diff mbox series

[v2,net-next,05/15] net: sgi: ioc3-eth: allocate space for desc rings only once

Message ID 20190829155014.9229-6-tbogendoerfer@suse.de (mailing list archive)
State Superseded
Headers show
Series ioc3-eth improvements | expand

Commit Message

Thomas Bogendoerfer Aug. 29, 2019, 3:50 p.m. UTC 
Memory for descriptor rings are allocated/freed, when interface is
brought up/down. Since the size of the rings is not changeable by
hardware, we now allocate rings now during probe and free it, when
device is removed.

Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/sgi/ioc3-eth.c | 103 ++++++++++++++++++------------------
 1 file changed, 51 insertions(+), 52 deletions(-)

Comments

Jakub Kicinski Aug. 29, 2019, 9:05 p.m. UTC | #1 
On Thu, 29 Aug 2019 17:50:03 +0200, Thomas Bogendoerfer wrote:
> Memory for descriptor rings are allocated/freed, when interface is
> brought up/down. Since the size of the rings is not changeable by
> hardware, we now allocate rings now during probe and free it, when
> device is removed.
> 
> Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
> ---
>  drivers/net/ethernet/sgi/ioc3-eth.c | 103 ++++++++++++++++++------------------
>  1 file changed, 51 insertions(+), 52 deletions(-)
> 
> diff --git a/drivers/net/ethernet/sgi/ioc3-eth.c b/drivers/net/ethernet/sgi/ioc3-eth.c
> index ba18a53fbbe6..d9d94a55ac34 100644
> --- a/drivers/net/ethernet/sgi/ioc3-eth.c
> +++ b/drivers/net/ethernet/sgi/ioc3-eth.c
> @@ -803,25 +803,17 @@ static void ioc3_free_rings(struct ioc3_private *ip)
>  	struct sk_buff *skb;
>  	int rx_entry, n_entry;
>  
> -	if (ip->txr) {
> -		ioc3_clean_tx_ring(ip);
> -		free_pages((unsigned long)ip->txr, 2);
> -		ip->txr = NULL;
> -	}
> +	ioc3_clean_tx_ring(ip);
>  
> -	if (ip->rxr) {
> -		n_entry = ip->rx_ci;
> -		rx_entry = ip->rx_pi;
> +	n_entry = ip->rx_ci;
> +	rx_entry = ip->rx_pi;
>  
> -		while (n_entry != rx_entry) {
> -			skb = ip->rx_skbs[n_entry];
> -			if (skb)
> -				dev_kfree_skb_any(skb);
> +	while (n_entry != rx_entry) {
> +		skb = ip->rx_skbs[n_entry];
> +		if (skb)
> +			dev_kfree_skb_any(skb);

I think dev_kfree_skb_any() accepts NULL

>  
> -			n_entry = (n_entry + 1) & RX_RING_MASK;
> -		}
> -		free_page((unsigned long)ip->rxr);
> -		ip->rxr = NULL;
> +		n_entry = (n_entry + 1) & RX_RING_MASK;
>  	}
>  }
>  
> @@ -829,49 +821,34 @@ static void ioc3_alloc_rings(struct net_device *dev)
>  {
>  	struct ioc3_private *ip = netdev_priv(dev);
>  	struct ioc3_erxbuf *rxb;
> -	unsigned long *rxr;
>  	int i;
>  
> -	if (!ip->rxr) {
> -		/* Allocate and initialize rx ring.  4kb = 512 entries  */
> -		ip->rxr = (unsigned long *)get_zeroed_page(GFP_ATOMIC);
> -		rxr = ip->rxr;
> -		if (!rxr)
> -			pr_err("%s: get_zeroed_page() failed!\n", __func__);
> -
> -		/* Now the rx buffers.  The RX ring may be larger but
> -		 * we only allocate 16 buffers for now.  Need to tune
> -		 * this for performance and memory later.
> -		 */
> -		for (i = 0; i < RX_BUFFS; i++) {
> -			struct sk_buff *skb;
> +	/* Now the rx buffers.  The RX ring may be larger but
> +	 * we only allocate 16 buffers for now.  Need to tune
> +	 * this for performance and memory later.
> +	 */
> +	for (i = 0; i < RX_BUFFS; i++) {
> +		struct sk_buff *skb;
>  
> -			skb = ioc3_alloc_skb(RX_BUF_ALLOC_SIZE, GFP_ATOMIC);
> -			if (!skb) {
> -				show_free_areas(0, NULL);
> -				continue;
> -			}
> +		skb = ioc3_alloc_skb(RX_BUF_ALLOC_SIZE, GFP_ATOMIC);
> +		if (!skb) {
> +			show_free_areas(0, NULL);
> +			continue;
> +		}
>  
> -			ip->rx_skbs[i] = skb;
> +		ip->rx_skbs[i] = skb;
>  
> -			/* Because we reserve afterwards. */
> -			skb_put(skb, (1664 + RX_OFFSET));
> -			rxb = (struct ioc3_erxbuf *)skb->data;
> -			rxr[i] = cpu_to_be64(ioc3_map(rxb, 1));
> -			skb_reserve(skb, RX_OFFSET);
> -		}
> -		ip->rx_ci = 0;
> -		ip->rx_pi = RX_BUFFS;
> +		/* Because we reserve afterwards. */
> +		skb_put(skb, (1664 + RX_OFFSET));
> +		rxb = (struct ioc3_erxbuf *)skb->data;
> +		ip->rxr[i] = cpu_to_be64(ioc3_map(rxb, 1));
> +		skb_reserve(skb, RX_OFFSET);
>  	}
> +	ip->rx_ci = 0;
> +	ip->rx_pi = RX_BUFFS;
>  
> -	if (!ip->txr) {
> -		/* Allocate and initialize tx rings.  16kb = 128 bufs.  */
> -		ip->txr = (struct ioc3_etxd *)__get_free_pages(GFP_KERNEL, 2);
> -		if (!ip->txr)
> -			pr_err("%s: __get_free_pages() failed!\n", __func__);
> -		ip->tx_pi = 0;
> -		ip->tx_ci = 0;
> -	}
> +	ip->tx_pi = 0;
> +	ip->tx_ci = 0;
>  }
>  
>  static void ioc3_init_rings(struct net_device *dev)
> @@ -1239,6 +1216,23 @@ static int ioc3_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
>  	timer_setup(&ip->ioc3_timer, ioc3_timer, 0);
>  
>  	ioc3_stop(ip);
> +
> +	/* Allocate and rx ring.  4kb = 512 entries  */
> +	ip->rxr = (unsigned long *)get_zeroed_page(GFP_ATOMIC);
> +	if (!ip->rxr) {
> +		pr_err("ioc3-eth: rx ring allocation failed\n");
> +		err = -ENOMEM;
> +		goto out_stop;
> +	}
> +
> +	/* Allocate tx rings.  16kb = 128 bufs.  */
> +	ip->txr = (struct ioc3_etxd *)__get_free_pages(GFP_KERNEL, 2);
> +	if (!ip->txr) {
> +		pr_err("ioc3-eth: tx ring allocation failed\n");
> +		err = -ENOMEM;
> +		goto out_stop;
> +	}

Please just use kcalloc()/kmalloc_array() here, and make sure the flags
are set to GFP_KERNEL whenever possible. Here and in ioc3_alloc_rings()
it looks like GFP_ATOMIC is unnecessary.
Thomas Bogendoerfer Aug. 29, 2019, 10 p.m. UTC | #2 
On Thu, 29 Aug 2019 14:05:37 -0700
Jakub Kicinski <jakub.kicinski@netronome.com> wrote:

> On Thu, 29 Aug 2019 17:50:03 +0200, Thomas Bogendoerfer wrote:
> > +		if (skb)
> > +			dev_kfree_skb_any(skb);
> 
> I think dev_kfree_skb_any() accepts NULL

yes, I'll drop the if

> > +
> > +	/* Allocate and rx ring.  4kb = 512 entries  */
> > +	ip->rxr = (unsigned long *)get_zeroed_page(GFP_ATOMIC);
> > +	if (!ip->rxr) {
> > +		pr_err("ioc3-eth: rx ring allocation failed\n");
> > +		err = -ENOMEM;
> > +		goto out_stop;
> > +	}
> > +
> > +	/* Allocate tx rings.  16kb = 128 bufs.  */
> > +	ip->txr = (struct ioc3_etxd *)__get_free_pages(GFP_KERNEL, 2);
> > +	if (!ip->txr) {
> > +		pr_err("ioc3-eth: tx ring allocation failed\n");
> > +		err = -ENOMEM;
> > +		goto out_stop;
> > +	}
> 
> Please just use kcalloc()/kmalloc_array() here,

both allocation will be replaced in patch 11 with dma_direct_alloc_pages.
So I hope I don't need to change it here.

Out of curiosity does kcalloc/kmalloc_array give me the same guarantees about
alignment ? rx ring needs to be 4KB aligned, tx ring 16KB aligned.

>, and make sure the flags
> are set to GFP_KERNEL whenever possible. Here and in ioc3_alloc_rings()
> it looks like GFP_ATOMIC is unnecessary.

yes, I'll change it

Thomas.
Jakub Kicinski Aug. 29, 2019, 10:05 p.m. UTC | #3 
On Fri, 30 Aug 2019 00:00:58 +0200, Thomas Bogendoerfer wrote:
> On Thu, 29 Aug 2019 14:05:37 -0700
> Jakub Kicinski <jakub.kicinski@netronome.com> wrote:
> 
> > On Thu, 29 Aug 2019 17:50:03 +0200, Thomas Bogendoerfer wrote:  
> > > +		if (skb)
> > > +			dev_kfree_skb_any(skb);  
> > 
> > I think dev_kfree_skb_any() accepts NULL  
> 
> yes, I'll drop the if
> 
> > > +
> > > +	/* Allocate and rx ring.  4kb = 512 entries  */
> > > +	ip->rxr = (unsigned long *)get_zeroed_page(GFP_ATOMIC);
> > > +	if (!ip->rxr) {
> > > +		pr_err("ioc3-eth: rx ring allocation failed\n");
> > > +		err = -ENOMEM;
> > > +		goto out_stop;
> > > +	}
> > > +
> > > +	/* Allocate tx rings.  16kb = 128 bufs.  */
> > > +	ip->txr = (struct ioc3_etxd *)__get_free_pages(GFP_KERNEL, 2);
> > > +	if (!ip->txr) {
> > > +		pr_err("ioc3-eth: tx ring allocation failed\n");
> > > +		err = -ENOMEM;
> > > +		goto out_stop;
> > > +	}  
> > 
> > Please just use kcalloc()/kmalloc_array() here,  
> 
> both allocation will be replaced in patch 11 with dma_direct_alloc_pages.
> So I hope I don't need to change it here.

Ah, missed that!

> Out of curiosity does kcalloc/kmalloc_array give me the same guarantees about
> alignment ? rx ring needs to be 4KB aligned, tx ring 16KB aligned.

I don't think so, actually, I was mostly worried you are passing
address from get_page() into kfree() here ;) But patch 11 cures that,
so that's good, too.

> >, and make sure the flags
> > are set to GFP_KERNEL whenever possible. Here and in ioc3_alloc_rings()
> > it looks like GFP_ATOMIC is unnecessary.  
> 
> yes, I'll change it
Thomas Bogendoerfer Aug. 30, 2019, 8:09 a.m. UTC | #4 
On Thu, 29 Aug 2019 15:05:04 -0700
Jakub Kicinski <jakub.kicinski@netronome.com> wrote:

> On Fri, 30 Aug 2019 00:00:58 +0200, Thomas Bogendoerfer wrote:

> > Out of curiosity does kcalloc/kmalloc_array give me the same guarantees about
> > alignment ? rx ring needs to be 4KB aligned, tx ring 16KB aligned.
> 
> I don't think so, actually, I was mostly worried you are passing
> address from get_page() into kfree() here ;) But patch 11 cures that,
> so that's good, too.

I realized that after sending my last mail. I'll fix that in v3 even
it's just a transient bug.

Thomas.
diff mbox series

Patch

diff --git a/drivers/net/ethernet/sgi/ioc3-eth.c b/drivers/net/ethernet/sgi/ioc3-eth.c
index ba18a53fbbe6..d9d94a55ac34 100644
--- a/drivers/net/ethernet/sgi/ioc3-eth.c
+++ b/drivers/net/ethernet/sgi/ioc3-eth.c
@@ -803,25 +803,17 @@  static void ioc3_free_rings(struct ioc3_private *ip)
 	struct sk_buff *skb;
 	int rx_entry, n_entry;
 
-	if (ip->txr) {
-		ioc3_clean_tx_ring(ip);
-		free_pages((unsigned long)ip->txr, 2);
-		ip->txr = NULL;
-	}
+	ioc3_clean_tx_ring(ip);
 
-	if (ip->rxr) {
-		n_entry = ip->rx_ci;
-		rx_entry = ip->rx_pi;
+	n_entry = ip->rx_ci;
+	rx_entry = ip->rx_pi;
 
-		while (n_entry != rx_entry) {
-			skb = ip->rx_skbs[n_entry];
-			if (skb)
-				dev_kfree_skb_any(skb);
+	while (n_entry != rx_entry) {
+		skb = ip->rx_skbs[n_entry];
+		if (skb)
+			dev_kfree_skb_any(skb);
 
-			n_entry = (n_entry + 1) & RX_RING_MASK;
-		}
-		free_page((unsigned long)ip->rxr);
-		ip->rxr = NULL;
+		n_entry = (n_entry + 1) & RX_RING_MASK;
 	}
 }
 
@@ -829,49 +821,34 @@  static void ioc3_alloc_rings(struct net_device *dev)
 {
 	struct ioc3_private *ip = netdev_priv(dev);
 	struct ioc3_erxbuf *rxb;
-	unsigned long *rxr;
 	int i;
 
-	if (!ip->rxr) {
-		/* Allocate and initialize rx ring.  4kb = 512 entries  */
-		ip->rxr = (unsigned long *)get_zeroed_page(GFP_ATOMIC);
-		rxr = ip->rxr;
-		if (!rxr)
-			pr_err("%s: get_zeroed_page() failed!\n", __func__);
-
-		/* Now the rx buffers.  The RX ring may be larger but
-		 * we only allocate 16 buffers for now.  Need to tune
-		 * this for performance and memory later.
-		 */
-		for (i = 0; i < RX_BUFFS; i++) {
-			struct sk_buff *skb;
+	/* Now the rx buffers.  The RX ring may be larger but
+	 * we only allocate 16 buffers for now.  Need to tune
+	 * this for performance and memory later.
+	 */
+	for (i = 0; i < RX_BUFFS; i++) {
+		struct sk_buff *skb;
 
-			skb = ioc3_alloc_skb(RX_BUF_ALLOC_SIZE, GFP_ATOMIC);
-			if (!skb) {
-				show_free_areas(0, NULL);
-				continue;
-			}
+		skb = ioc3_alloc_skb(RX_BUF_ALLOC_SIZE, GFP_ATOMIC);
+		if (!skb) {
+			show_free_areas(0, NULL);
+			continue;
+		}
 
-			ip->rx_skbs[i] = skb;
+		ip->rx_skbs[i] = skb;
 
-			/* Because we reserve afterwards. */
-			skb_put(skb, (1664 + RX_OFFSET));
-			rxb = (struct ioc3_erxbuf *)skb->data;
-			rxr[i] = cpu_to_be64(ioc3_map(rxb, 1));
-			skb_reserve(skb, RX_OFFSET);
-		}
-		ip->rx_ci = 0;
-		ip->rx_pi = RX_BUFFS;
+		/* Because we reserve afterwards. */
+		skb_put(skb, (1664 + RX_OFFSET));
+		rxb = (struct ioc3_erxbuf *)skb->data;
+		ip->rxr[i] = cpu_to_be64(ioc3_map(rxb, 1));
+		skb_reserve(skb, RX_OFFSET);
 	}
+	ip->rx_ci = 0;
+	ip->rx_pi = RX_BUFFS;
 
-	if (!ip->txr) {
-		/* Allocate and initialize tx rings.  16kb = 128 bufs.  */
-		ip->txr = (struct ioc3_etxd *)__get_free_pages(GFP_KERNEL, 2);
-		if (!ip->txr)
-			pr_err("%s: __get_free_pages() failed!\n", __func__);
-		ip->tx_pi = 0;
-		ip->tx_ci = 0;
-	}
+	ip->tx_pi = 0;
+	ip->tx_ci = 0;
 }
 
 static void ioc3_init_rings(struct net_device *dev)
@@ -1239,6 +1216,23 @@  static int ioc3_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	timer_setup(&ip->ioc3_timer, ioc3_timer, 0);
 
 	ioc3_stop(ip);
+
+	/* Allocate and rx ring.  4kb = 512 entries  */
+	ip->rxr = (unsigned long *)get_zeroed_page(GFP_ATOMIC);
+	if (!ip->rxr) {
+		pr_err("ioc3-eth: rx ring allocation failed\n");
+		err = -ENOMEM;
+		goto out_stop;
+	}
+
+	/* Allocate tx rings.  16kb = 128 bufs.  */
+	ip->txr = (struct ioc3_etxd *)__get_free_pages(GFP_KERNEL, 2);
+	if (!ip->txr) {
+		pr_err("ioc3-eth: tx ring allocation failed\n");
+		err = -ENOMEM;
+		goto out_stop;
+	}
+
 	ioc3_init(dev);
 
 	ip->pdev = pdev;
@@ -1293,6 +1287,8 @@  static int ioc3_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	ioc3_stop(ip);
 	del_timer_sync(&ip->ioc3_timer);
 	ioc3_free_rings(ip);
+	kfree(ip->rxr);
+	kfree(ip->txr);
 out_res:
 	pci_release_regions(pdev);
 out_free:
@@ -1310,6 +1306,9 @@  static void ioc3_remove_one(struct pci_dev *pdev)
 	struct net_device *dev = pci_get_drvdata(pdev);
 	struct ioc3_private *ip = netdev_priv(dev);
 
+	kfree(ip->rxr);
+	kfree(ip->txr);
+
 	unregister_netdev(dev);
 	del_timer_sync(&ip->ioc3_timer);