On 1/13/26 10:27, Paolo Abeni wrote:
On 1/9/26 12:28 PM, Pavel Begunkov wrote:
From: Jakub Kicinski <[email protected]>
The driver tries to provision more agg buffers than header buffers
since multiple agg segments can reuse the same header. The calculation
/ heuristic tries to provide enough pages for 65k of data for each header
(or 4 frags per header if the result is too big). This calculation is
currently global to the adapter. If we increase the buffer sizes 8x
we don't want 8x the amount of memory sitting on the rings.
Luckily we don't have to fill the rings completely, adjust
the fill level dynamically in case particular queue has buffers
larger than the global size.
Signed-off-by: Jakub Kicinski <[email protected]>
[pavel: rebase on top of agg_size_fac, assert agg_size_fac]
Signed-off-by: Pavel Begunkov <[email protected]>
---
drivers/net/ethernet/broadcom/bnxt/bnxt.c | 28 +++++++++++++++++++----
1 file changed, 24 insertions(+), 4 deletions(-)
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 8f42885a7c86..137e348d2b9c 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -3816,16 +3816,34 @@ static void bnxt_free_rx_rings(struct bnxt *bp)
}
}
+static int bnxt_rx_agg_ring_fill_level(struct bnxt *bp,
+ struct bnxt_rx_ring_info *rxr)
+{
+ /* User may have chosen larger than default rx_page_size,
+ * we keep the ring sizes uniform and also want uniform amount
+ * of bytes consumed per ring, so cap how much of the rings we fill.
+ */
+ int fill_level = bp->rx_agg_ring_size;
+
+ if (rxr->rx_page_size > BNXT_RX_PAGE_SIZE)
+ fill_level /= rxr->rx_page_size / BNXT_RX_PAGE_SIZE;
According to the check in bnxt_alloc_rx_page_pool() it's theoretically
possible for `rxr->rx_page_size / BNXT_RX_PAGE_SIZE` being zero. If so
the above would crash.
Side note: this looks like something AI review could/should catch. The
fact it didn't makes me think I'm missing something...
I doubt LLMs will be able to see it, but rx_page_size is no less
than BNXT_RX_PAGE_SIZE. It's either set from defaults, which is
exactly BNXT_RX_PAGE_SIZE, or given by the provider and then
checked in bnxt_validate_qcfg().
--
Pavel Begunkov
