leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

ice: Set WB_ON_ITR when we don't re-enable interrupts

Browse Source 
Currently when busy polling is enabled we aren't setting/enabling
WB_ON_ITR in the driver. This doesn't break the driver, but it does
cause issues. If we don't enable WB_ON_ITR mode we will still get
write-backs from hardware during polling when a cache line has been
filled, but if a cache line is not filled we will not get the
write-back because WB_ON_ITR is not set. Fix this by enabling
WB_ON_ITR in the driver when interrupts are disabled.

Signed-off-by: Brett Creeley <brett.creeley@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This commit is contained in:
Brett Creeley
2019-07-25 01:55:32 -07:00
committed by Jeff Kirsher
parent f1a4a66d23
commit 2ab28bb04c
3 changed files with 70 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

54
drivers/net/ethernet/intel/ice/ice_txrx.c
View File

@@ -1355,6 +1355,23 @@ ice_update_ena_itr(struct ice_vsi *vsi, struct ice_q_vector *q_vector)
struct ice_ring_container *rx = &q_vector->rx;
u32 itr_val;
/* when exiting WB_ON_ITR lets set a low ITR value and trigger
* interrupts to expire right away in case we have more work ready to go
* already
*/
if (q_vector->itr_countdown == ICE_IN_WB_ON_ITR_MODE) {
itr_val = ice_buildreg_itr(rx->itr_idx, ICE_WB_ON_ITR_USECS);
wr32(&vsi->back->hw, GLINT_DYN_CTL(q_vector->reg_idx), itr_val);
/* set target back to last user set value */
rx->target_itr = rx->itr_setting;
/* set current to what we just wrote and dynamic if needed */
rx->current_itr = ICE_WB_ON_ITR_USECS |
(rx->itr_setting & ICE_ITR_DYNAMIC);
/* allow normal interrupt flow to start */
q_vector->itr_countdown = 0;
return;
}
/* This will do nothing if dynamic updates are not enabled */
ice_update_itr(q_vector, tx);
ice_update_itr(q_vector, rx);
@@ -1399,6 +1416,41 @@ ice_update_ena_itr(struct ice_vsi *vsi, struct ice_q_vector *q_vector)
itr_val);
}
/**
* ice_set_wb_on_itr - set WB_ON_ITR for this q_vector
* @vsi: pointer to the VSI structure
* @q_vector: q_vector to set WB_ON_ITR on
*
* We need to tell hardware to write-back completed descriptors even when
* interrupts are disabled. Descriptors will be written back on cache line
* boundaries without WB_ON_ITR enabled, but if we don't enable WB_ON_ITR
* descriptors may not be written back if they don't fill a cache line until the
* next interrupt.
*
* This sets the write-back frequency to 2 microseconds as that is the minimum
* value that's not 0 due to ITR granularity. Also, set the INTENA_MSK bit to
* make sure hardware knows we aren't meddling with the INTENA_M bit.
*/
static void
ice_set_wb_on_itr(struct ice_vsi *vsi, struct ice_q_vector *q_vector)
{
/* already in WB_ON_ITR mode no need to change it */
if (q_vector->itr_countdown == ICE_IN_WB_ON_ITR_MODE)
return;
if (q_vector->num_ring_rx)
wr32(&vsi->back->hw, GLINT_DYN_CTL(q_vector->reg_idx),
ICE_GLINT_DYN_CTL_WB_ON_ITR(ICE_WB_ON_ITR_USECS,
ICE_RX_ITR));
if (q_vector->num_ring_tx)
wr32(&vsi->back->hw, GLINT_DYN_CTL(q_vector->reg_idx),
ICE_GLINT_DYN_CTL_WB_ON_ITR(ICE_WB_ON_ITR_USECS,
ICE_TX_ITR));
q_vector->itr_countdown = ICE_IN_WB_ON_ITR_MODE;
}
/**
* ice_napi_poll - NAPI polling Rx/Tx cleanup routine
* @napi: napi struct with our devices info in it
@@ -1459,6 +1511,8 @@ int ice_napi_poll(struct napi_struct *napi, int budget)
*/
if (likely(napi_complete_done(napi, work_done)))
ice_update_ena_itr(vsi, q_vector);
else
ice_set_wb_on_itr(vsi, q_vector);
return min_t(int, work_done, budget - 1);
}