diff options
| author | Sebastian Huber <sebastian.huber@embedded-brains.de> | 2017-05-11 09:25:04 +0200 |
|---|---|---|
| committer | Sebastian Huber <sebastian.huber@embedded-brains.de> | 2017-05-11 09:26:09 +0200 |
| commit | 39773ce8bd21fcdf9d43739b56aba7a5fdedd828 (patch) | |
| tree | 9dd6ffdf67b755d87d5da919cd1038153c965890 /c-user/key_concepts.rst | |
| parent | hosts.rst: Correct Ubuntu instructions (diff) | |
| download | rtems-docs-39773ce8bd21fcdf9d43739b56aba7a5fdedd828.tar.bz2 | |
c-user: Replace pre-emption with preemption
Diffstat (limited to 'c-user/key_concepts.rst')
| -rw-r--r-- | c-user/key_concepts.rst | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/c-user/key_concepts.rst b/c-user/key_concepts.rst index cd41c7f..52e416c 100644 --- a/c-user/key_concepts.rst +++ b/c-user/key_concepts.rst @@ -271,7 +271,7 @@ Priority Inversion .. index:: priority inversion Priority inversion is a form of indefinite postponement which is common in -multitasking, pre-emptive executives with shared resources. Priority inversion +multitasking, preemptive executives with shared resources. Priority inversion occurs when a high priority tasks requests access to shared resource which is currently allocated to a low priority task. The high priority task must block until the low priority task releases the resource. This problem is exacerbated @@ -333,7 +333,7 @@ scheduler instance. In case the thread owning the mutex releases the mutex, then the normal priority of the thread is restored. Threads that wait for mutex ownership are not blocked with respect to the scheduler and instead perform a busy wait. The MrsP uses temporary thread migrations to foreign -scheduler instances in case of a pre-emption of the mutex owner. This locking +scheduler instances in case of a preemption of the mutex owner. This locking protocol is available since RTEMS 4.11. It was re-implemented in RTEMS 4.12 to overcome some shortcomings of the original implementation :cite:`Catellani:2015:MrsP`. |