drivers/infiniband/sw/rxe/rxe_task.h

   1 /*
   2  * Copyright (c) 2016 Mellanox Technologies Ltd. All rights reserved.
   3  * Copyright (c) 2015 System Fabric Works, Inc. All rights reserved.
   4  *
   5  * This software is available to you under a choice of one of two
   6  * licenses.  You may choose to be licensed under the terms of the GNU
   7  * General Public License (GPL) Version 2, available from the file
   8  * COPYING in the main directory of this source tree, or the
   9  * OpenIB.org BSD license below:
  10  *
  11  *         Redistribution and use in source and binary forms, with or
  12  *         without modification, are permitted provided that the following
  13  *         conditions are met:
  14  *
  15  *      - Redistributions of source code must retain the above
  16  *        copyright notice, this list of conditions and the following
  17  *        disclaimer.
  18  *
  19  *      - Redistributions in binary form must reproduce the above
  20  *        copyright notice, this list of conditions and the following
  21  *        disclaimer in the documentation and/or other materials
  22  *        provided with the distribution.
  23  *
  24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  31  * SOFTWARE.
  32  */
  33
  34 #ifndef RXE_TASK_H
  35 #define RXE_TASK_H
  36
  37 enum {
  38         TASK_STATE_START        = 0,
  39         TASK_STATE_BUSY         = 1,
  40         TASK_STATE_ARMED        = 2,
  41 };
  42
  43 /*
  44  * data structure to describe a 'task' which is a short
  45  * function that returns 0 as long as it needs to be
  46  * called again.
  47  */
  48 struct rxe_task {
  49         void                    *obj;
  50         struct tasklet_struct   tasklet;
  51         int                     state;
  52         spinlock_t              state_lock; /* spinlock for task state */
  53         void                    *arg;
  54         int                     (*func)(void *arg);
  55         int                     ret;
  56         char                    name[16];
  57         bool                    destroyed;
  58 };
  59
  60 /*
  61  * init rxe_task structure
  62  *      arg  => parameter to pass to fcn
  63  *      fcn  => function to call until it returns != 0
  64  */
  65 int rxe_init_task(void *obj, struct rxe_task *task,
  66                   void *arg, int (*func)(void *), char *name);
  67
  68 /* cleanup task */
  69 void rxe_cleanup_task(struct rxe_task *task);
  70
  71 /*
  72  * raw call to func in loop without any checking
  73  * can call when tasklets are disabled
  74  */
  75 int __rxe_do_task(struct rxe_task *task);
  76
  77 /*
  78  * common function called by any of the main tasklets
  79  * If there is any chance that there is additional
  80  * work to do someone must reschedule the task before
  81  * leaving
  82  */
  83 void rxe_do_task(unsigned long data);
  84
  85 /* run a task, else schedule it to run as a tasklet, The decision
  86  * to run or schedule tasklet is based on the parameter sched.
  87  */
  88 void rxe_run_task(struct rxe_task *task, int sched);
  89
  90 /* keep a task from scheduling */
  91 void rxe_disable_task(struct rxe_task *task);
  92
  93 /* allow task to run */
  94 void rxe_enable_task(struct rxe_task *task);
  95
  96 #endif /* RXE_TASK_H */