Relaxed ordering is disabled by default at driver initialization
and re-enabled when DCA is used. The reason it is disabled was
due to an issue on some chipsets (see comments in ixgbe_update_tx_dca()).
But when DCA is not used, RO needs to be re-enabled, else we have
a serialization bottleneck on platforms like SPARC.
This patch eliminates the bottleneck for ixgbe when DCA is not configured.
Signed-off-by: Sowmini Varadhan <sowmini.varad...@oracle.com>
Cc: Emil Tantilov <emil.s.tanti...@intel.com>
---
v2: incoroporate comments from Emil Tantilov
drivers/net/ethernet/intel/ixgbe/ixgbe_82598.c | 23 +++++++++++++++++++++++
drivers/net/ethernet/intel/ixgbe/ixgbe_common.c | 20 ++++++++++++++++++++
drivers/net/ethernet/intel/ixgbe/ixgbe_common.h | 1 +
drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 11 +++++++++++
drivers/net/ethernet/intel/ixgbe/ixgbe_type.h | 1 +
drivers/net/ethernet/intel/ixgbe/ixgbe_x540.c | 1 +
6 files changed, 57 insertions(+), 0 deletions(-)
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_82598.c
b/drivers/net/ethernet/intel/ixgbe/ixgbe_82598.c
index c5c97b4..0c78b5a 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_82598.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_82598.c
@@ -1154,6 +1154,28 @@ static void ixgbe_set_rxpba_82598(struct ixgbe_hw *hw,
int num_pb,
IXGBE_WRITE_REG(hw, IXGBE_TXPBSIZE(i), IXGBE_TXPBSIZE_40KB);
}
+static void ixgbe_enable_relaxed_ordering_82598(struct ixgbe_hw *hw)
+{
+ u32 regval;
+ u32 i;
+
+ /* Enable relaxed ordering */
+ for (i = 0; ((i < hw->mac.max_tx_queues) &&
+ (i < IXGBE_DCA_MAX_QUEUES_82598)); i++) {
+ regval = IXGBE_READ_REG(hw, IXGBE_DCA_TXCTRL(i));
+ regval |= IXGBE_DCA_TXCTRL_DESC_WRO_EN;
+ IXGBE_WRITE_REG(hw, IXGBE_DCA_TXCTRL(i), regval);
+ }
+
+ for (i = 0; ((i < hw->mac.max_rx_queues) &&
+ (i < IXGBE_DCA_MAX_QUEUES_82598)); i++) {
+ regval = IXGBE_READ_REG(hw, IXGBE_DCA_RXCTRL(i));
+ regval |= IXGBE_DCA_RXCTRL_DATA_WRO_EN |
+ IXGBE_DCA_RXCTRL_HEAD_WRO_EN;
+ IXGBE_WRITE_REG(hw, IXGBE_DCA_RXCTRL(i), regval);
+ }
+}
+
static struct ixgbe_mac_operations mac_ops_82598 = {
.init_hw = &ixgbe_init_hw_generic,
.reset_hw = &ixgbe_reset_hw_82598,
@@ -1161,6 +1183,7 @@ static struct ixgbe_mac_operations mac_ops_82598 = {
.clear_hw_cntrs = &ixgbe_clear_hw_cntrs_generic,
.get_media_type = &ixgbe_get_media_type_82598,
.enable_rx_dma = &ixgbe_enable_rx_dma_generic,
+ .enable_relaxed_ordering = &ixgbe_enable_relaxed_ordering_82598,
.get_mac_addr = &ixgbe_get_mac_addr_generic,
.stop_adapter = &ixgbe_stop_adapter_generic,
.get_bus_info = &ixgbe_get_bus_info_generic,
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
index 9c66bab..4453d92 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
@@ -338,6 +338,26 @@ s32 ixgbe_start_hw_gen2(struct ixgbe_hw *hw)
return 0;
}
+void ixgbe_enable_relaxed_ordering(struct ixgbe_hw *hw)
+{
+ u32 i;
+ u32 regval;
+
+ /* Enable relaxed ordering */
+ for (i = 0; i < hw->mac.max_tx_queues; i++) {
+ regval = IXGBE_READ_REG(hw, IXGBE_DCA_TXCTRL_82599(i));
+ regval |= IXGBE_DCA_TXCTRL_DESC_WRO_EN;
+ IXGBE_WRITE_REG(hw, IXGBE_DCA_TXCTRL_82599(i), regval);
+ }
+
+ for (i = 0; i < hw->mac.max_rx_queues; i++) {
+ regval = IXGBE_READ_REG(hw, IXGBE_DCA_RXCTRL(i));
+ regval |= (IXGBE_DCA_RXCTRL_DATA_WRO_EN |
+ IXGBE_DCA_RXCTRL_HEAD_WRO_EN);
+ IXGBE_WRITE_REG(hw, IXGBE_DCA_RXCTRL(i), regval);
+ }
+}
+
/**
* ixgbe_init_hw_generic - Generic hardware initialization
* @hw: pointer to hardware structure
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.h
b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.h
index 8cfadcb..c399c18 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.h
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.h
@@ -37,6 +37,7 @@ s32 ixgbe_init_ops_generic(struct ixgbe_hw *hw);
s32 ixgbe_init_hw_generic(struct ixgbe_hw *hw);
s32 ixgbe_start_hw_generic(struct ixgbe_hw *hw);
s32 ixgbe_start_hw_gen2(struct ixgbe_hw *hw);
+void ixgbe_enable_relaxed_ordering(struct ixgbe_hw *hw);
s32 ixgbe_clear_hw_cntrs_generic(struct ixgbe_hw *hw);
s32 ixgbe_read_pba_string_generic(struct ixgbe_hw *hw, u8 *pba_num,
u32 pba_num_size);
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 2ed2c7d..dec815b 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -4898,6 +4898,12 @@ void ixgbe_reset(struct ixgbe_adapter *adapter)
if (test_bit(__IXGBE_PTP_RUNNING, &adapter->state))
ixgbe_ptp_reset(adapter);
+
+#ifndef CONFIG_IXGBE_DCA
+ /* ixgbe_update_tx_dca() will re-enable RO when DCA is enabled */
+ if (hw->mac.ops.enable_relaxed_ordering)
+ hw->mac.ops.enable_relaxed_ordering(hw);
+#endif
}
/**
@@ -8470,6 +8476,11 @@ skip_sriov:
"representative who provided you with this "
"hardware.\n");
}
+#ifndef CONFIG_IXGBE_DCA
+ /* ixgbe_update_tx_dca() will re-enable RO when DCA is enabled */
+ if (hw->mac.ops.enable_relaxed_ordering)
+ hw->mac.ops.enable_relaxed_ordering(hw);
+#endif
strcpy(netdev->name, "eth%d");
err = register_netdev(netdev);
if (err)
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
b/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
index d101b25..b967241 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
@@ -3013,6 +3013,7 @@ struct ixgbe_mac_operations {
void (*release_swfw_sync)(struct ixgbe_hw *, u32);
s32 (*prot_autoc_read)(struct ixgbe_hw *, bool *, u32 *);
s32 (*prot_autoc_write)(struct ixgbe_hw *, u32, bool);
+ void (*enable_relaxed_ordering)(struct ixgbe_hw *);
/* Link */
void (*disable_tx_laser)(struct ixgbe_hw *);
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_x540.c
b/drivers/net/ethernet/intel/ixgbe/ixgbe_x540.c
index ba54ff0..88adad2 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_x540.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_x540.c
@@ -781,6 +781,7 @@ static struct ixgbe_mac_operations mac_ops_X540 = {
.clear_hw_cntrs = &ixgbe_clear_hw_cntrs_generic,
.get_media_type = &ixgbe_get_media_type_X540,
.enable_rx_dma = &ixgbe_enable_rx_dma_generic,
+ .enable_relaxed_ordering = &ixgbe_enable_relaxed_ordering,
.get_mac_addr = &ixgbe_get_mac_addr_generic,
.get_san_mac_addr = &ixgbe_get_san_mac_addr_generic,
.get_device_caps = &ixgbe_get_device_caps_generic,
--
1.7.1
--
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