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From: Dennis Dalessandro <dennis.dalessandro@intel.com>
To: jgg@ziepe.ca, dledford@redhat.com
Cc: Mike Marciniszyn <mike.marciniszyn@intel.com>,
	Grzegorz Andrejczuk <grzegorz.andrejczuk@intel.com>,
	Dennis Dalessandro <dennis.alessandro@intel.com>,
	linux-rdma@vger.kernel.org, Kaike Wan <kaike.wan@intel.com>,
	Sadanand Warrier <sadanand.warrier@intel.com>
Subject: [PATCH for-next 10/16] IB/hfi1: Add interrupt handler functions for accelerated ipoib
Date: Mon, 10 Feb 2020 08:19:09 -0500	[thread overview]
Message-ID: <20200210131909.87776.95106.stgit@awfm-01.aw.intel.com> (raw)
In-Reply-To: <20200210131223.87776.21339.stgit@awfm-01.aw.intel.com>

From: Grzegorz Andrejczuk <grzegorz.andrejczuk@intel.com>

This patch adds the interrupt handler function, the NAPI poll
function, and its associated helper functions for receiving
accelerated ipoib packets. While we are here, fix the formats
of two error printouts.

Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: Dennis Dalessandro <dennis.alessandro@intel.com>
Signed-off-by: Sadanand Warrier <sadanand.warrier@intel.com>
Signed-off-by: Grzegorz Andrejczuk <grzegorz.andrejczuk@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
---
 drivers/infiniband/hw/hfi1/affinity.c |   12 +++
 drivers/infiniband/hw/hfi1/affinity.h |    3 +
 drivers/infiniband/hw/hfi1/chip.c     |   44 ++++++++++++
 drivers/infiniband/hw/hfi1/chip.h     |    1 
 drivers/infiniband/hw/hfi1/driver.c   |  120 +++++++++++++++++++++++++++++++++
 drivers/infiniband/hw/hfi1/hfi.h      |    4 +
 drivers/infiniband/hw/hfi1/init.c     |    1 
 drivers/infiniband/hw/hfi1/msix.c     |   20 +++++-
 drivers/infiniband/hw/hfi1/msix.h     |    5 +
 drivers/infiniband/hw/hfi1/netdev.h   |    3 +
 10 files changed, 206 insertions(+), 7 deletions(-)

diff --git a/drivers/infiniband/hw/hfi1/affinity.c b/drivers/infiniband/hw/hfi1/affinity.c
index c142b23..d24b084 100644
--- a/drivers/infiniband/hw/hfi1/affinity.c
+++ b/drivers/infiniband/hw/hfi1/affinity.c
@@ -1,5 +1,5 @@
 /*
- * Copyright(c) 2015 - 2018 Intel Corporation.
+ * Copyright(c) 2015 - 2020 Intel Corporation.
  *
  * This file is provided under a dual BSD/GPLv2 license.  When using or
  * redistributing this file, you may do so under either license.
@@ -64,6 +64,7 @@ struct hfi1_affinity_node_list node_affinity = {
 static const char * const irq_type_names[] = {
 	"SDMA",
 	"RCVCTXT",
+	"NETDEVCTXT",
 	"GENERAL",
 	"OTHER",
 };
@@ -913,6 +914,11 @@ static int get_irq_affinity(struct hfi1_devdata *dd,
 			set = &entry->rcv_intr;
 		scnprintf(extra, 64, "ctxt %u", rcd->ctxt);
 		break;
+	case IRQ_NETDEVCTXT:
+		rcd = (struct hfi1_ctxtdata *)msix->arg;
+		set = &entry->def_intr;
+		scnprintf(extra, 64, "ctxt %u", rcd->ctxt);
+		break;
 	default:
 		dd_dev_err(dd, "Invalid IRQ type %d\n", msix->type);
 		return -EINVAL;
@@ -985,6 +991,10 @@ void hfi1_put_irq_affinity(struct hfi1_devdata *dd,
 		if (rcd->ctxt != HFI1_CTRL_CTXT)
 			set = &entry->rcv_intr;
 		break;
+	case IRQ_NETDEVCTXT:
+		rcd = (struct hfi1_ctxtdata *)msix->arg;
+		set = &entry->def_intr;
+		break;
 	default:
 		mutex_unlock(&node_affinity.lock);
 		return;
diff --git a/drivers/infiniband/hw/hfi1/affinity.h b/drivers/infiniband/hw/hfi1/affinity.h
index 6a7e6ea..f94ed5d 100644
--- a/drivers/infiniband/hw/hfi1/affinity.h
+++ b/drivers/infiniband/hw/hfi1/affinity.h
@@ -1,5 +1,5 @@
 /*
- * Copyright(c) 2015 - 2018 Intel Corporation.
+ * Copyright(c) 2015 - 2020 Intel Corporation.
  *
  * This file is provided under a dual BSD/GPLv2 license.  When using or
  * redistributing this file, you may do so under either license.
@@ -52,6 +52,7 @@
 enum irq_type {
 	IRQ_SDMA,
 	IRQ_RCVCTXT,
+	IRQ_NETDEVCTXT,
 	IRQ_GENERAL,
 	IRQ_OTHER
 };
diff --git a/drivers/infiniband/hw/hfi1/chip.c b/drivers/infiniband/hw/hfi1/chip.c
index 07eec35..2117612 100644
--- a/drivers/infiniband/hw/hfi1/chip.c
+++ b/drivers/infiniband/hw/hfi1/chip.c
@@ -66,6 +66,7 @@
 #include "affinity.h"
 #include "debugfs.h"
 #include "fault.h"
+#include "netdev.h"
 
 uint num_vls = HFI1_MAX_VLS_SUPPORTED;
 module_param(num_vls, uint, S_IRUGO);
@@ -8480,6 +8481,49 @@ static void hfi1_rcd_eoi_intr(struct hfi1_ctxtdata *rcd)
 	local_irq_restore(flags);
 }
 
+/**
+ * hfi1_netdev_rx_napi - napi poll function to move eoi inline
+ * @napi - pointer to napi object
+ * @budget - netdev budget
+ */
+int hfi1_netdev_rx_napi(struct napi_struct *napi, int budget)
+{
+	struct hfi1_netdev_rxq *rxq = container_of(napi,
+			struct hfi1_netdev_rxq, napi);
+	struct hfi1_ctxtdata *rcd = rxq->rcd;
+	int work_done = 0;
+
+	work_done = rcd->do_interrupt(rcd, budget);
+
+	if (work_done < budget) {
+		napi_complete_done(napi, work_done);
+		hfi1_rcd_eoi_intr(rcd);
+	}
+
+	return work_done;
+}
+
+/* Receive packet napi handler for netdevs VNIC and AIP  */
+irqreturn_t receive_context_interrupt_napi(int irq, void *data)
+{
+	struct hfi1_ctxtdata *rcd = data;
+
+	receive_interrupt_common(rcd);
+
+	if (likely(rcd->napi)) {
+		if (likely(napi_schedule_prep(rcd->napi)))
+			__napi_schedule_irqoff(rcd->napi);
+		else
+			__hfi1_rcd_eoi_intr(rcd);
+	} else {
+		WARN_ONCE(1, "Napi IRQ handler without napi set up ctxt=%d\n",
+			  rcd->ctxt);
+		__hfi1_rcd_eoi_intr(rcd);
+	}
+
+	return IRQ_HANDLED;
+}
+
 /*
  * Receive packet IRQ handler.  This routine expects to be on its own IRQ.
  * This routine will try to handle packets immediately (latency), but if
diff --git a/drivers/infiniband/hw/hfi1/chip.h b/drivers/infiniband/hw/hfi1/chip.h
index b10e0bf..2c6f2de 100644
--- a/drivers/infiniband/hw/hfi1/chip.h
+++ b/drivers/infiniband/hw/hfi1/chip.h
@@ -1447,6 +1447,7 @@ int hfi1_set_ctxt_pkey(struct hfi1_devdata *dd, struct hfi1_ctxtdata *ctxt,
 irqreturn_t sdma_interrupt(int irq, void *data);
 irqreturn_t receive_context_interrupt(int irq, void *data);
 irqreturn_t receive_context_thread(int irq, void *data);
+irqreturn_t receive_context_interrupt_napi(int irq, void *data);
 
 int set_intr_bits(struct hfi1_devdata *dd, u16 first, u16 last, bool set);
 void init_qsfp_int(struct hfi1_devdata *dd);
diff --git a/drivers/infiniband/hw/hfi1/driver.c b/drivers/infiniband/hw/hfi1/driver.c
index c5ed6ed..d89fc8f 100644
--- a/drivers/infiniband/hw/hfi1/driver.c
+++ b/drivers/infiniband/hw/hfi1/driver.c
@@ -752,6 +752,39 @@ static noinline int skip_rcv_packet(struct hfi1_packet *packet, int thread)
 	return ret;
 }
 
+static void process_rcv_packet_napi(struct hfi1_packet *packet)
+{
+	packet->etype = rhf_rcv_type(packet->rhf);
+
+	/* total length */
+	packet->tlen = rhf_pkt_len(packet->rhf); /* in bytes */
+	/* retrieve eager buffer details */
+	packet->etail = rhf_egr_index(packet->rhf);
+	packet->ebuf = get_egrbuf(packet->rcd, packet->rhf,
+				  &packet->updegr);
+	/*
+	 * Prefetch the contents of the eager buffer.  It is
+	 * OK to send a negative length to prefetch_range().
+	 * The +2 is the size of the RHF.
+	 */
+	prefetch_range(packet->ebuf,
+		       packet->tlen - ((packet->rcd->rcvhdrqentsize -
+				       (rhf_hdrq_offset(packet->rhf)
+					+ 2)) * 4));
+
+	packet->rcd->rhf_rcv_function_map[packet->etype](packet);
+	packet->numpkt++;
+
+	/* Set up for the next packet */
+	packet->rhqoff += packet->rsize;
+	if (packet->rhqoff >= packet->maxcnt)
+		packet->rhqoff = 0;
+
+	packet->rhf_addr = (__le32 *)packet->rcd->rcvhdrq + packet->rhqoff +
+				      packet->rcd->rhf_offset;
+	packet->rhf = rhf_to_cpu(packet->rhf_addr);
+}
+
 static inline int process_rcv_packet(struct hfi1_packet *packet, int thread)
 {
 	int ret;
@@ -831,6 +864,36 @@ static inline void finish_packet(struct hfi1_packet *packet)
 }
 
 /*
+ * handle_receive_interrupt_napi_fp - receive a packet
+ * @rcd: the context
+ * @budget: polling budget
+ *
+ * Called from interrupt handler for receive interrupt.
+ * This is the fast path interrupt handler
+ * when executing napi soft irq environment.
+ */
+int handle_receive_interrupt_napi_fp(struct hfi1_ctxtdata *rcd, int budget)
+{
+	struct hfi1_packet packet;
+
+	init_packet(rcd, &packet);
+	if (last_rcv_seq(rcd, rhf_rcv_seq(packet.rhf)))
+		goto bail;
+
+	while (packet.numpkt < budget) {
+		process_rcv_packet_napi(&packet);
+		if (hfi1_seq_incr(rcd, rhf_rcv_seq(packet.rhf)))
+			break;
+
+		process_rcv_update(0, &packet);
+	}
+	hfi1_set_rcd_head(rcd, packet.rhqoff);
+bail:
+	finish_packet(&packet);
+	return packet.numpkt;
+}
+
+/*
  * Handle receive interrupts when using the no dma rtail option.
  */
 int handle_receive_interrupt_nodma_rtail(struct hfi1_ctxtdata *rcd, int thread)
@@ -1078,6 +1141,63 @@ int handle_receive_interrupt(struct hfi1_ctxtdata *rcd, int thread)
 }
 
 /*
+ * handle_receive_interrupt_napi_sp - receive a packet
+ * @rcd: the context
+ * @budget: polling budget
+ *
+ * Called from interrupt handler for errors or receive interrupt.
+ * This is the slow path interrupt handler
+ * when executing napi soft irq environment.
+ */
+int handle_receive_interrupt_napi_sp(struct hfi1_ctxtdata *rcd, int budget)
+{
+	struct hfi1_devdata *dd = rcd->dd;
+	int last = RCV_PKT_OK;
+	bool needset = true;
+	struct hfi1_packet packet;
+
+	init_packet(rcd, &packet);
+	if (last_rcv_seq(rcd, rhf_rcv_seq(packet.rhf)))
+		goto bail;
+
+	while (last != RCV_PKT_DONE && packet.numpkt < budget) {
+		if (hfi1_need_drop(dd)) {
+			/* On to the next packet */
+			packet.rhqoff += packet.rsize;
+			packet.rhf_addr = (__le32 *)rcd->rcvhdrq +
+					  packet.rhqoff +
+					  rcd->rhf_offset;
+			packet.rhf = rhf_to_cpu(packet.rhf_addr);
+
+		} else {
+			if (set_armed_to_active(&packet))
+				goto bail;
+			process_rcv_packet_napi(&packet);
+		}
+
+		if (hfi1_seq_incr(rcd, rhf_rcv_seq(packet.rhf)))
+			last = RCV_PKT_DONE;
+
+		if (needset) {
+			needset = false;
+			set_all_fastpath(dd, rcd);
+		}
+
+		process_rcv_update(last, &packet);
+	}
+
+	hfi1_set_rcd_head(rcd, packet.rhqoff);
+
+bail:
+	/*
+	 * Always write head at end, and setup rcv interrupt, even
+	 * if no packets were processed.
+	 */
+	finish_packet(&packet);
+	return packet.numpkt;
+}
+
+/*
  * We may discover in the interrupt that the hardware link state has
  * changed from ARMED to ACTIVE (due to the arrival of a non-SC15 packet),
  * and we need to update the driver's notion of the link state.  We cannot
diff --git a/drivers/infiniband/hw/hfi1/hfi.h b/drivers/infiniband/hw/hfi1/hfi.h
index 5798688..b45e4b9 100644
--- a/drivers/infiniband/hw/hfi1/hfi.h
+++ b/drivers/infiniband/hw/hfi1/hfi.h
@@ -385,11 +385,11 @@ struct hfi1_packet {
 	u32 rhqoff;
 	u32 dlid;
 	u32 slid;
+	int numpkt;
 	u16 tlen;
 	s16 etail;
 	u16 pkey;
 	u8 hlen;
-	u8 numpkt;
 	u8 rsize;
 	u8 updegr;
 	u8 etype;
@@ -1503,6 +1503,8 @@ struct hfi1_ctxtdata *hfi1_rcd_get_by_index_safe(struct hfi1_devdata *dd,
 int handle_receive_interrupt(struct hfi1_ctxtdata *rcd, int thread);
 int handle_receive_interrupt_nodma_rtail(struct hfi1_ctxtdata *rcd, int thread);
 int handle_receive_interrupt_dma_rtail(struct hfi1_ctxtdata *rcd, int thread);
+int handle_receive_interrupt_napi_fp(struct hfi1_ctxtdata *rcd, int budget);
+int handle_receive_interrupt_napi_sp(struct hfi1_ctxtdata *rcd, int budget);
 void set_all_slowpath(struct hfi1_devdata *dd);
 
 extern const struct pci_device_id hfi1_pci_tbl[];
diff --git a/drivers/infiniband/hw/hfi1/init.c b/drivers/infiniband/hw/hfi1/init.c
index a4a1b3a..95bff7d 100644
--- a/drivers/infiniband/hw/hfi1/init.c
+++ b/drivers/infiniband/hw/hfi1/init.c
@@ -374,6 +374,7 @@ int hfi1_create_ctxtdata(struct hfi1_pportdata *ppd, int numa,
 		rcd->numa_id = numa;
 		rcd->rcv_array_groups = dd->rcv_entries.ngroups;
 		rcd->rhf_rcv_function_map = normal_rhf_rcv_functions;
+		rcd->msix_intr = CCE_NUM_MSIX_VECTORS;
 
 		mutex_init(&rcd->exp_mutex);
 		spin_lock_init(&rcd->exp_lock);
diff --git a/drivers/infiniband/hw/hfi1/msix.c b/drivers/infiniband/hw/hfi1/msix.c
index 7574f2b..7559875e 100644
--- a/drivers/infiniband/hw/hfi1/msix.c
+++ b/drivers/infiniband/hw/hfi1/msix.c
@@ -49,6 +49,7 @@
 #include "hfi.h"
 #include "affinity.h"
 #include "sdma.h"
+#include "netdev.h"
 
 /**
  * msix_initialize() - Calculate, request and configure MSIx IRQs
@@ -140,7 +141,7 @@ static int msix_request_irq(struct hfi1_devdata *dd, void *arg,
 	ret = pci_request_irq(dd->pcidev, nr, handler, thread, arg, name);
 	if (ret) {
 		dd_dev_err(dd,
-			   "%s: request for IRQ %d failed, MSIx %lu, err %d\n",
+			   "%s: request for IRQ %d failed, MSIx %lx, err %d\n",
 			   name, irq, nr, ret);
 		spin_lock(&dd->msix_info.msix_lock);
 		__clear_bit(nr, dd->msix_info.in_use_msix);
@@ -160,7 +161,7 @@ static int msix_request_irq(struct hfi1_devdata *dd, void *arg,
 	/* This is a request, so a failure is not fatal */
 	ret = hfi1_get_irq_affinity(dd, me);
 	if (ret)
-		dd_dev_err(dd, "unable to pin IRQ %d\n", ret);
+		dd_dev_err(dd, "%s: unable to pin IRQ %d\n", name, ret);
 
 	return nr;
 }
@@ -204,6 +205,21 @@ int msix_request_rcd_irq(struct hfi1_ctxtdata *rcd)
 }
 
 /**
+ * msix_request_rcd_irq() - Helper function for RCVAVAIL IRQs
+ * for netdev context
+ * @rcd: valid netdev contexti
+ */
+int msix_netdev_request_rcd_irq(struct hfi1_ctxtdata *rcd)
+{
+	char name[MAX_NAME_SIZE];
+
+	snprintf(name, sizeof(name), DRIVER_NAME "_%d nd kctxt%d",
+		 rcd->dd->unit, rcd->ctxt);
+	return msix_request_rcd_irq_common(rcd, receive_context_interrupt_napi,
+					   NULL, name);
+}
+
+/**
  * msix_request_smda_ira() - Helper for getting SDMA IRQ resources
  * @sde: valid sdma engine
  *
diff --git a/drivers/infiniband/hw/hfi1/msix.h b/drivers/infiniband/hw/hfi1/msix.h
index 1a02ab7..42fab94 100644
--- a/drivers/infiniband/hw/hfi1/msix.h
+++ b/drivers/infiniband/hw/hfi1/msix.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) */
 /*
- * Copyright(c) 2018 Intel Corporation.
+ * Copyright(c) 2018 - 2020 Intel Corporation.
  *
  * This file is provided under a dual BSD/GPLv2 license.  When using or
  * redistributing this file, you may do so under either license.
@@ -59,7 +59,8 @@
 int msix_request_sdma_irq(struct sdma_engine *sde);
 void msix_free_irq(struct hfi1_devdata *dd, u8 msix_intr);
 
-/* VNIC interface */
+/* Netdev interface */
 void msix_vnic_synchronize_irq(struct hfi1_devdata *dd);
+int msix_netdev_request_rcd_irq(struct hfi1_ctxtdata *rcd);
 
 #endif
diff --git a/drivers/infiniband/hw/hfi1/netdev.h b/drivers/infiniband/hw/hfi1/netdev.h
index 8992dfe..6740ec3 100644
--- a/drivers/infiniband/hw/hfi1/netdev.h
+++ b/drivers/infiniband/hw/hfi1/netdev.h
@@ -87,4 +87,7 @@ struct hfi1_ctxtdata *hfi1_netdev_get_ctxt(struct hfi1_devdata *dd, int ctxt)
 void *hfi1_netdev_get_data(struct hfi1_devdata *dd, int id);
 void *hfi1_netdev_get_first_data(struct hfi1_devdata *dd, int *start_id);
 
+/* chip.c  */
+int hfi1_netdev_rx_napi(struct napi_struct *napi, int budget);
+
 #endif /* HFI1_NETDEV_H */


  parent reply	other threads:[~2020-02-10 13:19 UTC|newest]

Thread overview: 29+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-02-10 13:18 [PATCH for-next 00/16] New hfi1 feature: Accelerated IP Dennis Dalessandro
2020-02-10 13:18 ` [PATCH for-next 01/16] IB/hfi1: Add accelerated IP capability bit Dennis Dalessandro
2020-02-10 13:18 ` [PATCH for-next 02/16] IB/hfi1: Add functions to transmit datagram ipoib packets Dennis Dalessandro
2020-02-10 13:18 ` [PATCH for-next 03/16] IB/hfi1: Add the transmit side of a datagram ipoib RDMA netdev Dennis Dalessandro
2020-02-10 13:18 ` [PATCH for-next 04/16] IB/hfi1: Remove module parameter for KDETH qpns Dennis Dalessandro
2020-02-10 13:18 ` [PATCH for-next 05/16] IB/{rdmavt, hfi1}: Implement creation of accelerated UD QPs Dennis Dalessandro
2020-02-10 13:18 ` [PATCH for-next 06/16] IB/hfi1: RSM rules for AIP Dennis Dalessandro
2020-02-10 13:18 ` [PATCH for-next 07/16] IB/ipoib: Increase ipoib Datagram mode MTU's upper limit Dennis Dalessandro
2020-02-19 11:01   ` Erez Shitrit
2020-02-21 19:40     ` Dennis Dalessandro
2020-02-10 13:18 ` [PATCH for-next 08/16] IB/hfi1: Rename num_vnic_contexts as num_netdev_contexts Dennis Dalessandro
2020-02-10 13:19 ` [PATCH for-next 09/16] IB/hfi1: Add functions to receive accelerated ipoib packets Dennis Dalessandro
2020-02-10 13:19 ` Dennis Dalessandro [this message]
2020-02-10 13:19 ` [PATCH for-next 11/16] IB/hfi1: Add rx functions for dummy netdev Dennis Dalessandro
2020-02-10 13:19 ` [PATCH for-next 12/16] IB/hfi1: Activate the " Dennis Dalessandro
2020-02-10 13:19 ` [PATCH for-next 13/16] IB/{hfi1, ipoib, rdma}: Broadcast ping sent packets which exceeded mtu size Dennis Dalessandro
2020-02-19  0:42   ` Jason Gunthorpe
2020-02-21 19:40     ` Dennis Dalessandro
2020-02-21 23:32       ` Jason Gunthorpe
2020-03-20 13:53         ` Dennis Dalessandro
2020-02-19 13:41   ` Erez Shitrit
2020-02-21 19:40     ` Dennis Dalessandro
2020-02-10 13:19 ` [PATCH for-next 14/16] IB/hfi1: Add packet histogram trace event Dennis Dalessandro
2020-02-10 13:19 ` [PATCH for-next 15/16] IB/ipoib: Add capability to switch between datagram and connected mode Dennis Dalessandro
2020-02-10 13:20 ` [PATCH for-next 16/16] IB/hfi1: Enable the transmit side of the datagram ipoib netdev Dennis Dalessandro
2020-02-10 13:31 ` [PATCH for-next 00/16] New hfi1 feature: Accelerated IP Jason Gunthorpe
2020-02-10 17:36   ` Dennis Dalessandro
2020-02-10 18:32     ` Jason Gunthorpe
2020-02-11 21:58       ` Dennis Dalessandro

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