diff options
| author | Jeff Kirsher <jeffrey.t.kirsher@intel.com> | 2018-08-02 10:13:10 -0700 |
|---|---|---|
| committer | Jeff Kirsher <jeffrey.t.kirsher@intel.com> | 2018-12-20 11:02:06 -0800 |
| commit | 59361316afcb08569af21e1af83e89c7051c055a (patch) | |
| tree | a5c869635d88e80f836ca8b3f947d30e365fc25d /drivers/net/ethernet/intel/igb/igb_ethtool.c | |
| parent | 44a7b3b6e3a458f9549c2cc28e74ecdc470e42f1 (diff) | |
| download | linux-59361316afcb08569af21e1af83e89c7051c055a.tar.bz2 | |
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/intel/igb/igb_ethtool.c')
| -rw-r--r-- | drivers/net/ethernet/intel/igb/igb_ethtool.c | 4 |
1 files changed, 2 insertions, 2 deletions
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) |