专利快速检索-快速检索全球专利，免费商用专利数据库-IPRDB

1. 发明授权

US06230248B1 Method and apparatus for pre-validating regions in a virtual addressing scheme 失效
标题翻译：用于在虚拟寻址方案中预先验证区域的方法和装置
公开(公告)号：US06230248B1
公开(公告)日：2001-05-08
申请号：US09170140
申请日：1998-10-12
申请人： Stephen G. Burger , James O. Hays , Jonathan K. Ross , William R. Bryg , Rajiv Gupta , Gary N. Hammon , Koichi Yamada
发明人： Stephen G. Burger , James O. Hays , Jonathan K. Ross , William R. Bryg , Rajiv Gupta , Gary N. Hammon , Koichi Yamada
IPC分类号： G06F1216
CPC分类号： G06F12/1036
摘要： A method and apparatus pre-validate regions in a virtual addressing scheme by storing both the virtual region number (VRN) bits and region identifiers (RIDs) in translation lookaside buffer (TLB) entries. By storing both the VRN bits and RIDs in TLB entries, the region registers can be bypassed when performing most TLB accesses, thereby removing region registers the critical path of the TLB look-up process and enhancing system performance. A TLB in accordance with the present invention includes entries having a valid field, a region pre-validation valid (rpV) field, a virtual region number (VRN) field, a virtual page number (VPN) field, a region identifier (RID) field, a protection and access attributes field, and a physical page number (PPN) field. In addition, a set of region registers contains the RIDs that are active at any given time. When a virtual-to-physical entry is established for a page in a region having an RID stored in a region register, the RID and VRN are stored in the appropriate fields of the TLB entry. In addition, the valid field is set and the rpV field is set to indicate that the TLB entry contains an active VRN-to-RID mapping, thereby pre-validating the region. When a physical address is translated into a virtual address, a VRN and a VPN are extracted from the virtual address and provided to the TLB. The TLB is searched to find an entry having a set valid field, a set rpV field, and VRN and VPN fields containing entries matching the VRN and VPN extracted from the virtual address. If such an entry is found, the protection and access attributes field is used to determine whether the requested access is allowed. If the requested access is allowed, the PPN from the PPN field of the TLB entry is combined with an offset from the virtual address to produce a physical address that is used to complete the memory access.
摘要翻译：一种方法和装置通过将虚拟区域号（VRN）位和区域标识符（RID）存储在翻译后备缓冲器（TLB）条目中来对虚拟寻址方案中的区域进行预验证。通过将VRN位和RID都存储在TLB表中，可以在执行大多数TLB访问时旁路区域寄存器，从而去除区域寄存器中TLB查找过程的关键路径并提高系统性能。根据本发明的TLB包括具有有效字段，区域预验证有效（rpV）字段，虚拟区域号（VRN）字段，虚拟页号（VPN）字段），区域标识符（RID）字段，保护和访问属性字段以及物理页号（PPN）字段。此外，一组区域寄存器包含在任何给定时间处于活动状态的RID。当在具有存储在区域寄存器中的RID的区域中的页面建立虚拟到物理条目时，RID和VRN被存储在TLB条目的相应字段中。另外，设置有效字段，并且设置rpV字段以指示TLB条目包含活动的VRN到RID映射，从而预先验证该区域。当物理地址被转换为虚拟地址时，从虚拟地址提取VRN和VPN，并提供给TLB。搜索TLB以找到具有设置的有效字段，集合rpV字段的条目，以及包含与从虚拟地址提取的VRN和VPN匹配的条目的VRN和VPN字段。如果找到这样的条目，则使用保护和访问属性字段来确定所请求的访问是否被允许。如果允许所请求的访问，则来自TLB条目的PPN字段的PPN与来自虚拟地址的偏移组合，以产生用于完成存储器访问的物理地址。

IPRDB

热门服务

关于我们

友情链接

联系方式