BACKGROUND OF THE INVENTION

The present invention relates generally to data processing and, in particular, to a translation load instruction that, when executed by a processor, causes a desired translation entry to be selectively loaded into an address translation structure.

A conventional multiprocessor (MP) computer system comprises multiple processing units (which can each include one or more processor cores and their various cache memories), input/output (I/O) devices, and data storage, which can include both system memory (which can be volatile or nonvolatile) and nonvolatile mass storage. In order to provide enough addresses for memory-mapped I/O operations and the data and instructions utilized by operating system and application software, MP computer systems typically reference an effective address space that includes a much larger number of effective addresses than the number of physical storage locations in the memory mapped I/O devices and system memory. Therefore, to perform memory-mapped I/O or to access system memory, a processor core within a computer system that utilizes effective addressing is required to translate an effective address into a real address assigned to a particular I/O device or a physical storage location within system memory.

In many architectures, the effective address space is partitioned into a number of memory pages, where each page has a respective associated address descriptor called a page table entry (PTE). The PTE corresponding to a particular memory page contains, among other information, the base effective address of the memory page as well as the associated base real address of the page frame, thereby enabling a processor core to translate any effective address within the memory page into a real address in system memory. The PTEs, which are created in system memory, for example, under the direction of operating system and/or hypervisor software, are collected in a page frame table.

In order to expedite the translation of effective addresses to real addresses during the processing of memory-mapped I/O and memory access instructions (hereinafter, together referred to simply as “memory-referent instructions”), a conventional processor core often employs, among other translation structures, a cache referred to as a translation lookaside buffer (TLB) to buffer recently accessed PTEs within the processor core. Of course, as data are moved into and out of physical storage locations in system memory (e.g., in response to the invocation of a new process or a context switch), the entries in the TLB must be updated to reflect the presence of the new data, and the TLB entries associated with data removed from system memory (e.g., paged out to nonvolatile mass storage) must be invalidated.

The present application recognizes that it would be useful and desirable to provide an improved technique for loading translation entries into address translation structures of a data processing system, such as the page frame table and TLBs.

BRIEF SUMMARY

In at least one embodiment, a processor core processes a translation load instruction including a protection field specifying a desired access protection to be specified in a translation entry for a memory page. Processing the translation load instruction includes calculating an effective address within the memory page and ensuring that a translation entry containing the desired access protection is stored within at least one translation structure of the data processing system.

