| [258] | 1 | ////////////////////////////////////////////////////////////////////////////////// |
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| 2 | // File : spin_lock.h |
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| 3 | // Date : 01/04/2012 |
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| 4 | // Author : alain greiner |
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| 5 | // Copyright (c) UPMC-LIP6 |
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| 6 | /////////////////////////////////////////////////////////////////////////////////// |
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| [368] | 7 | // The spin_lock.c and spin_lock.h files are part of the GIET-VM nano-kernel. |
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| 8 | // This library implements a user-level lock. |
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| 9 | // It is a simple binary lock, without waiting queue. |
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| 10 | // The lock_acquire() and lock_release() functions do not require a system call. |
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| 11 | // If the platform does not provide hardware cache coherence, the lock must be |
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| 12 | // declared in a non cacheable segment, |
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| 13 | // |
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| 14 | // When a lock is defined in the mapping, it has not to be declared in the |
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| 15 | // application code: it will be initialised in the boot phase, |
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| 16 | // and the vobj_get_vbase() system call (defined in stdio.c and stdio.h files) |
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| 17 | // can be used to get the virtual base address of the lock from it's name. |
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| 18 | /////////////////////////////////////////////////////////////////////////////////// |
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| [258] | 19 | |
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| 20 | #ifndef _GIET_SPIN_LOCK_H_ |
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| 21 | #define _GIET_SPIN_LOCK_H_ |
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| 22 | |
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| 23 | /////////////////////////////////////////////////////////////////////////////////// |
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| 24 | // lock structure |
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| 25 | /////////////////////////////////////////////////////////////////////////////////// |
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| 26 | |
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| [368] | 27 | typedef struct giet_lock_s |
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| 28 | { |
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| 29 | char name[60]; // lock name |
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| [258] | 30 | unsigned int value; // taken if value != 0 |
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| 31 | } giet_lock_t; |
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| 32 | |
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| 33 | ////////////////////////////////////////////////////////////////////////////// |
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| 34 | // access functions |
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| 35 | ////////////////////////////////////////////////////////////////////////////// |
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| 36 | |
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| [368] | 37 | extern void lock_acquire(giet_lock_t * lock); |
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| 38 | extern void lock_release(giet_lock_t * lock); |
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| [258] | 39 | |
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| 40 | #endif |
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| 41 | |
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| 42 | // Local Variables: |
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| 43 | // tab-width: 4 |
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| 44 | // c-basic-offset: 4 |
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| 45 | // c-file-offsets:((innamespace . 0)(inline-open . 0)) |
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| 46 | // indent-tabs-mode: nil |
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| 47 | // End: |
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| 48 | // vim: filetype=c:expandtab:shiftwidth=4:tabstop=4:softtabstop=4 |
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| 49 | |
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