Add a new 'retain_page_pool' flag to am65_cpsw_destroy_rxq/s()
so that the page pool allocation is retained  while
switching XDP program. This will avoid requiring
any re-allocation and potential failures during low memory
conditions.

Signed-off-by: Roger Quadros <[email protected]>
---
 drivers/net/ethernet/ti/am65-cpsw-nuss.c | 38 ++++++++++++++++++--------------
 1 file changed, 22 insertions(+), 16 deletions(-)

diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c 
b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
index 
f8beb1735fb9cb75577e60f5b22111cb3a66acb9..f9e2286efa29bbb7056fda1fc82c38b479aae8bd
 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
+++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
@@ -505,7 +505,7 @@ static inline void am65_cpsw_put_page(struct 
am65_cpsw_rx_flow *flow,
 static void am65_cpsw_nuss_rx_cleanup(void *data, dma_addr_t desc_dma);
 static void am65_cpsw_nuss_tx_cleanup(void *data, dma_addr_t desc_dma);
 
-static void am65_cpsw_destroy_rxq(struct am65_cpsw_common *common, int id)
+static void am65_cpsw_destroy_rxq(struct am65_cpsw_common *common, int id, 
bool retain_page_pool)
 {
        struct am65_cpsw_rx_chn *rx_chn = &common->rx_chns;
        struct am65_cpsw_rx_flow *flow;
@@ -528,13 +528,13 @@ static void am65_cpsw_destroy_rxq(struct am65_cpsw_common 
*common, int id)
                        xdp_rxq_info_unreg(rxq);
        }
 
-       if (flow->page_pool) {
+       if (flow->page_pool && !retain_page_pool) {
                page_pool_destroy(flow->page_pool);
                flow->page_pool = NULL;
        }
 }
 
-static void am65_cpsw_destroy_rxqs(struct am65_cpsw_common *common)
+static void am65_cpsw_destroy_rxqs(struct am65_cpsw_common *common, bool 
retain_page_pool)
 {
        struct am65_cpsw_rx_chn *rx_chn = &common->rx_chns;
        int id;
@@ -549,7 +549,7 @@ static void am65_cpsw_destroy_rxqs(struct am65_cpsw_common 
*common)
        }
 
        for (id = common->rx_ch_num_flows - 1; id >= 0; id--)
-               am65_cpsw_destroy_rxq(common, id);
+               am65_cpsw_destroy_rxq(common, id, retain_page_pool);
 
        k3_udma_glue_disable_rx_chn(common->rx_chns.rx_chn);
 }
@@ -574,13 +574,18 @@ static int am65_cpsw_create_rxq(struct am65_cpsw_common 
*common, int id)
 
        flow = &rx_chn->flows[id];
        pp_params.napi = &flow->napi_rx;
-       pool = page_pool_create(&pp_params);
-       if (IS_ERR(pool)) {
-               ret = PTR_ERR(pool);
-               return ret;
-       }
 
-       flow->page_pool = pool;
+       if (!flow->page_pool) {
+               pool = page_pool_create(&pp_params);
+               if (IS_ERR(pool)) {
+                       ret = PTR_ERR(pool);
+                       return ret;
+               }
+
+               flow->page_pool = pool;
+       } else {
+               pool = flow->page_pool;
+       }
 
        /* using same page pool is allowed as no running rx handlers
         * simultaneously for both ndevs
@@ -626,7 +631,7 @@ static int am65_cpsw_create_rxq(struct am65_cpsw_common 
*common, int id)
        return 0;
 
 err:
-       am65_cpsw_destroy_rxq(common, id);
+       am65_cpsw_destroy_rxq(common, id, false);
        return ret;
 }
 
@@ -653,7 +658,7 @@ static int am65_cpsw_create_rxqs(struct am65_cpsw_common 
*common)
 
 err:
        for (--id; id >= 0; id--)
-               am65_cpsw_destroy_rxq(common, id);
+               am65_cpsw_destroy_rxq(common, id, false);
 
        return ret;
 }
@@ -942,7 +947,7 @@ static int am65_cpsw_nuss_common_open(struct 
am65_cpsw_common *common)
        return 0;
 
 cleanup_rx:
-       am65_cpsw_destroy_rxqs(common);
+       am65_cpsw_destroy_rxqs(common, false);
 
        return ret;
 }
@@ -956,7 +961,7 @@ static int am65_cpsw_nuss_common_stop(struct 
am65_cpsw_common *common)
                             ALE_PORT_STATE, ALE_PORT_STATE_DISABLE);
 
        am65_cpsw_destroy_txqs(common);
-       am65_cpsw_destroy_rxqs(common);
+       am65_cpsw_destroy_rxqs(common, false);
        cpsw_ale_stop(common->ale);
 
        writel(0, common->cpsw_base + AM65_CPSW_REG_CTL);
@@ -1927,7 +1932,8 @@ static int am65_cpsw_xdp_prog_setup(struct net_device 
*ndev,
        if (running) {
                /* stop all queues */
                am65_cpsw_destroy_txqs(common);
-               am65_cpsw_destroy_rxqs(common);
+               /* Retain page pool */
+               am65_cpsw_destroy_rxqs(common, true);
        }
 
        old_prog = xchg(&port->xdp_prog, prog);
@@ -1942,7 +1948,7 @@ static int am65_cpsw_xdp_prog_setup(struct net_device 
*ndev,
 
                ret = am65_cpsw_create_txqs(common);
                if (ret) {
-                       am65_cpsw_destroy_rxqs(common);
+                       am65_cpsw_destroy_rxqs(common, false);
                        return ret;
                }
        }

-- 
2.34.1

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