status(hw);
+	/* Flush status write and wait device ready max 3 seconds. */
+	while (VIRTIO_OPS(hw)->get_status(hw) != VIRTIO_CONFIG_STATUS_RESET) {
+		if (retry++ > 3000) {
+			PMD_INIT_LOG(WARNING, "device reset timeout");
+			break;
+		}
+		usleep(1000L);
+	}
 }
 
 void
-- 
2.33.0

Re: [dpdk-dev] [PATCH] net/virtio: wait device ready in device reset

[Xueming(Steven) Li]

On Thu, 2021-08-26 at 07:15 +0000, Xia, Chenbo wrote:
> Hi Adrew & Xueming,
> 
> > -----Original Message-----
> > From: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
> > Sent: Tuesday, August 24, 2021 11:41 PM
> > To: Xueming(Steven) Li <xuemingl@nvidia.com>
> > Cc: dev@dpdk.org; Maxime Coquelin <maxime.coquelin@redhat.com>; Xia, Chenbo
> > <chenbo.xia@intel.com>
> > Subject: Re: [dpdk-dev] [PATCH] net/virtio: wait device ready in device reset
> > 
> > On 8/23/21 4:54 PM, Xueming(Steven) Li wrote:
> > > 
> > > 
> > > > -----Original Message-----
> > > > From: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
> > > > Sent: Monday, August 23, 2021 5:57 PM
> > > > To: Xueming(Steven) Li <xuemingl@nvidia.com>
> > > > Cc: dev@dpdk.org; Maxime Coquelin <maxime.coquelin@redhat.com>; Chenbo Xia
> > <chenbo.xia@intel.com>
> > > > Subject: Re: [dpdk-dev] [PATCH] net/virtio: wait device ready in device
> > reset
> > > > 
> > > > On 8/23/21 9:39 AM, Xueming Li wrote:
> > > > > According to virtio spec, the device MUST reset when 0 is written to
> > > > > device_status, and present a 0 in device_status once that is done.
> > > > > 
> > > > > This patch adds the missing part of waiting status 0 in reset function.
> > > > > 
> > > > > Signed-off-by: Xueming Li <xuemingl@nvidia.com>
> > > > > ---
> > > > >  drivers/net/virtio/virtio.c | 7 +++++--
> > > > >  1 file changed, 5 insertions(+), 2 deletions(-)
> > > > > 
> > > > > diff --git a/drivers/net/virtio/virtio.c b/drivers/net/virtio/virtio.c
> > > > > index 7e1e77797f..f003f612d6 100644
> > > > > --- a/drivers/net/virtio/virtio.c
> > > > > +++ b/drivers/net/virtio/virtio.c
> > > > > @@ -3,6 +3,8 @@
> > > > >   * Copyright(c) 2020 Red Hat, Inc.
> > > > >   */
> > > > > 
> > > > > +#include <unistd.h>
> > > > > +
> > > > >  #include "virtio.h"
> > > > > 
> > > > >  uint64_t
> > > > > @@ -39,8 +41,9 @@ void
> > > > >  virtio_reset(struct virtio_hw *hw)
> > > > >  {
> > > > >  	VIRTIO_OPS(hw)->set_status(hw, VIRTIO_CONFIG_STATUS_RESET);
> > > > > -	/* flush status write */
> > > > > -	VIRTIO_OPS(hw)->get_status(hw);
> > > > > +	/* Flush status write and wait device ready. */
> > > > > +	while (VIRTIO_OPS(hw)->get_status(hw) != VIRTIO_CONFIG_STATUS_RESET)
> > > > > +		usleep(1000L);
> > > > 
> > > > Don't we need a protection against forever loop here?
> > > 
> > > Good question, ideally we need, kernel driver function vp_reset() seems to
> > have same issue.
> > 
> > Yes, I've seen it.
> > 
> > > How about leaving an error message before return?
> > 
> > @Maxime, @Chenbo, what do you think?
> 
> I would vote for waiting for some time before return rather than forever loop
> and error message is needed.
> 
> My understanding is for kernel, it's fine to sleep forever as kernel could schedule
> it but for DPDK, it will lead to main lcore unable to do other things but sleep
> forever. Meanwhile, users will see the app stuck but don't know what's wrong here.
> 
> Thanks,
> Chenbo
> 

Hi all, thanks for you sugestion, new version posted:
https://mails.dpdk.org/archives/dev/2021-September/219866.html

>  

Re: [dpdk-dev] [PATCH v1] net/virtio: wait device ready during reset

[Andrew Rybchenko]

On 9/15/21 12:21 PM, Xueming Li wrote:
> According to virtio spec, the device MUST reset when 0 is written to
> device_status, and present 0 in device_status once reset is done.
> 
> This patch waits status value to be 0 during reset operation, if
> timeout in 3 seconds, log and continue.

I have no strong opinion on timeout.

> 
> Signed-off-by: Xueming Li <xuemingl@nvidia.com>
> Cc: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
> ---
>  drivers/net/virtio/virtio.c | 15 +++++++++++++--
>  1 file changed, 13 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/virtio/virtio.c b/drivers/net/virtio/virtio.c
> index 7e1e77797f..f865b27b65 100644
> --- a/drivers/net/virtio/virtio.c
> +++ b/drivers/net/virtio/virtio.c
> @@ -3,7 +3,10 @@
>   * Copyright(c) 2020 Red Hat, Inc.
>   */
>  
> +#include <unistd.h>
> +
>  #include "virtio.h"
> +#include "virtio_logs.h"
>  
>  uint64_t
>  virtio_negotiate_features(struct virtio_hw *hw, uint64_t host_features)
> @@ -38,9 +41,17 @@ virtio_write_dev_config(struct virtio_hw *hw, size_t offset,
>  void
>  virtio_reset(struct virtio_hw *hw)
>  {
> +	uint32_t retry = 0;
> +
>  	VIRTIO_OPS(hw)->set_status(hw, VIRTIO_CONFIG_STATUS_RESET);
> -	/* flush status write */
> -	VIRTIO_OPS(hw)->get_status(hw);
> +	/* Flush status write and wait device ready max 3 seconds. */
> +	while (VIRTIO_OPS(hw)->get_status(hw) != VIRTIO_CONFIG_STATUS_RESET) {
> +		if (retry++ > 3000) {
> +			PMD_INIT_LOG(WARNING, "device reset timeout");

I think it would be very useful to log ethdev port ID here.

> +			break;
> +		}
> +		usleep(1000L);
> +	}
>  }
>  
>  void
> 

[dpdk-dev] [PATCH v2] net/virtio: wait device ready during reset

[Xueming Li]

According to virtio spec, the device MUST reset when 0 is written to
device_status, and present 0 in device_status once reset is done.

This patch waits status value to be 0 during reset operation, if
timeout in 3 seconds, log and continue.

Signed-off-by: Xueming Li <xuemingl@nvidia.com>
Cc: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
---
 drivers/net/virtio/virtio.c | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/drivers/net/virtio/virtio.c b/drivers/net/virtio/virtio.c
index 7e1e77797f..d9e642f412 100644
--- a/drivers/net/virtio/virtio.c
+++ b/drivers/net/virtio/virtio.c
@@ -3,7 +3,10 @@
  * Copyright(c) 2020 Red Hat, Inc.
  */
 
+#include <unistd.h>
+
 #include "virtio.h"
+#include "virtio_logs.h"
 
 uint64_t
 virtio_negotiate_features(struct virtio_hw *hw, uint64_t host_features)
@@ -38,9 +41,17 @@ virtio_write_dev_config(struct virtio_hw *hw, size_t offset,
 void
 virtio_reset(struct virtio_hw *hw)
 {
+	uint32_t retry = 0;
+
 	VIRTIO_OPS(hw)->set_status(hw, VIRTIO_CONFIG_STATUS_RESET);
-	/* flush status write */
-	VIRTIO_OPS(hw)->get_status(hw);
+	/* Flush status write and wait device ready max 3 seconds. */
+	while (VIRTIO_OPS(hw)->get_status(hw) != VIRTIO_CONFIG_STATUS_RESET) {
+		if (retry++ > 3000) {
+			PMD_INIT_LOG(WARNING, "port %u device reset timeout", hw->port_id);
+			break;
+		}
+		usleep(1000L);
+	}
 }
 
 void
-- 
2.33.0

Re: [dpdk-dev] [PATCH v1] net/virtio: wait device ready during reset

[Xueming(Steven) Li]

On Wed, 2021-09-15 at 12:27 +0300, Andrew Rybchenko wrote:
> On 9/15/21 12:21 PM, Xueming Li wrote:
> > According to virtio spec, the device MUST reset when 0 is written to
> > device_status, and present 0 in device_status once reset is done.
> > 
> > This patch waits status value to be 0 during reset operation, if
> > timeout in 3 seconds, log and continue.
> 
> I have no strong opinion on timeout.
> 
> > 
> > Signed-off-by: Xueming Li <xuemingl@nvidia.com>
> > Cc: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
> > ---
> >  drivers/net/virtio/virtio.c | 15 +++++++++++++--
> >  1 file changed, 13 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/net/virtio/virtio.c b/drivers/net/virtio/virtio.c
> > index 7e1e77797f..f865b27b65 100644
> > --- a/drivers/net/virtio/virtio.c
> > +++ b/drivers/net/virtio/virtio.c
> > @@ -3,7 +3,10 @@
> >   * Copyright(c) 2020 Red Hat, Inc.
> >   */
> >  
> > +#include <unistd.h>
> > +
> >  #include "virtio.h"
> > +#include "virtio_logs.h"
> >  
> >  uint64_t
> >  virtio_negotiate_features(struct virtio_hw *hw, uint64_t host_features)
> > @@ -38,9 +41,17 @@ virtio_write_dev_config(struct virtio_hw *hw, size_t offset,
> >  void
> >  virtio_reset(struct virtio_hw *hw)
> >  {
> > +	uint32_t retry = 0;
> > +
> >  	VIRTIO_OPS(hw)->set_status(hw, VIRTIO_CONFIG_STATUS_RESET);
> > -	/* flush status write */
> > -	VIRTIO_OPS(hw)->get_status(hw);
> > +	/* Flush status write and wait device ready max 3 seconds. */
> > +	while (VIRTIO_OPS(hw)->get_status(hw) != VIRTIO_CONFIG_STATUS_RESET) {
> > +		if (retry++ > 3000) {
> > +			PMD_INIT_LOG(WARNING, "device reset timeout");
> 
> I think it would be very useful to log ethdev port ID here.

Good suggesiton, v2 sent.

> 
> > +			break;
> > +		}
> > +		usleep(1000L);
> > +	}
> >  }
> >  
> >  void
> > 
> 

Re: [dpdk-dev] [PATCH v2] net/virtio: wait device ready during reset

[Andrew Rybchenko]

On 9/15/21 1:12 PM, Xueming Li wrote:
> According to virtio spec, the device MUST reset when 0 is written to
> device_status, and present 0 in device_status once reset is done.
> 
> This patch waits status value to be 0 during reset operation, if
> timeout in 3 seconds, log and continue.
> 
> Signed-off-by: Xueming Li <xuemingl@nvidia.com>
> Cc: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>

Acked-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>

Re: [dpdk-dev] [PATCH v2] net/virtio: wait device ready during reset

[Xia, Chenbo]

> -----Original Message-----
> From: Xueming Li <xuemingl@nvidia.com>
> Sent: Wednesday, September 15, 2021 6:12 PM
> To: dev@dpdk.org
> Cc: xuemingl@nvidia.com; Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>;
> Maxime Coquelin <maxime.coquelin@redhat.com>; Xia, Chenbo
> <chenbo.xia@intel.com>
> Subject: [PATCH v2] net/virtio: wait device ready during reset
> 
> According to virtio spec, the device MUST reset when 0 is written to
> device_status, and present 0 in device_status once reset is done.
> 
> This patch waits status value to be 0 during reset operation, if
> timeout in 3 seconds, log and continue.
> 
> Signed-off-by: Xueming Li <xuemingl@nvidia.com>
> Cc: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
> --
> 2.33.0

Reviewed-by: Chenbo Xia <chenbo.xia@intel.com>

Re: [dpdk-dev] [PATCH v2] net/virtio: wait device ready during reset

[Maxime Coquelin]

On 9/15/21 12:12, Xueming Li wrote:
> According to virtio spec, the device MUST reset when 0 is written to
> device_status, and present 0 in device_status once reset is done.
> 
> This patch waits status value to be 0 during reset operation, if
> timeout in 3 seconds, log and continue.
> 
> Signed-off-by: Xueming Li <xuemingl@nvidia.com>
> Cc: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
> ---
>   drivers/net/virtio/virtio.c | 15 +++++++++++++--
>   1 file changed, 13 insertions(+), 2 deletions(-)
> 

Applied to dpdk-next-virtio/main.

Thanks,
Maxime