KR20160106999A - Memory Management Apparatus and Method for Supporting Partial Release of Memory Allocation - Google Patents

Abstract

The present invention relates to a memory management apparatus, and a method. The memory management apparatus splits a memory, used to transfer data between protocol layers in a communication system or the like, into packets having a fixated size on each of the layers; and assigning the same. In a releasing method, the memory management apparatus is able to partially release the memory split by passing through the protocol layers. The memory management apparatus comprises: a packet storage memory storing header information and data of a data packet in a header, and a data area classified by a packet index; a release management memory managing a corresponding pointer and the packet index; and a memory manager determining whether or not partial release is performed.

Description

[0001] The present invention relates to a memory management apparatus and method for supporting partial release of memory allocation,

The present invention relates to a memory management apparatus and method, and more particularly, to a memory management apparatus and method for partially releasing a memory in a method of allocating and releasing a memory to a certain packet size in a communication system or the like.

In communication systems, protocols are divided into several layers to support communication protocols. For example, in a mobile communication system, IP data received from a network is transmitted to a modem layer through a Radio Link Control (RLC) layer and a MAC (Media Access Control) layer in order to process PDCP (Packet Data Convergence Protocol) Protocol. These protocols are made using each memory.

IP data consists of a memory management method for dividing and assembling data in the layer each time the layer is moved. In the data partitioning, physically divided data can be copied and assembled into another memory. However, such a copying method gives a very large processing overhead in a high-speed communication system and significantly degrades the performance of the system. In order to improve the performance, we are aiming at a zero copy system that transfers such partitioned data between layers using only partition information without copying them to memory.

However, there is a problem in the memory management in the non-copying system. For example, in the above example, the memory allocated by the memory manager to store IP data in the PDCP can be divided across each protocol layer. That is, the main memory allocated in the highest layer (eg, PDCP) is divided when the layer is moved, and is divided into a plurality of data memories and managed in the RLC layer. In this case, the memory manager generally requests the address of the allocated main memory, that is, a pointer, in order to release the memory allocated by the PDCP. However, since only the sub-memory pointers and sizes are managed through the hierarchical layer, it is difficult to manage the information about the main memory pointers allocated in the highest layer in such a protocol. In addition, It is very difficult to manage the release related information as a whole with respect to the entire divided memory.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a method and apparatus for allocating and releasing a memory used for transferring data between protocol layers in a communication system, A memory management apparatus and method capable of partly releasing a divided memory through a protocol layer.

According to an aspect of the present invention, there is provided a memory management apparatus for supporting partial release of a memory allocation according to an aspect of the present invention includes a header divided by a packet index, A packet storage memory for storing information and data, respectively; A release management memory for managing a corresponding pointer to which the packet storage memory allocation is partially released and the packet index; And managing and storing the size and the tag information of the data packet as the header information in the allocation of the packet storage memory and storing and managing data of the data packet in the data area, And a memory manager for determining whether or not the release target pointer is the tag information and whether the release target size is consistent with the size of the data packet using the target pointer and the release target size, , The memory manager may check whether or not the release object pointer is released in accordance with the presence or absence of the release object pointer in the release management memory in the partial release and if the release object pointer does not correspond to the release of the release object pointer, And manages the packet index in the release management memory.

The memory manager calculates the packet index i using the following equation for the release object pointer p,

i = FLOOR ((p - BASE_ADDRESS) / (MM1_S + DATA_S))

Here, FLOOR (k) is a maximum integer value not larger than k, BASE_ADDRESS is a reference address of the packet storage memory, MM1_S is a size of the header, and DATA_S is a size of the data area.

The memory manager updates the size of the data packet to a value obtained by subtracting the release object size from the size of the data packet of the header information if the size of the data packet is not 0 , And stores the packet index corresponding to the release object pointer in the release management memory to manage the packet index.

Wherein the release management memory includes a pointer storage memory for managing the partially released corresponding pointer and the packet index, and an auxiliary memory, and the memory manager further stores, in the storage corresponding to the packet index of the pointer storage memory, When the stack pointer corresponding to the packet index in the pointer storage memory reaches a predetermined maximum value, the releasing target pointer and the packet index corresponding to the releasing target pointer are stored in a storage separated by a stack pointer of the auxiliary memory And stores it.

Accordingly, although the storage size of the pointer storage memory is limited to a predetermined size, fast searching using the packet index is supported, and the auxiliary memory can be used without any distinction of the packet index to save memory.

A memory management method for supporting a partial release of a memory allocation in a memory management apparatus according to another aspect of the present invention includes the steps of storing the size of the data packet and the tag information as header information in a header in allocation of a packet storage memory Managing and storing data of the data packet in a data area; It is determined whether or not the release target pointer is the tag information and whether the release target size is consistent with the size of the data packet using the corresponding release object pointer and release object size in response to the release request of the allocation, ; And the memory manager, in the partial release, checks whether or not the release object pointer is released in accordance with the presence or absence of the release object pointer in the release management memory, and if the release object pointer does not correspond to the release of the release object pointer, And managing the packet index in the release management memory.

According to the memory management apparatus and method of the present invention, when a memory used for transferring data between protocol layers in a communication system or the like is allocated in each layer and a packet memory of a certain size is used in the memory allocation method By making the packet memory partly releasable, the performance of the system can be improved by smoothly configuring the non-memory copying system even if the data moving between the communication layers is divided.

FIG. 1 is a diagram for explaining a memory management apparatus supporting partial release of memory allocation according to an embodiment of the present invention. Referring to FIG.
2 is a diagram for explaining an example of partial release of the memory allocation of the present invention.
3 is a flowchart illustrating an operation of a memory management apparatus that supports partial release of memory allocation according to an embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same components are denoted by the same reference symbols as possible. In addition, detailed descriptions of known functions and / or configurations are omitted. The following description will focus on the parts necessary for understanding the operation according to various embodiments, and a description of elements that may obscure the gist of the description will be omitted. Also, some of the elements of the drawings may be exaggerated, omitted, or schematically illustrated. The size of each component does not entirely reflect the actual size, and therefore the contents described herein are not limited by the relative sizes or spacings of the components drawn in the respective drawings.

1 is a diagram for explaining a memory management apparatus 100 that supports partial release of memory allocation according to an embodiment of the present invention.

1, a memory management apparatus 100 according to an embodiment of the present invention includes a packet storage memory 110, a release management memory 120 including a pointer storage memory 121 and an auxiliary memory 122, , And a memory manager 130.

The memory manager 130 is responsible for overall control and management relating to memory allocation and release for storage of IP (Internet Protocol) data packets in the memory management device 100. [

The memory manager 130 allocates a storage of the packet storage memory 110 to store a Packet Data Convergence Protocol (PDCP), a Radio Link Control (RLC), a Media Access Control (MAC), and the like in a communication system such as a mobile communication system, And may store IP data packets processed in each of a plurality of signal processing layers such as a modem (physical layer).

The packet storage memory 110 is composed of a storage of a predetermined size (byte) from a base address, and is managed by a predetermined number of PN (natural number) divided storage, and a data packet is stored in each divided storage . Each partitioned storage includes a header MM1 [i] for storing header information such as a data size of a corresponding packet, predetermined tag (TAG) information, and a data area for storing data of the packet, and index i (i = 0 to PN-1), and the index i value corresponds to the ID (identifier) of the corresponding packet. It is assumed that the header MM1 [i] of each divided storage and the data area have sizes (bytes) of MM1_S (natural number) and DATA_S (natural number), respectively.

The pointer storage memory 121 and the auxiliary memory 122 of the release management memory 120 are storage for managing memory release. The auxiliary memory 122 is an auxiliary storage for use in the case of insufficient storage of the pointer storage memory 121. The auxiliary memory 122 stores information on each of the packets in a form of a pointer separator MM3.p and a packet index separator MM3.i. The auxiliary memory 122 may store information about all packets, but may be slower than the pointer storage memory 121. [ However, the auxiliary memory 122 has an advantage that all the packets can be used in common so that memory can be saved.

When receiving a memory allocation request from a predetermined processor in each layer, the memory manager 130 selects a usable location in the PN packet storage of the packet storage memory 110 and returns a pointer that is a start address of the data area of the packet do. When the memory manager 130 releases the allocation, the memory manager 130 receives the previously allocated pointer and releases the corresponding packet. This method is used in a general communication system. In the present invention, various concrete methods regarding memory allocation and release in the memory manager 130 can be applied.

2 is a diagram for explaining an example of partial release of the memory allocation of the present invention.

First, in releasing the memory allocation through the conventional memory manager, partial release is not possible, and only the entire allocated memory can be released. For example, when the memory allocation position is the main memory pointer p 'and the allocated size is the predetermined size size (size1 + size2 + size3) as shown in FIG. 2, p' The entire size is released to the user. However, in this conventional method, when a memory is allocated to p 'and size at a certain layer but it is divided into p1, p2 and p3 at another layer and p1, p2 and p3 are partially released, p ', it is necessary to separately manage p1, p2 and p3 in the corresponding layer. Therefore, memory usage is very complicated and difficult.

Accordingly, in the present invention, as shown in FIG. 1, between the processor (user) using the memory in each layer and the memory manager 130, a release management The memory 120 is placed so that the processor (user) can partially release the memory. In the memory management apparatus 100 according to the present invention that supports partial release of memory allocation, when the data allocated to the packet storage memory 110 is divided and released, the division management information is managed, Lt; RTI ID = 0.0 > 130 < / RTI > The operation of the components of the memory management apparatus 100 of the present invention can be implemented by software, hardware, or a combination thereof.

1, the memory manager 130 of the memory management device 100 of the present invention allocates a packet memory of a memory size or more required in the corresponding layer to a data area . For example, when a packet corresponding to MM1 [i] is allocated in FIG. 1, 'MM1 [i] address value + MM1_S' which is a start address (pointer) of a data area is allocated as a pointer p. 2, the memory manager 130 stores the requested memory size in the MM1 [i] .size portion of the header MM1 [i], and stores MM1 [i] in the header MM1 [i]. (Tag information) previously defined in the TAG.

The pointer storage memory 121 and the auxiliary memory 122 of the release management memory 120 store information for managing memory release, and are used as a storage for preventing duplication release. (Pointer p) is associated with each packet index i so that each piece of information can be accessed only by the packet index i value as in the delimiter MM2 [i] .p in the pointer storage memory 121, Is possible but the number of storable values is limited to MM2_MAX. The auxiliary memory 122 is an auxiliary storage for use in the case of insufficient storage of the pointer storage memory 121. The auxiliary memory 122 stores information on each of the packets in a form of a pointer separator MM3.p and a packet index separator MM3.i. The auxiliary memory 122 may store information about all packets, but may be slower than the pointer storage memory 121. [ However, the auxiliary memory 122 can share all the packets without distinguishing the packet index, thereby saving memory.

More specifically, the memory manager 130 stores the partial release target pointers p of the packet storage memory 110 in the pointer storage memory 121, and uses it to check for the de-duplication. The stack pointer MM2 [i] .sp (the stack pointer for each packet index i) of the pointer storage memory 121 is initialized to an initial value of 0, and when the packet index i of the MM2 [ i] .sp [MM2 [i] .sp] to MM2 [i] .p while incrementing the target pointer (p) by one.

In order to retrieve the p pointer in the pointer storage memory 121, the memory manager 130 reads the p value from the address MM2 [i] .p [0] to MM2 [i] .p [MM2 [i] Is checked.

When the stack pointer MM2 [i]. Sp reaches a predetermined maximum value MM2_MAX (natural number), the memory manager 130 can not store the pointer to the MM2 any longer. Therefore, the memory manager 130 stores the remaining partial release target pointers p in the auxiliary memory 122 do. In the communication system, the number of one packet to be segmented is predictable to some extent, so that MM2_MAX value can be set to operate within the number of MM2_MAX, if possible. However, in case of the worst case, the partial release target pointers p are divided into the pointer separator MM3.p and the packet index separator MM3.i in the auxiliary memory 122 only when the number of MM2_MAX is insufficient.

That is, like the pointer storage memory 121, the partial release target pointers p are stored in the auxiliary memory 122 and used for checking the redundancy release. The auxiliary memory 122 is a memory that is similar in function to the pointer storage memory 121, but is storable for all packets other than the specific packet. The auxiliary memory 122 includes a stack pointer MM3.sp for specifying the number of pointer p storage, MM3.p [n] for storing each pointer p, and MM3 for specifying the number of packets to which the pointer belongs. Information is stored and read by delimiters such as i [n]. MM3.sp is set to 0 at system initialization.

The memory manager 130 stores the pointer p in the MM3.p [MM3.sp] position and stores the packet index i in the MM3.i [MM3.sp] while incrementing the stack pointer MM3.sp by one .

In the process of deleting the pointer p in the auxiliary memory 122, when the pointer p corresponding to the i-th packet is deleted, the memory manager 130 sets the value of MM3.i [n] to n = 0 to MM3.sp-1 and searches for a location having a packet index i value. For example, if the value of MM3.i [x] is equal to the packet index i, the value of MM3.i [MM3.sp-1] and MM3.p [MM3.sp-1] .i [x] and MM3.p [x] and decrements MM3.sp by one.

In order to retrieve the p pointer in the auxiliary memory 122, the memory manager 130 checks whether the address MM3.p [0] through MM3.p [MM2 [i] .sp -1] matches the p value.

Hereinafter, the operation of the memory management apparatus 100 according to an embodiment of the present invention will be described in more detail with reference to the flowchart of FIG.

First, an IP data packet is stored in the packet storage memory 110 in each of a plurality of signal processing layers such as a PDCP, an RLC, an AC, and a modem (physical layer) in a communication system such as a mobile communication system or an Internet system, The pointer p and the release target size may be specified to request release of the memory allocation (S110). The size of the release object size is a size such as a byte unit starting from the release target pointer p to the following last address to be released.

Accordingly, in order to check whether the release object pointer p is the main memory pointer (corresponding to p '= p1 in FIG. 2), the memory manager 130 stores the value before the release object pointer p in the packet storage memory 110 (I)] .size of the packet storage memory 110. If the size matches the MM1 [i] .TAG of the packet storage memory 110, (S121), the corresponding release request is granted and the process ends (S181). This corresponds to the case where the allocated memory is freely released for all the data areas without division. The memory manager 130 may manage the corresponding main memory pointer p '= p1 that has been released after allocation to allocate the memory for another memory allocation request.

If the release target pointer p is not the main memory pointer (corresponding to p1 in FIG. 2) or the release target pointer p is the main memory pointer but the release target size does not match MM1 [i] .size , The memory manager 130 calculates how many packets belonging to the unlocking target pointer p belongs to, and discards the fractional part of the value calculated as shown in [Equation 1] and takes an integer value The packet index value i is calculated (S130). FLOOR (k) is the maximum integer value not greater than k. I calculated in this way becomes the packet index value i in Fig.

[Equation 1]

i = FLOOR ((p - BASE_ADDRESS) / (MM1_S + DATA_S))

After calculating the packet index value i, the memory manager 130 checks whether or not the release target pointer p has been released (S140). That is, the memory manager 130 searches whether the release target pointer p to be partially released exists in MM2 [i] .p of the pointer storage memory 121 and MM3.p of the auxiliary memory 122, If there is a release target pointer (p) in MM2 [i] .p or MM3.p, it is terminated because the release of the same part of memory is requested redundantly.

If the release target pointer p does not exist in MM2 [i] .p or MM3.p in step S140, the memory manager 130 deletes the previous MM1 [i] .size information of the packet storage memory 110 'MM1 [i] .size - release target size (size)' (S150). MM1 [i] .size corresponds to the memory size allocated in the memory allocation, and is updated by decrementing the partial release size each time the partial release is made.

If the updated MM1 [i] .size value is not 0, there exists a partial data area that has not yet been released with respect to the corresponding packet index i of the packet storage memory 110, so that the release target pointer p is stored in the pointer storage memory (S161) in the MM2 [i] of the main memory 121 or the MM3.p of the sub memory 122. [ That is, if the MM2 [i] .sp is not the maximum value MM2_MAX, the release target pointer p is stored in MM2 [i]. If MM2 [i] .sp is MM2_MAX, MM3.p and MM3.i And stores the release target pointer p and the packet index i, respectively. At this time, the stack pointer is incremented by 1 as described above.

If the value of MM1 [i] .size is 0 (S160), the entire data area of the packet index i portion is released, so the entire packet can be released. In order to release the packet, MM2 [i] .sp is initialized to 0 and MM3.p is searched to delete pointers belonging to the i packet (S170).

At this time, in order to release the memory allocated by the memory manager 130, the memory manager 130 calculates the main memory pointer p 'as shown in Equation (2) (S180). After calculating the main memory pointer p ', the memory manager 130 permits the corresponding release request and terminates (S181).

&Quot; (2) "

p '= BASE_ADDRESS + i * (MM1_S + DATA_S) + MM1_S

For example, in the example of FIG. 2, a memory of size 1 + size 2 + size 3 is allocated from the memory manager 130 in each layer for processing a packet, and then the divided data of size 1, size 2, . In this case, if partial release is performed on two pieces of data of p1 and p2, it can be updated to the value of MM1 [i] .size = size3 in S150, and if p3 portion is released thereafter, MM1 [i] The release is processed and managed by the memory manager 130 for the packet.

As described above, in the memory management apparatus 100 according to the present invention, when a memory used for transferring data between protocol layers in a communication system or the like is allocated in each layer and released, It is possible to partly release the data when the data is divided and used, so that the performance of the system can be improved by smoothly configuring the non-memory copying system even if the data moving between the communication layers is divided.

As described above, the present invention has been described with reference to particular embodiments, such as specific elements, and specific embodiments and drawings. However, it should be understood that the present invention is not limited to the above- Those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the essential characteristics of the invention. Therefore, the spirit of the present invention should not be construed as being limited to the embodiments described, and all technical ideas which are equivalent to or equivalent to the claims of the present invention are included in the scope of the present invention .

Packet storage memory 110,
The release management memory 120
Pointer storage memory 121,
The auxiliary memory 122,
The memory manager (130)

Claims (1)

A memory management device for supporting partial release of memory allocation,
A packet storage memory for storing header information and data of a data packet in a header and a data area separated by a packet index, respectively; A release management memory for managing a corresponding pointer to which the packet storage memory allocation is partially released and the packet index; And
And managing the size and the tag information of the data packet as the header information and managing the data packet by storing and managing the data of the data packet in the data area in the allocation of the packet storage memory, And a memory manager for determining whether or not the release object pointer is in the tag information and whether the release object size is equal to the size of the data packet by using the pointer and the release object size,
The memory manager may check whether or not the release object pointer is released in accordance with the presence or absence of the release object pointer in the release management memory in the partial release and if the release object pointer does not correspond to the release of the release object pointer, And manages the packet index in the release management memory.

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