[RFC] ethtool: Support ETHTOOL_GSTATS2 command.
diff mbox

Message ID 1520452289-14172-1-git-send-email-greearb@candelatech.com
State New
Headers show

Commit Message

Ben Greear March 7, 2018, 7:51 p.m. UTC
From: Ben Greear <greearb@candelatech.com>

This is similar to ETHTOOL_GSTATS, but it allows you to specify
a 'level'.  This level can be used by the driver to decrease the
amount of stats refreshed.  In particular, this helps with ath10k
since getting the firmware stats can be slow.

Signed-off-by: Ben Greear <greearb@candelatech.com>
---

NOTE:  I know to make it upstream I would need to split the patch and
remove the #define for 'backporting' that I added.  But, is the
feature in general wanted?  If so, I'll do the patch split and
other tweaks that might be suggested.

 drivers/net/wireless/ath/ath10k/debug.c | 18 ++++++++++--
 drivers/net/wireless/ath/ath10k/debug.h |  3 ++
 drivers/net/wireless/ath/ath10k/mac.c   |  3 ++
 include/linux/ethtool.h                 | 10 +++++++
 include/net/mac80211.h                  |  6 ++++
 include/uapi/linux/ethtool.h            |  4 +++
 net/core/ethtool.c                      | 52 +++++++++++++++++++++++++++++++++
 net/mac80211/driver-ops.h               |  9 ++++--
 net/mac80211/ethtool.c                  | 16 +++++++---
 9 files changed, 112 insertions(+), 9 deletions(-)

Comments

Michal Kubecek March 20, 2018, 10:37 a.m. UTC | #1
On Wed, Mar 07, 2018 at 11:51:29AM -0800, greearb@candelatech.com wrote:
> From: Ben Greear <greearb@candelatech.com>
> 
> This is similar to ETHTOOL_GSTATS, but it allows you to specify
> a 'level'.  This level can be used by the driver to decrease the
> amount of stats refreshed.  In particular, this helps with ath10k
> since getting the firmware stats can be slow.
> 
> Signed-off-by: Ben Greear <greearb@candelatech.com>
> ---
> 
> NOTE:  I know to make it upstream I would need to split the patch and
> remove the #define for 'backporting' that I added.  But, is the
> feature in general wanted?  If so, I'll do the patch split and
> other tweaks that might be suggested.

I'm not familiar enough with the technical background of stats
collecting to comment on usefulness and desirability of this feature.
Adding a new command just to add a numeric parameter certainly doesn't
feel right but it's how the ioctl interface works. I take it as
a reminder to find some time to get back to the netlink interface.

> diff --git a/net/core/ethtool.c b/net/core/ethtool.c
> index 674b6c9..d3b709f 100644
> --- a/net/core/ethtool.c
> +++ b/net/core/ethtool.c
> @@ -1947,6 +1947,54 @@ static int ethtool_get_stats(struct net_device *dev, void __user *useraddr)
>  	return ret;
>  }
>  
> +static int ethtool_get_stats2(struct net_device *dev, void __user *useraddr)
> +{
> +	struct ethtool_stats stats;
> +	const struct ethtool_ops *ops = dev->ethtool_ops;
> +	u64 *data;
> +	int ret, n_stats;
> +	u32 stats_level = 0;
> +
> +	if (!ops->get_ethtool_stats2 || !ops->get_sset_count)
> +		return -EOPNOTSUPP;
> +
> +	n_stats = ops->get_sset_count(dev, ETH_SS_STATS);
> +	if (n_stats < 0)
> +		return n_stats;
> +	if (n_stats > S32_MAX / sizeof(u64))
> +		return -ENOMEM;
> +	WARN_ON_ONCE(!n_stats);
> +	if (copy_from_user(&stats, useraddr, sizeof(stats)))
> +		return -EFAULT;
> +
> +	/* User can specify the level of stats to query.  How the
> +	 * level value is used is up to the driver, but in general,
> +	 * 0 means 'all', 1 means least, and higher means more.
> +	 * The idea is that some stats may be expensive to query, so user
> +	 * space could just ask for the cheap ones...
> +	 */
> +	stats_level = stats.n_stats;
> +
> +	stats.n_stats = n_stats;
> +	data = vzalloc(n_stats * sizeof(u64));
> +	if (n_stats && !data)
> +		return -ENOMEM;
> +
> +	ops->get_ethtool_stats2(dev, &stats, data, stats_level);
> +
> +	ret = -EFAULT;
> +	if (copy_to_user(useraddr, &stats, sizeof(stats)))
> +		goto out;
> +	useraddr += sizeof(stats);
> +	if (n_stats && copy_to_user(useraddr, data, n_stats * sizeof(u64)))
> +		goto out;
> +	ret = 0;
> +
> + out:
> +	vfree(data);
> +	return ret;
> +}
> +
>  static int ethtool_get_phy_stats(struct net_device *dev, void __user *useraddr)
>  {
>  	struct ethtool_stats stats;

IMHO it would be more practical to set "0 means same as GSTATS" as a
rule and make ethtool_get_stats() a wrapper for ethtool_get_stats2() to
avoid code duplication (or perhaps a use fall-through in the switch). It
would also allow drivers to provide only one of the callbacks.

Michal Kubecek
Ben Greear March 20, 2018, 3:39 p.m. UTC | #2
On 03/20/2018 03:37 AM, Michal Kubecek wrote:
> On Wed, Mar 07, 2018 at 11:51:29AM -0800, greearb@candelatech.com wrote:
>> From: Ben Greear <greearb@candelatech.com>
>>
>> This is similar to ETHTOOL_GSTATS, but it allows you to specify
>> a 'level'.  This level can be used by the driver to decrease the
>> amount of stats refreshed.  In particular, this helps with ath10k
>> since getting the firmware stats can be slow.
>>
>> Signed-off-by: Ben Greear <greearb@candelatech.com>
>> ---
>>
>> NOTE:  I know to make it upstream I would need to split the patch and
>> remove the #define for 'backporting' that I added.  But, is the
>> feature in general wanted?  If so, I'll do the patch split and
>> other tweaks that might be suggested.
>
> I'm not familiar enough with the technical background of stats
> collecting to comment on usefulness and desirability of this feature.
> Adding a new command just to add a numeric parameter certainly doesn't
> feel right but it's how the ioctl interface works. I take it as
> a reminder to find some time to get back to the netlink interface.
>
>> diff --git a/net/core/ethtool.c b/net/core/ethtool.c
>> index 674b6c9..d3b709f 100644
>> --- a/net/core/ethtool.c
>> +++ b/net/core/ethtool.c
>> @@ -1947,6 +1947,54 @@ static int ethtool_get_stats(struct net_device *dev, void __user *useraddr)
>>  	return ret;
>>  }
>>
>> +static int ethtool_get_stats2(struct net_device *dev, void __user *useraddr)
>> +{
>> +	struct ethtool_stats stats;
>> +	const struct ethtool_ops *ops = dev->ethtool_ops;
>> +	u64 *data;
>> +	int ret, n_stats;
>> +	u32 stats_level = 0;
>> +
>> +	if (!ops->get_ethtool_stats2 || !ops->get_sset_count)
>> +		return -EOPNOTSUPP;
>> +
>> +	n_stats = ops->get_sset_count(dev, ETH_SS_STATS);
>> +	if (n_stats < 0)
>> +		return n_stats;
>> +	if (n_stats > S32_MAX / sizeof(u64))
>> +		return -ENOMEM;
>> +	WARN_ON_ONCE(!n_stats);
>> +	if (copy_from_user(&stats, useraddr, sizeof(stats)))
>> +		return -EFAULT;
>> +
>> +	/* User can specify the level of stats to query.  How the
>> +	 * level value is used is up to the driver, but in general,
>> +	 * 0 means 'all', 1 means least, and higher means more.
>> +	 * The idea is that some stats may be expensive to query, so user
>> +	 * space could just ask for the cheap ones...
>> +	 */
>> +	stats_level = stats.n_stats;
>> +
>> +	stats.n_stats = n_stats;
>> +	data = vzalloc(n_stats * sizeof(u64));
>> +	if (n_stats && !data)
>> +		return -ENOMEM;
>> +
>> +	ops->get_ethtool_stats2(dev, &stats, data, stats_level);
>> +
>> +	ret = -EFAULT;
>> +	if (copy_to_user(useraddr, &stats, sizeof(stats)))
>> +		goto out;
>> +	useraddr += sizeof(stats);
>> +	if (n_stats && copy_to_user(useraddr, data, n_stats * sizeof(u64)))
>> +		goto out;
>> +	ret = 0;
>> +
>> + out:
>> +	vfree(data);
>> +	return ret;
>> +}
>> +
>>  static int ethtool_get_phy_stats(struct net_device *dev, void __user *useraddr)
>>  {
>>  	struct ethtool_stats stats;
>
> IMHO it would be more practical to set "0 means same as GSTATS" as a
> rule and make ethtool_get_stats() a wrapper for ethtool_get_stats2() to
> avoid code duplication (or perhaps a use fall-through in the switch). It
> would also allow drivers to provide only one of the callbacks.

Yes, but that would require changing all drivers at once, and would make backporting
and out-of-tree drivers harder to manage.  I had low hopes that this feature would
make it upstream, so I didn't want to propose any large changes up front.

Thanks,
Ben
Steve deRosier March 20, 2018, 4:11 p.m. UTC | #3
On Tue, Mar 20, 2018 at 8:39 AM, Ben Greear <greearb@candelatech.com> wrote:
> On 03/20/2018 03:37 AM, Michal Kubecek wrote:
>>
>> On Wed, Mar 07, 2018 at 11:51:29AM -0800, greearb@candelatech.com wrote:
>>>
>>> From: Ben Greear <greearb@candelatech.com>
>>>
>>> This is similar to ETHTOOL_GSTATS, but it allows you to specify
>>> a 'level'.  This level can be used by the driver to decrease the
>>> amount of stats refreshed.  In particular, this helps with ath10k
>>> since getting the firmware stats can be slow.
>>>
>>> Signed-off-by: Ben Greear <greearb@candelatech.com>
>>> ---
>>>
>>> NOTE:  I know to make it upstream I would need to split the patch and
>>> remove the #define for 'backporting' that I added.  But, is the
>>> feature in general wanted?  If so, I'll do the patch split and
>>> other tweaks that might be suggested.
>>
>>
>
> Yes, but that would require changing all drivers at once, and would make
> backporting
> and out-of-tree drivers harder to manage.  I had low hopes that this feature
> would
> make it upstream, so I didn't want to propose any large changes up front.
>

Hi Ben,

I find the feature OK, but I'm not thrilled with the arbitrary scale
of "level". Maybe there could be some named values, either on a
spectrum as level already is, similar to the kernel log DEBUG, WARN,
INFO....  type levels. Or named bit flags like the way the ath drivers
do their debug flags for granular results.  Thoughts?

- Steve
Ben Greear March 20, 2018, 4:24 p.m. UTC | #4
On 03/20/2018 09:11 AM, Steve deRosier wrote:
> On Tue, Mar 20, 2018 at 8:39 AM, Ben Greear <greearb@candelatech.com> wrote:
>> On 03/20/2018 03:37 AM, Michal Kubecek wrote:
>>>
>>> On Wed, Mar 07, 2018 at 11:51:29AM -0800, greearb@candelatech.com wrote:
>>>>
>>>> From: Ben Greear <greearb@candelatech.com>
>>>>
>>>> This is similar to ETHTOOL_GSTATS, but it allows you to specify
>>>> a 'level'.  This level can be used by the driver to decrease the
>>>> amount of stats refreshed.  In particular, this helps with ath10k
>>>> since getting the firmware stats can be slow.
>>>>
>>>> Signed-off-by: Ben Greear <greearb@candelatech.com>
>>>> ---
>>>>
>>>> NOTE:  I know to make it upstream I would need to split the patch and
>>>> remove the #define for 'backporting' that I added.  But, is the
>>>> feature in general wanted?  If so, I'll do the patch split and
>>>> other tweaks that might be suggested.
>>>
>>>
>>
>> Yes, but that would require changing all drivers at once, and would make
>> backporting
>> and out-of-tree drivers harder to manage.  I had low hopes that this feature
>> would
>> make it upstream, so I didn't want to propose any large changes up front.
>>
>
> Hi Ben,
>
> I find the feature OK, but I'm not thrilled with the arbitrary scale
> of "level". Maybe there could be some named values, either on a
> spectrum as level already is, similar to the kernel log DEBUG, WARN,
> INFO....  type levels. Or named bit flags like the way the ath drivers
> do their debug flags for granular results.  Thoughts?

Yes, that would be easier to code too.  If there are any other drivers
out there that might take advantage of this, maybe they could chime in with
what levels and/or bit-fields they would like to see.

For instance a bit that says 'refresh-stats-from-firmware' would be great for ath10k,
but maybe useless for everyone else....

Thanks,
Ben

>
> - Steve
>
Michal Kubecek March 20, 2018, 6:24 p.m. UTC | #5
On Tue, Mar 20, 2018 at 08:39:33AM -0700, Ben Greear wrote:
> On 03/20/2018 03:37 AM, Michal Kubecek wrote:
> > 
> > IMHO it would be more practical to set "0 means same as GSTATS" as a
> > rule and make ethtool_get_stats() a wrapper for ethtool_get_stats2() to
> > avoid code duplication (or perhaps a use fall-through in the switch). It
> > would also allow drivers to provide only one of the callbacks.
> 
> Yes, but that would require changing all drivers at once, and would make backporting
> and out-of-tree drivers harder to manage.  I had low hopes that this feature would
> make it upstream, so I didn't want to propose any large changes up front.

I don't think so. What I mean is:

(a) driver implements ->get_ethtool_stats2() callback; then we use it
    for GSTATS2
(b) driver does not implement get_ethtool_stats2() but implements
    ->get_ethtool_stats(); then we call for GSTATS2 if level is zero,
    otherwise GSTATS2 returns -EINVAL

and GSTATS is always translated to GSTATS2 with level 0, either by
defining ethtool_get_stats() as a wrapper or by fall-through in the
switch statement.

This way, most drivers could be left untouched and only those which
would implement non-default levels would provide ->get_ethtool_stats2()
callback instead of ->get_ethtool_stats().

Michal Kubecek
Ben Greear March 20, 2018, 6:29 p.m. UTC | #6
On 03/20/2018 11:24 AM, Michal Kubecek wrote:
> On Tue, Mar 20, 2018 at 08:39:33AM -0700, Ben Greear wrote:
>> On 03/20/2018 03:37 AM, Michal Kubecek wrote:
>>>
>>> IMHO it would be more practical to set "0 means same as GSTATS" as a
>>> rule and make ethtool_get_stats() a wrapper for ethtool_get_stats2() to
>>> avoid code duplication (or perhaps a use fall-through in the switch). It
>>> would also allow drivers to provide only one of the callbacks.
>>
>> Yes, but that would require changing all drivers at once, and would make backporting
>> and out-of-tree drivers harder to manage.  I had low hopes that this feature would
>> make it upstream, so I didn't want to propose any large changes up front.
>
> I don't think so. What I mean is:
>
> (a) driver implements ->get_ethtool_stats2() callback; then we use it
>     for GSTATS2
> (b) driver does not implement get_ethtool_stats2() but implements
>     ->get_ethtool_stats(); then we call for GSTATS2 if level is zero,
>     otherwise GSTATS2 returns -EINVAL
>
> and GSTATS is always translated to GSTATS2 with level 0, either by
> defining ethtool_get_stats() as a wrapper or by fall-through in the
> switch statement.
>
> This way, most drivers could be left untouched and only those which
> would implement non-default levels would provide ->get_ethtool_stats2()
> callback instead of ->get_ethtool_stats().

OK, that makes sense.  I'll wait on feedback from the flags or #defined levels
and re-spin the patch accordingly.

Thanks,
Ben

Patch
diff mbox

diff --git a/drivers/net/wireless/ath/ath10k/debug.c b/drivers/net/wireless/ath/ath10k/debug.c
index 65e0a33..2545c24 100644
--- a/drivers/net/wireless/ath/ath10k/debug.c
+++ b/drivers/net/wireless/ath/ath10k/debug.c
@@ -2389,9 +2389,9 @@  int ath10k_debug_get_et_sset_count(struct ieee80211_hw *hw,
 	return 0;
 }
 
-void ath10k_debug_get_et_stats(struct ieee80211_hw *hw,
-			       struct ieee80211_vif *vif,
-			       struct ethtool_stats *stats, u64 *data)
+void ath10k_debug_get_et_stats2(struct ieee80211_hw *hw,
+				struct ieee80211_vif *vif,
+				struct ethtool_stats *stats, u64 *data, u32 level)
 {
 	struct ath10k *ar = hw->priv;
 	static const struct ath10k_fw_stats_pdev zero_stats = {};
@@ -2401,6 +2401,9 @@  void ath10k_debug_get_et_stats(struct ieee80211_hw *hw,
 
 	mutex_lock(&ar->conf_mutex);
 
+	if (level && level < 5)
+		goto skip_query_fw_stats;
+
 	if (ar->state == ATH10K_STATE_ON) {
 		ath10k_refresh_target_regs(ar); /* Request some CT FW stats. */
 		ret = ath10k_debug_fw_stats_request(ar);
@@ -2412,6 +2415,7 @@  void ath10k_debug_get_et_stats(struct ieee80211_hw *hw,
 		}
 	}
 
+skip_query_fw_stats:
 	pdev_stats = list_first_entry_or_null(&ar->debug.fw_stats.pdevs,
 					      struct ath10k_fw_stats_pdev,
 					      list);
@@ -2497,6 +2501,14 @@  void ath10k_debug_get_et_stats(struct ieee80211_hw *hw,
 	WARN_ON(i != ATH10K_SSTATS_LEN);
 }
 
+void ath10k_debug_get_et_stats(struct ieee80211_hw *hw,
+                              struct ieee80211_vif *vif,
+                              struct ethtool_stats *stats, u64 *data)
+{
+       ath10k_debug_get_et_stats2(hw, vif, stats, data, 0);
+}
+
+
 static const struct file_operations fops_fw_dbglog = {
 	.read = ath10k_read_fw_dbglog,
 	.write = ath10k_write_fw_dbglog,
diff --git a/drivers/net/wireless/ath/ath10k/debug.h b/drivers/net/wireless/ath/ath10k/debug.h
index 74d1728..f33c88f 100644
--- a/drivers/net/wireless/ath/ath10k/debug.h
+++ b/drivers/net/wireless/ath/ath10k/debug.h
@@ -108,6 +108,9 @@  int ath10k_debug_get_et_sset_count(struct ieee80211_hw *hw,
 void ath10k_debug_get_et_stats(struct ieee80211_hw *hw,
 			       struct ieee80211_vif *vif,
 			       struct ethtool_stats *stats, u64 *data);
+void ath10k_debug_get_et_stats2(struct ieee80211_hw *hw,
+				struct ieee80211_vif *vif,
+				struct ethtool_stats *stats, u64 *data, u32 level);
 
 static inline u64 ath10k_debug_get_fw_dbglog_mask(struct ath10k *ar)
 {
diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c
index e962c0e..eed0a9f 100644
--- a/drivers/net/wireless/ath/ath10k/mac.c
+++ b/drivers/net/wireless/ath/ath10k/mac.c
@@ -8472,6 +8472,9 @@  static const struct ieee80211_ops ath10k_ops = {
 	.ampdu_action			= ath10k_ampdu_action,
 	.get_et_sset_count		= ath10k_debug_get_et_sset_count,
 	.get_et_stats			= ath10k_debug_get_et_stats,
+#ifdef MAC80211_HAS_ET_STATS2
+	.get_et_stats2			= ath10k_debug_get_et_stats2,
+#endif
 	.get_et_strings			= ath10k_debug_get_et_strings,
 	.add_chanctx			= ath10k_mac_op_add_chanctx,
 	.remove_chanctx			= ath10k_mac_op_remove_chanctx,
diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 83cc986..9745175 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -221,6 +221,14 @@  bool ethtool_convert_link_mode_to_legacy_u32(u32 *legacy_u32,
  * @get_ethtool_stats: Return extended statistics about the device.
  *	This is only useful if the device maintains statistics not
  *	included in &struct rtnl_link_stats64.
+ * @get_ethtool_stats2: Return extended statistics about the device.
+ *	This is only useful if the device maintains statistics not
+ *	included in &struct rtnl_link_stats64.
+ *      Takes a 'level' argument:  0 means all (same as get_ethtool_stats),
+ *      otherwise 1 is less than 10 (driver specific).
+ *      Same number of stats will be returned, but some of them might
+ *      not be as accurate/refreshed.  This is to allow not querying
+ *      firmware or other expensive-to-read stats, for instance.
  * @begin: Function to be called before any other operation.  Returns a
  *	negative error code or zero.
  * @complete: Function to be called after any other operation except
@@ -333,6 +341,8 @@  struct ethtool_ops {
 	int	(*set_phys_id)(struct net_device *, enum ethtool_phys_id_state);
 	void	(*get_ethtool_stats)(struct net_device *,
 				     struct ethtool_stats *, u64 *);
+	void	(*get_ethtool_stats2)(struct net_device *,
+				      struct ethtool_stats *, u64 *, u32 level);
 	int	(*begin)(struct net_device *);
 	void	(*complete)(struct net_device *);
 	u32	(*get_priv_flags)(struct net_device *);
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index bd6b723..5e99ece 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -3336,6 +3336,8 @@  enum ieee80211_reconfig_type {
  *
  * @get_et_stats:  Ethtool API to get a set of u64 stats.
  *
+ * @get_et_stats2:  Ethtool API to get a set of u64 stats, with level specified.
+ *
  * @get_et_strings:  Ethtool API to get a set of strings to describe stats
  *	and perhaps other supported types of ethtool data-sets.
  *
@@ -3664,6 +3666,10 @@  struct ieee80211_ops {
 	void	(*get_et_stats)(struct ieee80211_hw *hw,
 				struct ieee80211_vif *vif,
 				struct ethtool_stats *stats, u64 *data);
+#define MAC80211_HAS_ET_STATS2 /* Make it easier for backporting drivers. */
+	void	(*get_et_stats2)(struct ieee80211_hw *hw,
+				 struct ieee80211_vif *vif,
+				 struct ethtool_stats *stats, u64 *data, u32 level);
 	void	(*get_et_strings)(struct ieee80211_hw *hw,
 				  struct ieee80211_vif *vif,
 				  u32 sset, u8 *data);
diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index f6da73a..cf1b86f 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -1331,6 +1331,10 @@  struct ethtool_per_queue_op {
 #define ETHTOOL_PHY_GTUNABLE	0x0000004e /* Get PHY tunable configuration */
 #define ETHTOOL_PHY_STUNABLE	0x0000004f /* Set PHY tunable configuration */
 
+#define ETHTOOL_GSTATS2		0x0000ff01 /* get NIC-specific statistics
+					    * with ability to specify level
+					    */
+
 /* compatibility with older code */
 #define SPARC_ETH_GSET		ETHTOOL_GSET
 #define SPARC_ETH_SSET		ETHTOOL_SSET
diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index 674b6c9..d3b709f 100644
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -1947,6 +1947,54 @@  static int ethtool_get_stats(struct net_device *dev, void __user *useraddr)
 	return ret;
 }
 
+static int ethtool_get_stats2(struct net_device *dev, void __user *useraddr)
+{
+	struct ethtool_stats stats;
+	const struct ethtool_ops *ops = dev->ethtool_ops;
+	u64 *data;
+	int ret, n_stats;
+	u32 stats_level = 0;
+
+	if (!ops->get_ethtool_stats2 || !ops->get_sset_count)
+		return -EOPNOTSUPP;
+
+	n_stats = ops->get_sset_count(dev, ETH_SS_STATS);
+	if (n_stats < 0)
+		return n_stats;
+	if (n_stats > S32_MAX / sizeof(u64))
+		return -ENOMEM;
+	WARN_ON_ONCE(!n_stats);
+	if (copy_from_user(&stats, useraddr, sizeof(stats)))
+		return -EFAULT;
+
+	/* User can specify the level of stats to query.  How the
+	 * level value is used is up to the driver, but in general,
+	 * 0 means 'all', 1 means least, and higher means more.
+	 * The idea is that some stats may be expensive to query, so user
+	 * space could just ask for the cheap ones...
+	 */
+	stats_level = stats.n_stats;
+
+	stats.n_stats = n_stats;
+	data = vzalloc(n_stats * sizeof(u64));
+	if (n_stats && !data)
+		return -ENOMEM;
+
+	ops->get_ethtool_stats2(dev, &stats, data, stats_level);
+
+	ret = -EFAULT;
+	if (copy_to_user(useraddr, &stats, sizeof(stats)))
+		goto out;
+	useraddr += sizeof(stats);
+	if (n_stats && copy_to_user(useraddr, data, n_stats * sizeof(u64)))
+		goto out;
+	ret = 0;
+
+ out:
+	vfree(data);
+	return ret;
+}
+
 static int ethtool_get_phy_stats(struct net_device *dev, void __user *useraddr)
 {
 	struct ethtool_stats stats;
@@ -2552,6 +2600,7 @@  int dev_ethtool(struct net *net, struct ifreq *ifr)
 	case ETHTOOL_GSSET_INFO:
 	case ETHTOOL_GSTRINGS:
 	case ETHTOOL_GSTATS:
+	case ETHTOOL_GSTATS2:
 	case ETHTOOL_GPHYSTATS:
 	case ETHTOOL_GTSO:
 	case ETHTOOL_GPERMADDR:
@@ -2662,6 +2711,9 @@  int dev_ethtool(struct net *net, struct ifreq *ifr)
 	case ETHTOOL_GSTATS:
 		rc = ethtool_get_stats(dev, useraddr);
 		break;
+	case ETHTOOL_GSTATS2:
+		rc = ethtool_get_stats2(dev, useraddr);
+		break;
 	case ETHTOOL_GPERMADDR:
 		rc = ethtool_get_perm_addr(dev, useraddr);
 		break;
diff --git a/net/mac80211/driver-ops.h b/net/mac80211/driver-ops.h
index c0a52a0..55dbdc7 100644
--- a/net/mac80211/driver-ops.h
+++ b/net/mac80211/driver-ops.h
@@ -79,10 +79,15 @@  static inline void drv_get_et_strings(struct ieee80211_sub_if_data *sdata,
 
 static inline void drv_get_et_stats(struct ieee80211_sub_if_data *sdata,
 				    struct ethtool_stats *stats,
-				    u64 *data)
+				    u64 *data, u32 level)
 {
 	struct ieee80211_local *local = sdata->local;
-	if (local->ops->get_et_stats) {
+	if (local->ops->get_et_stats2) {
+		trace_drv_get_et_stats(local);
+		local->ops->get_et_stats2(&local->hw, &sdata->vif, stats, data, level);
+		trace_drv_return_void(local);
+	}
+	else if (local->ops->get_et_stats) {
 		trace_drv_get_et_stats(local);
 		local->ops->get_et_stats(&local->hw, &sdata->vif, stats, data);
 		trace_drv_return_void(local);
diff --git a/net/mac80211/ethtool.c b/net/mac80211/ethtool.c
index dc6f76f..e7b012a 100644
--- a/net/mac80211/ethtool.c
+++ b/net/mac80211/ethtool.c
@@ -80,9 +80,9 @@  static int ieee80211_get_sset_count(struct net_device *dev, int sset)
 	return rv;
 }
 
-static void ieee80211_get_stats(struct net_device *dev,
-				struct ethtool_stats *stats,
-				u64 *data)
+static void ieee80211_get_stats2(struct net_device *dev,
+				 struct ethtool_stats *stats,
+				 u64 *data, u32 level)
 {
 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 	struct ieee80211_chanctx_conf *chanctx_conf;
@@ -259,7 +259,14 @@  static void ieee80211_get_stats(struct net_device *dev,
 	if (WARN_ON(i != STA_STATS_LEN))
 		return;
 
-	drv_get_et_stats(sdata, stats, &(data[STA_STATS_LEN]));
+	drv_get_et_stats(sdata, stats, &(data[STA_STATS_LEN]), level);
+}
+
+static void ieee80211_get_stats(struct net_device *dev,
+				struct ethtool_stats *stats,
+				u64 *data)
+{
+	ieee80211_get_stats2(dev, stats, data, 0);
 }
 
 static void ieee80211_get_strings(struct net_device *dev, u32 sset, u8 *data)
@@ -298,5 +305,6 @@  const struct ethtool_ops ieee80211_ethtool_ops = {
 	.set_ringparam = ieee80211_set_ringparam,
 	.get_strings = ieee80211_get_strings,
 	.get_ethtool_stats = ieee80211_get_stats,
+	.get_ethtool_stats2 = ieee80211_get_stats2,
 	.get_sset_count = ieee80211_get_sset_count,
 };