linux/drivers/infiniband/hw/hfi1/ruc.c

// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
/*
 * Copyright(c) 2015 - 2018 Intel Corporation.
 */

#include <linux/spinlock.h>

#include "hfi.h"
#include "mad.h"
#include "qp.h"
#include "verbs_txreq.h"
#include "trace.h"

static int gid_ok(union ib_gid *gid, __be64 gid_prefix, __be64 id)
{ … }

/*
 *
 * This should be called with the QP r_lock held.
 *
 * The s_lock will be acquired around the hfi1_migrate_qp() call.
 */
int hfi1_ruc_check_hdr(struct hfi1_ibport *ibp, struct hfi1_packet *packet)
{ … }

/**
 * hfi1_make_grh - construct a GRH header
 * @ibp: a pointer to the IB port
 * @hdr: a pointer to the GRH header being constructed
 * @grh: the global route address to send to
 * @hwords: size of header after grh being sent in dwords
 * @nwords: the number of 32 bit words of data being sent
 *
 * Return the size of the header in 32 bit words.
 */
u32 hfi1_make_grh(struct hfi1_ibport *ibp, struct ib_grh *hdr,
		  const struct ib_global_route *grh, u32 hwords, u32 nwords)
{ … }

#define BTH2_OFFSET …

/**
 * build_ahg - create ahg in s_ahg
 * @qp: a pointer to QP
 * @npsn: the next PSN for the request/response
 *
 * This routine handles the AHG by allocating an ahg entry and causing the
 * copy of the first middle.
 *
 * Subsequent middles use the copied entry, editing the
 * PSN with 1 or 2 edits.
 */
static inline void build_ahg(struct rvt_qp *qp, u32 npsn)
{ … }

static inline void hfi1_make_ruc_bth(struct rvt_qp *qp,
				     struct ib_other_headers *ohdr,
				     u32 bth0, u32 bth1, u32 bth2)
{ … }

/**
 * hfi1_make_ruc_header_16B - build a 16B header
 * @qp: the queue pair
 * @ohdr: a pointer to the destination header memory
 * @bth0: bth0 passed in from the RC/UC builder
 * @bth1: bth1 passed in from the RC/UC builder
 * @bth2: bth2 passed in from the RC/UC builder
 * @middle: non zero implies indicates ahg "could" be used
 * @ps: the current packet state
 *
 * This routine may disarm ahg under these situations:
 * - packet needs a GRH
 * - BECN needed
 * - migration state not IB_MIG_MIGRATED
 */
static inline void hfi1_make_ruc_header_16B(struct rvt_qp *qp,
					    struct ib_other_headers *ohdr,
					    u32 bth0, u32 bth1, u32 bth2,
					    int middle,
					    struct hfi1_pkt_state *ps)
{ … }

/**
 * hfi1_make_ruc_header_9B - build a 9B header
 * @qp: the queue pair
 * @ohdr: a pointer to the destination header memory
 * @bth0: bth0 passed in from the RC/UC builder
 * @bth1: bth1 passed in from the RC/UC builder
 * @bth2: bth2 passed in from the RC/UC builder
 * @middle: non zero implies indicates ahg "could" be used
 * @ps: the current packet state
 *
 * This routine may disarm ahg under these situations:
 * - packet needs a GRH
 * - BECN needed
 * - migration state not IB_MIG_MIGRATED
 */
static inline void hfi1_make_ruc_header_9B(struct rvt_qp *qp,
					   struct ib_other_headers *ohdr,
					   u32 bth0, u32 bth1, u32 bth2,
					   int middle,
					   struct hfi1_pkt_state *ps)
{ … }

hfi1_make_ruc_hdr;

/* We support only two types - 9B and 16B for now */
static const hfi1_make_ruc_hdr hfi1_ruc_header_tbl[2] = …;

void hfi1_make_ruc_header(struct rvt_qp *qp, struct ib_other_headers *ohdr,
			  u32 bth0, u32 bth1, u32 bth2, int middle,
			  struct hfi1_pkt_state *ps)
{ … }

/* when sending, force a reschedule every one of these periods */
#define SEND_RESCHED_TIMEOUT …

/**
 * hfi1_schedule_send_yield - test for a yield required for QP
 * send engine
 * @qp: a pointer to QP
 * @ps: a pointer to a structure with commonly lookup values for
 *      the send engine progress
 * @tid: true if it is the tid leg
 *
 * This routine checks if the time slice for the QP has expired
 * for RC QPs, if so an additional work entry is queued. At this
 * point, other QPs have an opportunity to be scheduled. It
 * returns true if a yield is required, otherwise, false
 * is returned.
 */
bool hfi1_schedule_send_yield(struct rvt_qp *qp, struct hfi1_pkt_state *ps,
			      bool tid)
{ … }

void hfi1_do_send_from_rvt(struct rvt_qp *qp)
{ … }

void _hfi1_do_send(struct work_struct *work)
{ … }

/**
 * hfi1_do_send - perform a send on a QP
 * @qp: a pointer to the QP
 * @in_thread: true if in a workqueue thread
 *
 * Process entries in the send work queue until credit or queue is
 * exhausted.  Only allow one CPU to send a packet per QP.
 * Otherwise, two threads could send packets out of order.
 */
void hfi1_do_send(struct rvt_qp *qp, bool in_thread)
{ … }