[PATCH 21/25] xfrm: Replace hrtimer tasklet with softirq hrtimer

[PATCH 21/25] xfrm: Replace hrtimer tasklet with softirq hrtimer

[Anna-Maria Gleixner]

[-- Attachment #1: xfrm_Replace_hrtimer_tasklet_with_softirq_hrtimer.patch --]
[-- Type: text/plain, Size: 4743 bytes --]

From: Thomas Gleixner <tglx@linutronix.de>

Switch the timer to CLOCK_MONOTONIC_SOFT, which executed the timer
callback in softirq context and remove the hrtimer_tasklet.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org

---
 include/net/xfrm.h    |    2 +-
 net/xfrm/xfrm_state.c |   29 +++++++++++++++++------------
 2 files changed, 18 insertions(+), 13 deletions(-)

--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -213,7 +213,7 @@ struct xfrm_state {
 	struct xfrm_stats	stats;
 
 	struct xfrm_lifetime_cur curlft;
-	struct tasklet_hrtimer	mtimer;
+	struct hrtimer		mtimer;
 
 	struct xfrm_state_offload xso;
 
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -418,7 +418,7 @@ static void xfrm_put_mode(struct xfrm_mo
 
 static void xfrm_state_gc_destroy(struct xfrm_state *x)
 {
-	tasklet_hrtimer_cancel(&x->mtimer);
+	hrtimer_cancel(&x->mtimer);
 	del_timer_sync(&x->rtimer);
 	kfree(x->aead);
 	kfree(x->aalg);
@@ -463,8 +463,8 @@ static void xfrm_state_gc_task(struct wo
 
 static enum hrtimer_restart xfrm_timer_handler(struct hrtimer *me)
 {
-	struct tasklet_hrtimer *thr = container_of(me, struct tasklet_hrtimer, timer);
-	struct xfrm_state *x = container_of(thr, struct xfrm_state, mtimer);
+	struct xfrm_state *x = container_of(me, struct xfrm_state, mtimer);
+	enum hrtimer_restart ret = HRTIMER_NORESTART;
 	unsigned long now = get_seconds();
 	long next = LONG_MAX;
 	int warn = 0;
@@ -528,7 +528,8 @@ static enum hrtimer_restart xfrm_timer_h
 		km_state_expired(x, 0, 0);
 resched:
 	if (next != LONG_MAX) {
-		tasklet_hrtimer_start(&x->mtimer, ktime_set(next, 0), HRTIMER_MODE_REL);
+		hrtimer_forward_now(&x->mtimer, ktime_set(next, 0));
+		ret = HRTIMER_RESTART;
 	}
 
 	goto out;
@@ -545,7 +546,7 @@ static enum hrtimer_restart xfrm_timer_h
 
 out:
 	spin_unlock(&x->lock);
-	return HRTIMER_NORESTART;
+	return ret;
 }
 
 static void xfrm_replay_timer_handler(unsigned long data);
@@ -564,8 +565,8 @@ struct xfrm_state *xfrm_state_alloc(stru
 		INIT_HLIST_NODE(&x->bydst);
 		INIT_HLIST_NODE(&x->bysrc);
 		INIT_HLIST_NODE(&x->byspi);
-		tasklet_hrtimer_init(&x->mtimer, xfrm_timer_handler,
-					CLOCK_BOOTTIME, HRTIMER_MODE_ABS);
+		hrtimer_init(&x->mtimer, CLOCK_BOOTTIME_SOFT, HRTIMER_MODE_ABS);
+		x->mtimer.function = xfrm_timer_handler;
 		setup_timer(&x->rtimer, xfrm_replay_timer_handler,
 				(unsigned long)x);
 		x->curlft.add_time = get_seconds();
@@ -1021,7 +1022,9 @@ xfrm_state_find(const xfrm_address_t *da
 				hlist_add_head_rcu(&x->byspi, net->xfrm.state_byspi + h);
 			}
 			x->lft.hard_add_expires_seconds = net->xfrm.sysctl_acq_expires;
-			tasklet_hrtimer_start(&x->mtimer, ktime_set(net->xfrm.sysctl_acq_expires, 0), HRTIMER_MODE_REL);
+			hrtimer_start(&x->mtimer,
+				      ktime_set(net->xfrm.sysctl_acq_expires, 0),
+				      HRTIMER_MODE_REL);
 			net->xfrm.state_num++;
 			xfrm_hash_grow_check(net, x->bydst.next != NULL);
 			spin_unlock_bh(&net->xfrm.xfrm_state_lock);
@@ -1132,7 +1135,7 @@ static void __xfrm_state_insert(struct x
 		hlist_add_head_rcu(&x->byspi, net->xfrm.state_byspi + h);
 	}
 
-	tasklet_hrtimer_start(&x->mtimer, ktime_set(1, 0), HRTIMER_MODE_REL);
+	hrtimer_start(&x->mtimer, ktime_set(1, 0), HRTIMER_MODE_REL);
 	if (x->replay_maxage)
 		mod_timer(&x->rtimer, jiffies + x->replay_maxage);
 
@@ -1236,7 +1239,9 @@ static struct xfrm_state *__find_acq_cor
 		x->mark.m = m->m;
 		x->lft.hard_add_expires_seconds = net->xfrm.sysctl_acq_expires;
 		xfrm_state_hold(x);
-		tasklet_hrtimer_start(&x->mtimer, ktime_set(net->xfrm.sysctl_acq_expires, 0), HRTIMER_MODE_REL);
+		hrtimer_start(&x->mtimer,
+			      ktime_set(net->xfrm.sysctl_acq_expires, 0),
+			      HRTIMER_MODE_REL);
 		list_add(&x->km.all, &net->xfrm.state_all);
 		hlist_add_head_rcu(&x->bydst, net->xfrm.state_bydst + h);
 		h = xfrm_src_hash(net, daddr, saddr, family);
@@ -1535,7 +1540,7 @@ int xfrm_state_update(struct xfrm_state
 		memcpy(&x1->lft, &x->lft, sizeof(x1->lft));
 		x1->km.dying = 0;
 
-		tasklet_hrtimer_start(&x1->mtimer, ktime_set(1, 0), HRTIMER_MODE_REL);
+		hrtimer_start(&x1->mtimer, ktime_set(1, 0), HRTIMER_MODE_REL);
 		if (x1->curlft.use_time)
 			xfrm_state_check_expire(x1);
 
@@ -1559,7 +1564,7 @@ int xfrm_state_check_expire(struct xfrm_
 	if (x->curlft.bytes >= x->lft.hard_byte_limit ||
 	    x->curlft.packets >= x->lft.hard_packet_limit) {
 		x->km.state = XFRM_STATE_EXPIRED;
-		tasklet_hrtimer_start(&x->mtimer, 0, HRTIMER_MODE_REL);
+		hrtimer_start(&x->mtimer, 0, HRTIMER_MODE_REL);
 		return -EINVAL;
 	}
 

[PATCH 24/25] net/cdc_ncm: Replace tasklet with softirq hrtimer

[Anna-Maria Gleixner]

[-- Attachment #1: netcdc_ncm_Replace_tasklet_with_softirq_hrtimer.patch --]
[-- Type: text/plain, Size: 3486 bytes --]

From: Thomas Gleixner <tglx@linutronix.de>

The bh tasklet is used in invoke the hrtimer (cdc_ncm_tx_timer_cb) in
softirq context. This can be also achieved without the tasklet but with
CLOCK_MONOTONIC_SOFT as hrtimer base.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Oliver Neukum <oliver@neukum.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Cc: netdev@vger.kernel.org
---
 drivers/net/usb/cdc_ncm.c   |   37 ++++++++++++++++---------------------
 include/linux/usb/cdc_ncm.h |    2 +-
 2 files changed, 17 insertions(+), 22 deletions(-)

--- a/drivers/net/usb/cdc_ncm.c
+++ b/drivers/net/usb/cdc_ncm.c
@@ -61,7 +61,6 @@ static bool prefer_mbim;
 module_param(prefer_mbim, bool, S_IRUGO | S_IWUSR);
 MODULE_PARM_DESC(prefer_mbim, "Prefer MBIM setting on dual NCM/MBIM functions");
 
-static void cdc_ncm_txpath_bh(unsigned long param);
 static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx);
 static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *hr_timer);
 static struct usb_driver cdc_ncm_driver;
@@ -777,10 +776,9 @@ int cdc_ncm_bind_common(struct usbnet *d
 	if (!ctx)
 		return -ENOMEM;
 
-	hrtimer_init(&ctx->tx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	hrtimer_init(&ctx->tx_timer, CLOCK_MONOTONIC_SOFT, HRTIMER_MODE_REL);
 	ctx->tx_timer.function = &cdc_ncm_tx_timer_cb;
-	ctx->bh.data = (unsigned long)dev;
-	ctx->bh.func = cdc_ncm_txpath_bh;
+	ctx->usbnet = dev;
 	atomic_set(&ctx->stop, 0);
 	spin_lock_init(&ctx->mtx);
 
@@ -967,10 +965,7 @@ void cdc_ncm_unbind(struct usbnet *dev,
 
 	atomic_set(&ctx->stop, 1);
 
-	if (hrtimer_active(&ctx->tx_timer))
-		hrtimer_cancel(&ctx->tx_timer);
-
-	tasklet_kill(&ctx->bh);
+	hrtimer_cancel(&ctx->tx_timer);
 
 	/* handle devices with combined control and data interface */
 	if (ctx->control == ctx->data)
@@ -1348,20 +1343,9 @@ static void cdc_ncm_tx_timeout_start(str
 				HRTIMER_MODE_REL);
 }
 
-static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *timer)
+static void cdc_ncm_txpath_bh(struct cdc_ncm_ctx *ctx)
 {
-	struct cdc_ncm_ctx *ctx =
-			container_of(timer, struct cdc_ncm_ctx, tx_timer);
-
-	if (!atomic_read(&ctx->stop))
-		tasklet_schedule(&ctx->bh);
-	return HRTIMER_NORESTART;
-}
-
-static void cdc_ncm_txpath_bh(unsigned long param)
-{
-	struct usbnet *dev = (struct usbnet *)param;
-	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
+	struct usbnet *dev = ctx->usbnet;
 
 	spin_lock_bh(&ctx->mtx);
 	if (ctx->tx_timer_pending != 0) {
@@ -1379,6 +1363,17 @@ static void cdc_ncm_txpath_bh(unsigned l
 	}
 }
 
+static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *timer)
+{
+	struct cdc_ncm_ctx *ctx =
+			container_of(timer, struct cdc_ncm_ctx, tx_timer);
+
+	if (!atomic_read(&ctx->stop))
+		cdc_ncm_txpath_bh(ctx);
+
+	return HRTIMER_NORESTART;
+}
+
 struct sk_buff *
 cdc_ncm_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
 {
--- a/include/linux/usb/cdc_ncm.h
+++ b/include/linux/usb/cdc_ncm.h
@@ -92,7 +92,6 @@
 struct cdc_ncm_ctx {
 	struct usb_cdc_ncm_ntb_parameters ncm_parm;
 	struct hrtimer tx_timer;
-	struct tasklet_struct bh;
 
 	const struct usb_cdc_ncm_desc *func_desc;
 	const struct usb_cdc_mbim_desc *mbim_desc;
@@ -101,6 +100,7 @@ struct cdc_ncm_ctx {
 
 	struct usb_interface *control;
 	struct usb_interface *data;
+	struct usbnet *usbnet;
 
 	struct sk_buff *tx_curr_skb;
 	struct sk_buff *tx_rem_skb;

Re: [PATCH 24/25] net/cdc_ncm: Replace tasklet with softirq hrtimer

[Greg Kroah-Hartman]

On Thu, Aug 31, 2017 at 12:23:46PM -0000, Anna-Maria Gleixner wrote:
> From: Thomas Gleixner <tglx@linutronix.de>
> 
> The bh tasklet is used in invoke the hrtimer (cdc_ncm_tx_timer_cb) in
> softirq context. This can be also achieved without the tasklet but with
> CLOCK_MONOTONIC_SOFT as hrtimer base.
> 
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
> Cc: Oliver Neukum <oliver@neukum.org>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: linux-usb@vger.kernel.org
> Cc: netdev@vger.kernel.org


Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Re: [PATCH 24/25] net/cdc_ncm: Replace tasklet with softirq hrtimer

[Bjørn Mork]

Anna-Maria Gleixner <anna-maria@linutronix.de> writes:

> From: Thomas Gleixner <tglx@linutronix.de>
>
> The bh tasklet is used in invoke the hrtimer (cdc_ncm_tx_timer_cb) in
> softirq context. This can be also achieved without the tasklet but with
> CLOCK_MONOTONIC_SOFT as hrtimer base.
>
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
> Cc: Oliver Neukum <oliver@neukum.org>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: linux-usb@vger.kernel.org
> Cc: netdev@vger.kernel.org
> ---
>  drivers/net/usb/cdc_ncm.c   |   37 ++++++++++++++++---------------------
>  include/linux/usb/cdc_ncm.h |    2 +-
>  2 files changed, 17 insertions(+), 22 deletions(-)
>
> --- a/drivers/net/usb/cdc_ncm.c
> +++ b/drivers/net/usb/cdc_ncm.c
> @@ -61,7 +61,6 @@ static bool prefer_mbim;
>  module_param(prefer_mbim, bool, S_IRUGO | S_IWUSR);
>  MODULE_PARM_DESC(prefer_mbim, "Prefer MBIM setting on dual NCM/MBIM functions");
>  
> -static void cdc_ncm_txpath_bh(unsigned long param);
>  static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx);
>  static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *hr_timer);
>  static struct usb_driver cdc_ncm_driver;
> @@ -777,10 +776,9 @@ int cdc_ncm_bind_common(struct usbnet *d
>  	if (!ctx)
>  		return -ENOMEM;
>  
> -	hrtimer_init(&ctx->tx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
> +	hrtimer_init(&ctx->tx_timer, CLOCK_MONOTONIC_SOFT, HRTIMER_MODE_REL);
>  	ctx->tx_timer.function = &cdc_ncm_tx_timer_cb;
> -	ctx->bh.data = (unsigned long)dev;
> -	ctx->bh.func = cdc_ncm_txpath_bh;
> +	ctx->usbnet = dev;
>  	atomic_set(&ctx->stop, 0);
>  	spin_lock_init(&ctx->mtx);
>  
> @@ -967,10 +965,7 @@ void cdc_ncm_unbind(struct usbnet *dev,
>  
>  	atomic_set(&ctx->stop, 1);
>  
> -	if (hrtimer_active(&ctx->tx_timer))
> -		hrtimer_cancel(&ctx->tx_timer);
> -
> -	tasklet_kill(&ctx->bh);
> +	hrtimer_cancel(&ctx->tx_timer);
>  
>  	/* handle devices with combined control and data interface */
>  	if (ctx->control == ctx->data)
> @@ -1348,20 +1343,9 @@ static void cdc_ncm_tx_timeout_start(str
>  				HRTIMER_MODE_REL);
>  }
>  
> -static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *timer)
> +static void cdc_ncm_txpath_bh(struct cdc_ncm_ctx *ctx)
>  {
> -	struct cdc_ncm_ctx *ctx =
> -			container_of(timer, struct cdc_ncm_ctx, tx_timer);
> -
> -	if (!atomic_read(&ctx->stop))
> -		tasklet_schedule(&ctx->bh);
> -	return HRTIMER_NORESTART;
> -}
> -
> -static void cdc_ncm_txpath_bh(unsigned long param)
> -{
> -	struct usbnet *dev = (struct usbnet *)param;
> -	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
> +	struct usbnet *dev = ctx->usbnet;
>  
>  	spin_lock_bh(&ctx->mtx);
>  	if (ctx->tx_timer_pending != 0) {
> @@ -1379,6 +1363,17 @@ static void cdc_ncm_txpath_bh(unsigned l
>  	}
>  }
>  
> +static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *timer)
> +{
> +	struct cdc_ncm_ctx *ctx =
> +			container_of(timer, struct cdc_ncm_ctx, tx_timer);
> +
> +	if (!atomic_read(&ctx->stop))
> +		cdc_ncm_txpath_bh(ctx);
> +
> +	return HRTIMER_NORESTART;
> +}
> +
>  struct sk_buff *
>  cdc_ncm_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
>  {
> --- a/include/linux/usb/cdc_ncm.h
> +++ b/include/linux/usb/cdc_ncm.h
> @@ -92,7 +92,6 @@
>  struct cdc_ncm_ctx {
>  	struct usb_cdc_ncm_ntb_parameters ncm_parm;
>  	struct hrtimer tx_timer;
> -	struct tasklet_struct bh;
>  
>  	const struct usb_cdc_ncm_desc *func_desc;
>  	const struct usb_cdc_mbim_desc *mbim_desc;
> @@ -101,6 +100,7 @@ struct cdc_ncm_ctx {
>  
>  	struct usb_interface *control;
>  	struct usb_interface *data;
> +	struct usbnet *usbnet;
>  
>  	struct sk_buff *tx_curr_skb;
>  	struct sk_buff *tx_rem_skb;




I believe the struct usbnet pointer is redundant.  We already have lots
of pointers back and forth here.  This should work, but is not tested:

	struct usbnet *dev = usb_get_intfdata(ctx->control):




Bjørn

[PATCH 24/25 v2] net/cdc_ncm: Replace tasklet with softirq hrtimer

[Sebastian Andrzej Siewior]

From: Thomas Gleixner <tglx@linutronix.de>

The bh tasklet is used in invoke the hrtimer (cdc_ncm_tx_timer_cb) in
softirq context. This can be also achieved without the tasklet but with
CLOCK_MONOTONIC_SOFT as hrtimer base.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Oliver Neukum <oliver@neukum.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Cc: netdev@vger.kernel.org
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bigeasy: using usb_get_intfdata() as suggested by Bjørn Mork]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
On 2017-08-31 15:57:04 [+0200], Bjørn Mork wrote:
> I believe the struct usbnet pointer is redundant.  We already have lots
> of pointers back and forth here.  This should work, but is not tested:
> 
> 	struct usbnet *dev = usb_get_intfdata(ctx->control):

I think so, too. Still untested as I don't have a working gadget around.

v1…v2: Updated as suggested by Bjørn and added Greg's Acked-by.

 drivers/net/usb/cdc_ncm.c   | 36 +++++++++++++++---------------------
 include/linux/usb/cdc_ncm.h |  1 -
 2 files changed, 15 insertions(+), 22 deletions(-)

diff --git a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c
index 8f572b9f3625..42f7bd90e6a4 100644
--- a/drivers/net/usb/cdc_ncm.c
+++ b/drivers/net/usb/cdc_ncm.c
@@ -61,7 +61,6 @@ static bool prefer_mbim;
 module_param(prefer_mbim, bool, S_IRUGO | S_IWUSR);
 MODULE_PARM_DESC(prefer_mbim, "Prefer MBIM setting on dual NCM/MBIM functions");
 
-static void cdc_ncm_txpath_bh(unsigned long param);
 static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx);
 static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *hr_timer);
 static struct usb_driver cdc_ncm_driver;
@@ -777,10 +776,8 @@ int cdc_ncm_bind_common(struct usbnet *dev, struct usb_interface *intf, u8 data_
 	if (!ctx)
 		return -ENOMEM;
 
-	hrtimer_init(&ctx->tx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	hrtimer_init(&ctx->tx_timer, CLOCK_MONOTONIC_SOFT, HRTIMER_MODE_REL);
 	ctx->tx_timer.function = &cdc_ncm_tx_timer_cb;
-	ctx->bh.data = (unsigned long)dev;
-	ctx->bh.func = cdc_ncm_txpath_bh;
 	atomic_set(&ctx->stop, 0);
 	spin_lock_init(&ctx->mtx);
 
@@ -967,10 +964,7 @@ void cdc_ncm_unbind(struct usbnet *dev, struct usb_interface *intf)
 
 	atomic_set(&ctx->stop, 1);
 
-	if (hrtimer_active(&ctx->tx_timer))
-		hrtimer_cancel(&ctx->tx_timer);
-
-	tasklet_kill(&ctx->bh);
+	hrtimer_cancel(&ctx->tx_timer);
 
 	/* handle devices with combined control and data interface */
 	if (ctx->control == ctx->data)
@@ -1348,20 +1342,9 @@ static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx)
 				HRTIMER_MODE_REL);
 }
 
-static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *timer)
+static void cdc_ncm_txpath_bh(struct cdc_ncm_ctx *ctx)
 {
-	struct cdc_ncm_ctx *ctx =
-			container_of(timer, struct cdc_ncm_ctx, tx_timer);
-
-	if (!atomic_read(&ctx->stop))
-		tasklet_schedule(&ctx->bh);
-	return HRTIMER_NORESTART;
-}
-
-static void cdc_ncm_txpath_bh(unsigned long param)
-{
-	struct usbnet *dev = (struct usbnet *)param;
-	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
+	struct usbnet *dev = usb_get_intfdata(ctx->control);
 
 	spin_lock_bh(&ctx->mtx);
 	if (ctx->tx_timer_pending != 0) {
@@ -1379,6 +1362,17 @@ static void cdc_ncm_txpath_bh(unsigned long param)
 	}
 }
 
+static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *timer)
+{
+	struct cdc_ncm_ctx *ctx =
+			container_of(timer, struct cdc_ncm_ctx, tx_timer);
+
+	if (!atomic_read(&ctx->stop))
+		cdc_ncm_txpath_bh(ctx);
+
+	return HRTIMER_NORESTART;
+}
+
 struct sk_buff *
 cdc_ncm_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
 {
diff --git a/include/linux/usb/cdc_ncm.h b/include/linux/usb/cdc_ncm.h
index 1a59699cf82a..62b506fddf8d 100644
--- a/include/linux/usb/cdc_ncm.h
+++ b/include/linux/usb/cdc_ncm.h
@@ -92,7 +92,6 @@
 struct cdc_ncm_ctx {
 	struct usb_cdc_ncm_ntb_parameters ncm_parm;
 	struct hrtimer tx_timer;
-	struct tasklet_struct bh;
 
 	const struct usb_cdc_ncm_desc *func_desc;
 	const struct usb_cdc_mbim_desc *mbim_desc;
-- 
2.14.1