[PATCH v3] hv_netvsc: Allocate rx indirection table size dynamically

[PATCH v3] hv_netvsc: Allocate rx indirection table size dynamically

[Shradha Gupta]

Allocate the size of rx indirection table dynamically in netvsc
from the value of size provided by OID_GEN_RECEIVE_SCALE_CAPABILITIES
query instead of using a constant value of ITAB_NUM.

Signed-off-by: Shradha Gupta <shradhagupta@linux.microsoft.com>
Tested-on: Ubuntu22 (azure VM, SKU size: Standard_F72s_v2)
Testcases:
1. ethtool -x eth0 output
2. LISA testcase:PERF-NETWORK-TCP-THROUGHPUT-MULTICONNECTION-NTTTCP-Synthetic
3. LISA testcase:PERF-NETWORK-TCP-THROUGHPUT-MULTICONNECTION-NTTTCP-SRIOV

---
Changes in v3:
 * Changed the data type of rx_table_sz to u32
 * Moved the rx indirection table free to rndis_filter_device_remove()
 * Device add will fail with error if not enough memory is available
 * Changed kzmalloc to kcalloc as suggested in checkpatch script
 * Removed redundant log if memory allocation failed.
---
 drivers/net/hyperv/hyperv_net.h   |  5 ++++-
 drivers/net/hyperv/netvsc_drv.c   | 10 ++++++----
 drivers/net/hyperv/rndis_filter.c | 27 +++++++++++++++++++++++----
 3 files changed, 33 insertions(+), 9 deletions(-)

diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index dd5919ec408b..c40868f287a9 100644
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -74,6 +74,7 @@ struct ndis_recv_scale_cap { /* NDIS_RECEIVE_SCALE_CAPABILITIES */
 #define NDIS_RSS_HASH_SECRET_KEY_MAX_SIZE_REVISION_2   40
 
 #define ITAB_NUM 128
+#define ITAB_NUM_MAX 256
 
 struct ndis_recv_scale_param { /* NDIS_RECEIVE_SCALE_PARAMETERS */
 	struct ndis_obj_header hdr;
@@ -1034,7 +1035,9 @@ struct net_device_context {
 
 	u32 tx_table[VRSS_SEND_TAB_SIZE];
 
-	u16 rx_table[ITAB_NUM];
+	u16 *rx_table;
+
+	u32 rx_table_sz;
 
 	/* Ethtool settings */
 	u8 duplex;
diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 0103ff914024..3ba3c8fb28a5 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -1747,7 +1747,9 @@ static u32 netvsc_get_rxfh_key_size(struct net_device *dev)
 
 static u32 netvsc_rss_indir_size(struct net_device *dev)
 {
-	return ITAB_NUM;
+	struct net_device_context *ndc = netdev_priv(dev);
+
+	return ndc->rx_table_sz;
 }
 
 static int netvsc_get_rxfh(struct net_device *dev, u32 *indir, u8 *key,
@@ -1766,7 +1768,7 @@ static int netvsc_get_rxfh(struct net_device *dev, u32 *indir, u8 *key,
 
 	rndis_dev = ndev->extension;
 	if (indir) {
-		for (i = 0; i < ITAB_NUM; i++)
+		for (i = 0; i < ndc->rx_table_sz; i++)
 			indir[i] = ndc->rx_table[i];
 	}
 
@@ -1792,11 +1794,11 @@ static int netvsc_set_rxfh(struct net_device *dev, const u32 *indir,
 
 	rndis_dev = ndev->extension;
 	if (indir) {
-		for (i = 0; i < ITAB_NUM; i++)
+		for (i = 0; i < ndc->rx_table_sz; i++)
 			if (indir[i] >= ndev->num_chn)
 				return -EINVAL;
 
-		for (i = 0; i < ITAB_NUM; i++)
+		for (i = 0; i < ndc->rx_table_sz; i++)
 			ndc->rx_table[i] = indir[i];
 	}
 
diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
index eea777ec2541..dc7b9b326690 100644
--- a/drivers/net/hyperv/rndis_filter.c
+++ b/drivers/net/hyperv/rndis_filter.c
@@ -21,6 +21,7 @@
 #include <linux/rtnetlink.h>
 #include <linux/ucs2_string.h>
 #include <linux/string.h>
+#include <linux/slab.h>
 
 #include "hyperv_net.h"
 #include "netvsc_trace.h"
@@ -927,7 +928,7 @@ static int rndis_set_rss_param_msg(struct rndis_device *rdev,
 	struct rndis_set_request *set;
 	struct rndis_set_complete *set_complete;
 	u32 extlen = sizeof(struct ndis_recv_scale_param) +
-		     4 * ITAB_NUM + NETVSC_HASH_KEYLEN;
+		     4 * ndc->rx_table_sz + NETVSC_HASH_KEYLEN;
 	struct ndis_recv_scale_param *rssp;
 	u32 *itab;
 	u8 *keyp;
@@ -953,7 +954,7 @@ static int rndis_set_rss_param_msg(struct rndis_device *rdev,
 	rssp->hashinfo = NDIS_HASH_FUNC_TOEPLITZ | NDIS_HASH_IPV4 |
 			 NDIS_HASH_TCP_IPV4 | NDIS_HASH_IPV6 |
 			 NDIS_HASH_TCP_IPV6;
-	rssp->indirect_tabsize = 4*ITAB_NUM;
+	rssp->indirect_tabsize = 4 * ndc->rx_table_sz;
 	rssp->indirect_taboffset = sizeof(struct ndis_recv_scale_param);
 	rssp->hashkey_size = NETVSC_HASH_KEYLEN;
 	rssp->hashkey_offset = rssp->indirect_taboffset +
@@ -961,7 +962,7 @@ static int rndis_set_rss_param_msg(struct rndis_device *rdev,
 
 	/* Set indirection table entries */
 	itab = (u32 *)(rssp + 1);
-	for (i = 0; i < ITAB_NUM; i++)
+	for (i = 0; i < ndc->rx_table_sz; i++)
 		itab[i] = ndc->rx_table[i];
 
 	/* Set hask key values */
@@ -1548,6 +1549,17 @@ struct netvsc_device *rndis_filter_device_add(struct hv_device *dev,
 	if (ret || rsscap.num_recv_que < 2)
 		goto out;
 
+	if (rsscap.num_indirect_tabent &&
+	    rsscap.num_indirect_tabent <= ITAB_NUM_MAX)
+		ndc->rx_table_sz = rsscap.num_indirect_tabent;
+	else
+		ndc->rx_table_sz = ITAB_NUM;
+
+	ndc->rx_table = kcalloc(ndc->rx_table_sz, sizeof(u16),
+				GFP_KERNEL);
+	if (!ndc->rx_table)
+		goto err_dev_remv;
+
 	/* This guarantees that num_possible_rss_qs <= num_online_cpus */
 	num_possible_rss_qs = min_t(u32, num_online_cpus(),
 				    rsscap.num_recv_que);
@@ -1558,7 +1570,7 @@ struct netvsc_device *rndis_filter_device_add(struct hv_device *dev,
 	net_device->num_chn = min(net_device->max_chn, device_info->num_chn);
 
 	if (!netif_is_rxfh_configured(net)) {
-		for (i = 0; i < ITAB_NUM; i++)
+		for (i = 0; i < ndc->rx_table_sz; i++)
 			ndc->rx_table[i] = ethtool_rxfh_indir_default(
 						i, net_device->num_chn);
 	}
@@ -1596,11 +1608,18 @@ void rndis_filter_device_remove(struct hv_device *dev,
 				struct netvsc_device *net_dev)
 {
 	struct rndis_device *rndis_dev = net_dev->extension;
+	struct net_device *net = hv_get_drvdata(dev);
+	struct net_device_context *ndc = netdev_priv(net);
 
 	/* Halt and release the rndis device */
 	rndis_filter_halt_device(net_dev, rndis_dev);
 
 	netvsc_device_remove(dev);
+
+	ndc->rx_table_sz = 0;
+	kfree(ndc->rx_table);
+	ndc->rx_table = NULL;
+
 }
 
 int rndis_filter_open(struct netvsc_device *nvdev)
-- 
2.34.1

Re: [PATCH v3] hv_netvsc: Allocate rx indirection table size dynamically

[Simon Horman]

On Thu, May 25, 2023 at 11:02:29PM -0700, Shradha Gupta wrote:
> Allocate the size of rx indirection table dynamically in netvsc
> from the value of size provided by OID_GEN_RECEIVE_SCALE_CAPABILITIES
> query instead of using a constant value of ITAB_NUM.
> 
> Signed-off-by: Shradha Gupta <shradhagupta@linux.microsoft.com>

> @@ -1548,6 +1549,17 @@ struct netvsc_device *rndis_filter_device_add(struct hv_device *dev,
>  	if (ret || rsscap.num_recv_que < 2)
>  		goto out;
>  
> +	if (rsscap.num_indirect_tabent &&
> +	    rsscap.num_indirect_tabent <= ITAB_NUM_MAX)
> +		ndc->rx_table_sz = rsscap.num_indirect_tabent;
> +	else
> +		ndc->rx_table_sz = ITAB_NUM;
> +
> +	ndc->rx_table = kcalloc(ndc->rx_table_sz, sizeof(u16),
> +				GFP_KERNEL);

nit: the above could fit on a single line.

> +	if (!ndc->rx_table)

I think you need to set ret to an error value here,
as err_dev_remv will call return ERR_PTR(ret).

> +		goto err_dev_remv;
> +
>  	/* This guarantees that num_possible_rss_qs <= num_online_cpus */
>  	num_possible_rss_qs = min_t(u32, num_online_cpus(),
>  				    rsscap.num_recv_que);
> @@ -1558,7 +1570,7 @@ struct netvsc_device *rndis_filter_device_add(struct hv_device *dev,
>  	net_device->num_chn = min(net_device->max_chn, device_info->num_chn);
>  
>  	if (!netif_is_rxfh_configured(net)) {
> -		for (i = 0; i < ITAB_NUM; i++)
> +		for (i = 0; i < ndc->rx_table_sz; i++)
>  			ndc->rx_table[i] = ethtool_rxfh_indir_default(
>  						i, net_device->num_chn);
>  	}
> @@ -1596,11 +1608,18 @@ void rndis_filter_device_remove(struct hv_device *dev,
>  				struct netvsc_device *net_dev)
>  {
>  	struct rndis_device *rndis_dev = net_dev->extension;
> +	struct net_device *net = hv_get_drvdata(dev);
> +	struct net_device_context *ndc = netdev_priv(net);

nit: Please use reverse xmas tree order - longest line to shortest -
     for local variable declaration sin networking code.

	struct rndis_device *rndis_dev = net_dev->extension;
	struct net_device *net = hv_get_drvdata(dev);
	struct net_device_context *ndc;

	ndc = netdev_priv(net);

>  
>  	/* Halt and release the rndis device */
>  	rndis_filter_halt_device(net_dev, rndis_dev);
>  
>  	netvsc_device_remove(dev);
> +
> +	ndc->rx_table_sz = 0;
> +	kfree(ndc->rx_table);
> +	ndc->rx_table = NULL;
> +
>  }
>  
>  int rndis_filter_open(struct netvsc_device *nvdev)

-- 
pw-bot: cr

Re: [PATCH v3] hv_netvsc: Allocate rx indirection table size dynamically

[Praveen Kumar]

On 5/26/2023 11:32 AM, Shradha Gupta wrote:
> Allocate the size of rx indirection table dynamically in netvsc
> from the value of size provided by OID_GEN_RECEIVE_SCALE_CAPABILITIES
> query instead of using a constant value of ITAB_NUM.
> 
> Signed-off-by: Shradha Gupta <shradhagupta@linux.microsoft.com>
> Tested-on: Ubuntu22 (azure VM, SKU size: Standard_F72s_v2)
> Testcases:
> 1. ethtool -x eth0 output
> 2. LISA testcase:PERF-NETWORK-TCP-THROUGHPUT-MULTICONNECTION-NTTTCP-Synthetic
> 3. LISA testcase:PERF-NETWORK-TCP-THROUGHPUT-MULTICONNECTION-NTTTCP-SRIOV
> 
> ---
> Changes in v3:
>  * Changed the data type of rx_table_sz to u32
>  * Moved the rx indirection table free to rndis_filter_device_remove()
>  * Device add will fail with error if not enough memory is available
>  * Changed kzmalloc to kcalloc as suggested in checkpatch script
>  * Removed redundant log if memory allocation failed.
> ---
>  drivers/net/hyperv/hyperv_net.h   |  5 ++++-
>  drivers/net/hyperv/netvsc_drv.c   | 10 ++++++----
>  drivers/net/hyperv/rndis_filter.c | 27 +++++++++++++++++++++++----
>  3 files changed, 33 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
> index dd5919ec408b..c40868f287a9 100644
> --- a/drivers/net/hyperv/hyperv_net.h
> +++ b/drivers/net/hyperv/hyperv_net.h
> @@ -74,6 +74,7 @@ struct ndis_recv_scale_cap { /* NDIS_RECEIVE_SCALE_CAPABILITIES */
>  #define NDIS_RSS_HASH_SECRET_KEY_MAX_SIZE_REVISION_2   40
>  
>  #define ITAB_NUM 128
> +#define ITAB_NUM_MAX 256
>  
>  struct ndis_recv_scale_param { /* NDIS_RECEIVE_SCALE_PARAMETERS */
>  	struct ndis_obj_header hdr;
> @@ -1034,7 +1035,9 @@ struct net_device_context {
>  
>  	u32 tx_table[VRSS_SEND_TAB_SIZE];
>  
> -	u16 rx_table[ITAB_NUM];
> +	u16 *rx_table;
> +
> +	u32 rx_table_sz;
>  
>  	/* Ethtool settings */
>  	u8 duplex;
> diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
> index 0103ff914024..3ba3c8fb28a5 100644
> --- a/drivers/net/hyperv/netvsc_drv.c
> +++ b/drivers/net/hyperv/netvsc_drv.c
> @@ -1747,7 +1747,9 @@ static u32 netvsc_get_rxfh_key_size(struct net_device *dev)
>  
>  static u32 netvsc_rss_indir_size(struct net_device *dev)
>  {
> -	return ITAB_NUM;
> +	struct net_device_context *ndc = netdev_priv(dev);
> +
> +	return ndc->rx_table_sz;
>  }
>  
>  static int netvsc_get_rxfh(struct net_device *dev, u32 *indir, u8 *key,
> @@ -1766,7 +1768,7 @@ static int netvsc_get_rxfh(struct net_device *dev, u32 *indir, u8 *key,
>  
>  	rndis_dev = ndev->extension;
>  	if (indir) {
> -		for (i = 0; i < ITAB_NUM; i++)
> +		for (i = 0; i < ndc->rx_table_sz; i++)
>  			indir[i] = ndc->rx_table[i];
>  	}
>  
> @@ -1792,11 +1794,11 @@ static int netvsc_set_rxfh(struct net_device *dev, const u32 *indir,
>  
>  	rndis_dev = ndev->extension;
>  	if (indir) {
> -		for (i = 0; i < ITAB_NUM; i++)
> +		for (i = 0; i < ndc->rx_table_sz; i++)
>  			if (indir[i] >= ndev->num_chn)
>  				return -EINVAL;
>  
> -		for (i = 0; i < ITAB_NUM; i++)
> +		for (i = 0; i < ndc->rx_table_sz; i++)
>  			ndc->rx_table[i] = indir[i];
>  	}
>  
> diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
> index eea777ec2541..dc7b9b326690 100644
> --- a/drivers/net/hyperv/rndis_filter.c
> +++ b/drivers/net/hyperv/rndis_filter.c
> @@ -21,6 +21,7 @@
>  #include <linux/rtnetlink.h>
>  #include <linux/ucs2_string.h>
>  #include <linux/string.h>
> +#include <linux/slab.h>
>  
>  #include "hyperv_net.h"
>  #include "netvsc_trace.h"
> @@ -927,7 +928,7 @@ static int rndis_set_rss_param_msg(struct rndis_device *rdev,
>  	struct rndis_set_request *set;
>  	struct rndis_set_complete *set_complete;
>  	u32 extlen = sizeof(struct ndis_recv_scale_param) +
> -		     4 * ITAB_NUM + NETVSC_HASH_KEYLEN;
> +		     4 * ndc->rx_table_sz + NETVSC_HASH_KEYLEN;
>  	struct ndis_recv_scale_param *rssp;
>  	u32 *itab;
>  	u8 *keyp;
> @@ -953,7 +954,7 @@ static int rndis_set_rss_param_msg(struct rndis_device *rdev,
>  	rssp->hashinfo = NDIS_HASH_FUNC_TOEPLITZ | NDIS_HASH_IPV4 |
>  			 NDIS_HASH_TCP_IPV4 | NDIS_HASH_IPV6 |
>  			 NDIS_HASH_TCP_IPV6;
> -	rssp->indirect_tabsize = 4*ITAB_NUM;
> +	rssp->indirect_tabsize = 4 * ndc->rx_table_sz;
>  	rssp->indirect_taboffset = sizeof(struct ndis_recv_scale_param);
>  	rssp->hashkey_size = NETVSC_HASH_KEYLEN;
>  	rssp->hashkey_offset = rssp->indirect_taboffset +
> @@ -961,7 +962,7 @@ static int rndis_set_rss_param_msg(struct rndis_device *rdev,
>  
>  	/* Set indirection table entries */
>  	itab = (u32 *)(rssp + 1);
> -	for (i = 0; i < ITAB_NUM; i++)
> +	for (i = 0; i < ndc->rx_table_sz; i++)
>  		itab[i] = ndc->rx_table[i];
>  
>  	/* Set hask key values */
> @@ -1548,6 +1549,17 @@ struct netvsc_device *rndis_filter_device_add(struct hv_device *dev,
>  	if (ret || rsscap.num_recv_que < 2)
>  		goto out;
>  
> +	if (rsscap.num_indirect_tabent &&
> +	    rsscap.num_indirect_tabent <= ITAB_NUM_MAX)
> +		ndc->rx_table_sz = rsscap.num_indirect_tabent;
> +	else
> +		ndc->rx_table_sz = ITAB_NUM;
> +
> +	ndc->rx_table = kcalloc(ndc->rx_table_sz, sizeof(u16),
> +				GFP_KERNEL);
> +	if (!ndc->rx_table)
> +		goto err_dev_remv;
> +
>  	/* This guarantees that num_possible_rss_qs <= num_online_cpus */
>  	num_possible_rss_qs = min_t(u32, num_online_cpus(),
>  				    rsscap.num_recv_que);
> @@ -1558,7 +1570,7 @@ struct netvsc_device *rndis_filter_device_add(struct hv_device *dev,
>  	net_device->num_chn = min(net_device->max_chn, device_info->num_chn);
>  
>  	if (!netif_is_rxfh_configured(net)) {
> -		for (i = 0; i < ITAB_NUM; i++)
> +		for (i = 0; i < ndc->rx_table_sz; i++)
>  			ndc->rx_table[i] = ethtool_rxfh_indir_default(
>  						i, net_device->num_chn);
>  	}
> @@ -1596,11 +1608,18 @@ void rndis_filter_device_remove(struct hv_device *dev,
>  				struct netvsc_device *net_dev)
>  {
>  	struct rndis_device *rndis_dev = net_dev->extension;
> +	struct net_device *net = hv_get_drvdata(dev);
> +	struct net_device_context *ndc = netdev_priv(net);
>  
>  	/* Halt and release the rndis device */
>  	rndis_filter_halt_device(net_dev, rndis_dev);
>  
>  	netvsc_device_remove(dev);

Shouldn't the netvsc_device_remove be called post table cleanup ? or better, the cleanup should happen as part of netvsc_device_remove operation ? This looks a bug to me as with remove operation, we already cleaned up the device and the association between context and device is removed.
> +
> +	ndc->rx_table_sz = 0;
> +	kfree(ndc->rx_table);
> +	ndc->rx_table = NULL;
> +
>  }
>  
>  int rndis_filter_open(struct netvsc_device *nvdev)

Re: [PATCH v3] hv_netvsc: Allocate rx indirection table size dynamically

[Shradha Gupta]

On Mon, May 29, 2023 at 03:09:49PM +0530, Praveen Kumar wrote:
> On 5/26/2023 11:32 AM, Shradha Gupta wrote:
> > Allocate the size of rx indirection table dynamically in netvsc
> > from the value of size provided by OID_GEN_RECEIVE_SCALE_CAPABILITIES
> > query instead of using a constant value of ITAB_NUM.
> > 
> > Signed-off-by: Shradha Gupta <shradhagupta@linux.microsoft.com>
> > Tested-on: Ubuntu22 (azure VM, SKU size: Standard_F72s_v2)
> > Testcases:
> > 1. ethtool -x eth0 output
> > 2. LISA testcase:PERF-NETWORK-TCP-THROUGHPUT-MULTICONNECTION-NTTTCP-Synthetic
> > 3. LISA testcase:PERF-NETWORK-TCP-THROUGHPUT-MULTICONNECTION-NTTTCP-SRIOV
> > 
> > ---
> > Changes in v3:
> >  * Changed the data type of rx_table_sz to u32
> >  * Moved the rx indirection table free to rndis_filter_device_remove()
> >  * Device add will fail with error if not enough memory is available
> >  * Changed kzmalloc to kcalloc as suggested in checkpatch script
> >  * Removed redundant log if memory allocation failed.
> > ---
> >  drivers/net/hyperv/hyperv_net.h   |  5 ++++-
> >  drivers/net/hyperv/netvsc_drv.c   | 10 ++++++----
> >  drivers/net/hyperv/rndis_filter.c | 27 +++++++++++++++++++++++----
> >  3 files changed, 33 insertions(+), 9 deletions(-)
> > 
> > diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
> > index dd5919ec408b..c40868f287a9 100644
> > --- a/drivers/net/hyperv/hyperv_net.h
> > +++ b/drivers/net/hyperv/hyperv_net.h
> > @@ -74,6 +74,7 @@ struct ndis_recv_scale_cap { /* NDIS_RECEIVE_SCALE_CAPABILITIES */
> >  #define NDIS_RSS_HASH_SECRET_KEY_MAX_SIZE_REVISION_2   40
> >  
> >  #define ITAB_NUM 128
> > +#define ITAB_NUM_MAX 256
> >  
> >  struct ndis_recv_scale_param { /* NDIS_RECEIVE_SCALE_PARAMETERS */
> >  	struct ndis_obj_header hdr;
> > @@ -1034,7 +1035,9 @@ struct net_device_context {
> >  
> >  	u32 tx_table[VRSS_SEND_TAB_SIZE];
> >  
> > -	u16 rx_table[ITAB_NUM];
> > +	u16 *rx_table;
> > +
> > +	u32 rx_table_sz;
> >  
> >  	/* Ethtool settings */
> >  	u8 duplex;
> > diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
> > index 0103ff914024..3ba3c8fb28a5 100644
> > --- a/drivers/net/hyperv/netvsc_drv.c
> > +++ b/drivers/net/hyperv/netvsc_drv.c
> > @@ -1747,7 +1747,9 @@ static u32 netvsc_get_rxfh_key_size(struct net_device *dev)
> >  
> >  static u32 netvsc_rss_indir_size(struct net_device *dev)
> >  {
> > -	return ITAB_NUM;
> > +	struct net_device_context *ndc = netdev_priv(dev);
> > +
> > +	return ndc->rx_table_sz;
> >  }
> >  
> >  static int netvsc_get_rxfh(struct net_device *dev, u32 *indir, u8 *key,
> > @@ -1766,7 +1768,7 @@ static int netvsc_get_rxfh(struct net_device *dev, u32 *indir, u8 *key,
> >  
> >  	rndis_dev = ndev->extension;
> >  	if (indir) {
> > -		for (i = 0; i < ITAB_NUM; i++)
> > +		for (i = 0; i < ndc->rx_table_sz; i++)
> >  			indir[i] = ndc->rx_table[i];
> >  	}
> >  
> > @@ -1792,11 +1794,11 @@ static int netvsc_set_rxfh(struct net_device *dev, const u32 *indir,
> >  
> >  	rndis_dev = ndev->extension;
> >  	if (indir) {
> > -		for (i = 0; i < ITAB_NUM; i++)
> > +		for (i = 0; i < ndc->rx_table_sz; i++)
> >  			if (indir[i] >= ndev->num_chn)
> >  				return -EINVAL;
> >  
> > -		for (i = 0; i < ITAB_NUM; i++)
> > +		for (i = 0; i < ndc->rx_table_sz; i++)
> >  			ndc->rx_table[i] = indir[i];
> >  	}
> >  
> > diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
> > index eea777ec2541..dc7b9b326690 100644
> > --- a/drivers/net/hyperv/rndis_filter.c
> > +++ b/drivers/net/hyperv/rndis_filter.c
> > @@ -21,6 +21,7 @@
> >  #include <linux/rtnetlink.h>
> >  #include <linux/ucs2_string.h>
> >  #include <linux/string.h>
> > +#include <linux/slab.h>
> >  
> >  #include "hyperv_net.h"
> >  #include "netvsc_trace.h"
> > @@ -927,7 +928,7 @@ static int rndis_set_rss_param_msg(struct rndis_device *rdev,
> >  	struct rndis_set_request *set;
> >  	struct rndis_set_complete *set_complete;
> >  	u32 extlen = sizeof(struct ndis_recv_scale_param) +
> > -		     4 * ITAB_NUM + NETVSC_HASH_KEYLEN;
> > +		     4 * ndc->rx_table_sz + NETVSC_HASH_KEYLEN;
> >  	struct ndis_recv_scale_param *rssp;
> >  	u32 *itab;
> >  	u8 *keyp;
> > @@ -953,7 +954,7 @@ static int rndis_set_rss_param_msg(struct rndis_device *rdev,
> >  	rssp->hashinfo = NDIS_HASH_FUNC_TOEPLITZ | NDIS_HASH_IPV4 |
> >  			 NDIS_HASH_TCP_IPV4 | NDIS_HASH_IPV6 |
> >  			 NDIS_HASH_TCP_IPV6;
> > -	rssp->indirect_tabsize = 4*ITAB_NUM;
> > +	rssp->indirect_tabsize = 4 * ndc->rx_table_sz;
> >  	rssp->indirect_taboffset = sizeof(struct ndis_recv_scale_param);
> >  	rssp->hashkey_size = NETVSC_HASH_KEYLEN;
> >  	rssp->hashkey_offset = rssp->indirect_taboffset +
> > @@ -961,7 +962,7 @@ static int rndis_set_rss_param_msg(struct rndis_device *rdev,
> >  
> >  	/* Set indirection table entries */
> >  	itab = (u32 *)(rssp + 1);
> > -	for (i = 0; i < ITAB_NUM; i++)
> > +	for (i = 0; i < ndc->rx_table_sz; i++)
> >  		itab[i] = ndc->rx_table[i];
> >  
> >  	/* Set hask key values */
> > @@ -1548,6 +1549,17 @@ struct netvsc_device *rndis_filter_device_add(struct hv_device *dev,
> >  	if (ret || rsscap.num_recv_que < 2)
> >  		goto out;
> >  
> > +	if (rsscap.num_indirect_tabent &&
> > +	    rsscap.num_indirect_tabent <= ITAB_NUM_MAX)
> > +		ndc->rx_table_sz = rsscap.num_indirect_tabent;
> > +	else
> > +		ndc->rx_table_sz = ITAB_NUM;
> > +
> > +	ndc->rx_table = kcalloc(ndc->rx_table_sz, sizeof(u16),
> > +				GFP_KERNEL);
> > +	if (!ndc->rx_table)
> > +		goto err_dev_remv;
> > +
> >  	/* This guarantees that num_possible_rss_qs <= num_online_cpus */
> >  	num_possible_rss_qs = min_t(u32, num_online_cpus(),
> >  				    rsscap.num_recv_que);
> > @@ -1558,7 +1570,7 @@ struct netvsc_device *rndis_filter_device_add(struct hv_device *dev,
> >  	net_device->num_chn = min(net_device->max_chn, device_info->num_chn);
> >  
> >  	if (!netif_is_rxfh_configured(net)) {
> > -		for (i = 0; i < ITAB_NUM; i++)
> > +		for (i = 0; i < ndc->rx_table_sz; i++)
> >  			ndc->rx_table[i] = ethtool_rxfh_indir_default(
> >  						i, net_device->num_chn);
> >  	}
> > @@ -1596,11 +1608,18 @@ void rndis_filter_device_remove(struct hv_device *dev,
> >  				struct netvsc_device *net_dev)
> >  {
> >  	struct rndis_device *rndis_dev = net_dev->extension;
> > +	struct net_device *net = hv_get_drvdata(dev);
> > +	struct net_device_context *ndc = netdev_priv(net);
> >  
> >  	/* Halt and release the rndis device */
> >  	rndis_filter_halt_device(net_dev, rndis_dev);
> >  
> >  	netvsc_device_remove(dev);
> 
> Shouldn't the netvsc_device_remove be called post table cleanup ? or better, the cleanup should happen as part of netvsc_device_remove operation ? This looks a bug to me as with remove operation, we already cleaned up the device and the association between context and device is removed.

The netvsc_device_remove() function is responsible for cleaning up/removing the netvsc_device structures upon events like remove/suspend. The net_device and net_device_context structures(where the rx indirection table exists) remain untouched in netvsc_device_remove(). They(net_device, net_device_context) only get cleaned up in netvsc_remove(). So, the netvsc_device_remove() should not affect the cleanup for the rx indirection table, that we did.

> > +
> > +	ndc->rx_table_sz = 0;
> > +	kfree(ndc->rx_table);
> > +	ndc->rx_table = NULL;
> > +
> >  }
> >  
> >  int rndis_filter_open(struct netvsc_device *nvdev)

Re: [PATCH v3] hv_netvsc: Allocate rx indirection table size dynamically

[Christophe JAILLET]

Le 26/05/2023 à 08:02, Shradha Gupta a écrit :
> Allocate the size of rx indirection table dynamically in netvsc
> from the value of size provided by OID_GEN_RECEIVE_SCALE_CAPABILITIES
> query instead of using a constant value of ITAB_NUM.
> 
> Signed-off-by: Shradha Gupta <shradhagupta@linux.microsoft.com>
> Tested-on: Ubuntu22 (azure VM, SKU size: Standard_F72s_v2)
> Testcases:
> 1. ethtool -x eth0 output
> 2. LISA testcase:PERF-NETWORK-TCP-THROUGHPUT-MULTICONNECTION-NTTTCP-Synthetic
> 3. LISA testcase:PERF-NETWORK-TCP-THROUGHPUT-MULTICONNECTION-NTTTCP-SRIOV
> 
> ---

[...]

> @@ -1596,11 +1608,18 @@ void rndis_filter_device_remove(struct hv_device *dev,
>   				struct netvsc_device *net_dev)
>   {
>   	struct rndis_device *rndis_dev = net_dev->extension;
> +	struct net_device *net = hv_get_drvdata(dev);
> +	struct net_device_context *ndc = netdev_priv(net);
>   
>   	/* Halt and release the rndis device */
>   	rndis_filter_halt_device(net_dev, rndis_dev);
>   
>   	netvsc_device_remove(dev);
> +
> +	ndc->rx_table_sz = 0;
> +	kfree(ndc->rx_table);
> +	ndc->rx_table = NULL;
> +

Nit: useless empty NL

>   }
>   
>   int rndis_filter_open(struct netvsc_device *nvdev)

Re: [PATCH v3] hv_netvsc: Allocate rx indirection table size dynamically

[Shradha Gupta]

Thanks for the comment Christophe.
On Mon, May 29, 2023 at 02:49:15PM +0200, Christophe JAILLET wrote:
> Le 26/05/2023 ?? 08:02, Shradha Gupta a ??crit??:
> >Allocate the size of rx indirection table dynamically in netvsc
> >from the value of size provided by OID_GEN_RECEIVE_SCALE_CAPABILITIES
> >query instead of using a constant value of ITAB_NUM.
> >
> >Signed-off-by: Shradha Gupta <shradhagupta@linux.microsoft.com>
> >Tested-on: Ubuntu22 (azure VM, SKU size: Standard_F72s_v2)
> >Testcases:
> >1. ethtool -x eth0 output
> >2. LISA testcase:PERF-NETWORK-TCP-THROUGHPUT-MULTICONNECTION-NTTTCP-Synthetic
> >3. LISA testcase:PERF-NETWORK-TCP-THROUGHPUT-MULTICONNECTION-NTTTCP-SRIOV
> >
> >---
> 
> [...]
> 
> >@@ -1596,11 +1608,18 @@ void rndis_filter_device_remove(struct hv_device *dev,
> >  				struct netvsc_device *net_dev)
> >  {
> >  	struct rndis_device *rndis_dev = net_dev->extension;
> >+	struct net_device *net = hv_get_drvdata(dev);
> >+	struct net_device_context *ndc = netdev_priv(net);
> >  	/* Halt and release the rndis device */
> >  	rndis_filter_halt_device(net_dev, rndis_dev);
> >  	netvsc_device_remove(dev);
> >+
> >+	ndc->rx_table_sz = 0;
> >+	kfree(ndc->rx_table);
> >+	ndc->rx_table = NULL;
> >+
> 
> Nit: useless empty NL
This is to prevent any potential double free, or accessing freed memory, etc.
As requested by Haiyang in v2 patch
> 
> >  }
> >  int rndis_filter_open(struct netvsc_device *nvdev)

Re: [PATCH v3] hv_netvsc: Allocate rx indirection table size dynamically

[Christophe JAILLET]

Le 29/05/2023 à 15:30, Shradha Gupta a écrit :
> Thanks for the comment Christophe.
> On Mon, May 29, 2023 at 02:49:15PM +0200, Christophe JAILLET wrote:
>> Le 26/05/2023 ?? 08:02, Shradha Gupta a ??crit??:
>>> Allocate the size of rx indirection table dynamically in netvsc
>> >from the value of size provided by OID_GEN_RECEIVE_SCALE_CAPABILITIES
>>> query instead of using a constant value of ITAB_NUM.
>>>
>>> Signed-off-by: Shradha Gupta <shradhagupta@linux.microsoft.com>
>>> Tested-on: Ubuntu22 (azure VM, SKU size: Standard_F72s_v2)
>>> Testcases:
>>> 1. ethtool -x eth0 output
>>> 2. LISA testcase:PERF-NETWORK-TCP-THROUGHPUT-MULTICONNECTION-NTTTCP-Synthetic
>>> 3. LISA testcase:PERF-NETWORK-TCP-THROUGHPUT-MULTICONNECTION-NTTTCP-SRIOV
>>>
>>> ---
>>
>> [...]
>>
>>> @@ -1596,11 +1608,18 @@ void rndis_filter_device_remove(struct hv_device *dev,
>>>   				struct netvsc_device *net_dev)
>>>   {
>>>   	struct rndis_device *rndis_dev = net_dev->extension;
>>> +	struct net_device *net = hv_get_drvdata(dev);
>>> +	struct net_device_context *ndc = netdev_priv(net);
>>>   	/* Halt and release the rndis device */
>>>   	rndis_filter_halt_device(net_dev, rndis_dev);
>>>   	netvsc_device_remove(dev);
>>> +
>>> +	ndc->rx_table_sz = 0;
>>> +	kfree(ndc->rx_table);
>>> +	ndc->rx_table = NULL;
>>> +
>>
>> Nit: useless empty NL
> This is to prevent any potential double free, or accessing freed memory, etc.
> As requested by Haiyang in v2 patch

Setting ndc->rx_table to NULL is fine, but there is a useless *newline* 
(NL) just after.
If you have to send a v4, you can save a line of code.

CJ

>>
>>>   }
>>>   int rndis_filter_open(struct netvsc_device *nvdev)
> 

RE: [PATCH v3] hv_netvsc: Allocate rx indirection table size dynamically

[Haiyang Zhang]

> -----Original Message-----
> From: Shradha Gupta <shradhagupta@linux.microsoft.com>
> Sent: Friday, May 26, 2023 2:02 AM
> To: linux-kernel@vger.kernel.org; linux-hyperv@vger.kernel.org;
> netdev@vger.kernel.org
> Cc: Shradha Gupta <shradhagupta@linux.microsoft.com>; Eric Dumazet
> <edumazet@google.com>; Jakub Kicinski <kuba@kernel.org>; Paolo Abeni
> <pabeni@redhat.com>; KY Srinivasan <kys@microsoft.com>; Haiyang Zhang
> <haiyangz@microsoft.com>; Wei Liu <wei.liu@kernel.org>; Dexuan Cui
> <decui@microsoft.com>; Long Li <longli@microsoft.com>; Michael Kelley
> (LINUX) <mikelley@microsoft.com>; David S. Miller <davem@davemloft.net>;
> Steen Hegelund <steen.hegelund@microchip.com>; Simon Horman
> <simon.horman@corigine.com>
> Subject: [PATCH v3] hv_netvsc: Allocate rx indirection table size dynamically
> 
> Allocate the size of rx indirection table dynamically in netvsc
> from the value of size provided by OID_GEN_RECEIVE_SCALE_CAPABILITIES
> query instead of using a constant value of ITAB_NUM.
> 
> Signed-off-by: Shradha Gupta <shradhagupta@linux.microsoft.com>
> Tested-on: Ubuntu22 (azure VM, SKU size: Standard_F72s_v2)
> Testcases:
> 1. ethtool -x eth0 output
> 2. LISA testcase:PERF-NETWORK-TCP-THROUGHPUT-MULTICONNECTION-
> NTTTCP-Synthetic
> 3. LISA testcase:PERF-NETWORK-TCP-THROUGHPUT-MULTICONNECTION-
> NTTTCP-SRIOV

Thank you!

Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>

Re: [PATCH v3] hv_netvsc: Allocate rx indirection table size dynamically

[Praveen Kumar]

On 5/29/2023 4:47 PM, Shradha Gupta wrote:
> On Mon, May 29, 2023 at 03:09:49PM +0530, Praveen Kumar wrote:
>> On 5/26/2023 11:32 AM, Shradha Gupta wrote:
>>> Allocate the size of rx indirection table dynamically in netvsc
>>> from the value of size provided by OID_GEN_RECEIVE_SCALE_CAPABILITIES
>>> query instead of using a constant value of ITAB_NUM.
>>>
>>> Signed-off-by: Shradha Gupta <shradhagupta@linux.microsoft.com>
>>> Tested-on: Ubuntu22 (azure VM, SKU size: Standard_F72s_v2)
>>> Testcases:
>>> 1. ethtool -x eth0 output
>>> 2. LISA testcase:PERF-NETWORK-TCP-THROUGHPUT-MULTICONNECTION-NTTTCP-Synthetic
>>> 3. LISA testcase:PERF-NETWORK-TCP-THROUGHPUT-MULTICONNECTION-NTTTCP-SRIOV
>>>
>>> ---
>>> Changes in v3:
>>>  * Changed the data type of rx_table_sz to u32
>>>  * Moved the rx indirection table free to rndis_filter_device_remove()
>>>  * Device add will fail with error if not enough memory is available
>>>  * Changed kzmalloc to kcalloc as suggested in checkpatch script
>>>  * Removed redundant log if memory allocation failed.
>>> ---
>>>  drivers/net/hyperv/hyperv_net.h   |  5 ++++-
>>>  drivers/net/hyperv/netvsc_drv.c   | 10 ++++++----
>>>  drivers/net/hyperv/rndis_filter.c | 27 +++++++++++++++++++++++----
>>>  3 files changed, 33 insertions(+), 9 deletions(-)
>>>
>>> diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
>>> index dd5919ec408b..c40868f287a9 100644
>>> --- a/drivers/net/hyperv/hyperv_net.h
>>> +++ b/drivers/net/hyperv/hyperv_net.h
>>> @@ -74,6 +74,7 @@ struct ndis_recv_scale_cap { /* NDIS_RECEIVE_SCALE_CAPABILITIES */
>>>  #define NDIS_RSS_HASH_SECRET_KEY_MAX_SIZE_REVISION_2   40
>>>  
>>>  #define ITAB_NUM 128
>>> +#define ITAB_NUM_MAX 256
>>>  
>>>  struct ndis_recv_scale_param { /* NDIS_RECEIVE_SCALE_PARAMETERS */
>>>  	struct ndis_obj_header hdr;
>>> @@ -1034,7 +1035,9 @@ struct net_device_context {
>>>  
>>>  	u32 tx_table[VRSS_SEND_TAB_SIZE];
>>>  
>>> -	u16 rx_table[ITAB_NUM];
>>> +	u16 *rx_table;
>>> +
>>> +	u32 rx_table_sz;
>>>  
>>>  	/* Ethtool settings */
>>>  	u8 duplex;
>>> diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
>>> index 0103ff914024..3ba3c8fb28a5 100644
>>> --- a/drivers/net/hyperv/netvsc_drv.c
>>> +++ b/drivers/net/hyperv/netvsc_drv.c
>>> @@ -1747,7 +1747,9 @@ static u32 netvsc_get_rxfh_key_size(struct net_device *dev)
>>>  
>>>  static u32 netvsc_rss_indir_size(struct net_device *dev)
>>>  {
>>> -	return ITAB_NUM;
>>> +	struct net_device_context *ndc = netdev_priv(dev);
>>> +
>>> +	return ndc->rx_table_sz;
>>>  }
>>>  
>>>  static int netvsc_get_rxfh(struct net_device *dev, u32 *indir, u8 *key,
>>> @@ -1766,7 +1768,7 @@ static int netvsc_get_rxfh(struct net_device *dev, u32 *indir, u8 *key,
>>>  
>>>  	rndis_dev = ndev->extension;
>>>  	if (indir) {
>>> -		for (i = 0; i < ITAB_NUM; i++)
>>> +		for (i = 0; i < ndc->rx_table_sz; i++)
>>>  			indir[i] = ndc->rx_table[i];
>>>  	}
>>>  
>>> @@ -1792,11 +1794,11 @@ static int netvsc_set_rxfh(struct net_device *dev, const u32 *indir,
>>>  
>>>  	rndis_dev = ndev->extension;
>>>  	if (indir) {
>>> -		for (i = 0; i < ITAB_NUM; i++)
>>> +		for (i = 0; i < ndc->rx_table_sz; i++)
>>>  			if (indir[i] >= ndev->num_chn)
>>>  				return -EINVAL;
>>>  
>>> -		for (i = 0; i < ITAB_NUM; i++)
>>> +		for (i = 0; i < ndc->rx_table_sz; i++)
>>>  			ndc->rx_table[i] = indir[i];
>>>  	}
>>>  
>>> diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
>>> index eea777ec2541..dc7b9b326690 100644
>>> --- a/drivers/net/hyperv/rndis_filter.c
>>> +++ b/drivers/net/hyperv/rndis_filter.c
>>> @@ -21,6 +21,7 @@
>>>  #include <linux/rtnetlink.h>
>>>  #include <linux/ucs2_string.h>
>>>  #include <linux/string.h>
>>> +#include <linux/slab.h>
>>>  
>>>  #include "hyperv_net.h"
>>>  #include "netvsc_trace.h"
>>> @@ -927,7 +928,7 @@ static int rndis_set_rss_param_msg(struct rndis_device *rdev,
>>>  	struct rndis_set_request *set;
>>>  	struct rndis_set_complete *set_complete;
>>>  	u32 extlen = sizeof(struct ndis_recv_scale_param) +
>>> -		     4 * ITAB_NUM + NETVSC_HASH_KEYLEN;
>>> +		     4 * ndc->rx_table_sz + NETVSC_HASH_KEYLEN;
>>>  	struct ndis_recv_scale_param *rssp;
>>>  	u32 *itab;
>>>  	u8 *keyp;
>>> @@ -953,7 +954,7 @@ static int rndis_set_rss_param_msg(struct rndis_device *rdev,
>>>  	rssp->hashinfo = NDIS_HASH_FUNC_TOEPLITZ | NDIS_HASH_IPV4 |
>>>  			 NDIS_HASH_TCP_IPV4 | NDIS_HASH_IPV6 |
>>>  			 NDIS_HASH_TCP_IPV6;
>>> -	rssp->indirect_tabsize = 4*ITAB_NUM;
>>> +	rssp->indirect_tabsize = 4 * ndc->rx_table_sz;
>>>  	rssp->indirect_taboffset = sizeof(struct ndis_recv_scale_param);
>>>  	rssp->hashkey_size = NETVSC_HASH_KEYLEN;
>>>  	rssp->hashkey_offset = rssp->indirect_taboffset +
>>> @@ -961,7 +962,7 @@ static int rndis_set_rss_param_msg(struct rndis_device *rdev,
>>>  
>>>  	/* Set indirection table entries */
>>>  	itab = (u32 *)(rssp + 1);
>>> -	for (i = 0; i < ITAB_NUM; i++)
>>> +	for (i = 0; i < ndc->rx_table_sz; i++)
>>>  		itab[i] = ndc->rx_table[i];
>>>  
>>>  	/* Set hask key values */
>>> @@ -1548,6 +1549,17 @@ struct netvsc_device *rndis_filter_device_add(struct hv_device *dev,
>>>  	if (ret || rsscap.num_recv_que < 2)
>>>  		goto out;
>>>  
>>> +	if (rsscap.num_indirect_tabent &&
>>> +	    rsscap.num_indirect_tabent <= ITAB_NUM_MAX)
>>> +		ndc->rx_table_sz = rsscap.num_indirect_tabent;
>>> +	else
>>> +		ndc->rx_table_sz = ITAB_NUM;
>>> +
>>> +	ndc->rx_table = kcalloc(ndc->rx_table_sz, sizeof(u16),
>>> +				GFP_KERNEL);
>>> +	if (!ndc->rx_table)
>>> +		goto err_dev_remv;
>>> +
>>>  	/* This guarantees that num_possible_rss_qs <= num_online_cpus */
>>>  	num_possible_rss_qs = min_t(u32, num_online_cpus(),
>>>  				    rsscap.num_recv_que);
>>> @@ -1558,7 +1570,7 @@ struct netvsc_device *rndis_filter_device_add(struct hv_device *dev,
>>>  	net_device->num_chn = min(net_device->max_chn, device_info->num_chn);
>>>  
>>>  	if (!netif_is_rxfh_configured(net)) {
>>> -		for (i = 0; i < ITAB_NUM; i++)
>>> +		for (i = 0; i < ndc->rx_table_sz; i++)
>>>  			ndc->rx_table[i] = ethtool_rxfh_indir_default(
>>>  						i, net_device->num_chn);
>>>  	}
>>> @@ -1596,11 +1608,18 @@ void rndis_filter_device_remove(struct hv_device *dev,
>>>  				struct netvsc_device *net_dev)
>>>  {
>>>  	struct rndis_device *rndis_dev = net_dev->extension;
>>> +	struct net_device *net = hv_get_drvdata(dev);
>>> +	struct net_device_context *ndc = netdev_priv(net);
>>>  
>>>  	/* Halt and release the rndis device */
>>>  	rndis_filter_halt_device(net_dev, rndis_dev);
>>>  
>>>  	netvsc_device_remove(dev);
>>
>> Shouldn't the netvsc_device_remove be called post table cleanup ? or better, the cleanup should happen as part of netvsc_device_remove operation ? This looks a bug to me as with remove operation, we already cleaned up the device and the association between context and device is removed.
> 
> The netvsc_device_remove() function is responsible for cleaning up/removing the netvsc_device structures upon events like remove/suspend. The net_device and net_device_context structures(where the rx indirection table exists) remain untouched in netvsc_device_remove(). They(net_device, net_device_context) only get cleaned up in netvsc_remove(). So, the netvsc_device_remove() should not affect the cleanup for the rx indirection table, that we did.
> 

Thanks.

Reviewed-by: Praveen Kumar <kumarpraveen@linux.microsoft.com>