cq.c

  1/*
  2 * Copyright (c) 2013-2015, Mellanox Technologies. All rights reserved.
  3 *
  4 * This software is available to you under a choice of one of two
  5 * licenses.  You may choose to be licensed under the terms of the GNU
  6 * General Public License (GPL) Version 2, available from the file
  7 * COPYING in the main directory of this source tree, or the
  8 * OpenIB.org BSD license below:
  9 *
 10 *     Redistribution and use in source and binary forms, with or
 11 *     without modification, are permitted provided that the following
 12 *     conditions are met:
 13 *
 14 *      - Redistributions of source code must retain the above
 15 *        copyright notice, this list of conditions and the following
 16 *        disclaimer.
 17 *
 18 *      - Redistributions in binary form must reproduce the above
 19 *        copyright notice, this list of conditions and the following
 20 *        disclaimer in the documentation and/or other materials
 21 *        provided with the distribution.
 22 *
 23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 30 * SOFTWARE.
 31 */
 32
 33#include <linux/kernel.h>
 34#include <linux/hardirq.h>
 35#include <linux/mlx5/driver.h>
 36#include <rdma/ib_verbs.h>
 37#include <linux/mlx5/cq.h>
 38#include "mlx5_core.h"
 39#include "lib/eq.h"
 40
 41#define TASKLET_MAX_TIME 2
 42#define TASKLET_MAX_TIME_JIFFIES msecs_to_jiffies(TASKLET_MAX_TIME)
 43
 44void mlx5_cq_tasklet_cb(struct tasklet_struct *t)
 45{
 46	unsigned long flags;
 47	unsigned long end = jiffies + TASKLET_MAX_TIME_JIFFIES;
 48	struct mlx5_eq_tasklet *ctx = from_tasklet(ctx, t, task);
 49	struct mlx5_core_cq *mcq;
 50	struct mlx5_core_cq *temp;
 51
 52	spin_lock_irqsave(&ctx->lock, flags);
 53	list_splice_tail_init(&ctx->list, &ctx->process_list);
 54	spin_unlock_irqrestore(&ctx->lock, flags);
 55
 56	list_for_each_entry_safe(mcq, temp, &ctx->process_list,
 57				 tasklet_ctx.list) {
 58		list_del_init(&mcq->tasklet_ctx.list);
 59		mcq->tasklet_ctx.comp(mcq, NULL);
 60		mlx5_cq_put(mcq);
 61		if (time_after(jiffies, end))
 62			break;
 63	}
 64
 65	if (!list_empty(&ctx->process_list))
 66		tasklet_schedule(&ctx->task);
 67}
 68
 69void mlx5_add_cq_to_tasklet(struct mlx5_core_cq *cq,
 70			    struct mlx5_eqe *eqe)
 71{
 72	unsigned long flags;
 73	struct mlx5_eq_tasklet *tasklet_ctx = cq->tasklet_ctx.priv;
 74	bool schedule_tasklet = false;
 75
 76	spin_lock_irqsave(&tasklet_ctx->lock, flags);
 77	/* When migrating CQs between EQs will be implemented, please note
 78	 * that you need to sync this point. It is possible that
 79	 * while migrating a CQ, completions on the old EQs could
 80	 * still arrive.
 81	 */
 82	if (list_empty_careful(&cq->tasklet_ctx.list)) {
 83		mlx5_cq_hold(cq);
 84		/* If the tasklet CQ work list isn't empty, mlx5_cq_tasklet_cb()
 85		 * is scheduled/running and hasn't processed the list yet, so it
 86		 * will see this added CQ when it runs. If the list is empty,
 87		 * the tasklet needs to be scheduled to pick up the CQ. The
 88		 * spinlock avoids any race with the tasklet accessing the list.
 89		 */
 90		schedule_tasklet = list_empty(&tasklet_ctx->list);
 91		list_add_tail(&cq->tasklet_ctx.list, &tasklet_ctx->list);
 92	}
 93	spin_unlock_irqrestore(&tasklet_ctx->lock, flags);
 94
 95	if (schedule_tasklet)
 96		tasklet_schedule(&tasklet_ctx->task);
 97}
 98EXPORT_SYMBOL(mlx5_add_cq_to_tasklet);
 99
100static void mlx5_core_cq_dummy_cb(struct mlx5_core_cq *cq, struct mlx5_eqe *eqe)
101{
102	mlx5_core_err(cq->eq->core.dev,
103		      "CQ default completion callback, CQ #%u\n", cq->cqn);
104}
105
106#define MLX5_CQ_INIT_CMD_SN cpu_to_be32(2 << 28)
107/* Callers must verify outbox status in case of err */
108int mlx5_create_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq,
109		   u32 *in, int inlen, u32 *out, int outlen)
110{
111	int eqn = MLX5_GET(cqc, MLX5_ADDR_OF(create_cq_in, in, cq_context),
112			   c_eqn_or_apu_element);
113	u32 din[MLX5_ST_SZ_DW(destroy_cq_in)] = {};
114	struct mlx5_eq_comp *eq;
115	int err;
116
117	eq = mlx5_eqn2comp_eq(dev, eqn);
118	if (IS_ERR(eq))
119		return PTR_ERR(eq);
120
121	memset(out, 0, outlen);
122	MLX5_SET(create_cq_in, in, opcode, MLX5_CMD_OP_CREATE_CQ);
123	err = mlx5_cmd_do(dev, in, inlen, out, outlen);
124	if (err)
125		return err;
126
127	cq->cqn = MLX5_GET(create_cq_out, out, cqn);
128	cq->cons_index = 0;
129	cq->arm_sn     = 0;
130	cq->eq         = eq;
131	cq->uid = MLX5_GET(create_cq_in, in, uid);
132
133	/* Kernel CQs must set the arm_db address prior to calling
134	 * this function, allowing for the proper value to be
135	 * initialized. User CQs are responsible for their own
136	 * initialization since they do not use the arm_db field.
137	 */
138	if (cq->arm_db)
139		*cq->arm_db = MLX5_CQ_INIT_CMD_SN;
140
141	refcount_set(&cq->refcount, 1);
142	init_completion(&cq->free);
143	if (!cq->comp)
144		cq->comp = mlx5_core_cq_dummy_cb;
145	/* assuming CQ will be deleted before the EQ */
146	cq->tasklet_ctx.priv = &eq->tasklet_ctx;
147	INIT_LIST_HEAD(&cq->tasklet_ctx.list);
148
149	/* Add to comp EQ CQ tree to recv comp events */
150	err = mlx5_eq_add_cq(&eq->core, cq);
151	if (err)
152		goto err_cmd;
153
154	/* Add to async EQ CQ tree to recv async events */
155	err = mlx5_eq_add_cq(mlx5_get_async_eq(dev), cq);
156	if (err)
157		goto err_cq_add;
158
159	cq->pid = current->pid;
160	err = mlx5_debug_cq_add(dev, cq);
161	if (err)
162		mlx5_core_dbg(dev, "failed adding CP 0x%x to debug file system\n",
163			      cq->cqn);
164
165	cq->irqn = eq->core.irqn;
166
167	return 0;
168
169err_cq_add:
170	mlx5_eq_del_cq(&eq->core, cq);
171err_cmd:
172	MLX5_SET(destroy_cq_in, din, opcode, MLX5_CMD_OP_DESTROY_CQ);
173	MLX5_SET(destroy_cq_in, din, cqn, cq->cqn);
174	MLX5_SET(destroy_cq_in, din, uid, cq->uid);
175	mlx5_cmd_exec_in(dev, destroy_cq, din);
176	return err;
177}
178EXPORT_SYMBOL(mlx5_create_cq);
179
180/* oubox is checked and err val is normalized */
181int mlx5_core_create_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq,
182			u32 *in, int inlen, u32 *out, int outlen)
183{
184	int err = mlx5_create_cq(dev, cq, in, inlen, out, outlen);
185
186	return mlx5_cmd_check(dev, err, in, out);
187}
188EXPORT_SYMBOL(mlx5_core_create_cq);
189
190int mlx5_core_destroy_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq)
191{
192	u32 in[MLX5_ST_SZ_DW(destroy_cq_in)] = {};
193	int err;
194
195	mlx5_debug_cq_remove(dev, cq);
196
197	mlx5_eq_del_cq(mlx5_get_async_eq(dev), cq);
198	mlx5_eq_del_cq(&cq->eq->core, cq);
199
200	MLX5_SET(destroy_cq_in, in, opcode, MLX5_CMD_OP_DESTROY_CQ);
201	MLX5_SET(destroy_cq_in, in, cqn, cq->cqn);
202	MLX5_SET(destroy_cq_in, in, uid, cq->uid);
203	err = mlx5_cmd_exec_in(dev, destroy_cq, in);
204	if (err)
205		return err;
206
207	synchronize_irq(cq->irqn);
208	mlx5_cq_put(cq);
209	wait_for_completion(&cq->free);
210
211	return 0;
212}
213EXPORT_SYMBOL(mlx5_core_destroy_cq);
214
215int mlx5_core_query_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq,
216		       u32 *out)
217{
218	u32 in[MLX5_ST_SZ_DW(query_cq_in)] = {};
219
220	MLX5_SET(query_cq_in, in, opcode, MLX5_CMD_OP_QUERY_CQ);
221	MLX5_SET(query_cq_in, in, cqn, cq->cqn);
222	return mlx5_cmd_exec_inout(dev, query_cq, in, out);
223}
224EXPORT_SYMBOL(mlx5_core_query_cq);
225
226int mlx5_core_modify_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq,
227			u32 *in, int inlen)
228{
229	u32 out[MLX5_ST_SZ_DW(modify_cq_out)] = {};
230
231	MLX5_SET(modify_cq_in, in, opcode, MLX5_CMD_OP_MODIFY_CQ);
232	MLX5_SET(modify_cq_in, in, uid, cq->uid);
233	return mlx5_cmd_exec(dev, in, inlen, out, sizeof(out));
234}
235EXPORT_SYMBOL(mlx5_core_modify_cq);
236
237int mlx5_core_modify_cq_moderation(struct mlx5_core_dev *dev,
238				   struct mlx5_core_cq *cq,
239				   u16 cq_period,
240				   u16 cq_max_count)
241{
242	u32 in[MLX5_ST_SZ_DW(modify_cq_in)] = {};
243	void *cqc;
244
245	MLX5_SET(modify_cq_in, in, cqn, cq->cqn);
246	cqc = MLX5_ADDR_OF(modify_cq_in, in, cq_context);
247	MLX5_SET(cqc, cqc, cq_period, cq_period);
248	MLX5_SET(cqc, cqc, cq_max_count, cq_max_count);
249	MLX5_SET(modify_cq_in, in,
250		 modify_field_select_resize_field_select.modify_field_select.modify_field_select,
251		 MLX5_CQ_MODIFY_PERIOD | MLX5_CQ_MODIFY_COUNT);
252
253	return mlx5_core_modify_cq(dev, cq, in, sizeof(in));
254}
255EXPORT_SYMBOL(mlx5_core_modify_cq_moderation);