KR102012261B1 - Memory Management Apparatus and Method for Supporting Partial Release of Memory Allocation - Google Patents

Abstract

According to the present invention, in a method of dividing and releasing memory used for data transfer between protocol layers in a communication system in a predetermined packet size in each layer, memory management capable of partially releasing the divided memory through the protocol layer An apparatus and method are provided.

Description

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 upon release in a manner of allocating and releasing a memory to a predetermined packet size in a communication system or the like.

In a communication system, protocols are divided into layers to support communication protocols. For example, in a mobile communication system, IP data received from a network is processed through a Packet Data Convergence Protocol (PDCP) and then transmitted to a modem layer through a Radio Link Control (RLC) and a Media Access Control (MAC) layer for transmission. Perform the protocol. These protocols are made using individual memories.

Whenever data is moved between layers, IP data is managed in a memory management manner to divide and assemble data in the layer. Although data partitioning may be performed by copying physically partitioned data to another memory and assembling it, such copying method may cause a very large processing overhead in a high-speed communication system and may significantly reduce the performance of the system. In order to improve performance, the present invention aims at a zero copy system that transfers the divided data using only the partition information without copying it to memory.

However, there is a problem in memory management in a copyless system. For example, in the above example, the memory allocated by the memory manager to store IP data in the PDCP may be partitioned through each protocol layer. That is, the main memory allocated in the uppermost layer (eg PDCP) is divided when the layer is moved, and is divided and managed in a plurality of data memories in the RLC layer. In this case, the memory manager generally requires the address of the allocated main memory, that is, the pointer, to release the allocated memory in the PDCP. However, since only the sub-memory pointers and sizes divided through the hierarchy are managed, not only is it difficult to manage information about the main memory pointers allocated in the top layer, but also when and when the divided data is released in each layer. Since the subjects can be different, it is very difficult to manage the release-related information as a whole.

Accordingly, the present invention has been made to solve the above-described problem, and an object of the present invention is to divide and allocate a memory used for data transfer between protocol layers in a communication system or the like to a predetermined packet size in each layer. The present invention provides a memory management apparatus and method capable of partially releasing partitioned memory while passing through a protocol layer.

First, to summarize the features of the present invention, a memory management apparatus for supporting partial release of memory allocation according to an aspect of the present invention for achieving the above object, the header of the data packet in the header and data area divided by the packet index A packet storage memory for storing information and data, respectively; A release management memory for managing the pointer and the packet index from which the packet storage memory allocation is partially released; And storing and managing the size and tag information of the data packet as the header information in the allocation of the packet storage memory, and storing and managing the data of the data packet in the data area, and corresponding release according to the release request of the allocation. And a memory manager for determining whether the release target pointer is the tag information and whether the release target size coincides with the size of the data packet by using a target pointer and the release target size. The memory manager checks whether the release target pointer is de-duplicated according to whether or not the release target pointer exists in the release management memory. The packet index is managed in the release management memory.

The memory manager calculates the packet index i with respect to the release target pointer p using the following equation,

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

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

The memory manager updates the size of the data packet by subtracting the size of the release target from the size of the data packet of the header information, if it does not correspond to the deduplication, and if the size of the updated data packet is not 0 And stores the packet index corresponding to the release target pointer in the release management memory.

The release management memory includes a pointer storage memory and an auxiliary memory for managing the partially released corresponding pointer, the packet index, and the memory manager is configured to release the stored data in a storage corresponding to the packet index of the pointer storage memory. A target pointer, and when the stack pointer corresponding to the packet index of the pointer storage memory reaches a predetermined maximum value, the release target pointer and the packet index corresponding thereto are stored in a storage divided by the stack pointer of the auxiliary memory. Store and manage.

Accordingly, although the storage size of the pointer storage memory is limited to a predetermined size, it supports fast retrieval using the packet index, and the auxiliary memory is used without distinguishing the packet index to save memory.

According to another aspect of the present invention, there is provided a memory management method for supporting partial release of memory allocation in a memory management apparatus. In the allocation of packet storage memory, the size and tag information of the data packet are stored in a header as header information. Managing and storing data of the data packet in a data area; Whether or not the release target pointer is the tag information and whether the release target size coincides with the size of the data packet using the release target pointer and release target size according to the allocation release request are partial releases. Determining whether or not; And the memory manager, in the partial release, checks whether the release target pointer is de-duplicated according to whether or not the release target pointer exists in the release management memory. Managing the packet index in the release management memory.

According to the memory management apparatus and method according to the present invention, in the case of allocating and releasing memory used for data transfer between protocol layers in a communication system or the like, when using a predetermined size of packet memory in the memory allocation scheme By partially releasing the packet memory, even if the data moving between the communication layers is divided, it is possible to smoothly configure the memory copyless system to increase the performance of the system.

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

Hereinafter, with reference to the accompanying drawings will be described in detail with respect to the present invention. In this case, the same components in each drawing are represented by the same reference numerals as much as possible. In addition, detailed descriptions of already known functions and / or configurations are omitted. The following description focuses on parts necessary for understanding the operation according to various embodiments, and descriptions of elements that may obscure the gist of the description are omitted. In addition, some components of the drawings may be exaggerated, omitted, or schematically illustrated. The size of each component does not entirely reflect the actual size, and thus the contents described herein are not limited by the relative size or spacing of the components drawn in the respective drawings.

FIG. 1 is a diagram for describing a memory management apparatus 100 supporting partial release of memory allocation according to an embodiment of the present invention.

Referring to FIG. 1, the memory management apparatus 100 according to an exemplary embodiment of the present disclosure may include a release management memory 120 including a packet storage memory 110, a pointer storage memory 121, and an auxiliary memory 122. , And memory manager 130.

The memory manager 130 is in charge of overall control and management related to memory allocation and release for storing IP (Internet Protocol) data packets in the memory management apparatus 100.

The memory manager 130 allocates a storage of the packet storage memory 110, and may use a packet data convergence protocol (PDCP), a radio link control (RLC), a media access control (MAC), a mobile communication system, an internet system, and the like. An IP data packet processed by each of a plurality of signal processing layers such as a modem (physical layer) can be stored.

The packet storage memory 110 consists of a storage of a predetermined size (byte) from a base address, and is managed as a predetermined number of divided storages of PNs (natural numbers) so that data packets are stored in each divided storage. Can be. Each partitioned storage includes a header MM1 [i] for storing header information such as data size of the packet, predetermined tag (TAG) information, and a data area for storing data of the packet, and index i (i = 0 ~ PN-1) can be used to distinguish the storage location of the data packet, and the index i value corresponds to the ID (identifier) of the packet. It is assumed that the header MM1 [i] and the data area of each partitioned storage 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 storages for managing memory release. The auxiliary memory 122 is an auxiliary storage for use when the storage of the pointer storage memory 121 is insufficient. The auxiliary memory 122 divides and stores information about each packet into a pointer delimiter MM3.p and a packet index delimiter MM3.i. The auxiliary memory 122 may store information on all packets, but the search may be slow compared to the pointer storage memory 121. However, the auxiliary memory 122 has an advantage of saving memory because all packets can be used in common.

When the memory manager 130 receives a memory allocation request from a predetermined processor in each layer, the memory manager 130 selects an available position among the PN packet stores of the packet storage memory 110 and returns a pointer that is a start address of the data area of the packet. do. In addition, when de-allocation, the memory manager 130 receives the pre-allocated pointer and releases the packet. This method is used in a general communication system. In the present invention, various specific methods related to memory allocation and release in the memory manager 130 may be applied.

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

First, in releasing memory allocation through the conventional memory manager, partial releasing is impossible and only the entire allocated memory can be released. For example, when the memory allocation position is the main memory pointer p 'and the allocation size is the predetermined size size (size1 + size2 + size3) as shown in FIG. 2, p' main memory pointer is required to release the p ', and p' Works by releasing the entire size for. However, in this conventional method, when a memory is allocated as p 'and size in one layer but divided into p1, p2, and p3 in another layer and used to partially release p1, p2, and p3, the existing memory manager Since only the release request for the entire size can be made using p ', the memory usage is very complicated and difficult because each processor (user) must manage separately for partial release of p1, p2, and p3 in the layer.

Accordingly, in the present invention, release management for preventing deduplication other than the packet storage memory 110 for partial release management of the memory between the processor (user) and the memory manager 130 using the memory in each layer as shown in FIG. 1. The memory 120 is provided so that the processor (user) can partially release the memory. In the memory management apparatus 100 of the present invention which supports partial release of memory allocation, the memory manager manages partition release information when the data allocated to the packet storage memory 110 is divided and released, thereby managing the memory manager in response to the partition release request. 130 handles and manages the appropriate release. Operation of the components of the memory management apparatus 100 of the present invention can be implemented in software, hardware, or a combination thereof.

In FIG. 1, when the memory manager 130 of the memory management apparatus 100 of the present invention allocates the storage of the packet storage memory 110, the memory size of the packet size required by the corresponding layer or more is set to the data area. Assign. For example, in FIG. 1, when a packet corresponding to MM1 [i] is allocated, 'MM1 [i] address value + MM1_S', which is a start address (pointer) of the data area, is allocated as a pointer p. As shown in FIG. 2, the memory manager 130 stores the memory size requested by the corresponding layer in the MM1 [i] .size portion of the header MM1 [i] and stores the MM1 [i] of the header MM1 [i]. A predetermined value (tag information) predefined in the TAG is stored.

The pointer storage memory 121 and the auxiliary memory 122 of the release management memory 120 store information for managing memory release, but are used as storage for preventing deduplication. The pointer storage memory 121 stores the association information (pointer p) in correspondence with each packet index i so that each information can be accessed only by the packet index i value, such as the separator MM2 [i] .p. This is possible, but the number that can be stored is limited to MM2_MAX. The auxiliary memory 122 is an auxiliary storage for use when the storage of the pointer storage memory 121 is insufficient. The auxiliary memory 122 divides and stores information about each packet into a pointer delimiter MM3.p and a packet index delimiter MM3.i. The auxiliary memory 122 may store information on all packets, but the search may be slow compared to the pointer storage memory 121. However, the auxiliary memory 122 has an advantage of saving memory because all packets can be used in common without distinguishing the packet index.

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 the same to check for deduplication. When allocating the packet index i of the packet storage memory 110, 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 the MM2 [ i] .sp is incremented by 1 and the partial release target pointers p are stored in MM2 [i] .p [MM2 [i] .sp].

In order to retrieve the p pointer from the pointer storage memory 121, the memory manager 130 stores the p value from the addresses MM2 [i] .p [0] to MM2 [i] .p [MM2 [i] .sp -1]. Check if it matches

When the stack pointer MM2 [i] .sp reaches a predetermined maximum value MM2_MAX (a natural number), it can no longer be stored in MM2, so the memory manager 130 stores the remaining partial release target pointers p in the auxiliary memory 122. do. Since the number of splitting of one packet in the communication system is predictable to some extent, the MM2_MAX value may be set to operate within the number of MM2_MAX whenever possible. However, in order to prepare for the worst case, the partial release target pointers p are stored in the auxiliary memory 122 by the pointer delimiter MM3.p and the packet index delimiter MM3.i 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 to check for deduplication. The auxiliary memory 122 is similar in function to the pointer storage memory 121 but is a memory capable of storing all packets other than a specific packet. The auxiliary memory 122 includes a stack pointer MM3.sp which designates the number of pointers p stored therein, MM3.p [n] where each pointer p is stored, and an MM3 for designating which packet the pointer belongs to. 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 at the position MM3.p [MM3.sp] while increasing the stack pointer MM3.sp by 1, and stores the packet index i at MM3.i [MM3.sp]. .

In the process of deleting the pointer p from the auxiliary memory 122, when the memory manager 130 deletes the pointer p corresponding to the i th packet, n = 3 = MM3.i [n]. Search from 0 to MM3.sp-1 to find the location with packet index i. For example, if the value of MM3.i [x] is equal to the packet index i, then the values of MM3.i [MM3.sp-1] and MM3.p [MM3.sp-1] located at MM3.sp-1 are converted to MM3. Store in .i [x] and MM3.p [x] and decrement MM3.sp by one.

To retrieve the p pointer from the secondary memory 122, the memory manager 130 checks whether the p value matches the addresses MM3.p [0] through MM3.p [MM2 [i] .sp -1].

Hereinafter, an operation of the memory management apparatus 100 according to an exemplary embodiment of the present invention will be described in more detail with reference to the flowchart of FIG. 3.

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

Accordingly, the memory manager 130 checks whether the release target pointer p is the main memory pointer (p '= p1 in FIG. 2), and the value before the release target pointer p of the packet storage memory 110. If it matches with the predetermined value MM1 [i] .TAG, and if they match each other (S120), whether or not the release target size is also equal to MM1 [i] .size of the packet storage memory 110. Check and match with each other (S121), permits the release request and ends (S181). This is the case where the allocated memory is released for all the data areas without partitioning. The memory manager 130 may manage the main memory pointer p '= p1 released after the allocation to allocate memory to another memory allocation request.

The release target pointer p above 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. (Ie, in case of partial release), the memory manager 130 calculates how many packets the pointer to be released (p) belongs to, and discards the decimal point from the value calculated as in Equation 1 and takes an integer value. The packet index value i is calculated (S130). FLOOR (k) is the largest integer value not greater than k. I calculated as above 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 the deduplication of the release target pointer p (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, the request is repeated because the same part of memory is repeatedly requested.

When the release target pointer p does not exist in the MM2 [i] .p or the MM3.p (S140), the memory manager 130 reads the previous MM1 [i] .size information of the packet storage memory 110. Update to 'MM1 [i] .size-release target size (size)' (S150). MM1 [i] .size corresponds to the memory size allocated when allocating memory, and is updated by decreasing the partial free size each time it is released.

At this time, if the updated MM1 [i] .size value is not 0, there is a partial data area which is not yet released for the corresponding packet index i of the packet storage memory 110, and thus the release target pointer p is replaced with a pointer storage memory ( Storage is managed in MM2 [i] of 121) or MM3.p of auxiliary memory 122 (S161). That is, if 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, the MM3.p and MM3.i are stored. Each stores a release target pointer p and a packet index i. At this time, as described above, the corresponding stack pointer is incremented by one.

If the value of MM1 [i] .size is 0 (S160), since the data region of the packet index i is completely released, the entire packet may be released. In order to release the corresponding packet, the MM2 [i] .sp is initialized to 0, the MM3.p is searched, and the pointers belonging to the i packet are deleted (S170).

In this case, in order to release the memory allocated by the memory manager 130, the memory manager 130 calculates the allocated main memory pointer p 'as shown in [Equation 2] and manages to allocate the memory to another memory allocation request. It may be (S180). After calculating the main memory pointer p ', the memory manager 130 permits the release request and terminates (S181).

[Equation 2]

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

For example, in the example of FIG. 2, after each layer that processes a packet is allocated memory of size1 + size2 + size3 from the memory manager 130, it is processed into three pieces of divided data of size1, size2, and size3. Can be. In this case, when partial release is performed on two pieces of data p1 and p2, SMM may be updated to a value of MM1 [i] .size = size3, and when p3 is released, MM1 [i] .size is 0 in S160. Since 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 allocating and releasing memory used for data transfer between protocol layers in a communication system or the like, each allocated memory is allocated to a predetermined size. In the case of using the partition, the data can be partially released, so that even if the data moving between the communication layers is divided, the memory copyless system can be configured smoothly, thereby improving the performance of the system.

As described above, the present invention has been described by specific embodiments such as specific components and the like, but the embodiments and the drawings are provided only to help a more general understanding of the present invention, and the present invention is not limited to the above embodiments. For those skilled in the art, various modifications and variations may be made without departing from the essential features of the present invention. Accordingly, the spirit of the present invention should not be limited to the described embodiments, and all technical ideas having equivalent or equivalent modifications to the claims as well as the following claims are included in the scope of the present invention. Should be interpreted as.

Packet Storage Memory 110
Release management memory (120)
Pointer Storage Memory (121)
Secondary Memory (122)
Memory manager (130)

Claims (9)

A memory management apparatus supporting partial release of memory allocation,
A packet storage memory for storing header information including data packet size and tag information and data of the data packet in a header and a data area separated by a packet index;
A release management memory for managing a pointer in which the allocation of the packet storage memory is partially released and the packet index; And
Storing and managing the header information and the data in the packet storage memory, and a release target pointer and a release target size according to the allocation release request of the packet storage memory, and whether the release target pointer exists in the release management memory. Accordingly, comprising a memory manager for determining a partial release of the packet storage memory,
The memory manager determines whether to release the packet storage memory by determining whether the tag information is in front of the release target pointer and whether the release target size coincides with the size of the data packet. Device. delete The method of claim 1,
When the partial release of the packet storage memory is determined, the memory manager checks whether the release target pointer exists in the release management memory or not, and if the partial release does not correspond to the deduplication, And a release target pointer in the release management memory. The method of claim 3,
If the partial release does not correspond to the deduplication, the memory manager updates the size of the data packet by subtracting the release target size from the size of the data packet, and the updated size of the data packet is 0. Otherwise, the release target pointer and the packet index corresponding to the release target pointer are stored in the release management memory. The method of claim 3,
The memory manager calculates the packet index (i) with respect to the release target pointer (p) using the following equation.
(Mathematical formula)
i = FLOOR ((p-BASE_ADDRESS) / (MM1_S + DATA_S))
Here, FLOOR (k) is a maximum integer value not greater than k, BASE_ADDRESS is a reference address of the packet storage memory, MM1_S is the size of the header, and DATA_S is the size of the data area. The method of claim 1,
The release management memory includes a pointer storage memory and an auxiliary memory for managing the partially released pointer and the packet index,
The memory manager stores the release target pointer in the storage corresponding to the packet index in the pointer storage memory, and when the stack pointer corresponding to the packet index reaches the preset maximum value in the pointer storage memory, the release is performed. And a packet index corresponding to a target pointer and the release target pointer in a storage divided by a stack pointer of the auxiliary memory. In the memory management method for supporting partial release of memory allocation in the memory management device,
Storing header information including a size of a data packet and tag information in a header of a packet storage memory;
Storing data of the data packet in a data area of the packet storage memory;
Determining a partial release of the packet storage memory based on a release target pointer and a release target size according to the de-allocation request of the packet storage memory;
When the partial release of the packet storage memory is determined, redundancy release for the partial release is determined depending on whether the release target pointer exists in the release management memory for managing the pointer and the packet index in which the allocation of the packet storage memory is partially released. Checking whether there is; And
If the partial release does not correspond to the deduplication, storing the release target pointer and the packet index corresponding to the release target pointer in the release management memory;
The determining may include determining whether the packet storage memory is partially released by determining whether the tag information is in front of the tag information and whether the size of the packet is identical to the size of the data packet. How to manage. delete The method of claim 7, wherein
If the partial release does not correspond to the deduplication, updating the size of the data packet by subtracting the release target size from the size of the data packet; And
And storing the release target pointer and the packet index corresponding to the release target pointer in the release management memory when the updated size of the data packet is not equal to zero.

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