Wind River Systems, Inc.

Thierry C Preyssler

Maarten Koning

David N Wilner

John Gordon

Andrew Gaiarsa

Kent Long

Cy H Myers

John C Fogelin

Keith Backensto

Pierre-Alain Darlet

Vincent Hue

Mati Sauks

Kevin McCombe

Surya Satyavolu

A non-transitory computer-readable storage medium storing a set of instructions executable by a processor, the set of instructions, when executed by the processor, causing the processor to perform operations including mapping a memory area storing a segment of code for a kernel of the system during an initialization time of a system. The operations also include executing the segment of code during the initialization time. The operations also include unmapping a portion of the memory area for the kernel after the segment of code has been executed.

Method and system for enforcing kernel mode access protection

A method including mapping a first portion of a virtual memory containing code of an operating system for access by a processor; receiving a call for an entry point of the operating system; and mapping, after receiving the call, a second portion of the virtual memory containing data for executing entry point code associated with the entry point for access by the processor. The processor executing the operating system code is permitted to access only data from the first and second portions of the virtual memory.

Least privileged operating system

A system and method deterministically switches context in a real-time scheduler to guarantee schedule periodicity. The method includes determining a time slice for each of the plurality of processes. The method includes determining a time slice switch duration between consecutive ones of the time slices. The method includes determining a starting point for each time slice. The method includes generating a schedule as a function of the time slices, the time slice switch durations, and the starting points of the time slices. The schedule includes an order for each of the time slices for a respective one of the plurality of processes. Each of the time slices and each of the time slice switch durations are required to run for their entire duration to guarantee a periodicity of the schedule.

System and method for deterministic context switching in a real-time scheduler

A system and method donates time from a first process to a second process. The method includes determining a time slice for each of a plurality of processes to generate a schedule therefrom. The method includes determining a time donation scheme for the first process, the time donation scheme indicative of a donation policy in which the execution time of the first process is donated to the second process. During execution of the processes, the method includes receiving a request from the first process for a time donation to the second process and executing the second process during the time slice of the first process.

System and method for execution time donation in a time-partitioning scheduler

A protection domain system is implemented to provide protection for applications executing in a computing environment. Protection domains are allocated system resources and may contain executing tasks. The protection domain system may allow tasks to access resources in other protection domains to which attachments have been made. Attachment is transparent to the software developer. The protection domain system provides flexibility in implementing operating system services and defining protection hierarchies.

Protection domains for a computer operating system

A computer system is provided comprising a core operating system and a system space having a number of memory locations. The core operating system creates a number of protection domains to partition the system space. Each of the partitions includes a partition operating system and a partition user application. Each partition operating system provides resource allocation services to the respective partition user application within the partition.

Two-level operating system architecture

A computer system and method for operating a computer system is provided which comprises a core operating system and a system space having a number of memory locations. The core operating system is arranged to create a number of protection domains to partition the system space into a core operating system space and a plurality of partitions. A partition operating system, a partition user application, and a partition alarm handler is provided in each partition. Each partition operating system provides resource allocation services to the respective partition user application within the partition. An alarm dispatcher and a system alarm handler is provided in the core operating system space. The alarm dispatcher is configured to receive alarms and to dispatch the alarms to one of the alarm handlers.

Health monitoring system for a partitioned architecture

A loading and linking process allows for the flexible loading and linking of software modules into a memory space, without regard to the order in which symbols are defined and referenced in such software modules, and without generating dangling references. An unloading process allows for software module unloading/unlinking from an already linked set of software modules, also without generating dangling references. A loading/linking system may be used to perform these processes.

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Oakland, CA, United States of America

Thierry C Preyssler