From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tony Nguyen Date: Wed, 31 Mar 2021 14:16:58 -0700 Subject: [Intel-wired-lan] [PATCH S58 03/13] ice: manage interrupts during poll exit In-Reply-To: <20210331211708.55205-1-anthony.l.nguyen@intel.com> References: <20210331211708.55205-1-anthony.l.nguyen@intel.com> Message-ID: <20210331211708.55205-3-anthony.l.nguyen@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: intel-wired-lan@osuosl.org List-ID: From: Jesse Brandeburg 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 Signed-off-by: Tony Nguyen --- drivers/net/ethernet/intel/ice/ice_hw_autogen.h | 1 + drivers/net/ethernet/intel/ice/ice_txrx.c | 13 ++++++++++++- 2 files changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/intel/ice/ice_hw_autogen.h b/drivers/net/ethernet/intel/ice/ice_hw_autogen.h index a501e2b7e09e..9b8300d4a267 100644 --- a/drivers/net/ethernet/intel/ice/ice_hw_autogen.h +++ b/drivers/net/ethernet/intel/ice/ice_hw_autogen.h @@ -131,6 +131,7 @@ #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) diff --git a/drivers/net/ethernet/intel/ice/ice_txrx.c b/drivers/net/ethernet/intel/ice/ice_txrx.c index 035fac5f74dc..ac22457f3bf8 100644 --- a/drivers/net/ethernet/intel/ice/ice_txrx.c +++ b/drivers/net/ethernet/intel/ice/ice_txrx.c @@ -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); } -- 2.20.1