ice: manage interrupts during poll exit

The driver would occasionally miss that there were outstanding
descriptors to clean when exiting busy/napi poll. This issue has
been in the code since the introduction of the ice driver.

Attempt to "catch" any remaining work by triggering a software
interrupt when exiting napi poll or busy-poll. This will not
cause extra interrupts in the case of normal execution.

This issue was found when running sfnt-pingpong, with busy
poll enabled, and typically with larger I/O sizes like > 8192,
the program would occasionally report > 1 second maximums
to complete a ping pong.

Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Tony Brelinski <tonyx.brelinski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
This commit is contained in:
Jesse Brandeburg 2021-03-31 14:16:58 -07:00 committed by Tony Nguyen
parent cdf1f1f169
commit b7306b42be
2 changed files with 13 additions and 1 deletions

View file

@ -130,6 +130,7 @@
#define GLINT_DYN_CTL_ITR_INDX_M ICE_M(0x3, 3)
#define GLINT_DYN_CTL_INTERVAL_S 5
#define GLINT_DYN_CTL_INTERVAL_M ICE_M(0xFFF, 5)
#define GLINT_DYN_CTL_SW_ITR_INDX_ENA_M BIT(24)
#define GLINT_DYN_CTL_SW_ITR_INDX_M ICE_M(0x3, 25)
#define GLINT_DYN_CTL_WB_ON_ITR_M BIT(30)
#define GLINT_DYN_CTL_INTENA_MSK_M BIT(31)

View file

@ -1302,6 +1302,7 @@ static u32 ice_buildreg_itr(u16 itr_idx, u16 itr)
static void ice_update_ena_itr(struct ice_q_vector *q_vector)
{
struct ice_vsi *vsi = q_vector->vsi;
bool wb_en = q_vector->wb_on_itr;
u32 itr_val;
if (test_bit(ICE_DOWN, vsi->state))
@ -1310,7 +1311,7 @@ static void ice_update_ena_itr(struct ice_q_vector *q_vector)
/* When exiting WB_ON_ITR, let ITR resume its normal
* interrupts-enabled path.
*/
if (q_vector->wb_on_itr)
if (wb_en)
q_vector->wb_on_itr = false;
/* This will do nothing if dynamic updates are not enabled. */
@ -1318,6 +1319,16 @@ static void ice_update_ena_itr(struct ice_q_vector *q_vector)
/* net_dim() updates ITR out-of-band using a work item */
itr_val = ice_buildreg_itr(ICE_ITR_NONE, 0);
/* trigger an immediate software interrupt when exiting
* busy poll, to make sure to catch any pending cleanups
* that might have been missed due to interrupt state
* transition.
*/
if (wb_en) {
itr_val |= GLINT_DYN_CTL_SWINT_TRIG_M |
GLINT_DYN_CTL_SW_ITR_INDX_M |
GLINT_DYN_CTL_SW_ITR_INDX_ENA_M;
}
wr32(&vsi->back->hw, GLINT_DYN_CTL(q_vector->reg_idx), itr_val);
}