Virtual memory paging system and translation lookaside buffer with pagelets

A method to evict and write back a page that comprises a dirty pagelet to a secondary storage in a computing system, the method comprising:

• presenting a virtual address of the page and probing a translation lookaside buffer that handles pages with pagelets, to find a matching translation entry;
• presenting the virtual address of the page and reading one or more page tables to get an associated page table entry, the associated page table entry comprising pagelet states;
• upon finding the matching translation entry, updating the pagelet states in the associated page table entry and invalidating the matching translation entry in the translation lookaside buffer;
• checking pagelet states, and in response to finding the dirty pagelet, computing a physical address of the dirty pagelet, and a secondary storage address of the dirty pagelet;
• and
• setting up a direct memory access transaction to transfer the dirty pagelet to the secondary storage and starting the direct memory access transaction.

A method to insert a translation in a pagelet translation lookaside buffer in a system on a chip in a computing system, the method comprising:

• presenting a virtual page number of a page to insert and reading one or more page tables to get an associated page table entry comprising a physical page number, pagelet states and page attributes;
• probing the pagelet translation lookaside buffer that handles pages having pagelets to find a matching translation entry;
• in response to finding the matching translation entry, updating the matching translation entry;
• when no matching translation entry is found, then finding a replacement candidate entry in the pagelet translation lookaside buffer, and updating pagelet states of a corresponding page table entry in the one or more page tables, the corresponding page table entry associated with the replacement candidate entry;
• creating a new translation comprising the virtual page number, an associated access control identifier, the physical page number, the pagelet states, and the page attributes;
• and
• writing the new translation into the replacement candidate entry in the pagelet translation lookaside buffer.

A translation lookaside buffer with support for handling pagelets in a computing system comprising:

• a content addressable memory that holds at least one translation of a page, the page having pagelets;
• a content matching port coupled to the content addressable memory, wherein a transaction comprising a virtual address is presented at the content matching port, and wherein in response to the transaction a matching translation is generated;
• a critical pagelet determiner circuit that in response to the transaction determines a critical pagelet number of a critical pagelet, wherein the critical pagelet contains the location associated with the virtual address;
• and
• a physical address computation logic circuit that in response to the critical pagelet number generates a physical address.