Commit b537633ce57b for kernel

commit b537633ce57b29f4c9687fea6f2d92e1ca7853fc
Author: Taehee Yoo <ap420073@gmail.com>
Date:   Sun Jul 21 05:35:54 2024 +0000

    bnxt_en: update xdp_rxq_info in queue restart logic

    When the netdev_rx_queue_restart() restarts queues, the bnxt_en driver
    updates(creates and deletes) a page_pool.
    But it doesn't update xdp_rxq_info, so the xdp_rxq_info is still
    connected to an old page_pool.
    So, bnxt_rx_ring_info->page_pool indicates a new page_pool, but
    bnxt_rx_ring_info->xdp_rxq is still connected to an old page_pool.

    An old page_pool is no longer used so it is supposed to be
    deleted by page_pool_destroy() but it isn't.
    Because the xdp_rxq_info is holding the reference count for it and the
    xdp_rxq_info is not updated, an old page_pool will not be deleted in
    the queue restart logic.

    Before restarting 1 queue:
    ./tools/net/ynl/samples/page-pool
    enp10s0f1np1[6] page pools: 4 (zombies: 0)
            refs: 8192 bytes: 33554432 (refs: 0 bytes: 0)
            recycling: 0.0% (alloc: 128:8048 recycle: 0:0)

    After restarting 1 queue:
    ./tools/net/ynl/samples/page-pool
    enp10s0f1np1[6] page pools: 5 (zombies: 0)
            refs: 10240 bytes: 41943040 (refs: 0 bytes: 0)
            recycling: 20.0% (alloc: 160:10080 recycle: 1920:128)

    Before restarting queues, an interface has 4 page_pools.
    After restarting one queue, an interface has 5 page_pools, but it
    should be 4, not 5.
    The reason is that queue restarting logic creates a new page_pool and
    an old page_pool is not deleted due to the absence of an update of
    xdp_rxq_info logic.

    Fixes: 2d694c27d32e ("bnxt_en: implement netdev_queue_mgmt_ops")
    Signed-off-by: Taehee Yoo <ap420073@gmail.com>
    Reviewed-by: David Wei <dw@davidwei.uk>
    Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
    Link: https://patch.msgid.link/20240721053554.1233549-1-ap420073@gmail.com
    Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index bb3be33c1bbd..ffa74c26ee53 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -4052,6 +4052,7 @@ static void bnxt_reset_rx_ring_struct(struct bnxt *bp,

 	rxr->page_pool->p.napi = NULL;
 	rxr->page_pool = NULL;
+	memset(&rxr->xdp_rxq, 0, sizeof(struct xdp_rxq_info));

 	ring = &rxr->rx_ring_struct;
 	rmem = &ring->ring_mem;
@@ -15018,6 +15019,16 @@ static int bnxt_queue_mem_alloc(struct net_device *dev, void *qmem, int idx)
 	if (rc)
 		return rc;

+	rc = xdp_rxq_info_reg(&clone->xdp_rxq, bp->dev, idx, 0);
+	if (rc < 0)
+		goto err_page_pool_destroy;
+
+	rc = xdp_rxq_info_reg_mem_model(&clone->xdp_rxq,
+					MEM_TYPE_PAGE_POOL,
+					clone->page_pool);
+	if (rc)
+		goto err_rxq_info_unreg;
+
 	ring = &clone->rx_ring_struct;
 	rc = bnxt_alloc_ring(bp, &ring->ring_mem);
 	if (rc)
@@ -15047,6 +15058,9 @@ static int bnxt_queue_mem_alloc(struct net_device *dev, void *qmem, int idx)
 	bnxt_free_ring(bp, &clone->rx_agg_ring_struct.ring_mem);
 err_free_rx_ring:
 	bnxt_free_ring(bp, &clone->rx_ring_struct.ring_mem);
+err_rxq_info_unreg:
+	xdp_rxq_info_unreg(&clone->xdp_rxq);
+err_page_pool_destroy:
 	clone->page_pool->p.napi = NULL;
 	page_pool_destroy(clone->page_pool);
 	clone->page_pool = NULL;
@@ -15062,6 +15076,8 @@ static void bnxt_queue_mem_free(struct net_device *dev, void *qmem)
 	bnxt_free_one_rx_ring(bp, rxr);
 	bnxt_free_one_rx_agg_ring(bp, rxr);

+	xdp_rxq_info_unreg(&rxr->xdp_rxq);
+
 	page_pool_destroy(rxr->page_pool);
 	rxr->page_pool = NULL;

@@ -15145,6 +15161,7 @@ static int bnxt_queue_start(struct net_device *dev, void *qmem, int idx)
 	rxr->rx_sw_agg_prod = clone->rx_sw_agg_prod;
 	rxr->rx_next_cons = clone->rx_next_cons;
 	rxr->page_pool = clone->page_pool;
+	rxr->xdp_rxq = clone->xdp_rxq;

 	bnxt_copy_rx_ring(bp, rxr, clone);