[net-queue PATCH 0/5] i40e: stat counter updates and additions

[net-queue PATCH 0/5] i40e: stat counter updates and additions

[Joe Damato]

Greetings:

This patch set makes several updates to the i40e driver stats collection
and reporting code to help users of i40e get a better sense of how the
driver is performing and interacting with the rest of the kernel.

These patches include some new stats (like waived and busy) which were
inspired by other drivers that track stats using the same nomenclature.

The new stats and an existing stat, rx_reuse, are now accessible with
ethtool to make harvesting this data more convenient for users.

Joe Damato (5):
  i40e: Remove rx page reuse double count.
  i40e: Aggregate and export RX page reuse stat.
  i40e: Add a stat tracking new RX page allocations.
  i40e: Add a stat for tracking pages waived.
  i40e: Add a stat for tracking busy rx pages.

 drivers/net/ethernet/intel/i40e/i40e.h         |  4 ++++
 drivers/net/ethernet/intel/i40e/i40e_ethtool.c |  4 ++++
 drivers/net/ethernet/intel/i40e/i40e_main.c    | 14 +++++++++++++-
 drivers/net/ethernet/intel/i40e/i40e_txrx.c    | 25 ++++++++++++++++++-------
 drivers/net/ethernet/intel/i40e/i40e_txrx.h    |  3 +++
 5 files changed, 42 insertions(+), 8 deletions(-)

-- 
2.7.4

[net-queue PATCH 1/5] i40e: Remove rx page reuse double count.

[Joe Damato]

Page reuse was being tracked from two locations:
  - i40e_reuse_rx_page (via 40e_clean_rx_irq), and
  - i40e_alloc_mapped_page

Remove the double count and only count reuse from i40e_alloc_mapped_page
when the page is about to be reused.

Signed-off-by: Joe Damato <jdamato@fastly.com>
---
 drivers/net/ethernet/intel/i40e/i40e_txrx.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index 10a83e5..8b3ffb7 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -1382,8 +1382,6 @@ static void i40e_reuse_rx_page(struct i40e_ring *rx_ring,
 	new_buff->page_offset	= old_buff->page_offset;
 	new_buff->pagecnt_bias	= old_buff->pagecnt_bias;
 
-	rx_ring->rx_stats.page_reuse_count++;
-
 	/* clear contents of buffer_info */
 	old_buff->page = NULL;
 }
-- 
2.7.4

[net-queue PATCH 2/5] i40e: Aggregate and export RX page reuse stat.

[Joe Damato]

rx page reuse was already being tracked by the i40e driver per RX ring.
Aggregate the counts and make them accessible via ethtool.

Signed-off-by: Joe Damato <jdamato@fastly.com>
---
 drivers/net/ethernet/intel/i40e/i40e.h         | 1 +
 drivers/net/ethernet/intel/i40e/i40e_ethtool.c | 1 +
 drivers/net/ethernet/intel/i40e/i40e_main.c    | 5 ++++-
 3 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h
index 7f40f87..b61f17bf 100644
--- a/drivers/net/ethernet/intel/i40e/i40e.h
+++ b/drivers/net/ethernet/intel/i40e/i40e.h
@@ -853,6 +853,7 @@ struct i40e_vsi {
 	u64 tx_force_wb;
 	u64 rx_buf_failed;
 	u64 rx_page_failed;
+	u64 rx_page_reuse;
 
 	/* These are containers of ring pointers, allocated at run-time */
 	struct i40e_ring **rx_rings;
diff --git a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
index 513ba69..ceb0d5f 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
@@ -295,6 +295,7 @@ static const struct i40e_stats i40e_gstrings_misc_stats[] = {
 	I40E_VSI_STAT("tx_busy", tx_busy),
 	I40E_VSI_STAT("rx_alloc_fail", rx_buf_failed),
 	I40E_VSI_STAT("rx_pg_alloc_fail", rx_page_failed),
+	I40E_VSI_STAT("rx_cache_reuse", rx_page_reuse),
 };
 
 /* These PF_STATs might look like duplicates of some NETDEV_STATs,
diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 4ff1c9b..6d3b0bc 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -812,7 +812,7 @@ static void i40e_update_vsi_stats(struct i40e_vsi *vsi)
 	struct i40e_eth_stats *es;     /* device's eth stats */
 	u64 tx_restart, tx_busy;
 	struct i40e_ring *p;
-	u64 rx_page, rx_buf;
+	u64 rx_page, rx_buf, rx_reuse;
 	u64 bytes, packets;
 	unsigned int start;
 	u64 tx_linearize;
@@ -838,6 +838,7 @@ static void i40e_update_vsi_stats(struct i40e_vsi *vsi)
 	tx_restart = tx_busy = tx_linearize = tx_force_wb = 0;
 	rx_page = 0;
 	rx_buf = 0;
+	rx_reuse = 0;
 	rcu_read_lock();
 	for (q = 0; q < vsi->num_queue_pairs; q++) {
 		/* locate Tx ring */
@@ -871,6 +872,7 @@ static void i40e_update_vsi_stats(struct i40e_vsi *vsi)
 		rx_p += packets;
 		rx_buf += p->rx_stats.alloc_buff_failed;
 		rx_page += p->rx_stats.alloc_page_failed;
+		rx_reuse += p->rx_stats.page_reuse_count;
 
 		if (i40e_enabled_xdp_vsi(vsi)) {
 			/* locate XDP ring */
@@ -898,6 +900,7 @@ static void i40e_update_vsi_stats(struct i40e_vsi *vsi)
 	vsi->tx_force_wb = tx_force_wb;
 	vsi->rx_page_failed = rx_page;
 	vsi->rx_buf_failed = rx_buf;
+	vsi->rx_page_reuse = rx_reuse;
 
 	ns->rx_packets = rx_p;
 	ns->rx_bytes = rx_b;
-- 
2.7.4

[net-queue PATCH 3/5] i40e: Add a stat tracking new RX page allocations.

[Joe Damato]

Add a counter for new page allocations in the i40e RX path. This stat is
accessible with ethtool.

Signed-off-by: Joe Damato <jdamato@fastly.com>
---
 drivers/net/ethernet/intel/i40e/i40e.h         | 1 +
 drivers/net/ethernet/intel/i40e/i40e_ethtool.c | 1 +
 drivers/net/ethernet/intel/i40e/i40e_main.c    | 5 ++++-
 drivers/net/ethernet/intel/i40e/i40e_txrx.c    | 2 ++
 drivers/net/ethernet/intel/i40e/i40e_txrx.h    | 1 +
 5 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h
index b61f17bf..ab73de2 100644
--- a/drivers/net/ethernet/intel/i40e/i40e.h
+++ b/drivers/net/ethernet/intel/i40e/i40e.h
@@ -854,6 +854,7 @@ struct i40e_vsi {
 	u64 rx_buf_failed;
 	u64 rx_page_failed;
 	u64 rx_page_reuse;
+	u64 rx_page_alloc;
 
 	/* These are containers of ring pointers, allocated at run-time */
 	struct i40e_ring **rx_rings;
diff --git a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
index ceb0d5f..22f746b 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
@@ -296,6 +296,7 @@ static const struct i40e_stats i40e_gstrings_misc_stats[] = {
 	I40E_VSI_STAT("rx_alloc_fail", rx_buf_failed),
 	I40E_VSI_STAT("rx_pg_alloc_fail", rx_page_failed),
 	I40E_VSI_STAT("rx_cache_reuse", rx_page_reuse),
+	I40E_VSI_STAT("rx_cache_alloc", rx_page_alloc),
 };
 
 /* These PF_STATs might look like duplicates of some NETDEV_STATs,
diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 6d3b0bc..33c3f04 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -812,7 +812,7 @@ static void i40e_update_vsi_stats(struct i40e_vsi *vsi)
 	struct i40e_eth_stats *es;     /* device's eth stats */
 	u64 tx_restart, tx_busy;
 	struct i40e_ring *p;
-	u64 rx_page, rx_buf, rx_reuse;
+	u64 rx_page, rx_buf, rx_reuse, rx_alloc;
 	u64 bytes, packets;
 	unsigned int start;
 	u64 tx_linearize;
@@ -839,6 +839,7 @@ static void i40e_update_vsi_stats(struct i40e_vsi *vsi)
 	rx_page = 0;
 	rx_buf = 0;
 	rx_reuse = 0;
+	rx_reuse = 0;
 	rcu_read_lock();
 	for (q = 0; q < vsi->num_queue_pairs; q++) {
 		/* locate Tx ring */
@@ -873,6 +874,7 @@ static void i40e_update_vsi_stats(struct i40e_vsi *vsi)
 		rx_buf += p->rx_stats.alloc_buff_failed;
 		rx_page += p->rx_stats.alloc_page_failed;
 		rx_reuse += p->rx_stats.page_reuse_count;
+		rx_alloc += p->rx_stats.page_alloc_count;
 
 		if (i40e_enabled_xdp_vsi(vsi)) {
 			/* locate XDP ring */
@@ -901,6 +903,7 @@ static void i40e_update_vsi_stats(struct i40e_vsi *vsi)
 	vsi->rx_page_failed = rx_page;
 	vsi->rx_buf_failed = rx_buf;
 	vsi->rx_page_reuse = rx_reuse;
+	vsi->rx_page_alloc = rx_alloc;
 
 	ns->rx_packets = rx_p;
 	ns->rx_bytes = rx_b;
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index 8b3ffb7..1450efd 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -1671,6 +1671,8 @@ static bool i40e_alloc_mapped_page(struct i40e_ring *rx_ring,
 	if (unlikely(!page)) {
 		rx_ring->rx_stats.alloc_page_failed++;
 		return false;
+	} else {
+		rx_ring->rx_stats.page_alloc_count++;
 	}
 
 	/* map page for use */
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.h b/drivers/net/ethernet/intel/i40e/i40e_txrx.h
index bfc2845..7041e81 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.h
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.h
@@ -299,6 +299,7 @@ struct i40e_rx_queue_stats {
 	u64 alloc_buff_failed;
 	u64 page_reuse_count;
 	u64 realloc_count;
+	u64 page_alloc_count;
 };
 
 enum i40e_ring_state_t {
-- 
2.7.4

[net-queue PATCH 4/5] i40e: Add a stat for tracking pages waived.

[Joe Damato]

In some cases, pages can not be reused because they are not associated with
the correct NUMA zone. Knowing how often pages are waived helps users to
understand the interaction between the driver's memory usage and their
system.

Pass rx_stats through to i40e_can_reuse_rx_page to allow tracking when
pages are waived.

The page waive count is accessible via ethtool.

Signed-off-by: Joe Damato <jdamato@fastly.com>
---
 drivers/net/ethernet/intel/i40e/i40e.h         |  1 +
 drivers/net/ethernet/intel/i40e/i40e_ethtool.c |  1 +
 drivers/net/ethernet/intel/i40e/i40e_main.c    |  5 ++++-
 drivers/net/ethernet/intel/i40e/i40e_txrx.c    | 13 ++++++++++---
 drivers/net/ethernet/intel/i40e/i40e_txrx.h    |  1 +
 5 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h
index ab73de2..3774e7b 100644
--- a/drivers/net/ethernet/intel/i40e/i40e.h
+++ b/drivers/net/ethernet/intel/i40e/i40e.h
@@ -855,6 +855,7 @@ struct i40e_vsi {
 	u64 rx_page_failed;
 	u64 rx_page_reuse;
 	u64 rx_page_alloc;
+	u64 rx_page_waive;
 
 	/* These are containers of ring pointers, allocated at run-time */
 	struct i40e_ring **rx_rings;
diff --git a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
index 22f746b..224fe6d 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
@@ -297,6 +297,7 @@ static const struct i40e_stats i40e_gstrings_misc_stats[] = {
 	I40E_VSI_STAT("rx_pg_alloc_fail", rx_page_failed),
 	I40E_VSI_STAT("rx_cache_reuse", rx_page_reuse),
 	I40E_VSI_STAT("rx_cache_alloc", rx_page_alloc),
+	I40E_VSI_STAT("rx_cache_waive", rx_page_waive),
 };
 
 /* These PF_STATs might look like duplicates of some NETDEV_STATs,
diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 33c3f04..ded7aa9 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -812,7 +812,7 @@ static void i40e_update_vsi_stats(struct i40e_vsi *vsi)
 	struct i40e_eth_stats *es;     /* device's eth stats */
 	u64 tx_restart, tx_busy;
 	struct i40e_ring *p;
-	u64 rx_page, rx_buf, rx_reuse, rx_alloc;
+	u64 rx_page, rx_buf, rx_reuse, rx_alloc, rx_waive;
 	u64 bytes, packets;
 	unsigned int start;
 	u64 tx_linearize;
@@ -840,6 +840,7 @@ static void i40e_update_vsi_stats(struct i40e_vsi *vsi)
 	rx_buf = 0;
 	rx_reuse = 0;
 	rx_reuse = 0;
+	rx_waive = 0;
 	rcu_read_lock();
 	for (q = 0; q < vsi->num_queue_pairs; q++) {
 		/* locate Tx ring */
@@ -875,6 +876,7 @@ static void i40e_update_vsi_stats(struct i40e_vsi *vsi)
 		rx_page += p->rx_stats.alloc_page_failed;
 		rx_reuse += p->rx_stats.page_reuse_count;
 		rx_alloc += p->rx_stats.page_alloc_count;
+		rx_waive += p->rx_stats.page_waive_count;
 
 		if (i40e_enabled_xdp_vsi(vsi)) {
 			/* locate XDP ring */
@@ -904,6 +906,7 @@ static void i40e_update_vsi_stats(struct i40e_vsi *vsi)
 	vsi->rx_buf_failed = rx_buf;
 	vsi->rx_page_reuse = rx_reuse;
 	vsi->rx_page_alloc = rx_alloc;
+	vsi->rx_page_waive = rx_waive;
 
 	ns->rx_packets = rx_p;
 	ns->rx_bytes = rx_b;
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index 1450efd..c7ad983 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -1982,22 +1982,29 @@ static bool i40e_cleanup_headers(struct i40e_ring *rx_ring, struct sk_buff *skb,
 /**
  * i40e_can_reuse_rx_page - Determine if page can be reused for another Rx
  * @rx_buffer: buffer containing the page
+ * @rx_stats: rx stats structure for the rx ring
  * @rx_buffer_pgcnt: buffer page refcount pre xdp_do_redirect() call
  *
  * If page is reusable, we have a green light for calling i40e_reuse_rx_page,
  * which will assign the current buffer to the buffer that next_to_alloc is
  * pointing to; otherwise, the DMA mapping needs to be destroyed and
- * page freed
+ * page freed.
+ *
+ * rx_stats will be updated to indicate if the page was waived because it was
+ * not reusable.
  */
 static bool i40e_can_reuse_rx_page(struct i40e_rx_buffer *rx_buffer,
+				   struct i40e_rx_queue_stats *rx_stats,
 				   int rx_buffer_pgcnt)
 {
 	unsigned int pagecnt_bias = rx_buffer->pagecnt_bias;
 	struct page *page = rx_buffer->page;
 
 	/* Is any reuse possible? */
-	if (!dev_page_is_reusable(page))
+	if (!dev_page_is_reusable(page)) {
+		rx_stats->page_waive_count++;
 		return false;
+	}
 
 #if (PAGE_SIZE < 8192)
 	/* if we are only owner of page we can reuse it */
@@ -2237,7 +2244,7 @@ static void i40e_put_rx_buffer(struct i40e_ring *rx_ring,
 			       struct i40e_rx_buffer *rx_buffer,
 			       int rx_buffer_pgcnt)
 {
-	if (i40e_can_reuse_rx_page(rx_buffer, rx_buffer_pgcnt)) {
+	if (i40e_can_reuse_rx_page(rx_buffer, &rx_ring->rx_stats, rx_buffer_pgcnt)) {
 		/* hand second half of page back to the ring */
 		i40e_reuse_rx_page(rx_ring, rx_buffer);
 	} else {
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.h b/drivers/net/ethernet/intel/i40e/i40e_txrx.h
index 7041e81..e049cf48 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.h
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.h
@@ -300,6 +300,7 @@ struct i40e_rx_queue_stats {
 	u64 page_reuse_count;
 	u64 realloc_count;
 	u64 page_alloc_count;
+	u64 page_waive_count;
 };
 
 enum i40e_ring_state_t {
-- 
2.7.4

[net-queue PATCH 5/5] i40e: Add a stat for tracking busy rx pages.

[Joe Damato]

In some cases, pages cannot be reused by i40e because the page is busy. Add
a counter for this event.

Busy page count is accessible via ethtool.

Signed-off-by: Joe Damato <jdamato@fastly.com>
---
 drivers/net/ethernet/intel/i40e/i40e.h         |  1 +
 drivers/net/ethernet/intel/i40e/i40e_ethtool.c |  1 +
 drivers/net/ethernet/intel/i40e/i40e_main.c    |  5 ++++-
 drivers/net/ethernet/intel/i40e/i40e_txrx.c    | 12 ++++++++----
 drivers/net/ethernet/intel/i40e/i40e_txrx.h    |  1 +
 5 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h
index 3774e7b..b50530e 100644
--- a/drivers/net/ethernet/intel/i40e/i40e.h
+++ b/drivers/net/ethernet/intel/i40e/i40e.h
@@ -856,6 +856,7 @@ struct i40e_vsi {
 	u64 rx_page_reuse;
 	u64 rx_page_alloc;
 	u64 rx_page_waive;
+	u64 rx_page_busy;
 
 	/* These are containers of ring pointers, allocated at run-time */
 	struct i40e_ring **rx_rings;
diff --git a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
index 224fe6d..64fd869 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
@@ -298,6 +298,7 @@ static const struct i40e_stats i40e_gstrings_misc_stats[] = {
 	I40E_VSI_STAT("rx_cache_reuse", rx_page_reuse),
 	I40E_VSI_STAT("rx_cache_alloc", rx_page_alloc),
 	I40E_VSI_STAT("rx_cache_waive", rx_page_waive),
+	I40E_VSI_STAT("rx_cache_busy", rx_page_busy),
 };
 
 /* These PF_STATs might look like duplicates of some NETDEV_STATs,
diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index ded7aa9..1d9032c 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -812,7 +812,7 @@ static void i40e_update_vsi_stats(struct i40e_vsi *vsi)
 	struct i40e_eth_stats *es;     /* device's eth stats */
 	u64 tx_restart, tx_busy;
 	struct i40e_ring *p;
-	u64 rx_page, rx_buf, rx_reuse, rx_alloc, rx_waive;
+	u64 rx_page, rx_buf, rx_reuse, rx_alloc, rx_waive, rx_busy;
 	u64 bytes, packets;
 	unsigned int start;
 	u64 tx_linearize;
@@ -841,6 +841,7 @@ static void i40e_update_vsi_stats(struct i40e_vsi *vsi)
 	rx_reuse = 0;
 	rx_reuse = 0;
 	rx_waive = 0;
+	rx_busy = 0;
 	rcu_read_lock();
 	for (q = 0; q < vsi->num_queue_pairs; q++) {
 		/* locate Tx ring */
@@ -877,6 +878,7 @@ static void i40e_update_vsi_stats(struct i40e_vsi *vsi)
 		rx_reuse += p->rx_stats.page_reuse_count;
 		rx_alloc += p->rx_stats.page_alloc_count;
 		rx_waive += p->rx_stats.page_waive_count;
+		rx_busy += p->rx_stats.page_busy_count;
 
 		if (i40e_enabled_xdp_vsi(vsi)) {
 			/* locate XDP ring */
@@ -907,6 +909,7 @@ static void i40e_update_vsi_stats(struct i40e_vsi *vsi)
 	vsi->rx_page_reuse = rx_reuse;
 	vsi->rx_page_alloc = rx_alloc;
 	vsi->rx_page_waive = rx_waive;
+	vsi->rx_page_busy = rx_busy;
 
 	ns->rx_packets = rx_p;
 	ns->rx_bytes = rx_b;
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
index c7ad983..271697b 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c
@@ -1990,8 +1990,8 @@ static bool i40e_cleanup_headers(struct i40e_ring *rx_ring, struct sk_buff *skb,
  * pointing to; otherwise, the DMA mapping needs to be destroyed and
  * page freed.
  *
- * rx_stats will be updated to indicate if the page was waived because it was
- * not reusable.
+ * rx_stats will be updated to indicate whether the page was waived
+ * or busy if it could not be reused.
  */
 static bool i40e_can_reuse_rx_page(struct i40e_rx_buffer *rx_buffer,
 				   struct i40e_rx_queue_stats *rx_stats,
@@ -2008,13 +2008,17 @@ static bool i40e_can_reuse_rx_page(struct i40e_rx_buffer *rx_buffer,
 
 #if (PAGE_SIZE < 8192)
 	/* if we are only owner of page we can reuse it */
-	if (unlikely((rx_buffer_pgcnt - pagecnt_bias) > 1))
+	if (unlikely((rx_buffer_pgcnt - pagecnt_bias) > 1)) {
+		rx_stats->page_busy_count++;
 		return false;
+	}
 #else
 #define I40E_LAST_OFFSET \
 	(SKB_WITH_OVERHEAD(PAGE_SIZE) - I40E_RXBUFFER_2048)
-	if (rx_buffer->page_offset > I40E_LAST_OFFSET)
+	if (rx_buffer->page_offset > I40E_LAST_OFFSET) {
+		rx_stats->page_busy_count++;
 		return false;
+	}
 #endif
 
 	/* If we have drained the page fragment pool we need to update
diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.h b/drivers/net/ethernet/intel/i40e/i40e_txrx.h
index e049cf48..fd22e2f 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_txrx.h
+++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.h
@@ -301,6 +301,7 @@ struct i40e_rx_queue_stats {
 	u64 realloc_count;
 	u64 page_alloc_count;
 	u64 page_waive_count;
+	u64 page_busy_count;
 };
 
 enum i40e_ring_state_t {
-- 
2.7.4

Re: [net-queue PATCH 1/5] i40e: Remove rx page reuse double count.

[Jakub Kicinski]

On Tue, 14 Dec 2021 14:42:06 -0800 Joe Damato wrote:
> Page reuse was being tracked from two locations:
>   - i40e_reuse_rx_page (via 40e_clean_rx_irq), and
>   - i40e_alloc_mapped_page
> 
> Remove the double count and only count reuse from i40e_alloc_mapped_page
> when the page is about to be reused.
> 
> Signed-off-by: Joe Damato <jdamato@fastly.com>

Possibly a fix, this one?

Re: [net-queue PATCH 0/5] i40e: stat counter updates and additions

[Jakub Kicinski]

On Tue, 14 Dec 2021 14:42:05 -0800 Joe Damato wrote:
> This patch set makes several updates to the i40e driver stats collection
> and reporting code to help users of i40e get a better sense of how the
> driver is performing and interacting with the rest of the kernel.
> 
> These patches include some new stats (like waived and busy) which were
> inspired by other drivers that track stats using the same nomenclature.
> 
> The new stats and an existing stat, rx_reuse, are now accessible with
> ethtool to make harvesting this data more convenient for users.

Looks good overall, thanks.