xref: /freebsd/sys/contrib/vchiq/interface/vchi/vchi_cfg_internal.h (revision bdd1243df58e60e85101c09001d9812a789b6bc4)
1 /**
2  * Copyright (c) 2010-2012 Broadcom. All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions, and the following disclaimer,
9  *    without modification.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. The names of the above-listed copyright holders may not be used
14  *    to endorse or promote products derived from this software without
15  *    specific prior written permission.
16  *
17  * ALTERNATIVELY, this software may be distributed under the terms of the
18  * GNU General Public License ("GPL") version 2, as published by the Free
19  * Software Foundation.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
22  * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
23  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
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26  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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32  */
33 
34 #ifndef VCHI_CFG_INTERNAL_H_
35 #define VCHI_CFG_INTERNAL_H_
36 
37 /****************************************************************************************
38  * Control optimisation attempts.
39  ***************************************************************************************/
40 
41 // Don't use lots of short-term locks - use great long ones, reducing the overall locks-per-second
42 #define VCHI_COARSE_LOCKING
43 
44 // Avoid lock then unlock on exit from blocking queue operations (msg tx, bulk rx/tx)
45 // (only relevant if VCHI_COARSE_LOCKING)
46 #define VCHI_ELIDE_BLOCK_EXIT_LOCK
47 
48 // Avoid lock on non-blocking peek
49 // (only relevant if VCHI_COARSE_LOCKING)
50 #define VCHI_AVOID_PEEK_LOCK
51 
52 // Use one slot-handler thread per connection, rather than 1 thread dealing with all connections in rotation.
53 #define VCHI_MULTIPLE_HANDLER_THREADS
54 
55 // Put free descriptors onto the head of the free queue, rather than the tail, so that we don't thrash
56 // our way through the pool of descriptors.
57 #define VCHI_PUSH_FREE_DESCRIPTORS_ONTO_HEAD
58 
59 // Don't issue a MSG_AVAILABLE callback for every single message. Possibly only safe if VCHI_COARSE_LOCKING.
60 #define VCHI_FEWER_MSG_AVAILABLE_CALLBACKS
61 
62 // Don't use message descriptors for TX messages that don't need them
63 #define VCHI_MINIMISE_TX_MSG_DESCRIPTORS
64 
65 // Nano-locks for multiqueue
66 //#define VCHI_MQUEUE_NANOLOCKS
67 
68 // Lock-free(er) dequeuing
69 //#define VCHI_RX_NANOLOCKS
70 
71 #endif /*VCHI_CFG_INTERNAL_H_*/
72