bnx2x: Create workqueue for IOV related tasks

The bnx2x sriov mechanisms were done in the bnx2x slowpath workitem which
runs on the bnx2x's workqueue; This workitem is also responsible for the bottom
half of interrupt handling in the driver, and specifically it also receives
FW notifications of ramrod completions, allowing other flows to progress.

The original design of the sriov reltaed-flows was based on the notion such
flows must not sleep, since their context is the slowpath workitem.
Otherwise, we might reach timeouts - those flows may wait for ramrod completion
that will never arrive as the workitem wlll not be re-scheduled until that same
flow will be over.

In more recent time bnx2x started supporting features in which the VF interface
can be configured by the tools accessing the PF on the hypervisor.
This support created possible races on the VF-PF lock (which is taken either
when the PF is handling a VF message or when the PF is doing some slowpath work
on behalf of the VF) which may cause timeouts on the VF side and lags on the PF
side.

This patch changes the scheme - it creates a new workqueue for sriov related
tasks and moves all handling currently done in the slowpath task into the the
new workqueue.

Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: Ariel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 60 insertions, 43 deletions

diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c
index 1117ed7776b6..63c95658ba60 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_vfpf.c
@@ -1089,9 +1089,6 @@ static void bnx2x_vf_mbx_resp_send_msg(struct bnx2x *bp,
 	storm_memset_vf_mbx_ack(bp, vf->abs_vfid);
 	mmiowb();
 
-	/* initiate dmae to send the response */
-	mbx->flags &= ~VF_MSG_INPROCESS;
-
 	/* copy the response header including status-done field,
 	 * must be last dmae, must be after FW is acked
 	 */
@@ -2059,13 +2056,10 @@ static void bnx2x_vf_mbx_request(struct bnx2x *bp, struct bnx2x_virtf *vf,
 	}
 }
 
-/* handle new vf-pf message */
-void bnx2x_vf_mbx(struct bnx2x *bp, struct vf_pf_event_data *vfpf_event)
+void bnx2x_vf_mbx_schedule(struct bnx2x *bp,
+			   struct vf_pf_event_data *vfpf_event)
 {
-	struct bnx2x_virtf *vf;
-	struct bnx2x_vf_mbx *mbx;
 	u8 vf_idx;
-	int rc;
 
 	DP(BNX2X_MSG_IOV,
 	   "vf pf event received: vfid %d, address_hi %x, address lo %x",
@@ -2077,50 +2071,73 @@ void bnx2x_vf_mbx(struct bnx2x *bp, struct vf_pf_event_data *vfpf_event)
 	    BNX2X_NR_VIRTFN(bp)) {
 		BNX2X_ERR("Illegal vf_id %d max allowed: %d\n",
 			  vfpf_event->vf_id, BNX2X_NR_VIRTFN(bp));
-		goto mbx_done;
+		return;
 	}
+
 	vf_idx = bnx2x_vf_idx_by_abs_fid(bp, vfpf_event->vf_id);
-	mbx = BP_VF_MBX(bp, vf_idx);
 
-	/* verify an event is not currently being processed -
-	 * debug failsafe only
-	 */
-	if (mbx->flags & VF_MSG_INPROCESS) {
-		BNX2X_ERR("Previous message is still being processed, vf_id %d\n",
-			  vfpf_event->vf_id);
-		goto mbx_done;
-	}
-	vf = BP_VF(bp, vf_idx);
+	/* Update VFDB with current message and schedule its handling */
+	mutex_lock(&BP_VFDB(bp)->event_mutex);
+	BP_VF_MBX(bp, vf_idx)->vf_addr_hi = vfpf_event->msg_addr_hi;
+	BP_VF_MBX(bp, vf_idx)->vf_addr_lo = vfpf_event->msg_addr_lo;
+	BP_VFDB(bp)->event_occur |= (1ULL << vf_idx);
+	mutex_unlock(&BP_VFDB(bp)->event_mutex);
 
-	/* save the VF message address */
-	mbx->vf_addr_hi = vfpf_event->msg_addr_hi;
-	mbx->vf_addr_lo = vfpf_event->msg_addr_lo;
-	DP(BNX2X_MSG_IOV, "mailbox vf address hi 0x%x, lo 0x%x, offset 0x%x\n",
-	   mbx->vf_addr_hi, mbx->vf_addr_lo, mbx->first_tlv.resp_msg_offset);
+	bnx2x_schedule_iov_task(bp, BNX2X_IOV_HANDLE_VF_MSG);
+}
 
-	/* dmae to get the VF request */
-	rc = bnx2x_copy32_vf_dmae(bp, true, mbx->msg_mapping, vf->abs_vfid,
-				  mbx->vf_addr_hi, mbx->vf_addr_lo,
-				  sizeof(union vfpf_tlvs)/4);
-	if (rc) {
-		BNX2X_ERR("Failed to copy request VF %d\n", vf->abs_vfid);
-		goto mbx_error;
-	}
+/* handle new vf-pf messages */
+void bnx2x_vf_mbx(struct bnx2x *bp)
+{
+	struct bnx2x_vfdb *vfdb = BP_VFDB(bp);
+	u64 events;
+	u8 vf_idx;
+	int rc;
 
-	/* process the VF message header */
-	mbx->first_tlv = mbx->msg->req.first_tlv;
+	if (!vfdb)
+		return;
 
-	/* Clean response buffer to refrain from falsely seeing chains */
-	memset(&mbx->msg->resp, 0, sizeof(union pfvf_tlvs));
+	mutex_lock(&vfdb->event_mutex);
+	events = vfdb->event_occur;
+	vfdb->event_occur = 0;
+	mutex_unlock(&vfdb->event_mutex);
 
-	/* dispatch the request (will prepare the response) */
-	bnx2x_vf_mbx_request(bp, vf, mbx);
-	goto mbx_done;
+	for_each_vf(bp, vf_idx) {
+		struct bnx2x_vf_mbx *mbx = BP_VF_MBX(bp, vf_idx);
+		struct bnx2x_virtf *vf = BP_VF(bp, vf_idx);
 
-mbx_error:
-	bnx2x_vf_release(bp, vf, false); /* non blocking */
-mbx_done:
-	return;
+		/* Handle VFs which have pending events */
+		if (!(events & (1ULL << vf_idx)))
+			continue;
+
+		DP(BNX2X_MSG_IOV,
+		   "Handling vf pf event vfid %d, address: [%x:%x], resp_offset 0x%x\n",
+		   vf_idx, mbx->vf_addr_hi, mbx->vf_addr_lo,
+		   mbx->first_tlv.resp_msg_offset);
+
+		/* dmae to get the VF request */
+		rc = bnx2x_copy32_vf_dmae(bp, true, mbx->msg_mapping,
+					  vf->abs_vfid, mbx->vf_addr_hi,
+					  mbx->vf_addr_lo,
+					  sizeof(union vfpf_tlvs)/4);
+		if (rc) {
+			BNX2X_ERR("Failed to copy request VF %d\n",
+				  vf->abs_vfid);
+			bnx2x_vf_release(bp, vf, false); /* non blocking */
+			return;
+		}
+
+		/* process the VF message header */
+		mbx->first_tlv = mbx->msg->req.first_tlv;
+
+		/* Clean response buffer to refrain from falsely
+		 * seeing chains.
+		 */
+		memset(&mbx->msg->resp, 0, sizeof(union pfvf_tlvs));
+
+		/* dispatch the request (will prepare the response) */
+		bnx2x_vf_mbx_request(bp, vf, mbx);
+	}
 }
 
 /* propagate local bulletin board to vf */