• Anjali Singhai Jain's avatar
    i40e/i40evf: Fix RS bit update in Tx path and disable force WB workaround · 6a7fded7
    Anjali Singhai Jain authored
    This patch fixes the issue of forcing WB too often causing us to not
    benefit from NAPI.
    
    Without this patch we were forcing WB/arming interrupt too often taking
    away the benefits of NAPI and causing a performance impact.
    
    With this patch we disable force WB in the clean routine for X710
    and XL710 adapters. X722 adapters do not enable interrupt to force
    a WB and benefit from WB_ON_ITR and hence force WB is left enabled
    for those adapters.
    For XL710 and X710 adapters if we have less than 4 packets pending
    a software Interrupt triggered from service task will force a WB.
    
    This patch also changes the conditions for setting RS bit as described
    in code comments. This optimizes when the HW does a tail bump amd when
    it does a WB. It also optimizes when we do a wmb.
    
    Change-ID: Id831e1ae7d3e2ec3f52cd0917b41ce1d22d75d9d
    Signed-off-by: default avatarAnjali Singhai Jain <anjali.singhai@intel.com>
    Tested-by: default avatarAndrew Bowers <andrewx.bowers@intel.com>
    Signed-off-by: default avatarJeff Kirsher <jeffrey.t.kirsher@intel.com>
    6a7fded7
i40e_txrx.c 56.3 KB