[PATCH v3 net-next 5/8] vmxnet3: add command to set ring buffer sizes

From: Ronak Doshi
Date: Wed Jun 08 2022 - 02:54:11 EST


This patch adds a new command to set ring buffer sizes. This is
required to pass the buffer size information to passthrough devices.
For performance reasons, with version7 and later, ring1 will contain
only mtu size buffers (bound to 3K). Packets > 3K will use both ring1
and ring2.

Also, ring sizes are round down to power of 2 and ring2 default
size is increased to 512.

Signed-off-by: Ronak Doshi <doshir@xxxxxxxxxx>
Acked-by: Guolin Yang <gyang@xxxxxxxxxx>
---
drivers/net/vmxnet3/vmxnet3_defs.h | 11 +++++++
drivers/net/vmxnet3/vmxnet3_drv.c | 57 +++++++++++++++++++++++++++--------
drivers/net/vmxnet3/vmxnet3_ethtool.c | 7 +++++
drivers/net/vmxnet3/vmxnet3_int.h | 3 +-
4 files changed, 65 insertions(+), 13 deletions(-)

diff --git a/drivers/net/vmxnet3/vmxnet3_defs.h b/drivers/net/vmxnet3/vmxnet3_defs.h
index 8d626611ab2d..415e4c9993ef 100644
--- a/drivers/net/vmxnet3/vmxnet3_defs.h
+++ b/drivers/net/vmxnet3/vmxnet3_defs.h
@@ -99,6 +99,9 @@ enum {
VMXNET3_CMD_SET_COALESCE,
VMXNET3_CMD_REGISTER_MEMREGS,
VMXNET3_CMD_SET_RSS_FIELDS,
+ VMXNET3_CMD_RESERVED4,
+ VMXNET3_CMD_RESERVED5,
+ VMXNET3_CMD_SET_RING_BUFFER_SIZE,

VMXNET3_CMD_FIRST_GET = 0xF00D0000,
VMXNET3_CMD_GET_QUEUE_STATUS = VMXNET3_CMD_FIRST_GET,
@@ -743,6 +746,13 @@ enum Vmxnet3_RSSField {
VMXNET3_RSS_FIELDS_ESPIP6 = 0x0020,
};

+struct Vmxnet3_RingBufferSize {
+ __le16 ring1BufSizeType0;
+ __le16 ring1BufSizeType1;
+ __le16 ring2BufSizeType1;
+ __le16 pad;
+};
+
/* If the command data <= 16 bytes, use the shared memory directly.
* otherwise, use variable length configuration descriptor.
*/
@@ -750,6 +760,7 @@ union Vmxnet3_CmdInfo {
struct Vmxnet3_VariableLenConfDesc varConf;
struct Vmxnet3_SetPolling setPolling;
enum Vmxnet3_RSSField setRssFields;
+ struct Vmxnet3_RingBufferSize ringBufSize;
__le64 data[2];
};

diff --git a/drivers/net/vmxnet3/vmxnet3_drv.c b/drivers/net/vmxnet3/vmxnet3_drv.c
index 94ca3bc1d540..c2f99c01a130 100644
--- a/drivers/net/vmxnet3/vmxnet3_drv.c
+++ b/drivers/net/vmxnet3/vmxnet3_drv.c
@@ -2681,6 +2681,23 @@ vmxnet3_setup_driver_shared(struct vmxnet3_adapter *adapter)
}

static void
+vmxnet3_init_bufsize(struct vmxnet3_adapter *adapter)
+{
+ struct Vmxnet3_DriverShared *shared = adapter->shared;
+ union Vmxnet3_CmdInfo *cmdInfo = &shared->cu.cmdInfo;
+ unsigned long flags;
+
+ if (!VMXNET3_VERSION_GE_7(adapter))
+ return;
+
+ cmdInfo->ringBufSize = adapter->ringBufSize;
+ spin_lock_irqsave(&adapter->cmd_lock, flags);
+ VMXNET3_WRITE_BAR1_REG(adapter, VMXNET3_REG_CMD,
+ VMXNET3_CMD_SET_RING_BUFFER_SIZE);
+ spin_unlock_irqrestore(&adapter->cmd_lock, flags);
+}
+
+static void
vmxnet3_init_coalesce(struct vmxnet3_adapter *adapter)
{
struct Vmxnet3_DriverShared *shared = adapter->shared;
@@ -2818,6 +2835,7 @@ vmxnet3_activate_dev(struct vmxnet3_adapter *adapter)
goto activate_err;
}

+ vmxnet3_init_bufsize(adapter);
vmxnet3_init_coalesce(adapter);
vmxnet3_init_rssfields(adapter);

@@ -2991,19 +3009,29 @@ static void
vmxnet3_adjust_rx_ring_size(struct vmxnet3_adapter *adapter)
{
size_t sz, i, ring0_size, ring1_size, comp_size;
- if (adapter->netdev->mtu <= VMXNET3_MAX_SKB_BUF_SIZE -
- VMXNET3_MAX_ETH_HDR_SIZE) {
- adapter->skb_buf_size = adapter->netdev->mtu +
- VMXNET3_MAX_ETH_HDR_SIZE;
- if (adapter->skb_buf_size < VMXNET3_MIN_T0_BUF_SIZE)
- adapter->skb_buf_size = VMXNET3_MIN_T0_BUF_SIZE;
-
- adapter->rx_buf_per_pkt = 1;
+ /* With version7 ring1 will have only T0 buffers */
+ if (!VMXNET3_VERSION_GE_7(adapter)) {
+ if (adapter->netdev->mtu <= VMXNET3_MAX_SKB_BUF_SIZE -
+ VMXNET3_MAX_ETH_HDR_SIZE) {
+ adapter->skb_buf_size = adapter->netdev->mtu +
+ VMXNET3_MAX_ETH_HDR_SIZE;
+ if (adapter->skb_buf_size < VMXNET3_MIN_T0_BUF_SIZE)
+ adapter->skb_buf_size = VMXNET3_MIN_T0_BUF_SIZE;
+
+ adapter->rx_buf_per_pkt = 1;
+ } else {
+ adapter->skb_buf_size = VMXNET3_MAX_SKB_BUF_SIZE;
+ sz = adapter->netdev->mtu - VMXNET3_MAX_SKB_BUF_SIZE +
+ VMXNET3_MAX_ETH_HDR_SIZE;
+ adapter->rx_buf_per_pkt = 1 + (sz + PAGE_SIZE - 1) / PAGE_SIZE;
+ }
} else {
- adapter->skb_buf_size = VMXNET3_MAX_SKB_BUF_SIZE;
- sz = adapter->netdev->mtu - VMXNET3_MAX_SKB_BUF_SIZE +
- VMXNET3_MAX_ETH_HDR_SIZE;
- adapter->rx_buf_per_pkt = 1 + (sz + PAGE_SIZE - 1) / PAGE_SIZE;
+ adapter->skb_buf_size = min((int)adapter->netdev->mtu + VMXNET3_MAX_ETH_HDR_SIZE,
+ VMXNET3_MAX_SKB_BUF_SIZE);
+ adapter->rx_buf_per_pkt = 1;
+ adapter->ringBufSize.ring1BufSizeType0 = cpu_to_le16(adapter->skb_buf_size);
+ adapter->ringBufSize.ring1BufSizeType1 = 0;
+ adapter->ringBufSize.ring2BufSizeType1 = cpu_to_le16(PAGE_SIZE);
}

/*
@@ -3019,6 +3047,11 @@ vmxnet3_adjust_rx_ring_size(struct vmxnet3_adapter *adapter)
ring1_size = (ring1_size + sz - 1) / sz * sz;
ring1_size = min_t(u32, ring1_size, VMXNET3_RX_RING2_MAX_SIZE /
sz * sz);
+ /* For v7 and later, keep ring size power of 2 for UPT */
+ if (VMXNET3_VERSION_GE_7(adapter)) {
+ ring0_size = rounddown_pow_of_two(ring0_size);
+ ring1_size = rounddown_pow_of_two(ring1_size);
+ }
comp_size = ring0_size + ring1_size;

for (i = 0; i < adapter->num_rx_queues; i++) {
diff --git a/drivers/net/vmxnet3/vmxnet3_ethtool.c b/drivers/net/vmxnet3/vmxnet3_ethtool.c
index 397b268f7bc5..ce3993282c0f 100644
--- a/drivers/net/vmxnet3/vmxnet3_ethtool.c
+++ b/drivers/net/vmxnet3/vmxnet3_ethtool.c
@@ -718,6 +718,13 @@ vmxnet3_set_ringparam(struct net_device *netdev,
new_rx_ring2_size = min_t(u32, new_rx_ring2_size,
VMXNET3_RX_RING2_MAX_SIZE);

+ /* For v7 and later, keep ring size power of 2 for UPT */
+ if (VMXNET3_VERSION_GE_7(adapter)) {
+ new_tx_ring_size = rounddown_pow_of_two(new_tx_ring_size);
+ new_rx_ring_size = rounddown_pow_of_two(new_rx_ring_size);
+ new_rx_ring2_size = rounddown_pow_of_two(new_rx_ring2_size);
+ }
+
/* rx data ring buffer size has to be a multiple of
* VMXNET3_RXDATA_DESC_SIZE_ALIGN
*/
diff --git a/drivers/net/vmxnet3/vmxnet3_int.h b/drivers/net/vmxnet3/vmxnet3_int.h
index 5b495ef253e8..cb87731f5f1c 100644
--- a/drivers/net/vmxnet3/vmxnet3_int.h
+++ b/drivers/net/vmxnet3/vmxnet3_int.h
@@ -408,6 +408,7 @@ struct vmxnet3_adapter {
dma_addr_t pm_conf_pa;
dma_addr_t rss_conf_pa;
bool queuesExtEnabled;
+ struct Vmxnet3_RingBufferSize ringBufSize;
u32 devcap_supported[8];
u32 ptcap_supported[8];
u32 dev_caps[8];
@@ -449,7 +450,7 @@ struct vmxnet3_adapter {
/* must be a multiple of VMXNET3_RING_SIZE_ALIGN */
#define VMXNET3_DEF_TX_RING_SIZE 512
#define VMXNET3_DEF_RX_RING_SIZE 1024
-#define VMXNET3_DEF_RX_RING2_SIZE 256
+#define VMXNET3_DEF_RX_RING2_SIZE 512

#define VMXNET3_DEF_RXDATA_DESC_SIZE 128

--
2.11.0