diff options
| author | Jeff Kirsher | 2018-08-02 10:13:10 -0700 |
|---|---|---|
| committer | Jeff Kirsher | 2018-12-20 11:02:06 -0800 |
| commit | 59361316afcb08569af21e1af83e89c7051c055a (patch) | |
| tree | a5c869635d88e80f836ca8b3f947d30e365fc25d /drivers/net/ethernet | |
| parent | 44a7b3b6e3a458f9549c2cc28e74ecdc470e42f1 (diff) | |
igb: reduce CPU0 latency when updating statistics
This change is based off of the work and suggestion of Jan Jablonsky
<jan.jablonsky@thalesgroup.com>.
The Watchdog workqueue in igb driver is scheduled every 2s for each
network interface. That includes updating a statistics protected by
spinlock. Function igb_update_stats in this case will be protected
against preemption. According to number of a statistics registers
(cca 60), processing this function might cause additional cpu load
on CPU0.
In case of statistics spinlock may be replaced with mutex, which
reduce latency on CPU0.
CC: Bernhard Kaindl <bernhard.kaindl@thalesgroup.com>
CC: Jan Jablonsky <jan.jablonsky@thalesgroup.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Diffstat (limited to 'drivers/net/ethernet')
| -rw-r--r-- | drivers/net/ethernet/intel/igb/igb.h | 2 | ||||
| -rw-r--r-- | drivers/net/ethernet/intel/igb/igb_ethtool.c | 4 | ||||
| -rw-r--r-- | drivers/net/ethernet/intel/igb/igb_main.c | 14 |
3 files changed, 10 insertions, 10 deletions
diff --git a/drivers/net/ethernet/intel/igb/igb.h b/drivers/net/ethernet/intel/igb/igb.h index ca54e268d157..fe1592ae8769 100644 --- a/drivers/net/ethernet/intel/igb/igb.h +++ b/drivers/net/ethernet/intel/igb/igb.h @@ -515,7 +515,7 @@ struct igb_adapter { /* OS defined structs */ struct pci_dev *pdev; - spinlock_t stats64_lock; + struct mutex stats64_lock; struct rtnl_link_stats64 stats64; /* structs defined in e1000_hw.h */ diff --git a/drivers/net/ethernet/intel/igb/igb_ethtool.c b/drivers/net/ethernet/intel/igb/igb_ethtool.c index c57671068245..7426060b678f 100644 --- a/drivers/net/ethernet/intel/igb/igb_ethtool.c +++ b/drivers/net/ethernet/intel/igb/igb_ethtool.c @@ -2295,7 +2295,7 @@ static void igb_get_ethtool_stats(struct net_device *netdev, int i, j; char *p; - spin_lock(&adapter->stats64_lock); + mutex_lock(&adapter->stats64_lock); igb_update_stats(adapter); for (i = 0; i < IGB_GLOBAL_STATS_LEN; i++) { @@ -2338,7 +2338,7 @@ static void igb_get_ethtool_stats(struct net_device *netdev, } while (u64_stats_fetch_retry_irq(&ring->rx_syncp, start)); i += IGB_RX_QUEUE_STATS_LEN; } - spin_unlock(&adapter->stats64_lock); + mutex_unlock(&adapter->stats64_lock); } static void igb_get_strings(struct net_device *netdev, u32 stringset, u8 *data) diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c index 453ae1d9e5f3..bb4f3f64fbf0 100644 --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -2203,9 +2203,9 @@ void igb_down(struct igb_adapter *adapter) del_timer_sync(&adapter->phy_info_timer); /* record the stats before reset*/ - spin_lock(&adapter->stats64_lock); + mutex_lock(&adapter->stats64_lock); igb_update_stats(adapter); - spin_unlock(&adapter->stats64_lock); + mutex_unlock(&adapter->stats64_lock); adapter->link_speed = 0; adapter->link_duplex = 0; @@ -3840,7 +3840,7 @@ static int igb_sw_init(struct igb_adapter *adapter) adapter->min_frame_size = ETH_ZLEN + ETH_FCS_LEN; spin_lock_init(&adapter->nfc_lock); - spin_lock_init(&adapter->stats64_lock); + mutex_init(&adapter->stats64_lock); #ifdef CONFIG_PCI_IOV switch (hw->mac.type) { case e1000_82576: @@ -5406,9 +5406,9 @@ no_wait: } } - spin_lock(&adapter->stats64_lock); + mutex_lock(&adapter->stats64_lock); igb_update_stats(adapter); - spin_unlock(&adapter->stats64_lock); + mutex_unlock(&adapter->stats64_lock); for (i = 0; i < adapter->num_tx_queues; i++) { struct igb_ring *tx_ring = adapter->tx_ring[i]; @@ -6235,10 +6235,10 @@ static void igb_get_stats64(struct net_device *netdev, { struct igb_adapter *adapter = netdev_priv(netdev); - spin_lock(&adapter->stats64_lock); + mutex_lock(&adapter->stats64_lock); igb_update_stats(adapter); memcpy(stats, &adapter->stats64, sizeof(*stats)); - spin_unlock(&adapter->stats64_lock); + mutex_unlock(&adapter->stats64_lock); } /** |