diff mbox series

[RFC,v2,net-next,2/7] net: ethtool: attach an IDR of custom RSS contexts to a netdevice

Message ID 16030cc69a6726cda461290a3d6bed9c48db7562.1681236653.git.ecree.xilinx@gmail.com (mailing list archive)
State RFC
Delegated to: Netdev Maintainers
Headers show
Series ethtool: track custom RSS contexts in the core | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next, async
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 1891 this patch: 1891
netdev/cc_maintainers warning 1 maintainers not CCed: vladimir.oltean@nxp.com
netdev/build_clang success Errors and warnings before: 555 this patch: 555
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 2000 this patch: 2000
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 97 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

edward.cree@amd.com April 11, 2023, 6:26 p.m. UTC 
From: Edward Cree <ecree.xilinx@gmail.com>

Each context stores the RXFH settings (indir, key, and hfunc) as well
 as optionally some driver private data.
Delete any still-existing contexts at netdev unregister time.

Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
---
Changes in v2: fix data area to ensure proper alignment (kuba)
---
 include/linux/ethtool.h | 41 +++++++++++++++++++++++++++++++++++++++++
 net/core/dev.c          | 23 +++++++++++++++++++++++
 2 files changed, 64 insertions(+)

Comments

Andrew Lunn April 11, 2023, 8:36 p.m. UTC | #1 
>  /**
>   * struct ethtool_netdev_state - per-netdevice state for ethtool features
> + * @rss_ctx_max_id:	maximum (exclusive) supported RSS context ID
> + * @rss_ctx:		IDR storing custom RSS context state
>   * @wol_enabled:	Wake-on-LAN is enabled
>   */
>  struct ethtool_netdev_state {
> +	u32			rss_ctx_max_id;
> +	struct idr		rss_ctx;
>  	unsigned		wol_enabled:1;
>  };

A nitpick. On 64 bit systems, you have a hole between rss_ctx_max_id
and rss_ctx. If you swap those around, and change wol_enabled to also
be a u32 bitfield, the compiler can probably do without the hole.

   Andrew
Edward Cree April 12, 2023, 3:52 p.m. UTC | #2 
On 11/04/2023 21:36, Andrew Lunn wrote:
>>  /**
>>   * struct ethtool_netdev_state - per-netdevice state for ethtool features
>> + * @rss_ctx_max_id:	maximum (exclusive) supported RSS context ID
>> + * @rss_ctx:		IDR storing custom RSS context state
>>   * @wol_enabled:	Wake-on-LAN is enabled
>>   */
>>  struct ethtool_netdev_state {
>> +	u32			rss_ctx_max_id;
>> +	struct idr		rss_ctx;
>>  	unsigned		wol_enabled:1;
>>  };
> 
> A nitpick. On 64 bit systems, you have a hole between rss_ctx_max_id
> and rss_ctx. If you swap those around, and change wol_enabled to also
> be a u32 bitfield, the compiler can probably do without the hole.

Sure, makes sense.
Jakub Kicinski April 13, 2023, 1:39 a.m. UTC | #3 
On Tue, 11 Apr 2023 19:26:10 +0100 edward.cree@amd.com wrote:
> +static void netdev_rss_contexts_free(struct net_device *dev)
> +{
> +	struct ethtool_rxfh_context *ctx;
> +	u32 context;
> +
> +	if (!dev->ethtool_ops->set_rxfh_context)
> +		return;
> +	idr_for_each_entry(&dev->ethtool->rss_ctx, ctx, context) {
> +		u32 *indir = ethtool_rxfh_context_indir(ctx);
> +		u8 *key = ethtool_rxfh_context_key(ctx);
> +
> +		idr_remove(&dev->ethtool->rss_ctx, context);
> +		dev->ethtool_ops->set_rxfh_context(dev, indir, key, ctx->hfunc,
> +						   &context, true);
> +		kfree(ctx);
> +	}
> +}

nit: maybe move the ethtool related code out to a new
net/ethtool/netdev.c ? We can probably put forward declarations 
in net/core/dev.h or a new header among sources?
diff mbox series

Patch

diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index c73b28df301c..7963b06da484 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -157,6 +157,43 @@  static inline u32 ethtool_rxfh_indir_default(u32 index, u32 n_rx_rings)
 	return index % n_rx_rings;
 }
 
+/**
+ * struct ethtool_rxfh_context - a custom RSS context configuration
+ * @indir_size: Number of u32 entries in indirection table
+ * @key_size: Size of hash key, in bytes
+ * @hfunc: RSS hash function identifier.  One of the %ETH_RSS_HASH_*
+ * @priv_size: Size of driver private data, in bytes
+ * @indir_no_change: indir was not specified at create time
+ * @key_no_change: hkey was not specified at create time
+ */
+struct ethtool_rxfh_context {
+	u32 indir_size;
+	u32 key_size;
+	u8 hfunc;
+	u16 priv_size;
+	u8 indir_no_change:1;
+	u8 key_no_change:1;
+	/* private: driver private data, indirection table, and hash key are
+	 * stored sequentially in @data area.  Use below helpers to access.
+	 */
+	u8 data[] __aligned(sizeof(void *));
+};
+
+static inline void *ethtool_rxfh_context_priv(struct ethtool_rxfh_context *ctx)
+{
+	return ctx->data;
+}
+
+static inline u32 *ethtool_rxfh_context_indir(struct ethtool_rxfh_context *ctx)
+{
+	return (u32 *)(ctx->data + ALIGN(ctx->priv_size, sizeof(u32)));
+}
+
+static inline u8 *ethtool_rxfh_context_key(struct ethtool_rxfh_context *ctx)
+{
+	return (u8 *)(ethtool_rxfh_context_indir(ctx) + ctx->indir_size);
+}
+
 /* declare a link mode bitmap */
 #define __ETHTOOL_DECLARE_LINK_MODE_MASK(name)		\
 	DECLARE_BITMAP(name, __ETHTOOL_LINK_MODE_MASK_NBITS)
@@ -936,9 +973,13 @@  int ethtool_virtdev_set_link_ksettings(struct net_device *dev,
 
 /**
  * struct ethtool_netdev_state - per-netdevice state for ethtool features
+ * @rss_ctx_max_id:	maximum (exclusive) supported RSS context ID
+ * @rss_ctx:		IDR storing custom RSS context state
  * @wol_enabled:	Wake-on-LAN is enabled
  */
 struct ethtool_netdev_state {
+	u32			rss_ctx_max_id;
+	struct idr		rss_ctx;
 	unsigned		wol_enabled:1;
 };
 
diff --git a/net/core/dev.c b/net/core/dev.c
index 93960861a11f..c9ed9f6ea695 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -9983,6 +9983,9 @@  int register_netdevice(struct net_device *dev)
 	if (ret)
 		return ret;
 
+	/* rss ctx ID 0 is reserved for the default context, start from 1 */
+	idr_init_base(&dev->ethtool->rss_ctx, 1);
+
 	spin_lock_init(&dev->addr_list_lock);
 	netdev_set_addr_lockdep_class(dev);
 
@@ -10781,6 +10784,24 @@  void synchronize_net(void)
 }
 EXPORT_SYMBOL(synchronize_net);
 
+static void netdev_rss_contexts_free(struct net_device *dev)
+{
+	struct ethtool_rxfh_context *ctx;
+	u32 context;
+
+	if (!dev->ethtool_ops->set_rxfh_context)
+		return;
+	idr_for_each_entry(&dev->ethtool->rss_ctx, ctx, context) {
+		u32 *indir = ethtool_rxfh_context_indir(ctx);
+		u8 *key = ethtool_rxfh_context_key(ctx);
+
+		idr_remove(&dev->ethtool->rss_ctx, context);
+		dev->ethtool_ops->set_rxfh_context(dev, indir, key, ctx->hfunc,
+						   &context, true);
+		kfree(ctx);
+	}
+}
+
 /**
  *	unregister_netdevice_queue - remove device from the kernel
  *	@dev: device
@@ -10885,6 +10906,8 @@  void unregister_netdevice_many_notify(struct list_head *head,
 		netdev_name_node_alt_flush(dev);
 		netdev_name_node_free(dev->name_node);
 
+		netdev_rss_contexts_free(dev);
+
 		call_netdevice_notifiers(NETDEV_PRE_UNINIT, dev);
 
 		if (dev->netdev_ops->ndo_uninit)