Engine control applications typically include computational activities consisting of periodic tasks, activated by timers, and engine-triggered tasks, activated at specific angular positions of the crankshaft. Such tasks are typically managed by a OSEK-compliant real-time kernel using a fixed-priority scheduler, as specified in the AUTOSAR standard adopted by most automotive industries. Recent theoretical results, however, have highlighted significant limitations of fixed-priority scheduling in managing engine-triggered tasks that could be solved by a dynamic scheduling policy. To address this issue, this paper proposes a new kernel implementation within the ERIKA Enterprise operating system, providing EDF scheduling for both periodic and engine-triggered tasks. The proposed kernel has been conceived to have an API similar to the AUTOSAR/OSEK standard one, limiting the effort needed to use the new kernel with an existing legacy application. The proposed kernel implementation is discussed and evaluated in terms of run-time overhead and footprint. In addition, a simulation framework is presented, showing a powerful environment for studying the execution of tasks under the proposed kernel.
OSEK-Like Kernel Support for Engine Control Applications under EDF Scheduling
BIONDI, ALESSANDRO;BUTTAZZO, Giorgio Carlo
2016-01-01
Abstract
Engine control applications typically include computational activities consisting of periodic tasks, activated by timers, and engine-triggered tasks, activated at specific angular positions of the crankshaft. Such tasks are typically managed by a OSEK-compliant real-time kernel using a fixed-priority scheduler, as specified in the AUTOSAR standard adopted by most automotive industries. Recent theoretical results, however, have highlighted significant limitations of fixed-priority scheduling in managing engine-triggered tasks that could be solved by a dynamic scheduling policy. To address this issue, this paper proposes a new kernel implementation within the ERIKA Enterprise operating system, providing EDF scheduling for both periodic and engine-triggered tasks. The proposed kernel has been conceived to have an API similar to the AUTOSAR/OSEK standard one, limiting the effort needed to use the new kernel with an existing legacy application. The proposed kernel implementation is discussed and evaluated in terms of run-time overhead and footprint. In addition, a simulation framework is presented, showing a powerful environment for studying the execution of tasks under the proposed kernel.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.