JP5246014B2 - Virtualization program, virtualization processing method and apparatus - Google Patents

Description

  The present technology relates to a virtualization technology involving dynamic binary conversion.

  Many of today's computers operate by applying Dynamic Address Translation (DAT), and practical virtual machines are computers virtually configured on a host machine. It is necessary to support the DAT function on the guest machine.

  Also, dynamic binary conversion in a virtual machine (a technology that dynamically compiles machine language in the guest machine into machine language in the host machine when the virtual machine emulates the guest machine. This is JIT (Just In Time) compiling ( Compiling) is also a problem when using the DAT function on the guest machine. This occurs because a memory space larger than the physical memory can be used by the DAT function on the guest machine, so that the memory space to be subjected to dynamic binary conversion dynamically varies depending on the operating state of the guest machine.

  Further, by rewriting the DAT table, the mapping relationship between the guest virtual page, which is a virtual page in the guest machine, and the guest physical page, which is a physical page in the guest machine, is dynamically changed. Because of this change, the conversion code that is the result of the dynamic binary conversion may become invalid, and it becomes necessary to invalidate and delete the conversion code. Therefore, it is necessary to link DAT and conversion code management.

  Normally, a guest machine operates with DAT enabled, and a practical virtual machine needs to emulate a guest machine with the DAT function enabled. At this time, the shadow page method is often used.

The shadow page method is a method in which a virtual machine dynamically creates a shadow page table synchronized with a DAT table of a guest machine. In the shadow page method, the following management is performed.
(1) Initially, the shadow page table is empty.
(2) When the virtual machine detects a TLB (Translation Lookaside Buffer) fault in the guest machine, it emulates DAT. The result is registered in the shadow page table.
(3) When the DAT table of the guest machine is updated or when the TLB is deleted (for example, IBM System / 370 INVALIDATE PAGE TABLE ENTRY (IPTE) instruction, PURGE TLB (PTLB) instruction, etc.). If so, delete that part of the shadow page table.

  There are two types of dynamic binary conversion: a method for creating a conversion code for a guest virtual page and a method for creating a conversion code for a guest physical page. The former is the mainstream. In the case of the former method, when the DAT table is updated or a TLB operation is performed, the guest virtual page is deleted. Therefore, it is also necessary to delete the translation code translated based on the guest virtual page. is there. Therefore, when the shadow page method is used, it is necessary to manage the conversion code in conjunction with this shadow page table.

  FIG. 1 schematically shows a state in which conversion codes that have been subjected to dynamic binary conversion by the shadow page method are managed. The shadow table stores a host virtual page address, a pointer to a host physical page in which a code related to the host virtual page address is stored, and a conversion code as a result of code conversion of such code. A pointer to the host physical page is registered. The guest virtual page is converted into a host virtual page in the virtual machine (step (101)). A search in the shadow table is performed by using the address of the host virtual page as a key (step (102)), and the host physical page 1001 to be mapped by the DAT is converted into the conversion code 1002 which has been translated by the pointer of the corresponding entry. Can be reached. The size of the shadow table changes dynamically according to DAT. Although the shadow table is represented as a linear table in FIG. 1, it may actually be a hierarchical table or a hash table. Also, the management table of the host virtual page address and the host physical page, and the host virtual page address and the conversion code may be separated.

U.S. Pat. No. 7,299,337

Keith Adams et al: A Comparison of Software and Hardware Techniques for x86 Virtualization, ASPLOS '06 October 21-25, 2006, San Jose, California

  In the shadow page method, since the mapping relationship from the guest virtual page to the guest physical page is many-to-one, the size of the shadow page table is not fixed. Therefore, there is a problem that the shadow page table cannot be statically allocated prior to execution.

  In addition, the contents of the conversion code generated by dynamic binary conversion due to rewriting of the DAT table may become invalid, or the conversion code may not be used and may become unnecessary. Since such timing is not explicitly shown in the program on the guest machine, it is difficult to determine the timing for discarding the conversion code, and it is also difficult to maintain the shadow page table.

  That is, the use of the shadow page table is not always efficient in applying dynamic binary conversion in the virtual machine.

  Therefore, an object of the present technology is to provide a memory management technology that is efficient in applying dynamic binary conversion in a virtual machine.

  This virtualization processing method is a method for causing a host machine to execute a guest machine which is a virtual computer. When accessing a specific guest virtual page, the guest physical page address corresponding to the address of the specific guest virtual page is specified, and there are as many entries as there are guest physical pages, and each guest physical page A conversion table for storing a pointer to a host physical page corresponding to the guest virtual page address and a pointer to a conversion code that is a code obtained by converting the code stored in the host physical page for the host machine in the page address To read the entry for the specified guest physical page address and determine whether or not a pointer to the conversion code is included, and if the pointer to the conversion code is included, Included guest virtual page addresses and specific guest virtual page addresses If the comparison step for comparing the address and the guest virtual page address included in the read entry matches the address of the specific guest virtual page, a pointer to the conversion code included in the read entry And reading and executing the conversion code.

  Efficient memory management is possible when applying dynamic binary conversion in a virtual machine.

FIG. 1 is a diagram for explaining the prior art. FIG. 2 is a diagram for explaining the relationship between the memory spaces. FIG. 3 is a schematic diagram for explaining the outline of the present embodiment. FIG. 4 is a schematic diagram for explaining the outline of the present embodiment. FIG. 5 is a schematic diagram for explaining the outline of the present embodiment. FIG. 6 is a system configuration diagram of the host machine. FIG. 7 is a diagram showing a main processing flow in the present embodiment. FIG. 8 is a diagram showing a first process flow of the α table search process. FIG. 9 is a diagram illustrating a processing flow of registration processing. FIG. 10 is a diagram for explaining the shared memory. FIG. 11 is a diagram showing an outline of the α table for supporting the shared memory. FIG. 12 is a diagram showing a second processing flow of the α table search processing. FIG. 13 is a functional block diagram of a computer.

[Outline of the embodiment]
The CPU (Central Processing Unit) of the host machine virtually emulates the CPU of the guest machine by executing a CPU emulator described below. FIG. 2 shows the arrangement of the virtual and physical memory spaces in the host machine on which the CPU emulator operates and the correspondence between the virtual memory space and the physical memory space in the guest machine that is virtually executed by the CPU emulator.

  The left side of FIG. 2 schematically shows the memory access in the guest machine to be emulated, and the right side of FIG. 2 schematically shows the memory access emulated on the host machine.

  First, when the guest machine is activated, an area A for physical memory of the guest machine is secured on the host physical space. The CPU emulator operates in the host virtual space, and a window (that is, a guest virtual memory access area B) corresponding to the guest virtual space of the guest machine is provided on the host virtual space.

  In addition, when the guest machine is started, an α table area having a fixed number of entries corresponding to the number of pages included in the area A for reserved guest physical memory is also secured in the host physical space. Is set to a pointer to each page. Further, the host physical space also includes a conversion code management area for storing a conversion code that is a result of code conversion (also referred to as translation) of a code stored in the area A for guest physical memory for the host machine.

  In such a situation, it is assumed that the guest virtual page Page1 is mapped to the guest physical page Page2 (guest DAT in FIG. 2). In order to emulate this operation, the CPU emulator accesses the host virtual page Page4 corresponding to Page1 on the guest virtual memory access area B. If the host virtual page Page4 can be mapped to the host physical page Page3 by the DAT of the host machine, the host machine emulates the memory access of the guest machine. In the present embodiment, the consistency between the guest DAT and the host DAT is secured by the conventional technology, and will not be described further.

  In this embodiment, by introducing the α table described above, for example, when accessing the guest virtual page Page1, it is possible to efficiently access the corresponding host physical page Page3, and the corresponding host physical page The conversion code that is the result of the code conversion of the code stored in the page Page3 can be efficiently accessed.

  FIG. 3 schematically shows memory access using the α table. The α table is a table having fixed entries for the number of guest physical pages, and entries are arranged in the order of guest physical page numbers. The α table includes a guest virtual page address column X, a pointer Y to a corresponding host physical page, and a pointer to a conversion code that is a result of code conversion of the code stored in the corresponding host physical page. Column Z.

  The guest virtual page address column X stores the address value of the guest virtual page when dynamic binary conversion is performed on the code stored in the guest physical page. That is, a guest virtual page address in which the conversion code stored in the address of the conversion code column Z is valid is registered. The entry position and the column Y to the pointer to the host physical page represent the correspondence between the guest physical page and the host physical page.

  When a conversion code translated for the host machine is searched from the guest virtual page address using such an α table, the guest virtual page address is first converted to a guest physical page address using DAT. However, other methods such as a shadow page table may be used for this conversion.

  Then, the α table is searched using the guest physical page address as a key, and the corresponding entry is specified from the α table. Since the α tables are arranged in the order of guest physical page numbers, this search is a simple primary conversion. The entry specified by this search provides a pointer to the host physical page and a pointer to the conversion code, which can be easily accessed. However, unlike the shadow page method, when the guest virtual page and the guest physical page are many-to-one, the same entry is hit twice. Therefore, even if the conversion code can be identified by tracing the α table from a certain guest virtual page address, the conversion code is not necessarily translated from the guest virtual page of the search source. Therefore, the check is performed by comparing the address of the guest virtual page as the search source with the address value in the column X of the guest virtual page address in the α table. If they match, the conversion code is valid and executable. If they do not match, the conversion code is invalid and must be deleted. Similarly, the pointer included in the corresponding entry in the α table should be discarded.

  For example, as shown in FIG. 4, it is assumed that the guest virtual page address aaa is first registered in the column X of the α table. Then, when the guest virtual page address aaa is accessed, the guest physical page address AAA is obtained by DAT or the like, and when the α table is accessed with the guest physical page address AAA, the guest virtual page address column X includes a guest virtual page Since the address aaa is registered, if the pointer to the conversion code is registered in the column Z, the conversion code can be obtained.

  However, after that, the DAT table or the like is rewritten, and as shown in FIG. 5, the guest virtual page address aaa is mapped to the guest physical page address BBB by DAT or the like, and the guest virtual page address bbb is changed to the guest physical page address AAA by DAT or the like. Suppose that it comes to be mapped.

  At this time, if a process for deleting the conversion code is not performed after the DAT table or the like is rewritten, as shown in FIG. 5, the column X of the guest physical page address AAA entry contains a guest virtual page address. aaa remains, and in column Z, a pointer to the original conversion code remains.

  Then, when accessing the guest virtual page address bbb, the guest physical page address AAA is obtained by DAT or the like, and even if the guest physical page address AAA is accessed, it matches the address value aaa in the column X of the α table. Therefore, the pointer to the conversion code stored in the column Z and the conversion code itself are invalid. Therefore, the conversion code is deleted at this timing, and the pointer to the conversion code in the column Z of the α table is also deleted.

  On the other hand, when accessing the guest virtual page address aaa, even if the guest physical page address BBB is obtained by DAT or the like and the guest physical page address BBB is accessed, the initial value is registered in the column X of the α table. In this case, the pointer to the conversion code is not registered in the column Z.

  In both the case of FIG. 4 and FIG. 5, the host physical page address stored in the column Y of the α table is accessed here, the code conversion processing is performed on the stored code, and a new conversion is performed. Generate code. Then, the address of the conversion code is registered in the column Z of the α table, and the guest virtual page address that is valid this time is registered in the column X of the α table. In this way, it is possible to increase the execution speed of an appropriate conversion code in the future when accessing the same guest virtual page.

  Hereinafter, a specific description will be given of how processing is performed using the α table introduced in the present embodiment.

[Specific contents of this embodiment]
FIG. 6 shows a system configuration related to the α table of the present embodiment. When the host CPU of the host machine 1 executes the CPU emulator 100, the CPU of the guest machine is virtually emulated. The CPU emulator 100 includes an instruction interpreter 101, a conversion code search unit 103, and a dynamic binary conversion unit 105. The host main storage 200 of the host machine 1 is provided with a guest main storage area 201, an α table 203, and a conversion code management area 205. The guest main storage area 201 stores a guest program 2011 as a guest machine program, the α table 203 includes entries 2031 for the number of guest virtual pages, and the conversion code management area 205 includes A conversion code 2051 as a result of code conversion of the guest program 2011 is stored. As described above, the entry 2031 may point to the conversion code 2051.

  The CPU emulator 100 uses the first instruction interpreter 101 to execute the guest program 2011 on the guest main storage area 201 (FIG. 6 (1)). This is a verbatim interpretation of guest machine instructions stored in the guest main storage area 201. However, the execution speed of the instruction interpreter 101 is slow. In order to improve the performance, the dynamic binary conversion unit 105 generates a conversion code 2051 by converting the instruction sequence of the guest machine into a code for the host machine 1 and registers it in the conversion code management area 205. Furthermore, the corresponding entry 2031 of the α table 203 is also updated ((6) in FIG. 6). After the conversion code 2051 is registered, the conversion code search unit 103 of the CPU emulator 100 searches the α table 203 as described in the overview section of the present embodiment (FIG. 6 (4)), If it is found that the conversion code 2051 is stored in the conversion code management area 205, the CPU emulator 100 executes the conversion code 2051 instead of the verbal interpretation of the guest program 2011 (FIG. 6 (5)). This speeds up the processing.

  When the instruction interpreter 101 interprets and executes a guest machine instruction (for example, an IPTE instruction) that invalidates a part of the DAT table, the corresponding conversion code 2051 stored in the conversion code management area 205 is deleted. (FIG. 6 (2)). As described with reference to FIGS. 4 and 5, when an invalid conversion code 2051 is detected as a result of searching the α table 203, the conversion code search unit 103 searches the corresponding entry 2031 in the α table 203. The pointer to the conversion code 2051 is deleted, and the corresponding conversion code 2051 stored in the conversion code management area 205 is deleted (FIG. 6 (3)).

  When the instruction interpreter 101 interprets and executes a guest machine instruction that flushes the TLB (for example, an IBM System / 370 PTLB instruction) or rewrites the DAT table without an invalidation instruction of the DAT table, The consistency between the virtual page-physical page mapping relationship registered in the α table 203 and the actual DAT table is lost. Since this can be detected by the processing described in FIGS. 4 and 5, the α table 203 is not updated at the timing of the TLB flush operation or the DAT table rewrite operation. As a result, processing efficiency required for memory management can be improved.

  Next, the processing contents of the system of FIG. 6 will be described in detail with reference to FIGS. First, when the instruction interpreter 101 accesses a specific guest virtual page, the instruction interpreter 101 outputs the address of the guest virtual page to be accessed to the conversion code search unit 103, and the conversion code search unit 103 A guest physical page address is specified from the specific guest virtual page address using a DAT table or the like (FIG. 7: Step S1). Then, the conversion code search unit 103 performs an α table search process using the specified guest physical page address (step S3). The α table search process will be described with reference to FIG.

  First, the conversion code search unit 103 searches the α table 203 with the specified guest physical page address, and reads an entry of the guest physical page address (step S21). Then, the conversion code search unit 103 determines whether or not a pointer to the conversion code has been registered in the read entry (step S23). If no pointer to the conversion code is registered in the read entry, the process returns to the original process.

  On the other hand, if a pointer to the conversion code is registered in the read entry, the conversion code search unit 103 determines whether the specific guest virtual page address matches the guest virtual page address included in the entry. (Step S25). If they do not match, the conversion code search unit 103 deletes the conversion code indicated by the pointer to the conversion code included in the read entry (step S29), and deletes the pointer to the conversion code in the entry. (Step S30). Then, the process returns to the original process.

  On the other hand, if the specific guest virtual page address matches the guest virtual page address included in the entry, it means that a valid conversion code is obtained. A pointer to the conversion code in the issued entry is specified and held (step S27). Then, the process returns to the original process.

  Thus, an effective conversion code can be used if the two conditions are satisfied, and an effective conversion code cannot be used if at least one of the two conditions is not satisfied.

  Returning to the description of the processing in FIG. 7, the conversion code search unit 103 determines whether or not a pointer to the conversion code is specified and held as a result of step S3 (step S5). When the pointer to the conversion code is specified and held, the CPU emulator 100 reads out the corresponding conversion code from the conversion code management area 205 with the pointer to the conversion code and executes it (step S11).

  On the other hand, when the pointer to the conversion code is not specified, the conversion code search unit 103 sends a pointer to the host physical page included in the corresponding entry in the α table 203 and the guest to the dynamic binary conversion unit 105. A virtual page address and a guest physical page address are output, and the dynamic binary conversion unit 105 performs a well-known code conversion process on the code stored in the host physical page pointed to by the pointer and generates it. The converted code is stored in the conversion code management area 205 (step S7). Then, the dynamic binary conversion unit 105 performs registration processing in the α table 203 (step S9). The main registration process will be described with reference to FIG.

  The dynamic binary conversion unit 105 identifies the corresponding entry in the α table 203 using the guest physical page address received from the conversion code search unit 103 (step S31). Then, the guest virtual page address is overwritten and saved in the entry, and a pointer to the conversion code generated this time is also registered (step S33). As a result, correct data is registered in the corresponding entry of the α table 203, and the guest program 2011 is executed at high speed by using the data of the entry. Then, the process returns to the original process.

  Returning to the description of the processing in FIG. 7, after step S <b> 9, the CPU emulator 100 acquires the newly generated conversion code with a pointer to the conversion code held by the dynamic binary conversion unit 105, and converts the conversion code into the conversion code. Execute (Step S11).

  The above processing is repeated until the processing is completed (step S13), and a virtual machine capable of executing at high speed using dynamic binary conversion is realized.

  Instead of steps S7 and S9, there is a case in which dynamic binary conversion is asynchronously left to another processor for higher speed, and if conversion is not yet performed, a method of executing with an interpreter instead of conversion code may be adopted. .

  By executing the processing described above, it is possible to maintain the consistency that each entry of the α table 203 has a one-to-one mapping relationship with the guest virtual page.

  However, if the same processing is performed on the shared memory, the conversion code is frequently deleted, and there is a possibility that the performance degradation becomes a problem. The shared memory is a technique used in a general OS (Operating System), and is a technique that allows mapping from a plurality of virtual address spaces 1 to 3 to the same physical address space as shown in FIG. In particular, a general OS often places a kernel-related code in a shared memory. Therefore, when the α table method described above is applied as it is, the performance is not improved by dynamic binary conversion for the OS kernel.

  Therefore, the shared memory is configured to allow a plurality of guest virtual pages to correspond to the guest physical page. Specifically, as shown in FIG. 11, the guest virtual page address column X of the α table 203 is subdivided into a page sharing determination bit, a space identifier for distinguishing the virtual space, and a page address. Whether or not the access destination page is shared between virtual spaces is distinguished by a page sharing determination bit. If the access destination page is a non-shared page, the determination in step S25 in FIG. 8 is performed using both the space identifier and the page address. On the other hand, in the case of a shared memory, only the page address may be compared while ignoring the space identifier.

  In general, whether or not a page is used as a shared memory depends on the guest machine hardware characteristics (for example, common segment bit in IBM System / 370, global bit in Intel 386 PTE, etc.) and guest OS characteristics ( In the case of i386 / Linux, the latter half 1 GB of each virtual address space 4 GB is determined from the use of the kernel). Therefore, the dynamic binary conversion unit 105 prepared based on such information reflects information on whether or not the page to be converted is a shared memory in the page sharing determination bit when the α table entry is registered.

  Specifically, the α table search process of FIG. 12 is performed instead of FIG.

  First, the conversion code search unit 103 searches the α table 203 with the specified guest physical page address, and reads an entry of the guest physical page address (step S41). Then, the conversion code search unit 103 determines whether a pointer to the conversion code has been registered in the read entry (step S43). If no pointer to the conversion code is registered in the read entry, the process returns to the original process.

  On the other hand, if a pointer to the conversion code is registered in the read entry, the conversion code search unit 103 determines whether the page sharing determination bit included in the read entry is on (step S45). If the page sharing determination bit is on, since the page is a shared page, the conversion code search unit 103 receives the page address portion of the guest virtual page address received from the instruction interpreter 101 and the page address of the guest virtual page address in the read entry. It is determined whether the part matches (step S47). That is, the comparison is made by excluding the space identifier portion. If they match, the conversion code search unit 103 identifies and holds a pointer to the conversion code in the read entry (step S49). Then, the process returns to the original process. On the other hand, if they do not match, the conversion code search unit 103 deletes the conversion code indicated by the pointer to the conversion code included in the read entry (step S53). The pointer to the conversion code in the entry is deleted (step S55). Then, the process returns to the original process.

  If the page sharing determination bit in the read entry is off, the page is a non-shared page. Therefore, the conversion code search unit 103 receives the guest virtual page address received from the instruction interpreter 101, the space identifier and the page in the read entry. It is determined whether the guest virtual page address including the address matches (step S51). It is determined whether or not the non-shared memory matches including the space identifier. If they match, the conversion code search unit 103 proceeds to step S49. On the other hand, if they do not match, the process proceeds to step S53.

  If the processing as described above is performed, the α table can be utilized without any problem even when the shared memory exists.

  Although the embodiment of the present technology has been described above, the present technology is not limited to this. For example, the specific instruction names described above are examples, and correspond to any instruction that performs substantially the same function in another OS. Furthermore, as described above, the dynamic binary conversion unit 105 is provided in another CPU or the like, and the guest program 2011 is converted in a separate thread, and a pointer to the conversion code is occasionally added for the conversion completion page. It may be registered in the α table 203. In such a case, instead of steps S7 and S9 in FIG. 7, the instruction interpreter 101 sequentially executes the code obtained from the pointer to the host physical page obtained from the α table 203. If the conversion code has already been generated when accessing the same guest virtual page address later, the process can move to step S11 to obtain and execute the conversion code.

  Further, the processing flow is also an example, and if the same function can be achieved, the order may be changed or may be executed in parallel.

  The host machine 1 described above is a computer device, and as shown in FIG. 13, a memory 2501, a CPU 2503, a hard disk drive (HDD) 2505, a display control unit 2507 connected to the display device 2509, and a removable device. A drive device 2513 for the disk 2511, an input device 2515, and a communication control unit 2517 for connecting to a network are connected by a bus 2519. An operating system (OS: Operating System) and an application program for executing the processing in this embodiment are stored in the HDD 2505, and are read from the HDD 2505 to the memory 2501 when executed by the CPU 2503. If necessary, the CPU 2503 controls the display control unit 2507, the communication control unit 2517, and the drive device 2513 to perform necessary operations. Further, data in the middle of processing is stored in the memory 2501 and stored in the HDD 2505 if necessary. In an embodiment of the present technology, an application program for performing the above-described processing is stored in a computer-readable removable disk 2511 and distributed, and installed from the drive device 2513 to the HDD 2505. In some cases, the HDD 2505 may be installed via a network such as the Internet and the communication control unit 2517. Such a computer apparatus realizes various functions as described above by organically cooperating hardware such as the CPU 2503 and the memory 2501 described above, the OS, and necessary application programs.

  The present embodiment can be summarized as follows.

  This virtualization processing method is a method for causing a host machine to execute a guest machine which is a virtual computer. When accessing a specific guest virtual page, the guest physical page address corresponding to the address of the specific guest virtual page is specified, and there are as many entries as there are guest physical pages, and each guest physical page A conversion table for storing a pointer to a host physical page corresponding to the guest virtual page address and a pointer to a conversion code that is a code obtained by converting the code stored in the host physical page for the host machine in the page address To read the entry for the specified guest physical page address and determine whether or not a pointer to the conversion code is included, and if the pointer to the conversion code is included, Included guest virtual page addresses and specific guest virtual page addresses If the comparison step for comparing the address and the guest virtual page address included in the read entry matches the address of the specific guest virtual page, a pointer to the conversion code included in the read entry And reading and executing the conversion code.

  By using a conversion table as described above, the number of entries in the conversion table can be limited to the number of host physical pages, maintenance is easy, and dynamic binary conversion can be performed efficiently in a virtual machine. .

  Also, in this virtualization processing method, when the guest virtual page address included in the read entry does not match the address of the specific guest virtual page, the conversion code included in the read entry is converted to the conversion code. A step of deleting the conversion code stored in the page specified by the pointer may be further included. If the conditions described above are satisfied, it can be seen that dynamic address translation (DAT) table rewriting or TLB (Translation Lookaside Buffer) flush has occurred, so that unnecessary translation codes can be discarded. become. If it is known that a guest machine instruction that invalidates a part of the DAT table is executed, the corresponding conversion code is also deleted at this time, and the pointer to the conversion code of the corresponding entry in the conversion table is discarded. Good.

  In this virtualization processing method, the guest virtual page address included in the read entry does not match the address of the specific guest virtual page, or the read entry includes a pointer to the conversion code. If not, the code stored in the host physical page is read by the pointer to the host physical page included in the read entry and the code conversion process is performed, and the specified guest physical page address is Storing the address of a specific guest virtual page and the address of a host physical page in which the conversion code generated by the code conversion process is stored in the entry; executing the conversion code generated by the code conversion process; May be further included. Even when the conversion code cannot be executed immediately in this way, the storage location of the code to be subjected to the code conversion process can be identified from the corresponding entry of the conversion table, so that the code conversion process can be executed smoothly.

  Further, a valid guest virtual page address in the conversion table may include a page sharing determination bit, a space identifier, and a page address. In this case, in the comparison step described above, when the page sharing determination bit is set, the page address of the guest virtual page address included in the read entry and the address of the specific guest virtual page If the page sharing decision bit is not set, the space identifier and page address of a valid guest virtual page address included in the read entry and a specific guest virtual are compared. You may make it compare with the address of a page. For example, for a portion other than a memory area shared by a plurality of guest machines, a one-to-one relationship between a guest virtual page address and a host physical address can be expressed with the configuration described above. However, for the memory area shared by multiple guest machines, it is necessary to effectively represent the many-to-one mapping relationship, so that the conversion code can be used efficiently by adopting the configuration as described above. Become.

  It is possible to create a program for causing the host machine to perform the processing described above, and the program can be read by a computer such as a flexible disk, a CD-ROM, a magneto-optical disk, a semiconductor memory, and a hard disk. It is stored in a possible storage medium or storage device. Note that data being processed is temporarily stored in a storage device such as a computer memory.

  The following supplementary notes are further disclosed with respect to the embodiments including the above examples.

(Appendix 1)
A virtualization program for causing a host machine to execute a guest machine that is a virtual computer,
Identifying a guest physical page address corresponding to the address of the specific guest virtual page when accessing the specific guest virtual page;
The number of guest physical pages is equal to the number of guest physical pages, and the guest virtual page address and the corresponding host physical page pointer corresponding to the guest virtual page address and the code stored in the host physical page are converted for the host machine. A step of reading an entry for the specified guest physical page address from a conversion table for storing a pointer to a conversion code that is a generated code, and determining whether a pointer to the conversion code is included;
If the pointer to the conversion code is included, a comparison step of comparing the guest virtual page address included in the read entry with the address of the specific guest virtual page;
When the guest virtual page address included in the read entry matches the address of the specific guest virtual page, the conversion code is set by a pointer to the conversion code included in the read entry. Steps to read and execute;
Virtualization program for running

(Appendix 2)
If the guest virtual page address included in the read entry and the address of the specific guest virtual page do not match, the pointer to the conversion code included in the read entry is deleted. The virtualization program according to appendix 1, further comprising a step of deleting the conversion code stored in the page designated by the pointer.

(Appendix 3)
If the guest virtual page address included in the read entry does not match the address of the specific guest virtual page, or if the read entry does not include a pointer to the conversion code, read Reading a code stored in the host physical page by a pointer to the host physical page included in the entry, and performing a code conversion process;
Storing the address of the specified guest virtual page and the address of the host physical page in which the conversion code generated by the code conversion process is stored in the entry for the specified guest physical page address;
Executing the conversion code generated by the code conversion process;
The virtualization program according to appendix 1 or 2 for further executing

(Appendix 4)
The valid guest virtual page address in the translation table includes a page sharing determination bit, a space identifier, and a page address;
In the comparison step,
When the page sharing determination bit is set, the page address of the guest virtual page address included in the read entry and the address other than the space identifier of the address of the specific guest virtual page Compare the part with
When the page sharing determination bit is not set, the space identifier and the page address of the guest virtual page address included in the read entry are compared with the address of the specific guest virtual page. The virtualization program according to any one of appendices 1 to 3.

(Appendix 5)
A virtualization processing method for causing a host machine to execute a guest machine which is a virtual computer,
Identifying a guest physical page address corresponding to the address of the specific guest virtual page when accessing the specific guest virtual page;
The number of guest physical pages is equal to the number of guest physical pages, and the guest virtual page address and the corresponding host physical page pointer corresponding to the guest virtual page address and the code stored in the host physical page are converted for the host machine. A step of reading an entry for the specified guest physical page address from a conversion table for storing a pointer to a conversion code that is a generated code, and determining whether a pointer to the conversion code is included;
If the pointer to the conversion code is included, a comparison step of comparing the guest virtual page address included in the read entry with the address of the specific guest virtual page;
When the guest virtual page address included in the read entry matches the address of the specific guest virtual page, the conversion code is set by a pointer to the conversion code included in the read entry. Steps to read and execute;
A virtualization processing method including:

(Appendix 6)
A host machine that runs a guest machine that is a virtual computer,
Means for identifying a guest physical page address corresponding to an address of the specific guest virtual page when accessing the specific guest virtual page;
The number of guest physical pages is equal to the number of guest physical pages, and the guest virtual page address and the corresponding host physical page pointer corresponding to the guest virtual page address and the code stored in the host physical page are converted for the host machine. A memory for storing a conversion table for storing a pointer to the conversion code that is the generated code;
An entry for the specified guest physical page address is read from the conversion table, a determination is made as to whether a pointer to the conversion code is included, and if a pointer to the conversion code is included, a read is performed. The guest virtual page address included in the read entry is compared with the address of the specific guest virtual page, and the guest virtual page address included in the read entry matches the address of the specific guest virtual page A means for reading and executing the conversion code by a pointer to the conversion code included in the read entry;
Having a host machine.

DESCRIPTION OF SYMBOLS 1 Host machine 100 CPU emulator 200 Host main memory 101 Instruction interpreter 103 Conversion code search part 105 Dynamic binary conversion part 201 Guest main storage area 203 Alpha table 205 Conversion code management area 2011 Guest program 2051 Conversion code

Claims (6)

A virtualization program for causing a host machine to execute a guest machine that is a virtual computer,
Identifying a guest physical page address corresponding to the address of the specific guest virtual page when accessing the specific guest virtual page;
The number of guest physical pages is equal to the number of guest physical pages, and the guest virtual page address and the corresponding host physical page pointer corresponding to the guest virtual page address and the code stored in the host physical page are converted for the host machine. A step of reading an entry for the specified guest physical page address from a conversion table for storing a pointer to a conversion code that is a generated code, and determining whether a pointer to the conversion code is included;
If the pointer to the conversion code is included, a comparison step of comparing the guest virtual page address included in the read entry with the address of the specific guest virtual page;
When the guest virtual page address included in the read entry matches the address of the specific guest virtual page, the conversion code is set by a pointer to the conversion code included in the read entry. Steps to read and execute;
Virtualization program for running If the guest virtual page address included in the read entry and the address of the specific guest virtual page do not match, the pointer to the conversion code included in the read entry is deleted. The virtualization program according to claim 1, further comprising: deleting the conversion code stored in the page specified by the pointer. If the guest virtual page address included in the read entry does not match the address of the specific guest virtual page, or if the read entry does not include a pointer to the conversion code, read Reading a code stored in the host physical page by a pointer to the host physical page included in the entry, and performing a code conversion process;
Storing the address of the specified guest virtual page and the address of the host physical page in which the conversion code generated by the code conversion process is stored in the entry for the specified guest physical page address;
Executing the conversion code generated by the code conversion process;
The virtualization program according to claim 1 or 2, wherein the virtualization program is further executed. The valid guest virtual page address in the translation table includes a page sharing determination bit, a space identifier, and a page address;
In the comparison step,
When the page sharing determination bit is set, the page address of the guest virtual page address included in the read entry and the address other than the space identifier of the address of the specific guest virtual page Compare the part with
When the page sharing determination bit is not set, the space identifier and the page address of the guest virtual page address included in the read entry are compared with the address of the specific guest virtual page. The virtualization program according to any one of claims 1 to 3. A virtualization processing method for causing a host machine to execute a guest machine which is a virtual computer,
Identifying a guest physical page address corresponding to the address of the specific guest virtual page when accessing the specific guest virtual page;
The number of guest physical pages is equal to the number of guest physical pages, and the guest virtual page address and the corresponding host physical page pointer corresponding to the guest virtual page address and the code stored in the host physical page are converted for the host machine. A step of reading an entry for the specified guest physical page address from a conversion table for storing a pointer to a conversion code that is a generated code, and determining whether a pointer to the conversion code is included;
If the pointer to the conversion code is included, a comparison step of comparing the guest virtual page address included in the read entry with the address of the specific guest virtual page;
When the guest virtual page address included in the read entry matches the address of the specific guest virtual page, the conversion code is set by a pointer to the conversion code included in the read entry. Steps to read and execute;
A virtualization processing method including: A host machine that runs a guest machine that is a virtual computer,
Means for identifying a guest physical page address corresponding to an address of the specific guest virtual page when accessing the specific guest virtual page;
The number of guest physical pages is equal to the number of guest physical pages, and the guest virtual page address and the corresponding host physical page pointer corresponding to the guest virtual page address and the code stored in the host physical page are converted for the host machine. A memory for storing a conversion table for storing a pointer to the conversion code that is the generated code;
An entry for the specified guest physical page address is read from the conversion table, a determination is made as to whether a pointer to the conversion code is included, and if a pointer to the conversion code is included, a read is performed. The guest virtual page address included in the read entry is compared with the address of the specific guest virtual page, and the guest virtual page address included in the read entry matches the address of the specific guest virtual page A means for reading and executing the conversion code by a pointer to the conversion code included in the read entry;
Having a host machine.

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