| Message ID | 20231127233350.2652604-1-jacob.e.keller@intel.com |
|---|---|
| State | Accepted |
| Delegated to: | Anthony Nguyen |
| Headers | show |
| Series | [iwl-net,v2] iavf: validate tx_coalesce_usecs even if rx_coalesce_usecs is zero | expand |
> -----Original Message----- > From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf Of > Jacob Keller > Sent: Tuesday, November 28, 2023 12:34 AM > To: Intel Wired LAN <intel-wired-lan@lists.osuosl.org> > Cc: Keller, Jacob E <jacob.e.keller@intel.com>; Kitszel, Przemyslaw > <przemyslaw.kitszel@intel.com>; Nguyen, Anthony L > <anthony.l.nguyen@intel.com> > Subject: [Intel-wired-lan] [PATCH iwl-net v2] iavf: validate tx_coalesce_usecs > even if rx_coalesce_usecs is zero > > In __iavf_set_coalesce, the driver checks both ec->rx_coalesce_usecs and > ec->tx_coalesce_usecs for validity. It does this via a chain if > ec->if/else-if > blocks. If every single branch of the series of if statements exited, this would > be fine. However, the rx_coalesce_usecs is checked against zero to print an > informative message if use_adaptive_rx_coalesce is enabled. If this check is > true, it short circuits the entire chain of statements, preventing validation of > the tx_coalesce_usecs field. > > Indeed, since commit e792779e6b63 ("iavf: Prevent changing static ITR values > if adaptive moderation is on") the iavf driver actually rejects any change to the > tx_coalesce_usecs or rx_coalesce_usecs when use_adaptive_tx_coalesce or > use_adaptive_rx_coalesce is enabled, making this checking a bit redundant. > > Fix this error by removing the unnecessary and redundant checks for > use_adaptive_rx_coalesce and use_adaptive_tx_coalesce. Since zero is a valid > value, and since the tx_coalesce_usecs and rx_coalesce_usecs fields are already > unsigned, remove the minimum value check. This allows assigning an ITR value > ranging from 0-8160 as described by the printed message. > > Fixes: 65e87c0398f5 ("i40evf: support queue-specific settings for interrupt > moderation") > Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> > --- > > Changes since v1: > * Fix the new check to continue allowing zero as a valid ITR value > > drivers/net/ethernet/intel/iavf/iavf_ethtool.c | 12 ++---------- > drivers/net/ethernet/intel/iavf/iavf_txrx.h | 1 - > 2 files changed, 2 insertions(+), 11 deletions(-) > > diff --git a/drivers/net/ethernet/intel/iavf/iavf_ethtool.c > b/drivers/net/ethernet/intel/iavf/iavf_ethtool.c > index 6f236d1a6444..19cbfe554689 100644 > --- a/drivers/net/ethernet/intel/iavf/iavf_ethtool.c > +++ b/drivers/net/ethernet/intel/iavf/iavf_ethtool.c Tested-by: Rafal Romanowski <rafal.romanowski@intel.com>
diff --git a/drivers/net/ethernet/intel/iavf/iavf_ethtool.c b/drivers/net/ethernet/intel/iavf/iavf_ethtool.c index 6f236d1a6444..19cbfe554689 100644 --- a/drivers/net/ethernet/intel/iavf/iavf_ethtool.c +++ b/drivers/net/ethernet/intel/iavf/iavf_ethtool.c @@ -827,18 +827,10 @@ static int __iavf_set_coalesce(struct net_device *netdev, struct iavf_adapter *adapter = netdev_priv(netdev); int i; - if (ec->rx_coalesce_usecs == 0) { - if (ec->use_adaptive_rx_coalesce) - netif_info(adapter, drv, netdev, "rx-usecs=0, need to disable adaptive-rx for a complete disable\n"); - } else if ((ec->rx_coalesce_usecs < IAVF_MIN_ITR) || - (ec->rx_coalesce_usecs > IAVF_MAX_ITR)) { + if (ec->rx_coalesce_usecs > IAVF_MAX_ITR) { netif_info(adapter, drv, netdev, "Invalid value, rx-usecs range is 0-8160\n"); return -EINVAL; - } else if (ec->tx_coalesce_usecs == 0) { - if (ec->use_adaptive_tx_coalesce) - netif_info(adapter, drv, netdev, "tx-usecs=0, need to disable adaptive-tx for a complete disable\n"); - } else if ((ec->tx_coalesce_usecs < IAVF_MIN_ITR) || - (ec->tx_coalesce_usecs > IAVF_MAX_ITR)) { + } else if (ec->tx_coalesce_usecs > IAVF_MAX_ITR) { netif_info(adapter, drv, netdev, "Invalid value, tx-usecs range is 0-8160\n"); return -EINVAL; } diff --git a/drivers/net/ethernet/intel/iavf/iavf_txrx.h b/drivers/net/ethernet/intel/iavf/iavf_txrx.h index 7e6ee32d19b6..10ba36602c0c 100644 --- a/drivers/net/ethernet/intel/iavf/iavf_txrx.h +++ b/drivers/net/ethernet/intel/iavf/iavf_txrx.h @@ -15,7 +15,6 @@ */ #define IAVF_ITR_DYNAMIC 0x8000 /* use top bit as a flag */ #define IAVF_ITR_MASK 0x1FFE /* mask for ITR register value */ -#define IAVF_MIN_ITR 2 /* reg uses 2 usec resolution */ #define IAVF_ITR_100K 10 /* all values below must be even */ #define IAVF_ITR_50K 20 #define IAVF_ITR_20K 50
In __iavf_set_coalesce, the driver checks both ec->rx_coalesce_usecs and ec->tx_coalesce_usecs for validity. It does this via a chain if if/else-if blocks. If every single branch of the series of if statements exited, this would be fine. However, the rx_coalesce_usecs is checked against zero to print an informative message if use_adaptive_rx_coalesce is enabled. If this check is true, it short circuits the entire chain of statements, preventing validation of the tx_coalesce_usecs field. Indeed, since commit e792779e6b63 ("iavf: Prevent changing static ITR values if adaptive moderation is on") the iavf driver actually rejects any change to the tx_coalesce_usecs or rx_coalesce_usecs when use_adaptive_tx_coalesce or use_adaptive_rx_coalesce is enabled, making this checking a bit redundant. Fix this error by removing the unnecessary and redundant checks for use_adaptive_rx_coalesce and use_adaptive_tx_coalesce. Since zero is a valid value, and since the tx_coalesce_usecs and rx_coalesce_usecs fields are already unsigned, remove the minimum value check. This allows assigning an ITR value ranging from 0-8160 as described by the printed message. Fixes: 65e87c0398f5 ("i40evf: support queue-specific settings for interrupt moderation") Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> --- Changes since v1: * Fix the new check to continue allowing zero as a valid ITR value drivers/net/ethernet/intel/iavf/iavf_ethtool.c | 12 ++---------- drivers/net/ethernet/intel/iavf/iavf_txrx.h | 1 - 2 files changed, 2 insertions(+), 11 deletions(-) base-commit: 218db91044f8f2f6db95ff4788ac1a03fcaf7c4a prerequisite-patch-id: b6de8a16db743e14af55f1b9cf67f31ef4da0900 prerequisite-patch-id: d36ab3205e29262f859cbecc76f6f52aa35dd1b5 prerequisite-patch-id: 0d1bf2d99824f1a2090539ef5bdd4ea96fbd9957