[PATCH net-next] gve: Remove qpl_cfg struct since qpl_ids map with queues respectively

From: Ziwei Xiao
Date: Wed Apr 17 2024 - 16:58:25 EST

The qpl_cfg struct was used to make sure that no two different queues
are using QPL with the same qpl_id. We can remove that qpl_cfg struct
since now the qpl_ids map with the queues respectively as follows:
For tx queues: qpl_id = tx_qid
For rx queues: qpl_id = max_tx_queues + rx_qid

And when XDP is used, it will need the user to reduce the tx queues to
be at most half of the max_tx_queues. Then it will use the same number
of tx queues starting from the end of existing tx queues for XDP. So the
XDP queues will not exceed the max_tx_queues range and will not overlap
with the rx queues, where the qpl_ids will not have overlapping too.

Considering of that, we remove the qpl_cfg struct to get the qpl_id
directly based on the queue id. Unless we are erroneously allocating a
rx/tx queue that has already been allocated, we would never allocate
the qpl with the same qpl_id twice. In that case, it should fail much
earlier than the QPL assignment.

Suggested-by: Praveen Kaligineedi <pkaligineedi@xxxxxxxxxx>
Signed-off-by: Ziwei Xiao <ziweixiao@xxxxxxxxxx>
Reviewed-by: Harshitha Ramamurthy <hramamurthy@xxxxxxxxxx>
Reviewed-by: Shailend Chand <shailend@xxxxxxxxxx>
---
drivers/net/ethernet/google/gve/gve.h | 39 +------------------
drivers/net/ethernet/google/gve/gve_ethtool.c | 9 -----
drivers/net/ethernet/google/gve/gve_main.c | 38 +-----------------
drivers/net/ethernet/google/gve/gve_rx.c | 12 ++----
drivers/net/ethernet/google/gve/gve_rx_dqo.c | 12 +++---
drivers/net/ethernet/google/gve/gve_tx.c | 12 ++----
drivers/net/ethernet/google/gve/gve_tx_dqo.c | 11 ++----
7 files changed, 20 insertions(+), 113 deletions(-)

diff --git a/drivers/net/ethernet/google/gve/gve.h b/drivers/net/ethernet/google/gve/gve.h
index e97633b68e25..53b5244dc7bc 100644
--- a/drivers/net/ethernet/google/gve/gve.h
+++ b/drivers/net/ethernet/google/gve/gve.h
@@ -639,7 +639,6 @@ struct gve_ptype_lut {

/* Parameters for allocating queue page lists */
struct gve_qpls_alloc_cfg {
- struct gve_qpl_config *qpl_cfg;
struct gve_queue_config *tx_cfg;
struct gve_queue_config *rx_cfg;

@@ -655,9 +654,8 @@ struct gve_qpls_alloc_cfg {
struct gve_tx_alloc_rings_cfg {
struct gve_queue_config *qcfg;

- /* qpls and qpl_cfg must already be allocated */
+ /* qpls must already be allocated */
struct gve_queue_page_list *qpls;
- struct gve_qpl_config *qpl_cfg;

u16 ring_size;
u16 start_idx;
@@ -674,9 +672,8 @@ struct gve_rx_alloc_rings_cfg {
struct gve_queue_config *qcfg;
struct gve_queue_config *qcfg_tx;

- /* qpls and qpl_cfg must already be allocated */
+ /* qpls must already be allocated */
struct gve_queue_page_list *qpls;
- struct gve_qpl_config *qpl_cfg;

u16 ring_size;
u16 packet_buffer_size;
@@ -732,7 +729,6 @@ struct gve_priv {
u16 num_xdp_queues;
struct gve_queue_config tx_cfg;
struct gve_queue_config rx_cfg;
- struct gve_qpl_config qpl_cfg; /* map used QPL ids */
u32 num_ntfy_blks; /* spilt between TX and RX so must be even */

struct gve_registers __iomem *reg_bar0; /* see gve_register.h */
@@ -1053,37 +1049,6 @@ static inline u32 gve_get_rx_pages_per_qpl_dqo(u32 rx_desc_cnt)
return 2 * rx_desc_cnt;
}

-/* Returns a pointer to the next available tx qpl in the list of qpls */
-static inline
-struct gve_queue_page_list *gve_assign_tx_qpl(struct gve_tx_alloc_rings_cfg *cfg,
- int tx_qid)
-{
- /* QPL already in use */
- if (test_bit(tx_qid, cfg->qpl_cfg->qpl_id_map))
- return NULL;
- set_bit(tx_qid, cfg->qpl_cfg->qpl_id_map);
- return &cfg->qpls[tx_qid];
-}
-
-/* Returns a pointer to the next available rx qpl in the list of qpls */
-static inline
-struct gve_queue_page_list *gve_assign_rx_qpl(struct gve_rx_alloc_rings_cfg *cfg,
- int rx_qid)
-{
- int id = gve_get_rx_qpl_id(cfg->qcfg_tx, rx_qid);
- /* QPL already in use */
- if (test_bit(id, cfg->qpl_cfg->qpl_id_map))
- return NULL;
- set_bit(id, cfg->qpl_cfg->qpl_id_map);
- return &cfg->qpls[id];
-}
-
-/* Unassigns the qpl with the given id */
-static inline void gve_unassign_qpl(struct gve_qpl_config *qpl_cfg, int id)
-{
- clear_bit(id, qpl_cfg->qpl_id_map);
-}
-
/* Returns the correct dma direction for tx and rx qpls */
static inline enum dma_data_direction gve_qpl_dma_dir(struct gve_priv *priv,
int id)
diff --git a/drivers/net/ethernet/google/gve/gve_ethtool.c b/drivers/net/ethernet/google/gve/gve_ethtool.c
index 299206d15c73..bd7632eed776 100644
--- a/drivers/net/ethernet/google/gve/gve_ethtool.c
+++ b/drivers/net/ethernet/google/gve/gve_ethtool.c
@@ -510,7 +510,6 @@ static int gve_adjust_ring_sizes(struct gve_priv *priv,
struct gve_tx_alloc_rings_cfg tx_alloc_cfg = {0};
struct gve_rx_alloc_rings_cfg rx_alloc_cfg = {0};
struct gve_qpls_alloc_cfg qpls_alloc_cfg = {0};
- struct gve_qpl_config new_qpl_cfg;
int err;

/* get current queue configuration */
@@ -521,14 +520,6 @@ static int gve_adjust_ring_sizes(struct gve_priv *priv,
tx_alloc_cfg.ring_size = new_tx_desc_cnt;
rx_alloc_cfg.ring_size = new_rx_desc_cnt;

- /* qpl_cfg is not read-only, it contains a map that gets updated as
- * rings are allocated, which is why we cannot use the yet unreleased
- * one in priv.
- */
- qpls_alloc_cfg.qpl_cfg = &new_qpl_cfg;
- tx_alloc_cfg.qpl_cfg = &new_qpl_cfg;
- rx_alloc_cfg.qpl_cfg = &new_qpl_cfg;
-
if (netif_running(priv->dev)) {
err = gve_adjust_config(priv, &qpls_alloc_cfg,
&tx_alloc_cfg, &rx_alloc_cfg);
diff --git a/drivers/net/ethernet/google/gve/gve_main.c b/drivers/net/ethernet/google/gve/gve_main.c
index a515e5af843c..61039e3dd2bb 100644
--- a/drivers/net/ethernet/google/gve/gve_main.c
+++ b/drivers/net/ethernet/google/gve/gve_main.c
@@ -829,7 +829,6 @@ static void gve_tx_get_curr_alloc_cfg(struct gve_priv *priv,
cfg->qcfg = &priv->tx_cfg;
cfg->raw_addressing = !gve_is_qpl(priv);
cfg->qpls = priv->qpls;
- cfg->qpl_cfg = &priv->qpl_cfg;
cfg->ring_size = priv->tx_desc_cnt;
cfg->start_idx = 0;
cfg->num_rings = gve_num_tx_queues(priv);
@@ -1119,22 +1118,13 @@ static int gve_alloc_qpls(struct gve_priv *priv, struct gve_qpls_alloc_cfg *cfg,
if (!qpls)
return -ENOMEM;

- cfg->qpl_cfg->qpl_map_size = BITS_TO_LONGS(max_queues) *
- sizeof(unsigned long) * BITS_PER_BYTE;
- cfg->qpl_cfg->qpl_id_map = kvcalloc(BITS_TO_LONGS(max_queues),
- sizeof(unsigned long), GFP_KERNEL);
- if (!cfg->qpl_cfg->qpl_id_map) {
- err = -ENOMEM;
- goto free_qpl_array;
- }
-
/* Allocate TX QPLs */
page_count = priv->tx_pages_per_qpl;
tx_num_qpls = gve_num_tx_qpls(cfg->tx_cfg, cfg->num_xdp_queues,
gve_is_qpl(priv));
err = gve_alloc_n_qpls(priv, qpls, page_count, 0, tx_num_qpls);
if (err)
- goto free_qpl_map;
+ goto free_qpl_array;

/* Allocate RX QPLs */
rx_start_id = gve_rx_start_qpl_id(cfg->tx_cfg);
@@ -1157,9 +1147,6 @@ static int gve_alloc_qpls(struct gve_priv *priv, struct gve_qpls_alloc_cfg *cfg,

free_tx_qpls:
gve_free_n_qpls(priv, qpls, 0, tx_num_qpls);
-free_qpl_map:
- kvfree(cfg->qpl_cfg->qpl_id_map);
- cfg->qpl_cfg->qpl_id_map = NULL;
free_qpl_array:
kvfree(qpls);
return err;
@@ -1175,9 +1162,6 @@ static void gve_free_qpls(struct gve_priv *priv,
if (!qpls)
return;

- kvfree(cfg->qpl_cfg->qpl_id_map);
- cfg->qpl_cfg->qpl_id_map = NULL;
-
for (i = 0; i < max_queues; i++)
gve_free_queue_page_list(priv, &qpls[i], i);

@@ -1292,7 +1276,6 @@ static void gve_qpls_get_curr_alloc_cfg(struct gve_priv *priv,
cfg->raw_addressing = !gve_is_qpl(priv);
cfg->is_gqi = gve_is_gqi(priv);
cfg->num_xdp_queues = priv->num_xdp_queues;
- cfg->qpl_cfg = &priv->qpl_cfg;
cfg->tx_cfg = &priv->tx_cfg;
cfg->rx_cfg = &priv->rx_cfg;
cfg->qpls = priv->qpls;
@@ -1306,7 +1289,6 @@ static void gve_rx_get_curr_alloc_cfg(struct gve_priv *priv,
cfg->raw_addressing = !gve_is_qpl(priv);
cfg->enable_header_split = priv->header_split_enabled;
cfg->qpls = priv->qpls;
- cfg->qpl_cfg = &priv->qpl_cfg;
cfg->ring_size = priv->rx_desc_cnt;
cfg->packet_buffer_size = gve_is_gqi(priv) ?
GVE_DEFAULT_RX_BUFFER_SIZE :
@@ -1419,7 +1401,6 @@ static int gve_queues_start(struct gve_priv *priv,
priv->rx = rx_alloc_cfg->rx;

/* Record new configs into priv */
- priv->qpl_cfg = *qpls_alloc_cfg->qpl_cfg;
priv->tx_cfg = *tx_alloc_cfg->qcfg;
priv->rx_cfg = *rx_alloc_cfg->qcfg;
priv->tx_desc_cnt = tx_alloc_cfg->ring_size;
@@ -1916,20 +1897,11 @@ int gve_adjust_queues(struct gve_priv *priv,
struct gve_tx_alloc_rings_cfg tx_alloc_cfg = {0};
struct gve_rx_alloc_rings_cfg rx_alloc_cfg = {0};
struct gve_qpls_alloc_cfg qpls_alloc_cfg = {0};
- struct gve_qpl_config new_qpl_cfg;
int err;

gve_get_curr_alloc_cfgs(priv, &qpls_alloc_cfg,
&tx_alloc_cfg, &rx_alloc_cfg);

- /* qpl_cfg is not read-only, it contains a map that gets updated as
- * rings are allocated, which is why we cannot use the yet unreleased
- * one in priv.
- */
- qpls_alloc_cfg.qpl_cfg = &new_qpl_cfg;
- tx_alloc_cfg.qpl_cfg = &new_qpl_cfg;
- rx_alloc_cfg.qpl_cfg = &new_qpl_cfg;
-
/* Relay the new config from ethtool */
qpls_alloc_cfg.tx_cfg = &new_tx_config;
tx_alloc_cfg.qcfg = &new_tx_config;
@@ -2121,18 +2093,10 @@ static int gve_set_features(struct net_device *netdev,
struct gve_rx_alloc_rings_cfg rx_alloc_cfg = {0};
struct gve_qpls_alloc_cfg qpls_alloc_cfg = {0};
struct gve_priv *priv = netdev_priv(netdev);
- struct gve_qpl_config new_qpl_cfg;
int err;

gve_get_curr_alloc_cfgs(priv, &qpls_alloc_cfg,
&tx_alloc_cfg, &rx_alloc_cfg);
- /* qpl_cfg is not read-only, it contains a map that gets updated as
- * rings are allocated, which is why we cannot use the yet unreleased
- * one in priv.
- */
- qpls_alloc_cfg.qpl_cfg = &new_qpl_cfg;
- tx_alloc_cfg.qpl_cfg = &new_qpl_cfg;
- rx_alloc_cfg.qpl_cfg = &new_qpl_cfg;

if ((netdev->features & NETIF_F_LRO) != (features & NETIF_F_LRO)) {
netdev->features ^= NETIF_F_LRO;
diff --git a/drivers/net/ethernet/google/gve/gve_rx.c b/drivers/net/ethernet/google/gve/gve_rx.c
index cd727e55ae0f..9b56e89c4f43 100644
--- a/drivers/net/ethernet/google/gve/gve_rx.c
+++ b/drivers/net/ethernet/google/gve/gve_rx.c
@@ -38,7 +38,6 @@ static void gve_rx_unfill_pages(struct gve_priv *priv,
for (i = 0; i < slots; i++)
page_ref_sub(rx->data.page_info[i].page,
rx->data.page_info[i].pagecnt_bias - 1);
- gve_unassign_qpl(cfg->qpl_cfg, rx->data.qpl->id);
rx->data.qpl = NULL;

for (i = 0; i < rx->qpl_copy_pool_mask + 1; i++) {
@@ -145,13 +144,11 @@ static int gve_rx_prefill_pages(struct gve_rx_ring *rx,
return -ENOMEM;

if (!rx->data.raw_addressing) {
- rx->data.qpl = gve_assign_rx_qpl(cfg, rx->q_num);
- if (!rx->data.qpl) {
- kvfree(rx->data.page_info);
- rx->data.page_info = NULL;
- return -ENOMEM;
- }
+ u32 qpl_id = gve_get_rx_qpl_id(cfg->qcfg_tx, rx->q_num);
+
+ rx->data.qpl = &cfg->qpls[qpl_id];
}
+
for (i = 0; i < slots; i++) {
if (!rx->data.raw_addressing) {
struct page *page = rx->data.qpl->pages[i];
@@ -204,7 +201,6 @@ static int gve_rx_prefill_pages(struct gve_rx_ring *rx,
page_ref_sub(rx->data.page_info[i].page,
rx->data.page_info[i].pagecnt_bias - 1);

- gve_unassign_qpl(cfg->qpl_cfg, rx->data.qpl->id);
rx->data.qpl = NULL;

return err;
diff --git a/drivers/net/ethernet/google/gve/gve_rx_dqo.c b/drivers/net/ethernet/google/gve/gve_rx_dqo.c
index 15108407b54f..53fd2d87233f 100644
--- a/drivers/net/ethernet/google/gve/gve_rx_dqo.c
+++ b/drivers/net/ethernet/google/gve/gve_rx_dqo.c
@@ -247,10 +247,8 @@ static void gve_rx_free_ring_dqo(struct gve_priv *priv, struct gve_rx_ring *rx,
if (bs->page_info.page)
gve_free_page_dqo(priv, bs, !rx->dqo.qpl);
}
- if (rx->dqo.qpl) {
- gve_unassign_qpl(cfg->qpl_cfg, rx->dqo.qpl->id);
- rx->dqo.qpl = NULL;
- }
+
+ rx->dqo.qpl = NULL;

if (rx->dqo.bufq.desc_ring) {
size = sizeof(rx->dqo.bufq.desc_ring[0]) * buffer_queue_slots;
@@ -359,9 +357,9 @@ static int gve_rx_alloc_ring_dqo(struct gve_priv *priv,
goto err;

if (!cfg->raw_addressing) {
- rx->dqo.qpl = gve_assign_rx_qpl(cfg, rx->q_num);
- if (!rx->dqo.qpl)
- goto err;
+ u32 qpl_id = gve_get_rx_qpl_id(cfg->qcfg_tx, rx->q_num);
+
+ rx->dqo.qpl = &cfg->qpls[qpl_id];
rx->dqo.next_qpl_page_idx = 0;
}

diff --git a/drivers/net/ethernet/google/gve/gve_tx.c b/drivers/net/ethernet/google/gve/gve_tx.c
index 4b9853adc113..f805700d67e7 100644
--- a/drivers/net/ethernet/google/gve/gve_tx.c
+++ b/drivers/net/ethernet/google/gve/gve_tx.c
@@ -225,7 +225,6 @@ static void gve_tx_free_ring_gqi(struct gve_priv *priv, struct gve_tx_ring *tx,

if (!tx->raw_addressing) {
gve_tx_fifo_release(priv, &tx->tx_fifo);
- gve_unassign_qpl(cfg->qpl_cfg, tx->tx_fifo.qpl->id);
tx->tx_fifo.qpl = NULL;
}

@@ -280,12 +279,12 @@ static int gve_tx_alloc_ring_gqi(struct gve_priv *priv,
tx->raw_addressing = cfg->raw_addressing;
tx->dev = hdev;
if (!tx->raw_addressing) {
- tx->tx_fifo.qpl = gve_assign_tx_qpl(cfg, idx);
- if (!tx->tx_fifo.qpl)
- goto abort_with_desc;
+ u32 qpl_id = gve_tx_qpl_id(priv, tx->q_num);
+
+ tx->tx_fifo.qpl = &cfg->qpls[qpl_id];
/* map Tx FIFO */
if (gve_tx_fifo_init(priv, &tx->tx_fifo))
- goto abort_with_qpl;
+ goto abort_with_desc;
}

tx->q_resources =
@@ -301,9 +300,6 @@ static int gve_tx_alloc_ring_gqi(struct gve_priv *priv,
abort_with_fifo:
if (!tx->raw_addressing)
gve_tx_fifo_release(priv, &tx->tx_fifo);
-abort_with_qpl:
- if (!tx->raw_addressing)
- gve_unassign_qpl(cfg->qpl_cfg, tx->tx_fifo.qpl->id);
abort_with_desc:
dma_free_coherent(hdev, bytes, tx->desc, tx->bus);
tx->desc = NULL;
diff --git a/drivers/net/ethernet/google/gve/gve_tx_dqo.c b/drivers/net/ethernet/google/gve/gve_tx_dqo.c
index 70f29b90a982..3d825e406c4b 100644
--- a/drivers/net/ethernet/google/gve/gve_tx_dqo.c
+++ b/drivers/net/ethernet/google/gve/gve_tx_dqo.c
@@ -236,10 +236,7 @@ static void gve_tx_free_ring_dqo(struct gve_priv *priv, struct gve_tx_ring *tx,
kvfree(tx->dqo.tx_qpl_buf_next);
tx->dqo.tx_qpl_buf_next = NULL;

- if (tx->dqo.qpl) {
- gve_unassign_qpl(cfg->qpl_cfg, tx->dqo.qpl->id);
- tx->dqo.qpl = NULL;
- }
+ tx->dqo.qpl = NULL;

netif_dbg(priv, drv, priv->dev, "freed tx queue %d\n", idx);
}
@@ -352,9 +349,9 @@ static int gve_tx_alloc_ring_dqo(struct gve_priv *priv,
goto err;

if (!cfg->raw_addressing) {
- tx->dqo.qpl = gve_assign_tx_qpl(cfg, idx);
- if (!tx->dqo.qpl)
- goto err;
+ u32 qpl_id = gve_tx_qpl_id(priv, tx->q_num);
+
+ tx->dqo.qpl = &cfg->qpls[qpl_id];

if (gve_tx_qpl_buf_init(tx))
goto err;
--
2.44.0.769.g3c40516874-goog