A memory management unit (MMU) is disclosed. The MMU is configured to receive a translation request from a processing system, wherein the translation request specifies a virtual address to be translated, search a page table stored in a physical memory system for a page table entry that specifies the virtual address, receive a translation lookaside buffer invalidation (TLBI) signal from the processing system, wherein the TLBI signal specifies the virtual address, in response to receiving the TLBI signal specifying the virtual address, invalidate a translation lookaside buffer (TLB) entry in a TLB, wherein the invalidated TLB entry specifies the virtual address and restart the search of the page table for the page table entry that specifies the virtual address.

A system for memory synchronization of a multi-core system is provided, the system comprising: an assigning module which is configured to assign at least one memory partition to at least one core of the multi-core system; a mapping module which is configured to provide information for translation lookaside buffer shootdown for the multi-core system leveraged by sending an interrupt to the at least one core of the multi-core system, if a page table entry associated with the memory partition assigned to the at least one core is modified; and an interface module which is configured to provide an interface to the assigning module from user-space.

A method for operating translation look-aside buffers, TLBs, in a multiprocessor system. A purge request is received for purging one or more entries in the TLB. When the thread doesn't require access to the entries to be purged the execution of the purge request at the TLB may start. When an address translation request is rejected due to the TLB purge, a suspension time window may be set. During the suspension time window, the execution of the purge is suspended and address translation requests of the thread are executed. After the suspension window is ended the purge execution may be resumed. When the thread requires access to the entries to be purged, it may be blocked for preventing the thread sending address translation requests to the TLB and upon ending the purge request execution, the thread may be unblocked and the address translation requests may be executed.

An apparatus and method is described herein for providing robust speculative code section abort control mechanisms. Hardware is able to track speculative code region abort events, conditions, and/or scenarios, such as an explicit abort instruction, a data conflict, a speculative timer expiration, a disallowed instruction attribute or type, etc. And hardware, firmware, software, or a combination thereof makes an abort determination based on the tracked abort events. As an example, hardware may make an initial abort determination based on one or more predefined events or choose to pass the event information up to a firmware or software handler to make such an abort determination. Upon determining an abort of a speculative code region is to be performed, hardware, firmware, software, or a combination thereof performs the abort, which may include following a fallback path specified by hardware or software. And to enable testing of such a fallback path, in one implementation, hardware provides software a mechanism to always abort speculative code regions.

An apparatus and method is described herein for providing robust speculative code section abort control mechanisms. Hardware is able to track speculative code region abort events, conditions, and/or scenarios, such as an explicit abort instruction, a data conflict, a speculative timer expiration, a disallowed instruction attribute or type, etc. And hardware, firmware, software, or a combination thereof makes an abort determination based on the tracked abort events. As an example, hardware may make an initial abort determination based on one or more predefined events or choose to pass the event information up to a firmware or software handler to make such an abort determination. Upon determining an abort of a speculative code region is to be performed, hardware, firmware, software, or a combination thereof performs the abort, which may include following a fallback path specified by hardware or software. And to enable testing of such a fallback path, in one implementation, hardware provides software a mechanism to always abort speculative code regions.

Embodiments described herein provide a scalable coherency tracking implementation that utilizes shared virtual memory to manage data coherency. In one embodiment, coherency tracking granularity is reduced relative to existing coherency tracking solutions, with coherency tracking storage memory moved to memory as a page table metadata. For example and in one embodiment, storage for coherency state is moved from dedicated hardware blocks to system memory, effectively providing a directory structure that is limitless in size.

An apparatus and method are provided for maintaining address translation data within an address translation cache. The address translation cache has a plurality of entries, where each entry is used to store address translation data used when converting a virtual address into a corresponding physical address of a memory system. Control circuitry is used to perform an allocation process to determine the address translation data to be stored in each entry. The address translation cache is used to store address translation data of a plurality of different types representing address translation data specified at respective different levels of address translation within a multiple-level page table walk. The plurality of different types comprises a final level type of address translation data that identifies a full translation from the virtual address to the physical address, and at least one intermediate level type of address translation data that identifies a partial translation of the virtual address. The control circuitry is arranged, when performing the allocation process, to apply an allocation policy that permits each of the entries to be used for any of the different types of address translation data, and to store type identification data in association with each entry to enable the type of the address translation data stored therein to be determined. Such an approach enables very efficient usage of the address translation cache resources, for example by allowing the proportion of the entries used for full address translation data and the proportion of the entries used for partial address translation data to be dynamically adapted to changing workload conditions.

The instruction code including an instruction code stored in the area where the encrypted instruction code is stored in a non-rewritable format is authenticated using a specific key which is specific to the core where the instruction code is executed or an authenticated key by a specific key to perform an encryption processing for the input and output data between the core and the outside.

A system for generating predictions for a hardware table walk to find a map of a given virtual address to a corresponding physical address is disclosed. The system includes a plurality of memories, which each includes respective plurality of entries, each of which includes a prediction of a particular one of a plurality of buffers which includes a portion of a virtual to physical address translation map. A first circuit may generate a plurality of hash values to retrieve a plurality of predictions from the plurality of memories, where each has value depends on a respective address and information associated with a respective thread. A second circuit may select a particular prediction of the retrieved predictions to use based on a history of previous predictions.

A method for operating translation look-aside buffers, TLBs, in a multiprocessor system. A purge request is received for purging one or more entries in the TLB. When the thread doesn't require access to the entries to be purged the execution of the purge request at the TLB may start. When an address translation request is rejected due to the TLB purge, a suspension time window may be set. During the suspension time window, the execution of the purge is suspended and address translation requests of the thread are executed. After the suspension window is ended the purge execution may be resumed. When the thread requires access to the entries to be purged, it may be blocked for preventing the thread sending address translation requests to the TLB and upon ending the purge request execution, the thread may be unblocked and the address translation requests may be executed.