* [PATCH net-next 0/9] intel: switch to napi_build_skb()
@ 2021-11-23 17:18 Alexander Lobakin
2021-11-23 17:18 ` [PATCH net-next 1/9] e1000: switch to napi_consume_skb() Alexander Lobakin
` (8 more replies)
0 siblings, 9 replies; 19+ messages in thread
From: Alexander Lobakin @ 2021-11-23 17:18 UTC (permalink / raw)
To: intel-wired-lan
Cc: Alexander Lobakin, Tony Nguyen, Jesse Brandeburg,
Maciej Fijalkowski, Michal Swiatkowski, David S. Miller,
Jakub Kicinski, netdev, linux-kernel
napi_build_skb() I introduced earlier this year ([0]) aims
to decrease MM pressure and the overhead from in-place
kmem_cache_alloc() on each Rx entry processing by decaching
skbuff_heads from NAPI per-cpu cache filled prior to that by
napi_consume_skb() (so it is sort of a direct shortcut for
free -> mm -> alloc cycle).
Currently, no in-tree drivers use it. Switch all Intel Ethernet
drivers to it to get slight-to-medium perf boosts depending on
the frame size.
ice driver, 50 Gbps link, pktgen + XDP_PASS (local in) sample:
frame_size/nthreads 64/42 128/20 256/8 512/4 1024/2 1532/1
net-next (Kpps) 46062 34654 18248 9830 5343 2714
series 47438 34708 18330 9875 5435 2777
increase 2.9% 0.15% 0.45% 0.46% 1.72% 2.32%
Additionally, e1000's been switched to napi_consume_skb() as it's
safe and works fine there, and there's no point in napi_build_skb()
without paired NAPI cache feeding point.
[0] https://lore.kernel.org/all/20210213141021.87840-1-alobakin@pm.me
Alexander Lobakin (9):
e1000: switch to napi_consume_skb()
e1000: switch to napi_build_skb()
i40e: switch to napi_build_skb()
iavf: switch to napi_build_skb()
ice: switch to napi_build_skb()
igb: switch to napi_build_skb()
igc: switch to napi_build_skb()
ixgbe: switch to napi_build_skb()
ixgbevf: switch to napi_build_skb()
drivers/net/ethernet/intel/e1000/e1000_main.c | 14 ++++++++------
drivers/net/ethernet/intel/i40e/i40e_txrx.c | 2 +-
drivers/net/ethernet/intel/iavf/iavf_txrx.c | 2 +-
drivers/net/ethernet/intel/ice/ice_txrx.c | 2 +-
drivers/net/ethernet/intel/igb/igb_main.c | 2 +-
drivers/net/ethernet/intel/igc/igc_main.c | 2 +-
drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 2 +-
drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c | 2 +-
8 files changed, 15 insertions(+), 13 deletions(-)
--
2.33.1
^ permalink raw reply [flat|nested] 19+ messages in thread
* [PATCH net-next 1/9] e1000: switch to napi_consume_skb()
2021-11-23 17:18 [PATCH net-next 0/9] intel: switch to napi_build_skb() Alexander Lobakin
@ 2021-11-23 17:18 ` Alexander Lobakin
2021-12-28 0:06 ` [Intel-wired-lan] " Brelinski, Tony
2021-11-23 17:18 ` [PATCH net-next 2/9] e1000: switch to napi_build_skb() Alexander Lobakin
` (7 subsequent siblings)
8 siblings, 1 reply; 19+ messages in thread
From: Alexander Lobakin @ 2021-11-23 17:18 UTC (permalink / raw)
To: intel-wired-lan
Cc: Alexander Lobakin, Tony Nguyen, Jesse Brandeburg,
Maciej Fijalkowski, Michal Swiatkowski, David S. Miller,
Jakub Kicinski, netdev, linux-kernel
In order to take the best from per-cpu NAPI skbuff_head caches and
CPU cycles, let's switch from dev_kfree_skb_any(), which passes skb
back to the mm layer, to napi_consume_skb(), which feeds those
caches on non-zero budget instead (falls back to the former on 0).
Do the replacement in e1000_unmap_and_free_tx_resource(). There are
4 call sites of this function throughout the driver:
* e1000_clean_tx_ring(). Slowpath, process context, cleans the
whole Tx ring on ifdown. Use budget of 0 here;
* e1000_tx_map(). Hotpath, net Tx softirq, unmaps the buffers in
case of error. Use 0 as well;
* e1000_clean_tx_irq(). Hotpath, NAPI Tx completion polling cycle.
As the driver doesn't count completed Tx entries towards the NAPI
budget, just use the poll budget of 64 to utilize caches.
Apart from being a preparation for switching to napi_build_skb(),
this is useful on its own as well, as napi_consume_skb() flushes
skb caches by batches of 32 instead of one-at-a-time.
Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
---
drivers/net/ethernet/intel/e1000/e1000_main.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/drivers/net/ethernet/intel/e1000/e1000_main.c b/drivers/net/ethernet/intel/e1000/e1000_main.c
index 669060a2e6aa..975a145d48ef 100644
--- a/drivers/net/ethernet/intel/e1000/e1000_main.c
+++ b/drivers/net/ethernet/intel/e1000/e1000_main.c
@@ -1953,7 +1953,8 @@ void e1000_free_all_tx_resources(struct e1000_adapter *adapter)
static void
e1000_unmap_and_free_tx_resource(struct e1000_adapter *adapter,
- struct e1000_tx_buffer *buffer_info)
+ struct e1000_tx_buffer *buffer_info,
+ int budget)
{
if (buffer_info->dma) {
if (buffer_info->mapped_as_page)
@@ -1966,7 +1967,7 @@ e1000_unmap_and_free_tx_resource(struct e1000_adapter *adapter,
buffer_info->dma = 0;
}
if (buffer_info->skb) {
- dev_kfree_skb_any(buffer_info->skb);
+ napi_consume_skb(buffer_info->skb, budget);
buffer_info->skb = NULL;
}
buffer_info->time_stamp = 0;
@@ -1990,7 +1991,7 @@ static void e1000_clean_tx_ring(struct e1000_adapter *adapter,
for (i = 0; i < tx_ring->count; i++) {
buffer_info = &tx_ring->buffer_info[i];
- e1000_unmap_and_free_tx_resource(adapter, buffer_info);
+ e1000_unmap_and_free_tx_resource(adapter, buffer_info, 0);
}
netdev_reset_queue(adapter->netdev);
@@ -2958,7 +2959,7 @@ static int e1000_tx_map(struct e1000_adapter *adapter,
i += tx_ring->count;
i--;
buffer_info = &tx_ring->buffer_info[i];
- e1000_unmap_and_free_tx_resource(adapter, buffer_info);
+ e1000_unmap_and_free_tx_resource(adapter, buffer_info, 0);
}
return 0;
@@ -3856,7 +3857,8 @@ static bool e1000_clean_tx_irq(struct e1000_adapter *adapter,
}
}
- e1000_unmap_and_free_tx_resource(adapter, buffer_info);
+ e1000_unmap_and_free_tx_resource(adapter, buffer_info,
+ 64);
tx_desc->upper.data = 0;
if (unlikely(++i == tx_ring->count))
--
2.33.1
^ permalink raw reply related [flat|nested] 19+ messages in thread
* [PATCH net-next 2/9] e1000: switch to napi_build_skb()
2021-11-23 17:18 [PATCH net-next 0/9] intel: switch to napi_build_skb() Alexander Lobakin
2021-11-23 17:18 ` [PATCH net-next 1/9] e1000: switch to napi_consume_skb() Alexander Lobakin
@ 2021-11-23 17:18 ` Alexander Lobakin
2021-12-28 0:07 ` [Intel-wired-lan] " Brelinski, Tony
2021-11-23 17:18 ` [PATCH net-next 3/9] i40e: " Alexander Lobakin
` (6 subsequent siblings)
8 siblings, 1 reply; 19+ messages in thread
From: Alexander Lobakin @ 2021-11-23 17:18 UTC (permalink / raw)
To: intel-wired-lan
Cc: Alexander Lobakin, Tony Nguyen, Jesse Brandeburg,
Maciej Fijalkowski, Michal Swiatkowski, David S. Miller,
Jakub Kicinski, netdev, linux-kernel
napi_build_skb() reuses per-cpu NAPI skbuff_head cache in order
to save some cycles on freeing/allocating skbuff_heads on every
new Rx or completed Tx element.
e1000 driver runs Tx completion polling cycle right before the Rx
one. Now that e1000 uses napi_consume_skb() to put skbuff_heads of
completed entries into the cache, it will never empty and always
warm at that moment. Switch to the napi_build_skb() to relax mm
pressure on heavy Rx and increase throughput.
Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
---
drivers/net/ethernet/intel/e1000/e1000_main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/intel/e1000/e1000_main.c b/drivers/net/ethernet/intel/e1000/e1000_main.c
index 975a145d48ef..3f5feb55cfba 100644
--- a/drivers/net/ethernet/intel/e1000/e1000_main.c
+++ b/drivers/net/ethernet/intel/e1000/e1000_main.c
@@ -4384,7 +4384,7 @@ static bool e1000_clean_rx_irq(struct e1000_adapter *adapter,
if (!skb) {
unsigned int frag_len = e1000_frag_len(adapter);
- skb = build_skb(data - E1000_HEADROOM, frag_len);
+ skb = napi_build_skb(data - E1000_HEADROOM, frag_len);
if (!skb) {
adapter->alloc_rx_buff_failed++;
break;
--
2.33.1
^ permalink raw reply related [flat|nested] 19+ messages in thread
* [PATCH net-next 3/9] i40e: switch to napi_build_skb()
2021-11-23 17:18 [PATCH net-next 0/9] intel: switch to napi_build_skb() Alexander Lobakin
2021-11-23 17:18 ` [PATCH net-next 1/9] e1000: switch to napi_consume_skb() Alexander Lobakin
2021-11-23 17:18 ` [PATCH net-next 2/9] e1000: switch to napi_build_skb() Alexander Lobakin
@ 2021-11-23 17:18 ` Alexander Lobakin
2021-12-03 14:44 ` [Intel-wired-lan] " G, GurucharanX
2021-11-23 17:18 ` [PATCH net-next 4/9] iavf: " Alexander Lobakin
` (5 subsequent siblings)
8 siblings, 1 reply; 19+ messages in thread
From: Alexander Lobakin @ 2021-11-23 17:18 UTC (permalink / raw)
To: intel-wired-lan
Cc: Alexander Lobakin, Tony Nguyen, Jesse Brandeburg,
Maciej Fijalkowski, Michal Swiatkowski, David S. Miller,
Jakub Kicinski, netdev, linux-kernel
napi_build_skb() reuses per-cpu NAPI skbuff_head cache in order
to save some cycles on freeing/allocating skbuff_heads on every
new Rx or completed Tx.
i40e driver runs Tx completion polling cycle right before the Rx
one and uses napi_consume_skb() to feed the cache with skbuff_heads
of completed entries, so it's never empty and always warm at that
moment. Switch to the napi_build_skb() to relax mm pressure on
heavy Rx.
Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
---
drivers/net/ethernet/intel/i40e/i40e_txrx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index 10a83e5385c7..9e3991caa5c9 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -2204,7 +2204,7 @@ static struct sk_buff *i40e_build_skb(struct i40e_ring *rx_ring,
net_prefetch(xdp->data_meta);
/* build an skb around the page buffer */
- skb = build_skb(xdp->data_hard_start, truesize);
+ skb = napi_build_skb(xdp->data_hard_start, truesize);
if (unlikely(!skb))
return NULL;
--
2.33.1
^ permalink raw reply related [flat|nested] 19+ messages in thread
* [PATCH net-next 4/9] iavf: switch to napi_build_skb()
2021-11-23 17:18 [PATCH net-next 0/9] intel: switch to napi_build_skb() Alexander Lobakin
` (2 preceding siblings ...)
2021-11-23 17:18 ` [PATCH net-next 3/9] i40e: " Alexander Lobakin
@ 2021-11-23 17:18 ` Alexander Lobakin
2021-12-14 12:50 ` [Intel-wired-lan] " Jankowski, Konrad0
2021-11-23 17:18 ` [PATCH net-next 5/9] ice: " Alexander Lobakin
` (4 subsequent siblings)
8 siblings, 1 reply; 19+ messages in thread
From: Alexander Lobakin @ 2021-11-23 17:18 UTC (permalink / raw)
To: intel-wired-lan
Cc: Alexander Lobakin, Tony Nguyen, Jesse Brandeburg,
Maciej Fijalkowski, Michal Swiatkowski, David S. Miller,
Jakub Kicinski, netdev, linux-kernel
napi_build_skb() reuses per-cpu NAPI skbuff_head cache in order
to save some cycles on freeing/allocating skbuff_heads on every
new Rx or completed Tx.
iavf driver runs Tx completion polling cycle right before the Rx
one and uses napi_consume_skb() to feed the cache with skbuff_heads
of completed entries, so it's never empty and always warm at that
moment. Switch to the napi_build_skb() to relax mm pressure on
heavy Rx.
Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
---
drivers/net/ethernet/intel/iavf/iavf_txrx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/intel/iavf/iavf_txrx.c b/drivers/net/ethernet/intel/iavf/iavf_txrx.c
index 3525eab8e9f9..90fdd828e5d8 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_txrx.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_txrx.c
@@ -1363,7 +1363,7 @@ static struct sk_buff *iavf_build_skb(struct iavf_ring *rx_ring,
net_prefetch(va);
/* build an skb around the page buffer */
- skb = build_skb(va - IAVF_SKB_PAD, truesize);
+ skb = napi_build_skb(va - IAVF_SKB_PAD, truesize);
if (unlikely(!skb))
return NULL;
--
2.33.1
^ permalink raw reply related [flat|nested] 19+ messages in thread
* [PATCH net-next 5/9] ice: switch to napi_build_skb()
2021-11-23 17:18 [PATCH net-next 0/9] intel: switch to napi_build_skb() Alexander Lobakin
` (3 preceding siblings ...)
2021-11-23 17:18 ` [PATCH net-next 4/9] iavf: " Alexander Lobakin
@ 2021-11-23 17:18 ` Alexander Lobakin
2021-12-07 10:03 ` [Intel-wired-lan] " G, GurucharanX
2021-11-23 17:18 ` [PATCH net-next 6/9] igb: " Alexander Lobakin
` (3 subsequent siblings)
8 siblings, 1 reply; 19+ messages in thread
From: Alexander Lobakin @ 2021-11-23 17:18 UTC (permalink / raw)
To: intel-wired-lan
Cc: Alexander Lobakin, Tony Nguyen, Jesse Brandeburg,
Maciej Fijalkowski, Michal Swiatkowski, David S. Miller,
Jakub Kicinski, netdev, linux-kernel
napi_build_skb() reuses per-cpu NAPI skbuff_head cache in order
to save some cycles on freeing/allocating skbuff_heads on every
new Rx or completed Tx.
ice driver runs Tx completion polling cycle right before the Rx
one and uses napi_consume_skb() to feed the cache with skbuff_heads
of completed entries, so it's never empty and always warm at that
moment. Switch to the napi_build_skb() to relax mm pressure on
heavy Rx.
Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
---
drivers/net/ethernet/intel/ice/ice_txrx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/intel/ice/ice_txrx.c b/drivers/net/ethernet/intel/ice/ice_txrx.c
index bc3ba19dc88f..b7be441efe54 100644
--- a/drivers/net/ethernet/intel/ice/ice_txrx.c
+++ b/drivers/net/ethernet/intel/ice/ice_txrx.c
@@ -933,7 +933,7 @@ ice_build_skb(struct ice_rx_ring *rx_ring, struct ice_rx_buf *rx_buf,
*/
net_prefetch(xdp->data_meta);
/* build an skb around the page buffer */
- skb = build_skb(xdp->data_hard_start, truesize);
+ skb = napi_build_skb(xdp->data_hard_start, truesize);
if (unlikely(!skb))
return NULL;
--
2.33.1
^ permalink raw reply related [flat|nested] 19+ messages in thread
* [PATCH net-next 6/9] igb: switch to napi_build_skb()
2021-11-23 17:18 [PATCH net-next 0/9] intel: switch to napi_build_skb() Alexander Lobakin
` (4 preceding siblings ...)
2021-11-23 17:18 ` [PATCH net-next 5/9] ice: " Alexander Lobakin
@ 2021-11-23 17:18 ` Alexander Lobakin
2021-12-22 3:45 ` [Intel-wired-lan] " G, GurucharanX
2021-11-23 17:18 ` [PATCH net-next 7/9] igc: " Alexander Lobakin
` (2 subsequent siblings)
8 siblings, 1 reply; 19+ messages in thread
From: Alexander Lobakin @ 2021-11-23 17:18 UTC (permalink / raw)
To: intel-wired-lan
Cc: Alexander Lobakin, Tony Nguyen, Jesse Brandeburg,
Maciej Fijalkowski, Michal Swiatkowski, David S. Miller,
Jakub Kicinski, netdev, linux-kernel
napi_build_skb() reuses per-cpu NAPI skbuff_head cache in order
to save some cycles on freeing/allocating skbuff_heads on every
new Rx or completed Tx.
igb driver runs Tx completion polling cycle right before the Rx
one and uses napi_consume_skb() to feed the cache with skbuff_heads
of completed entries, so it's never empty and always warm at that
moment. Switch to the napi_build_skb() to relax mm pressure on
heavy Rx.
Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
---
drivers/net/ethernet/intel/igb/igb_main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c
index 18a019a47182..c49a8d7409ed 100644
--- a/drivers/net/ethernet/intel/igb/igb_main.c
+++ b/drivers/net/ethernet/intel/igb/igb_main.c
@@ -8367,7 +8367,7 @@ static struct sk_buff *igb_build_skb(struct igb_ring *rx_ring,
net_prefetch(xdp->data_meta);
/* build an skb around the page buffer */
- skb = build_skb(xdp->data_hard_start, truesize);
+ skb = napi_build_skb(xdp->data_hard_start, truesize);
if (unlikely(!skb))
return NULL;
--
2.33.1
^ permalink raw reply related [flat|nested] 19+ messages in thread
* [PATCH net-next 7/9] igc: switch to napi_build_skb()
2021-11-23 17:18 [PATCH net-next 0/9] intel: switch to napi_build_skb() Alexander Lobakin
` (5 preceding siblings ...)
2021-11-23 17:18 ` [PATCH net-next 6/9] igb: " Alexander Lobakin
@ 2021-11-23 17:18 ` Alexander Lobakin
2021-12-08 8:15 ` [Intel-wired-lan] " Kraus, NechamaX
2021-11-23 17:18 ` [PATCH net-next 8/9] ixgbe: " Alexander Lobakin
2021-11-23 17:18 ` [PATCH net-next 9/9] ixgbevf: " Alexander Lobakin
8 siblings, 1 reply; 19+ messages in thread
From: Alexander Lobakin @ 2021-11-23 17:18 UTC (permalink / raw)
To: intel-wired-lan
Cc: Alexander Lobakin, Tony Nguyen, Jesse Brandeburg,
Maciej Fijalkowski, Michal Swiatkowski, David S. Miller,
Jakub Kicinski, netdev, linux-kernel
napi_build_skb() reuses per-cpu NAPI skbuff_head cache in order
to save some cycles on freeing/allocating skbuff_heads on every
new Rx or completed Tx.
igc driver runs Tx completion polling cycle right before the Rx
one and uses napi_consume_skb() to feed the cache with skbuff_heads
of completed entries, so it's never empty and always warm at that
moment. Switch to the napi_build_skb() to relax mm pressure on
heavy Rx.
Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
---
drivers/net/ethernet/intel/igc/igc_main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index 8e448288ee26..8b13a61ea5c9 100644
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -1729,7 +1729,7 @@ static struct sk_buff *igc_build_skb(struct igc_ring *rx_ring,
net_prefetch(va);
/* build an skb around the page buffer */
- skb = build_skb(va - IGC_SKB_PAD, truesize);
+ skb = napi_build_skb(va - IGC_SKB_PAD, truesize);
if (unlikely(!skb))
return NULL;
--
2.33.1
^ permalink raw reply related [flat|nested] 19+ messages in thread
* [PATCH net-next 8/9] ixgbe: switch to napi_build_skb()
2021-11-23 17:18 [PATCH net-next 0/9] intel: switch to napi_build_skb() Alexander Lobakin
` (6 preceding siblings ...)
2021-11-23 17:18 ` [PATCH net-next 7/9] igc: " Alexander Lobakin
@ 2021-11-23 17:18 ` Alexander Lobakin
2021-12-03 14:45 ` [Intel-wired-lan] " G, GurucharanX
2021-11-23 17:18 ` [PATCH net-next 9/9] ixgbevf: " Alexander Lobakin
8 siblings, 1 reply; 19+ messages in thread
From: Alexander Lobakin @ 2021-11-23 17:18 UTC (permalink / raw)
To: intel-wired-lan
Cc: Alexander Lobakin, Tony Nguyen, Jesse Brandeburg,
Maciej Fijalkowski, Michal Swiatkowski, David S. Miller,
Jakub Kicinski, netdev, linux-kernel
napi_build_skb() reuses per-cpu NAPI skbuff_head cache in order
to save some cycles on freeing/allocating skbuff_heads on every
new Rx or completed Tx.
ixgbe driver runs Tx completion polling cycle right before the Rx
one and uses napi_consume_skb() to feed the cache with skbuff_heads
of completed entries, so it's never empty and always warm at that
moment. Switch to the napi_build_skb() to relax mm pressure on
heavy Rx.
Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
---
drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 0f9f022260d7..80d2d10fd465 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -2170,7 +2170,7 @@ static struct sk_buff *ixgbe_build_skb(struct ixgbe_ring *rx_ring,
net_prefetch(xdp->data_meta);
/* build an skb to around the page buffer */
- skb = build_skb(xdp->data_hard_start, truesize);
+ skb = napi_build_skb(xdp->data_hard_start, truesize);
if (unlikely(!skb))
return NULL;
--
2.33.1
^ permalink raw reply related [flat|nested] 19+ messages in thread
* [PATCH net-next 9/9] ixgbevf: switch to napi_build_skb()
2021-11-23 17:18 [PATCH net-next 0/9] intel: switch to napi_build_skb() Alexander Lobakin
` (7 preceding siblings ...)
2021-11-23 17:18 ` [PATCH net-next 8/9] ixgbe: " Alexander Lobakin
@ 2021-11-23 17:18 ` Alexander Lobakin
2021-12-12 13:47 ` [Intel-wired-lan] " Jankowski, Konrad0
8 siblings, 1 reply; 19+ messages in thread
From: Alexander Lobakin @ 2021-11-23 17:18 UTC (permalink / raw)
To: intel-wired-lan
Cc: Alexander Lobakin, Tony Nguyen, Jesse Brandeburg,
Maciej Fijalkowski, Michal Swiatkowski, David S. Miller,
Jakub Kicinski, netdev, linux-kernel
napi_build_skb() reuses per-cpu NAPI skbuff_head cache in order
to save some cycles on freeing/allocating skbuff_heads on every
new Rx or completed Tx.
ixgbevf driver runs Tx completion polling cycle right before the Rx
one and uses napi_consume_skb() to feed the cache with skbuff_heads
of completed entries, so it's never empty and always warm at that
moment. Switch to the napi_build_skb() to relax mm pressure on
heavy Rx.
Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
---
drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
index b1dfbaff8b31..ea73fb3026bc 100644
--- a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
+++ b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
@@ -944,7 +944,7 @@ static struct sk_buff *ixgbevf_build_skb(struct ixgbevf_ring *rx_ring,
net_prefetch(xdp->data_meta);
/* build an skb around the page buffer */
- skb = build_skb(xdp->data_hard_start, truesize);
+ skb = napi_build_skb(xdp->data_hard_start, truesize);
if (unlikely(!skb))
return NULL;
--
2.33.1
^ permalink raw reply related [flat|nested] 19+ messages in thread
* RE: [Intel-wired-lan] [PATCH net-next 3/9] i40e: switch to napi_build_skb()
2021-11-23 17:18 ` [PATCH net-next 3/9] i40e: " Alexander Lobakin
@ 2021-12-03 14:44 ` G, GurucharanX
0 siblings, 0 replies; 19+ messages in thread
From: G, GurucharanX @ 2021-12-03 14:44 UTC (permalink / raw)
To: Lobakin, Alexandr, intel-wired-lan
Cc: netdev, linux-kernel, Jakub Kicinski, David S. Miller
> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf Of
> Alexander Lobakin
> Sent: Tuesday, November 23, 2021 10:49 PM
> To: intel-wired-lan@lists.osuosl.org
> Cc: netdev@vger.kernel.org; linux-kernel@vger.kernel.org; Jakub Kicinski
> <kuba@kernel.org>; David S. Miller <davem@davemloft.net>
> Subject: [Intel-wired-lan] [PATCH net-next 3/9] i40e: switch to napi_build_skb()
>
> napi_build_skb() reuses per-cpu NAPI skbuff_head cache in order to save some
> cycles on freeing/allocating skbuff_heads on every new Rx or completed Tx.
> i40e driver runs Tx completion polling cycle right before the Rx one and uses
> napi_consume_skb() to feed the cache with skbuff_heads of completed entries,
> so it's never empty and always warm at that moment. Switch to the
> napi_build_skb() to relax mm pressure on heavy Rx.
>
> Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
> Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
> ---
> drivers/net/ethernet/intel/i40e/i40e_txrx.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
Tested-by: Gurucharan G <gurucharanx.g@intel.com> (A Contingent worker at Intel)
^ permalink raw reply [flat|nested] 19+ messages in thread
* RE: [Intel-wired-lan] [PATCH net-next 8/9] ixgbe: switch to napi_build_skb()
2021-11-23 17:18 ` [PATCH net-next 8/9] ixgbe: " Alexander Lobakin
@ 2021-12-03 14:45 ` G, GurucharanX
0 siblings, 0 replies; 19+ messages in thread
From: G, GurucharanX @ 2021-12-03 14:45 UTC (permalink / raw)
To: Lobakin, Alexandr, intel-wired-lan
Cc: netdev, linux-kernel, Jakub Kicinski, David S. Miller
> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf Of
> Alexander Lobakin
> Sent: Tuesday, November 23, 2021 10:49 PM
> To: intel-wired-lan@lists.osuosl.org
> Cc: netdev@vger.kernel.org; linux-kernel@vger.kernel.org; Jakub Kicinski
> <kuba@kernel.org>; David S. Miller <davem@davemloft.net>
> Subject: [Intel-wired-lan] [PATCH net-next 8/9] ixgbe: switch to napi_build_skb()
>
> napi_build_skb() reuses per-cpu NAPI skbuff_head cache in order to save some
> cycles on freeing/allocating skbuff_heads on every new Rx or completed Tx.
> ixgbe driver runs Tx completion polling cycle right before the Rx one and uses
> napi_consume_skb() to feed the cache with skbuff_heads of completed entries,
> so it's never empty and always warm at that moment. Switch to the
> napi_build_skb() to relax mm pressure on heavy Rx.
>
> Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
> Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
> ---
> drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
Tested-by: Gurucharan G <gurucharanx.g@intel.com> (A Contingent worker at Intel)
^ permalink raw reply [flat|nested] 19+ messages in thread
* RE: [Intel-wired-lan] [PATCH net-next 5/9] ice: switch to napi_build_skb()
2021-11-23 17:18 ` [PATCH net-next 5/9] ice: " Alexander Lobakin
@ 2021-12-07 10:03 ` G, GurucharanX
0 siblings, 0 replies; 19+ messages in thread
From: G, GurucharanX @ 2021-12-07 10:03 UTC (permalink / raw)
To: Lobakin, Alexandr, intel-wired-lan
Cc: netdev, linux-kernel, Jakub Kicinski, David S. Miller
> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf Of
> Alexander Lobakin
> Sent: Tuesday, November 23, 2021 10:49 PM
> To: intel-wired-lan@lists.osuosl.org
> Cc: netdev@vger.kernel.org; linux-kernel@vger.kernel.org; Jakub Kicinski
> <kuba@kernel.org>; David S. Miller <davem@davemloft.net>
> Subject: [Intel-wired-lan] [PATCH net-next 5/9] ice: switch to napi_build_skb()
>
> napi_build_skb() reuses per-cpu NAPI skbuff_head cache in order to save some
> cycles on freeing/allocating skbuff_heads on every new Rx or completed Tx.
> ice driver runs Tx completion polling cycle right before the Rx one and uses
> napi_consume_skb() to feed the cache with skbuff_heads of completed entries,
> so it's never empty and always warm at that moment. Switch to the
> napi_build_skb() to relax mm pressure on heavy Rx.
>
> Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
> Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
> ---
> drivers/net/ethernet/intel/ice/ice_txrx.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
Tested-by: Gurucharan G <gurucharanx.g@intel.com> (A Contingent worker at Intel)
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [Intel-wired-lan] [PATCH net-next 7/9] igc: switch to napi_build_skb()
2021-11-23 17:18 ` [PATCH net-next 7/9] igc: " Alexander Lobakin
@ 2021-12-08 8:15 ` Kraus, NechamaX
0 siblings, 0 replies; 19+ messages in thread
From: Kraus, NechamaX @ 2021-12-08 8:15 UTC (permalink / raw)
To: Alexander Lobakin, intel-wired-lan
Cc: netdev, linux-kernel, Jakub Kicinski, David S. Miller
On 11/23/2021 19:18, Alexander Lobakin wrote:
> napi_build_skb() reuses per-cpu NAPI skbuff_head cache in order
> to save some cycles on freeing/allocating skbuff_heads on every
> new Rx or completed Tx.
> igc driver runs Tx completion polling cycle right before the Rx
> one and uses napi_consume_skb() to feed the cache with skbuff_heads
> of completed entries, so it's never empty and always warm at that
> moment. Switch to the napi_build_skb() to relax mm pressure on
> heavy Rx.
>
> Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
> Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
> ---
> drivers/net/ethernet/intel/igc/igc_main.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
Tested-by: Nechama Kraus <nechamax.kraus@linux.intel.com>
^ permalink raw reply [flat|nested] 19+ messages in thread
* RE: [Intel-wired-lan] [PATCH net-next 9/9] ixgbevf: switch to napi_build_skb()
2021-11-23 17:18 ` [PATCH net-next 9/9] ixgbevf: " Alexander Lobakin
@ 2021-12-12 13:47 ` Jankowski, Konrad0
0 siblings, 0 replies; 19+ messages in thread
From: Jankowski, Konrad0 @ 2021-12-12 13:47 UTC (permalink / raw)
To: Lobakin, Alexandr, intel-wired-lan
Cc: netdev, linux-kernel, Jakub Kicinski, David S. Miller
> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf Of
> Alexander Lobakin
> Sent: wtorek, 23 listopada 2021 18:19
> To: intel-wired-lan@lists.osuosl.org
> Cc: netdev@vger.kernel.org; linux-kernel@vger.kernel.org; Jakub Kicinski
> <kuba@kernel.org>; David S. Miller <davem@davemloft.net>
> Subject: [Intel-wired-lan] [PATCH net-next 9/9] ixgbevf: switch to
> napi_build_skb()
>
> napi_build_skb() reuses per-cpu NAPI skbuff_head cache in order to save
> some cycles on freeing/allocating skbuff_heads on every new Rx or
> completed Tx.
> ixgbevf driver runs Tx completion polling cycle right before the Rx one and
> uses napi_consume_skb() to feed the cache with skbuff_heads of
> completed entries, so it's never empty and always warm at that moment.
> Switch to the napi_build_skb() to relax mm pressure on heavy Rx.
>
> Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
> Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
> ---
> drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
> b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
> index b1dfbaff8b31..ea73fb3026bc 100644
> --- a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
> +++ b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
> @@ -944,7 +944,7 @@ static struct sk_buff *ixgbevf_build_skb(struct
Tested-by: Konrad Jankowski <konrad0.jankowski@intel.com>
^ permalink raw reply [flat|nested] 19+ messages in thread
* RE: [Intel-wired-lan] [PATCH net-next 4/9] iavf: switch to napi_build_skb()
2021-11-23 17:18 ` [PATCH net-next 4/9] iavf: " Alexander Lobakin
@ 2021-12-14 12:50 ` Jankowski, Konrad0
0 siblings, 0 replies; 19+ messages in thread
From: Jankowski, Konrad0 @ 2021-12-14 12:50 UTC (permalink / raw)
To: Lobakin, Alexandr, intel-wired-lan
Cc: netdev, linux-kernel, Jakub Kicinski, David S. Miller
> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf Of
> Alexander Lobakin
> Sent: wtorek, 23 listopada 2021 18:19
> To: intel-wired-lan@lists.osuosl.org
> Cc: netdev@vger.kernel.org; linux-kernel@vger.kernel.org; Jakub Kicinski
> <kuba@kernel.org>; David S. Miller <davem@davemloft.net>
> Subject: [Intel-wired-lan] [PATCH net-next 4/9] iavf: switch to
> napi_build_skb()
>
> napi_build_skb() reuses per-cpu NAPI skbuff_head cache in order to save
> some cycles on freeing/allocating skbuff_heads on every new Rx or
> completed Tx.
> iavf driver runs Tx completion polling cycle right before the Rx one and uses
> napi_consume_skb() to feed the cache with skbuff_heads of completed
> entries, so it's never empty and always warm at that moment. Switch to the
> napi_build_skb() to relax mm pressure on heavy Rx.
>
> Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
> Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
> ---
> drivers/net/ethernet/intel/iavf/iavf_txrx.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/intel/iavf/iavf_txrx.c
> b/drivers/net/ethernet/intel/iavf/iavf_txrx.c
> index 3525eab8e9f9..90fdd828e5d8 100644
> --- a/drivers/net/ethernet/intel/iavf/iavf_txrx.c
> +++ b/drivers/net/ethernet/intel/iavf/iavf_txrx.c
> @@ -1363,7 +1363,7 @@ static struct sk_buff *iavf_build_skb(struct
Tested-by: Konrad Jankowski <konrad0.jankowski@intel.com>
^ permalink raw reply [flat|nested] 19+ messages in thread
* RE: [Intel-wired-lan] [PATCH net-next 6/9] igb: switch to napi_build_skb()
2021-11-23 17:18 ` [PATCH net-next 6/9] igb: " Alexander Lobakin
@ 2021-12-22 3:45 ` G, GurucharanX
0 siblings, 0 replies; 19+ messages in thread
From: G, GurucharanX @ 2021-12-22 3:45 UTC (permalink / raw)
To: Lobakin, Alexandr, intel-wired-lan
Cc: netdev, linux-kernel, Jakub Kicinski, David S. Miller
> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf Of
> Alexander Lobakin
> Sent: Tuesday, November 23, 2021 10:49 PM
> To: intel-wired-lan@lists.osuosl.org
> Cc: netdev@vger.kernel.org; linux-kernel@vger.kernel.org; Jakub Kicinski
> <kuba@kernel.org>; David S. Miller <davem@davemloft.net>
> Subject: [Intel-wired-lan] [PATCH net-next 6/9] igb: switch to napi_build_skb()
>
> napi_build_skb() reuses per-cpu NAPI skbuff_head cache in order to save some
> cycles on freeing/allocating skbuff_heads on every new Rx or completed Tx.
> igb driver runs Tx completion polling cycle right before the Rx one and uses
> napi_consume_skb() to feed the cache with skbuff_heads of completed entries,
> so it's never empty and always warm at that moment. Switch to the
> napi_build_skb() to relax mm pressure on heavy Rx.
>
> Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
> Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
> ---
> drivers/net/ethernet/intel/igb/igb_main.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
Tested-by: Gurucharan G <gurucharanx.g@intel.com> (A Contingent worker at Intel)
^ permalink raw reply [flat|nested] 19+ messages in thread
* RE: [Intel-wired-lan] [PATCH net-next 1/9] e1000: switch to napi_consume_skb()
2021-11-23 17:18 ` [PATCH net-next 1/9] e1000: switch to napi_consume_skb() Alexander Lobakin
@ 2021-12-28 0:06 ` Brelinski, Tony
0 siblings, 0 replies; 19+ messages in thread
From: Brelinski, Tony @ 2021-12-28 0:06 UTC (permalink / raw)
To: Lobakin, Alexandr, intel-wired-lan
Cc: netdev, linux-kernel, Jakub Kicinski, David S. Miller
> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf Of
> Alexander Lobakin
> Sent: Tuesday, November 23, 2021 9:19 AM
> To: intel-wired-lan@lists.osuosl.org
> Cc: netdev@vger.kernel.org; linux-kernel@vger.kernel.org; Jakub Kicinski
> <kuba@kernel.org>; David S. Miller <davem@davemloft.net>
> Subject: [Intel-wired-lan] [PATCH net-next 1/9] e1000: switch to
> napi_consume_skb()
>
> In order to take the best from per-cpu NAPI skbuff_head caches and CPU
> cycles, let's switch from dev_kfree_skb_any(), which passes skb back to the
> mm layer, to napi_consume_skb(), which feeds those caches on non-zero
> budget instead (falls back to the former on 0).
> Do the replacement in e1000_unmap_and_free_tx_resource(). There are
> 4 call sites of this function throughout the driver:
> * e1000_clean_tx_ring(). Slowpath, process context, cleans the
> whole Tx ring on ifdown. Use budget of 0 here;
> * e1000_tx_map(). Hotpath, net Tx softirq, unmaps the buffers in
> case of error. Use 0 as well;
> * e1000_clean_tx_irq(). Hotpath, NAPI Tx completion polling cycle.
> As the driver doesn't count completed Tx entries towards the NAPI
> budget, just use the poll budget of 64 to utilize caches.
>
> Apart from being a preparation for switching to napi_build_skb(), this is
> useful on its own as well, as napi_consume_skb() flushes skb caches by
> batches of 32 instead of one-at-a-time.
>
> Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
> Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
> ---
> drivers/net/ethernet/intel/e1000/e1000_main.c | 12 +++++++-----
> 1 file changed, 7 insertions(+), 5 deletions(-)
Tested-by: Tony Brelinski <tony.brelinski@intel.com>
^ permalink raw reply [flat|nested] 19+ messages in thread
* RE: [Intel-wired-lan] [PATCH net-next 2/9] e1000: switch to napi_build_skb()
2021-11-23 17:18 ` [PATCH net-next 2/9] e1000: switch to napi_build_skb() Alexander Lobakin
@ 2021-12-28 0:07 ` Brelinski, Tony
0 siblings, 0 replies; 19+ messages in thread
From: Brelinski, Tony @ 2021-12-28 0:07 UTC (permalink / raw)
To: Lobakin, Alexandr, intel-wired-lan
Cc: netdev, linux-kernel, Jakub Kicinski, David S. Miller
> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf Of
> Alexander Lobakin
> Sent: Tuesday, November 23, 2021 9:19 AM
> To: intel-wired-lan@lists.osuosl.org
> Cc: netdev@vger.kernel.org; linux-kernel@vger.kernel.org; Jakub Kicinski
> <kuba@kernel.org>; David S. Miller <davem@davemloft.net>
> Subject: [Intel-wired-lan] [PATCH net-next 2/9] e1000: switch to
> napi_build_skb()
>
> napi_build_skb() reuses per-cpu NAPI skbuff_head cache in order to save
> some cycles on freeing/allocating skbuff_heads on every new Rx or
> completed Tx element.
> e1000 driver runs Tx completion polling cycle right before the Rx one. Now
> that e1000 uses napi_consume_skb() to put skbuff_heads of completed
> entries into the cache, it will never empty and always warm at that moment.
> Switch to the napi_build_skb() to relax mm pressure on heavy Rx and
> increase throughput.
>
> Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
> Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
> ---
> drivers/net/ethernet/intel/e1000/e1000_main.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
Tested-by: Tony Brelinski <tony.brelinski@intel.com>
^ permalink raw reply [flat|nested] 19+ messages in thread
end of thread, other threads:[~2021-12-28 0:07 UTC | newest]
Thread overview: 19+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-11-23 17:18 [PATCH net-next 0/9] intel: switch to napi_build_skb() Alexander Lobakin
2021-11-23 17:18 ` [PATCH net-next 1/9] e1000: switch to napi_consume_skb() Alexander Lobakin
2021-12-28 0:06 ` [Intel-wired-lan] " Brelinski, Tony
2021-11-23 17:18 ` [PATCH net-next 2/9] e1000: switch to napi_build_skb() Alexander Lobakin
2021-12-28 0:07 ` [Intel-wired-lan] " Brelinski, Tony
2021-11-23 17:18 ` [PATCH net-next 3/9] i40e: " Alexander Lobakin
2021-12-03 14:44 ` [Intel-wired-lan] " G, GurucharanX
2021-11-23 17:18 ` [PATCH net-next 4/9] iavf: " Alexander Lobakin
2021-12-14 12:50 ` [Intel-wired-lan] " Jankowski, Konrad0
2021-11-23 17:18 ` [PATCH net-next 5/9] ice: " Alexander Lobakin
2021-12-07 10:03 ` [Intel-wired-lan] " G, GurucharanX
2021-11-23 17:18 ` [PATCH net-next 6/9] igb: " Alexander Lobakin
2021-12-22 3:45 ` [Intel-wired-lan] " G, GurucharanX
2021-11-23 17:18 ` [PATCH net-next 7/9] igc: " Alexander Lobakin
2021-12-08 8:15 ` [Intel-wired-lan] " Kraus, NechamaX
2021-11-23 17:18 ` [PATCH net-next 8/9] ixgbe: " Alexander Lobakin
2021-12-03 14:45 ` [Intel-wired-lan] " G, GurucharanX
2021-11-23 17:18 ` [PATCH net-next 9/9] ixgbevf: " Alexander Lobakin
2021-12-12 13:47 ` [Intel-wired-lan] " Jankowski, Konrad0
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