From 827de39212298048e75309377c8262c4d7f2cb41 Mon Sep 17 00:00:00 2001 From: Jesse Brandeburg Date: Fri, 6 Nov 2015 15:26:07 -0800 Subject: [PATCH] i40e: use priv flags to control packet split Ethtool priv flags implementation to enable or disable packet split, which is a hardware feature that inspects headers and will put headers in a separate DMA buffer from the payload data. The driver was automatically choosing to enable packet split in some cases and this gives the user the ability to turn it off/on explicitly. to query state: ethtool --show-priv-flags ethx to enable: ethtool --set-priv-flags ethx packet-split on to disable: ethtool --set-priv-flags ethx packet-split off Why would anyone want this? Because some environments benefit from header/data split in the receive buffer, and the driver defaults to one or the other depending on environment/kernel parameters. Why didn't you implement a generic ethtool control for this feature? Because Intel hardware is the only hardware that supports header/data split. Change-ID: I803121e1eecc9ccb2884031fd85dd1110b3af66d Signed-off-by: Jesse Brandeburg Tested-by: Andrew Bowers Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/i40e/i40e.h | 1 + .../net/ethernet/intel/i40e/i40e_ethtool.c | 27 +++++++++++++++++++ 2 files changed, 28 insertions(+) diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h index dde7ae71bfb8..4ca85d554b52 100644 --- a/drivers/net/ethernet/intel/i40e/i40e.h +++ b/drivers/net/ethernet/intel/i40e/i40e.h @@ -104,6 +104,7 @@ #define I40E_PRIV_FLAGS_LINKPOLL_FLAG BIT(1) #define I40E_PRIV_FLAGS_FD_ATR BIT(2) #define I40E_PRIV_FLAGS_VEB_STATS BIT(3) +#define I40E_PRIV_FLAGS_PS BIT(4) #define I40E_NVM_VERSION_LO_SHIFT 0 #define I40E_NVM_VERSION_LO_MASK (0xff << I40E_NVM_VERSION_LO_SHIFT) diff --git a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c index b52c50924274..29d5833e24a3 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c +++ b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c @@ -231,6 +231,7 @@ static const char i40e_priv_flags_strings[][ETH_GSTRING_LEN] = { "LinkPolling", "flow-director-atr", "veb-stats", + "packet-split", }; #define I40E_PRIV_FLAGS_STR_LEN ARRAY_SIZE(i40e_priv_flags_strings) @@ -2709,6 +2710,8 @@ static u32 i40e_get_priv_flags(struct net_device *dev) I40E_PRIV_FLAGS_FD_ATR : 0; ret_flags |= pf->flags & I40E_FLAG_VEB_STATS_ENABLED ? I40E_PRIV_FLAGS_VEB_STATS : 0; + ret_flags |= pf->flags & I40E_FLAG_RX_PS_ENABLED ? + I40E_PRIV_FLAGS_PS : 0; return ret_flags; } @@ -2723,6 +2726,26 @@ static int i40e_set_priv_flags(struct net_device *dev, u32 flags) struct i40e_netdev_priv *np = netdev_priv(dev); struct i40e_vsi *vsi = np->vsi; struct i40e_pf *pf = vsi->back; + bool reset_required = false; + + /* NOTE: MFP is not settable */ + + /* allow the user to control the method of receive + * buffer DMA, whether the packet is split at header + * boundaries into two separate buffers. In some cases + * one routine or the other will perform better. + */ + if ((flags & I40E_PRIV_FLAGS_PS) && + !(pf->flags & I40E_FLAG_RX_PS_ENABLED)) { + pf->flags |= I40E_FLAG_RX_PS_ENABLED; + pf->flags &= ~I40E_FLAG_RX_1BUF_ENABLED; + reset_required = true; + } else if (!(flags & I40E_PRIV_FLAGS_PS) && + (pf->flags & I40E_FLAG_RX_PS_ENABLED)) { + pf->flags &= ~I40E_FLAG_RX_PS_ENABLED; + pf->flags |= I40E_FLAG_RX_1BUF_ENABLED; + reset_required = true; + } if (flags & I40E_PRIV_FLAGS_LINKPOLL_FLAG) pf->flags |= I40E_FLAG_LINK_POLLING_ENABLED; @@ -2745,6 +2768,10 @@ static int i40e_set_priv_flags(struct net_device *dev, u32 flags) else pf->flags &= ~I40E_FLAG_VEB_STATS_ENABLED; + /* if needed, issue reset to cause things to take effect */ + if (reset_required) + i40e_do_reset(pf, BIT(__I40E_PF_RESET_REQUESTED)); + return 0; } -- 2.30.2