return failure ? budget : (int)total_rx_packets;
}
-static inline u32 i40e_buildreg_itr(const int type, u16 itr)
+/**
+ * i40e_buildreg_itr - build a value for writing to I40E_PFINT_DYN_CTLN register
+ * @itr_idx: interrupt throttling index
+ * @interval: interrupt throttling interval value in usecs
+ * @force_swint: force software interrupt
+ *
+ * The function builds a value for I40E_PFINT_DYN_CTLN register that
+ * is used to update interrupt throttling interval for specified ITR index
+ * and optionally enforces a software interrupt. If the @itr_idx is equal
+ * to I40E_ITR_NONE then no interval change is applied and only @force_swint
+ * parameter is taken into account. If the interval change and enforced
+ * software interrupt are not requested then the built value just enables
+ * appropriate vector interrupt.
+ **/
+static u32 i40e_buildreg_itr(enum i40e_dyn_idx itr_idx, u16 interval,
+ bool force_swint)
{
u32 val;
* an event in the PBA anyway so we need to rely on the automask
* to hold pending events for us until the interrupt is re-enabled
*
- * The itr value is reported in microseconds, and the register
- * value is recorded in 2 microsecond units. For this reason we
- * only need to shift by the interval shift - 1 instead of the
- * full value.
+ * We have to shift the given value as it is reported in microseconds
+ * and the register value is recorded in 2 microsecond units.
*/
- itr &= I40E_ITR_MASK;
+ interval >>= 1;
+ /* 1. Enable vector interrupt
+ * 2. Update the interval for the specified ITR index
+ * (I40E_ITR_NONE in the register is used to indicate that
+ * no interval update is requested)
+ */
val = I40E_PFINT_DYN_CTLN_INTENA_MASK |
- (type << I40E_PFINT_DYN_CTLN_ITR_INDX_SHIFT) |
- (itr << (I40E_PFINT_DYN_CTLN_INTERVAL_SHIFT - 1));
+ FIELD_PREP(I40E_PFINT_DYN_CTLN_ITR_INDX_MASK, itr_idx) |
+ FIELD_PREP(I40E_PFINT_DYN_CTLN_INTERVAL_MASK, interval);
+
+ /* 3. Enforce software interrupt trigger if requested
+ * (These software interrupts rate is limited by ITR2 that is
+ * set to 20K interrupts per second)
+ */
+ if (force_swint)
+ val |= I40E_PFINT_DYN_CTLN_SWINT_TRIG_MASK |
+ I40E_PFINT_DYN_CTLN_SW_ITR_INDX_ENA_MASK |
+ FIELD_PREP(I40E_PFINT_DYN_CTLN_SW_ITR_INDX_MASK,
+ I40E_SW_ITR);
return val;
}
-/* a small macro to shorten up some long lines */
-#define INTREG I40E_PFINT_DYN_CTLN
-
/* The act of updating the ITR will cause it to immediately trigger. In order
* to prevent this from throwing off adaptive update statistics we defer the
* update so that it can only happen so often. So after either Tx or Rx are
static inline void i40e_update_enable_itr(struct i40e_vsi *vsi,
struct i40e_q_vector *q_vector)
{
+ enum i40e_dyn_idx itr_idx = I40E_ITR_NONE;
struct i40e_hw *hw = &vsi->back->hw;
- u32 intval;
+ u16 interval = 0;
+ u32 itr_val;
/* If we don't have MSIX, then we only need to re-enable icr0 */
if (!test_bit(I40E_FLAG_MSIX_ENA, vsi->back->flags)) {
*/
if (q_vector->rx.target_itr < q_vector->rx.current_itr) {
/* Rx ITR needs to be reduced, this is highest priority */
- intval = i40e_buildreg_itr(I40E_RX_ITR,
- q_vector->rx.target_itr);
+ itr_idx = I40E_RX_ITR;
+ interval = q_vector->rx.target_itr;
q_vector->rx.current_itr = q_vector->rx.target_itr;
q_vector->itr_countdown = ITR_COUNTDOWN_START;
} else if ((q_vector->tx.target_itr < q_vector->tx.current_itr) ||
/* Tx ITR needs to be reduced, this is second priority
* Tx ITR needs to be increased more than Rx, fourth priority
*/
- intval = i40e_buildreg_itr(I40E_TX_ITR,
- q_vector->tx.target_itr);
+ itr_idx = I40E_TX_ITR;
+ interval = q_vector->tx.target_itr;
q_vector->tx.current_itr = q_vector->tx.target_itr;
q_vector->itr_countdown = ITR_COUNTDOWN_START;
} else if (q_vector->rx.current_itr != q_vector->rx.target_itr) {
/* Rx ITR needs to be increased, third priority */
- intval = i40e_buildreg_itr(I40E_RX_ITR,
- q_vector->rx.target_itr);
+ itr_idx = I40E_RX_ITR;
+ interval = q_vector->rx.target_itr;
q_vector->rx.current_itr = q_vector->rx.target_itr;
q_vector->itr_countdown = ITR_COUNTDOWN_START;
} else {
/* No ITR update, lowest priority */
- intval = i40e_buildreg_itr(I40E_ITR_NONE, 0);
if (q_vector->itr_countdown)
q_vector->itr_countdown--;
}
- if (!test_bit(__I40E_VSI_DOWN, vsi->state))
- wr32(hw, INTREG(q_vector->reg_idx), intval);
+ /* Do not update interrupt control register if VSI is down */
+ if (test_bit(__I40E_VSI_DOWN, vsi->state))
+ return;
+
+ /* Update ITR interval if necessary and enforce software interrupt
+ * if we are exiting busy poll.
+ */
+ if (q_vector->in_busy_poll) {
+ itr_val = i40e_buildreg_itr(itr_idx, interval, true);
+ q_vector->in_busy_poll = false;
+ } else {
+ itr_val = i40e_buildreg_itr(itr_idx, interval, false);
+ }
+ wr32(hw, I40E_PFINT_DYN_CTLN(q_vector->reg_idx), itr_val);
}
/**
*/
if (likely(napi_complete_done(napi, work_done)))
i40e_update_enable_itr(vsi, q_vector);
+ else
+ q_vector->in_busy_poll = true;
return min(work_done, budget - 1);
}
git.samba.org / sfrench / cifs-2.6.git / commitdiff