* [PATCH net-next v2 1/3] net: add macro netif_subqueue_completed_wake
2023-04-15 7:18 [PATCH net-next v2 0/3] r8169: use new macros from netdev_queues.h Heiner Kallweit
@ 2023-04-15 7:20 ` Heiner Kallweit
2023-04-15 7:22 ` [PATCH net-next v2 2/3] r8169: use new macro netif_subqueue_maybe_stop in rtl8169_start_xmit Heiner Kallweit
2023-04-15 7:23 ` [PATCH net-next v2 3/3] r8169: use new macro netif_subqueue_completed_wake in the tx cleanup path Heiner Kallweit
2 siblings, 0 replies; 7+ messages in thread
From: Heiner Kallweit @ 2023-04-15 7:20 UTC (permalink / raw)
To: Jakub Kicinski, David Miller, Paolo Abeni, Eric Dumazet,
Realtek linux nic maintainers
Cc: netdev
Add netif_subqueue_completed_wake, complementing the subqueue versions
netif_subqueue_try_stop and netif_subqueue_maybe_stop.
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
include/net/netdev_queues.h | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/include/net/netdev_queues.h b/include/net/netdev_queues.h
index b26fdb441..d68b0a483 100644
--- a/include/net/netdev_queues.h
+++ b/include/net/netdev_queues.h
@@ -160,4 +160,14 @@ netdev_txq_completed_mb(struct netdev_queue *dev_queue,
netif_txq_maybe_stop(txq, get_desc, stop_thrs, start_thrs); \
})
+#define netif_subqueue_completed_wake(dev, idx, pkts, bytes, \
+ get_desc, start_thrs) \
+ ({ \
+ struct netdev_queue *txq; \
+ \
+ txq = netdev_get_tx_queue(dev, idx); \
+ netif_txq_completed_wake(txq, pkts, bytes, \
+ get_desc, start_thrs); \
+ })
+
#endif
--
2.40.0
^ permalink raw reply related [flat|nested] 7+ messages in thread
* [PATCH net-next v2 2/3] r8169: use new macro netif_subqueue_maybe_stop in rtl8169_start_xmit
2023-04-15 7:18 [PATCH net-next v2 0/3] r8169: use new macros from netdev_queues.h Heiner Kallweit
2023-04-15 7:20 ` [PATCH net-next v2 1/3] net: add macro netif_subqueue_completed_wake Heiner Kallweit
@ 2023-04-15 7:22 ` Heiner Kallweit
2023-04-16 10:20 ` Leon Romanovsky
2023-04-15 7:23 ` [PATCH net-next v2 3/3] r8169: use new macro netif_subqueue_completed_wake in the tx cleanup path Heiner Kallweit
2 siblings, 1 reply; 7+ messages in thread
From: Heiner Kallweit @ 2023-04-15 7:22 UTC (permalink / raw)
To: Jakub Kicinski, David Miller, Paolo Abeni, Eric Dumazet,
Realtek linux nic maintainers
Cc: netdev
Use new net core macro netif_subqueue_maybe_stop in the start_xmit path
to simplify the code. Whilst at it, set the tx queue start threshold to
twice the stop threshold. Before values were the same, resulting in
stopping/starting the queue more often than needed.
v2:
- ring doorbell if queue was stopped
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
drivers/net/ethernet/realtek/r8169_main.c | 39 +++++++----------------
1 file changed, 11 insertions(+), 28 deletions(-)
diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index 9f8357bbc..fff44d46b 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -30,6 +30,7 @@
#include <linux/ipv6.h>
#include <asm/unaligned.h>
#include <net/ip6_checksum.h>
+#include <net/netdev_queues.h>
#include "r8169.h"
#include "r8169_firmware.h"
@@ -68,6 +69,8 @@
#define NUM_RX_DESC 256 /* Number of Rx descriptor registers */
#define R8169_TX_RING_BYTES (NUM_TX_DESC * sizeof(struct TxDesc))
#define R8169_RX_RING_BYTES (NUM_RX_DESC * sizeof(struct RxDesc))
+#define R8169_TX_STOP_THRS (MAX_SKB_FRAGS + 1)
+#define R8169_TX_START_THRS (2 * R8169_TX_STOP_THRS)
#define OCP_STD_PHY_BASE 0xa400
@@ -4162,13 +4165,9 @@ static bool rtl8169_tso_csum_v2(struct rtl8169_private *tp,
return true;
}
-static bool rtl_tx_slots_avail(struct rtl8169_private *tp)
+static unsigned int rtl_tx_slots_avail(struct rtl8169_private *tp)
{
- unsigned int slots_avail = READ_ONCE(tp->dirty_tx) + NUM_TX_DESC
- - READ_ONCE(tp->cur_tx);
-
- /* A skbuff with nr_frags needs nr_frags+1 entries in the tx queue */
- return slots_avail > MAX_SKB_FRAGS;
+ return READ_ONCE(tp->dirty_tx) + NUM_TX_DESC - READ_ONCE(tp->cur_tx);
}
/* Versions RTL8102e and from RTL8168c onwards support csum_v2 */
@@ -4245,27 +4244,10 @@ static netdev_tx_t rtl8169_start_xmit(struct sk_buff *skb,
WRITE_ONCE(tp->cur_tx, tp->cur_tx + frags + 1);
- stop_queue = !rtl_tx_slots_avail(tp);
- if (unlikely(stop_queue)) {
- /* Avoid wrongly optimistic queue wake-up: rtl_tx thread must
- * not miss a ring update when it notices a stopped queue.
- */
- smp_wmb();
- netif_stop_queue(dev);
- /* Sync with rtl_tx:
- * - publish queue status and cur_tx ring index (write barrier)
- * - refresh dirty_tx ring index (read barrier).
- * May the current thread have a pessimistic view of the ring
- * status and forget to wake up queue, a racing rtl_tx thread
- * can't.
- */
- smp_mb__after_atomic();
- if (rtl_tx_slots_avail(tp))
- netif_start_queue(dev);
- door_bell = true;
- }
-
- if (door_bell)
+ stop_queue = !netif_subqueue_maybe_stop(dev, 0, rtl_tx_slots_avail(tp),
+ R8169_TX_STOP_THRS,
+ R8169_TX_START_THRS);
+ if (door_bell || stop_queue)
rtl8169_doorbell(tp);
return NETDEV_TX_OK;
@@ -4400,7 +4382,8 @@ static void rtl_tx(struct net_device *dev, struct rtl8169_private *tp,
* ring status.
*/
smp_store_mb(tp->dirty_tx, dirty_tx);
- if (netif_queue_stopped(dev) && rtl_tx_slots_avail(tp))
+ if (netif_queue_stopped(dev) &&
+ rtl_tx_slots_avail(tp) >= R8169_TX_START_THRS)
netif_wake_queue(dev);
/*
* 8168 hack: TxPoll requests are lost when the Tx packets are
--
2.40.0
^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH net-next v2 2/3] r8169: use new macro netif_subqueue_maybe_stop in rtl8169_start_xmit
2023-04-15 7:22 ` [PATCH net-next v2 2/3] r8169: use new macro netif_subqueue_maybe_stop in rtl8169_start_xmit Heiner Kallweit
@ 2023-04-16 10:20 ` Leon Romanovsky
2023-04-16 11:33 ` Heiner Kallweit
0 siblings, 1 reply; 7+ messages in thread
From: Leon Romanovsky @ 2023-04-16 10:20 UTC (permalink / raw)
To: Heiner Kallweit
Cc: Jakub Kicinski, David Miller, Paolo Abeni, Eric Dumazet,
Realtek linux nic maintainers, netdev
On Sat, Apr 15, 2023 at 09:22:11AM +0200, Heiner Kallweit wrote:
> Use new net core macro netif_subqueue_maybe_stop in the start_xmit path
> to simplify the code. Whilst at it, set the tx queue start threshold to
> twice the stop threshold. Before values were the same, resulting in
> stopping/starting the queue more often than needed.
>
> v2:
> - ring doorbell if queue was stopped
Please put changelog under "---" markup, below tags section.
Thanks
>
> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
> ---
> drivers/net/ethernet/realtek/r8169_main.c | 39 +++++++----------------
> 1 file changed, 11 insertions(+), 28 deletions(-)
>
> diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
> index 9f8357bbc..fff44d46b 100644
> --- a/drivers/net/ethernet/realtek/r8169_main.c
> +++ b/drivers/net/ethernet/realtek/r8169_main.c
> @@ -30,6 +30,7 @@
> #include <linux/ipv6.h>
> #include <asm/unaligned.h>
> #include <net/ip6_checksum.h>
> +#include <net/netdev_queues.h>
>
> #include "r8169.h"
> #include "r8169_firmware.h"
> @@ -68,6 +69,8 @@
> #define NUM_RX_DESC 256 /* Number of Rx descriptor registers */
> #define R8169_TX_RING_BYTES (NUM_TX_DESC * sizeof(struct TxDesc))
> #define R8169_RX_RING_BYTES (NUM_RX_DESC * sizeof(struct RxDesc))
> +#define R8169_TX_STOP_THRS (MAX_SKB_FRAGS + 1)
> +#define R8169_TX_START_THRS (2 * R8169_TX_STOP_THRS)
>
> #define OCP_STD_PHY_BASE 0xa400
>
> @@ -4162,13 +4165,9 @@ static bool rtl8169_tso_csum_v2(struct rtl8169_private *tp,
> return true;
> }
>
> -static bool rtl_tx_slots_avail(struct rtl8169_private *tp)
> +static unsigned int rtl_tx_slots_avail(struct rtl8169_private *tp)
> {
> - unsigned int slots_avail = READ_ONCE(tp->dirty_tx) + NUM_TX_DESC
> - - READ_ONCE(tp->cur_tx);
> -
> - /* A skbuff with nr_frags needs nr_frags+1 entries in the tx queue */
> - return slots_avail > MAX_SKB_FRAGS;
> + return READ_ONCE(tp->dirty_tx) + NUM_TX_DESC - READ_ONCE(tp->cur_tx);
> }
>
> /* Versions RTL8102e and from RTL8168c onwards support csum_v2 */
> @@ -4245,27 +4244,10 @@ static netdev_tx_t rtl8169_start_xmit(struct sk_buff *skb,
>
> WRITE_ONCE(tp->cur_tx, tp->cur_tx + frags + 1);
>
> - stop_queue = !rtl_tx_slots_avail(tp);
> - if (unlikely(stop_queue)) {
> - /* Avoid wrongly optimistic queue wake-up: rtl_tx thread must
> - * not miss a ring update when it notices a stopped queue.
> - */
> - smp_wmb();
> - netif_stop_queue(dev);
> - /* Sync with rtl_tx:
> - * - publish queue status and cur_tx ring index (write barrier)
> - * - refresh dirty_tx ring index (read barrier).
> - * May the current thread have a pessimistic view of the ring
> - * status and forget to wake up queue, a racing rtl_tx thread
> - * can't.
> - */
> - smp_mb__after_atomic();
> - if (rtl_tx_slots_avail(tp))
> - netif_start_queue(dev);
> - door_bell = true;
> - }
> -
> - if (door_bell)
> + stop_queue = !netif_subqueue_maybe_stop(dev, 0, rtl_tx_slots_avail(tp),
> + R8169_TX_STOP_THRS,
> + R8169_TX_START_THRS);
> + if (door_bell || stop_queue)
> rtl8169_doorbell(tp);
>
> return NETDEV_TX_OK;
> @@ -4400,7 +4382,8 @@ static void rtl_tx(struct net_device *dev, struct rtl8169_private *tp,
> * ring status.
> */
> smp_store_mb(tp->dirty_tx, dirty_tx);
> - if (netif_queue_stopped(dev) && rtl_tx_slots_avail(tp))
> + if (netif_queue_stopped(dev) &&
> + rtl_tx_slots_avail(tp) >= R8169_TX_START_THRS)
> netif_wake_queue(dev);
> /*
> * 8168 hack: TxPoll requests are lost when the Tx packets are
> --
> 2.40.0
>
>
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH net-next v2 2/3] r8169: use new macro netif_subqueue_maybe_stop in rtl8169_start_xmit
2023-04-16 10:20 ` Leon Romanovsky
@ 2023-04-16 11:33 ` Heiner Kallweit
2023-04-16 13:24 ` Leon Romanovsky
0 siblings, 1 reply; 7+ messages in thread
From: Heiner Kallweit @ 2023-04-16 11:33 UTC (permalink / raw)
To: Leon Romanovsky
Cc: Jakub Kicinski, David Miller, Paolo Abeni, Eric Dumazet,
Realtek linux nic maintainers, netdev
On 16.04.2023 12:20, Leon Romanovsky wrote:
> On Sat, Apr 15, 2023 at 09:22:11AM +0200, Heiner Kallweit wrote:
>> Use new net core macro netif_subqueue_maybe_stop in the start_xmit path
>> to simplify the code. Whilst at it, set the tx queue start threshold to
>> twice the stop threshold. Before values were the same, resulting in
>> stopping/starting the queue more often than needed.
>>
>> v2:
>> - ring doorbell if queue was stopped
>
> Please put changelog under "---" markup, below tags section.
>
I know that this would be the standard. IIRC Dave once requested to
make the change log part of the commit message.
> Thanks
>
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH net-next v2 2/3] r8169: use new macro netif_subqueue_maybe_stop in rtl8169_start_xmit
2023-04-16 11:33 ` Heiner Kallweit
@ 2023-04-16 13:24 ` Leon Romanovsky
0 siblings, 0 replies; 7+ messages in thread
From: Leon Romanovsky @ 2023-04-16 13:24 UTC (permalink / raw)
To: Heiner Kallweit
Cc: Jakub Kicinski, David Miller, Paolo Abeni, Eric Dumazet,
Realtek linux nic maintainers, netdev
On Sun, Apr 16, 2023 at 01:33:11PM +0200, Heiner Kallweit wrote:
> On 16.04.2023 12:20, Leon Romanovsky wrote:
> > On Sat, Apr 15, 2023 at 09:22:11AM +0200, Heiner Kallweit wrote:
> >> Use new net core macro netif_subqueue_maybe_stop in the start_xmit path
> >> to simplify the code. Whilst at it, set the tx queue start threshold to
> >> twice the stop threshold. Before values were the same, resulting in
> >> stopping/starting the queue more often than needed.
> >>
> >> v2:
> >> - ring doorbell if queue was stopped
> >
> > Please put changelog under "---" markup, below tags section.
> >
> I know that this would be the standard. IIRC Dave once requested to
> make the change log part of the commit message.
I can imagine how it was useful before lore.kernel.org appeared.
Thanks
>
> > Thanks
> >
>
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH net-next v2 3/3] r8169: use new macro netif_subqueue_completed_wake in the tx cleanup path
2023-04-15 7:18 [PATCH net-next v2 0/3] r8169: use new macros from netdev_queues.h Heiner Kallweit
2023-04-15 7:20 ` [PATCH net-next v2 1/3] net: add macro netif_subqueue_completed_wake Heiner Kallweit
2023-04-15 7:22 ` [PATCH net-next v2 2/3] r8169: use new macro netif_subqueue_maybe_stop in rtl8169_start_xmit Heiner Kallweit
@ 2023-04-15 7:23 ` Heiner Kallweit
2 siblings, 0 replies; 7+ messages in thread
From: Heiner Kallweit @ 2023-04-15 7:23 UTC (permalink / raw)
To: Jakub Kicinski, David Miller, Paolo Abeni, Eric Dumazet,
Realtek linux nic maintainers
Cc: netdev
Use new net core macro netif_subqueue_completed_wake to simplify
the code of the tx cleanup path.
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
drivers/net/ethernet/realtek/r8169_main.c | 16 ++++------------
1 file changed, 4 insertions(+), 12 deletions(-)
diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index fff44d46b..a7e376e7e 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -4371,20 +4371,12 @@ static void rtl_tx(struct net_device *dev, struct rtl8169_private *tp,
}
if (tp->dirty_tx != dirty_tx) {
- netdev_completed_queue(dev, pkts_compl, bytes_compl);
dev_sw_netstats_tx_add(dev, pkts_compl, bytes_compl);
+ WRITE_ONCE(tp->dirty_tx, dirty_tx);
- /* Sync with rtl8169_start_xmit:
- * - publish dirty_tx ring index (write barrier)
- * - refresh cur_tx ring index and queue status (read barrier)
- * May the current thread miss the stopped queue condition,
- * a racing xmit thread can only have a right view of the
- * ring status.
- */
- smp_store_mb(tp->dirty_tx, dirty_tx);
- if (netif_queue_stopped(dev) &&
- rtl_tx_slots_avail(tp) >= R8169_TX_START_THRS)
- netif_wake_queue(dev);
+ netif_subqueue_completed_wake(dev, 0, pkts_compl, bytes_compl,
+ rtl_tx_slots_avail(tp),
+ R8169_TX_START_THRS);
/*
* 8168 hack: TxPoll requests are lost when the Tx packets are
* too close. Let's kick an extra TxPoll request when a burst
--
2.40.0
^ permalink raw reply related [flat|nested] 7+ messages in thread