diff options
| author | Bjoern B. Brandenburg <bbb@cs.unc.edu> | 2011-01-28 12:24:58 -0500 |
|---|---|---|
| committer | Bjoern B. Brandenburg <bbb@cs.unc.edu> | 2011-02-01 16:30:37 -0500 |
| commit | 2dea9d5e7727b8474981557cbf925687b8f33865 (patch) | |
| tree | 96134311a3b67372e19a5f7eb232acb3d0be9b09 /include/litmus/locking.h | |
| parent | fd8ae31c74975c8499983c9831bff2b136b98434 (diff) | |
Litmus core: change plugin locking interface to generic 'allocate_lock()'
As the number of supported locking protocols is expected to rise,
hard-coding things like priority inheritance in the plugin interface
doesn't scale. Instead, use a new generic lock-ops approach. With this
approach, each plugin can define its own protocol implementation (or
use a generic one), and plugins can support multiple protocols without
having to change the plugin interface for each protocol.
Diffstat (limited to 'include/litmus/locking.h')
| -rw-r--r-- | include/litmus/locking.h | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/include/litmus/locking.h b/include/litmus/locking.h new file mode 100644 index 00000000000..4d7b870cb44 --- /dev/null +++ b/include/litmus/locking.h | |||
| @@ -0,0 +1,28 @@ | |||
| 1 | #ifndef LITMUS_LOCKING_H | ||
| 2 | #define LITMUS_LOCKING_H | ||
| 3 | |||
| 4 | struct litmus_lock_ops; | ||
| 5 | |||
| 6 | /* Generic base struct for LITMUS^RT userspace semaphores. | ||
| 7 | * This structure should be embedded in protocol-specific semaphores. | ||
| 8 | */ | ||
| 9 | struct litmus_lock { | ||
| 10 | struct litmus_lock_ops *ops; | ||
| 11 | int type; | ||
| 12 | }; | ||
| 13 | |||
| 14 | struct litmus_lock_ops { | ||
| 15 | /* Current task tries to obtain / drop a reference to a lock. | ||
| 16 | * Optional methods, allowed by default. */ | ||
| 17 | int (*open)(struct litmus_lock*, void* __user); | ||
| 18 | int (*close)(struct litmus_lock*); | ||
| 19 | |||
| 20 | /* Current tries to lock/unlock this lock (mandatory methods). */ | ||
| 21 | int (*lock)(struct litmus_lock*); | ||
| 22 | int (*unlock)(struct litmus_lock*); | ||
| 23 | |||
| 24 | /* The lock is no longer being referenced (mandatory method). */ | ||
| 25 | void (*deallocate)(struct litmus_lock*); | ||
| 26 | }; | ||
| 27 | |||
| 28 | #endif | ||