CN1984025B - Method and store-and-forward device for releasing invalidly occupied resources - Google Patents

Abstract

The invention relates to a method for releasing invalid occupied resources and a store-and-forward device, the core of which is that: when detecting that no data message is sent on the output port, starting a timer set corresponding to the output port to start timing; and when the timing time of the timer reaches a timing period, releasing the resources occupied by the invalidation. By the invention, when the output port works abnormally, the distributed resources can be released in time, and the participation of a CPU and the operation of software are not needed.

Description

Method and store-and-forward device for releasing invalidly occupied resources

technical field

The present invention relates to the communication field, in particular to store and forward technology. the

Background technique

The "store-and-forward" structure shown in Figure 1 is usually used in the data communication chip, which includes a receiving management module, a buffer module for message data, a forwarding processing module and a sending management module. The receiving management module includes at least one receiving port, and the sending management module includes at least one output port, and an output queue corresponding to the output port. the

When performing data communication, the receiving management module receives the message data completely through each receiving port, and then applies for the corresponding cache resource to the message data cache module, if the corresponding cache resource cannot be applied for, it will receive The received message data is discarded; if the corresponding cache resource can be applied for, the receiving management module will obtain the storage address for storing the received message data, and store the received data in the report according to the storage address In the text data cache module, at the same time, the storage address and part of the message data (including the "destination address" information and the "source address" information at the head of the message data, etc.) are used as forwarding processing information and sent to the A forwarding processing module; the forwarding processing module analyzes and processes the forwarding processing information, and determines the forwarding information of the message data according to the analysis result, including whether the message data needs to be discarded, or which output port to forward to, etc. After the forwarding processing module obtains the forwarding information of the message data, it will write the storage address information corresponding to the message data into the "first in first out" output queue corresponding to each output port according to the forwarding information, Then wait to send. The sending management module reads the address information in the output queue according to the output data of the output port, and reads the address information from the message data cache module according to the address information The message data corresponding to the address is read from the computer, and then sent out through the corresponding output port. the

After the message data is output from the output port, the chip releases the cache resources and queue resources occupied by the message data. the

In the above process, when the chip analyzes and processes the forwarding and processing information of the current data message, the receiving port may receive some subsequent data messages, and the chip must allocate some cache resources to store the message data; However, these storage resources and queue resources cannot be recovered and reused until the packet data is sent out from the output port. In addition, when the chip is working, sometimes some output ports will be interrupted suddenly, such as network cable disconnection, sudden power failure, and the user does not shut down the connected network device according to the prescribed procedures. There are some cache or queue resources assigned to the output port. If these ports cannot return to normal in time, these allocated cache or queue resources will be occupied for a long time and cannot be used by other ports, thus affecting the performance of the chip. make an impact. Therefore, it is necessary to check the working status of the output port frequently, so as to judge the connection status of the link in time, and when the link is interrupted, the allocated buffer or queue resources can be released in time. the

The prior art related to the present invention provides a method for releasing allocated cache or queue resources, the main idea of which is:

The sending management module constantly checks the circuit connection signal on the output port, that is, the Link signal to know the connection status of the link of the output port, and actively reports the detected information to the CPU; when the CPU knows the output according to the reported information After the link of the port is interrupted, control the sending management module to continuously discard the data packets sent to the output port from the corresponding queue and buffer until the CPU learns that the link of the output port is restored, then stop This discarding process restores the normal sending of data packets. the

The prior art 1 requires the CPU to perform processing, thereby increasing the burden on the CPU. the

The prior art 2 related to the present invention provides another method for releasing allocated cache or queue resources, the main idea of which is:

Regularly and continuously check whether the output port is sending data (especially data packets of some protocol types) through the high-level software, and judge whether the link is always online according to the detected information; when the link interruption occurs at the output port , continuously discard the data packets sent to the output port from the corresponding queue and cache, so as to realize the recovery of occupied resources. Once the link of the port is re-checked and the connection is restored, the discarding process is stopped and the normal sending of data packets is resumed. the

The second prior art requires high-level software for processing, which will cause software running overhead and increase the burden on the CPU running the software. the

Contents of the invention

The purpose of the present invention is to provide a method for releasing invalidly occupied resources and a store-and-forward device. Through the present invention, when the output port works abnormally in the prior art, the CPU needs to be involved in order to realize the recovery of occupied resources. , or the need to run high-level software for processing and other drawbacks. the

The purpose of the present invention is achieved by the following technical solutions:

The present invention provides a method for releasing invalidly occupied resources, which includes:

A. When it is detected that there is no data message sent on the output port, the timer set corresponding to the output port is started to start counting;

B. When the counting time of the timer reaches the timing period, release the invalidly occupied data resources. the

Wherein, the timing period of the timer is longer than the time required for sending each data packet during normal output. the

Wherein, the step A specifically includes:

The sending management module detects whether there is a data message sent on each output port set therein, and when it detects that there is no data message sent on a certain output port, it starts the timer set corresponding to the output port and starts counting ;

or,

The sending management module detects whether there is a data packet sent on each output port outside it. and when it is detected that there is no data message sent on a certain output port, the timer set corresponding to the output port starts counting. the

Wherein, in said step B specifically include:

B1. Before the timing time of the timer reaches the timing period, continue to detect whether there is a data message sent on the output port normally, and when it is detected that the data message is sent on the output port, then send all The timer is reset, and stop counting, and then continue to step A; when it is detected that there is no data message sent on the output port, then perform step B2;

B2. When the timing time of the timer reaches the timing period, read the storage address in the output queue corresponding to the output port, and read the corresponding storage address from the message data cache module according to the storage address Address message data, and then discard it, and release the queue resource corresponding to the storage address and the cache resource corresponding to the message data; at the same time, reset the timer, and then turn to step A. the

The present invention provides a storage and forwarding device, which includes at least one output port, wherein each output port also includes a timer, which is used to start counting when no data message is sent from the output port, and when the counting time reaches When the timing period expires, the store-and-forward device is triggered to release invalidly occupied data resources. the

Wherein, the timing period of the timer is longer than the time required for sending each data packet during normal output. the

Wherein, the timer is located inside the output port, or located outside the output port. the

Wherein, the store-and-forward device also includes:

The sending management module is used to detect whether the output port has a data message to send, and when there is no data message to send, the sending signal triggers the timer; and when the timing time of the timer reaches the timing period, the release is invalidly occupied data resources. the

Among them, the invalidly occupied data resources include:

In the output queue that has been assigned to the output port but cannot be sent within the timing period of the timer queue resources; and correspond to message resources cached in the message data cache module. the

Wherein, the output port is located inside the sending management module, or located outside the sending management module, and connected to the sending management module. the

As can be seen from the technical solution provided by the above-mentioned present invention, in the present invention, when it is detected that there is no data message to send on a certain output port, start the timer set corresponding to the output port and start counting; and when the timing When the timing time of the timer reaches the timing period, the resources that are invalidly occupied are released. Therefore, when the output port works abnormally, the present invention can not only release allocated resources in time, but also does not require the participation of the CPU and the operation of software. the

Description of drawings

Fig. 1 is the working principle diagram of the chip of "store-and-forward" structure provided in the background technology;

Fig. 2 is the flowchart of the first embodiment provided by the present invention;

Fig. 3 is the schematic diagram of the second embodiment provided by the present invention;

Fig. 4 is a schematic diagram of the store-and-forward device when the output port is set outside the sending management module and each timer is set in the sending management module and corresponds to each output port in the third embodiment provided by the present invention. the

Detailed ways

For a data communication chip with a "store-and-forward" structure, when the link of some output ports is suddenly interrupted during its operation (such as disconnection of the network cable, sudden power failure, and the user does not follow the prescribed procedures to go offline, etc.), this When there are already some buffer resources or queue resources allocated to the output port in the chip, these resources are called invalidly occupied resources, if these resources are released in time, the limited resources can be fully utilized, and if without CPU involvement or It is more ideal that the participation of high-level software can release the invalidly occupied resources in time. the

The present invention provides a first embodiment, which is a method for timely releasing invalidly occupied resources without the participation of CPU or high-level software. Its core is to set a timer corresponding to each output port, and when the sending management When the module detects that there is no data message sent on a certain output port, it starts the timer on the corresponding output port to start counting. When the counting time of the timer reaches the timing period, the sending management module releases the invalidly occupied resources. Its specific implementation process is shown in Figure 2, including the following steps:

Step 1: Set a timer corresponding to each output port, and set the timing period of the timer to be longer than the time required for sending each data message during normal output. the

The timer starts counting only when there is no data message to be sent on the corresponding output port, and when the corresponding output port has a data message to output normally, the timer is in the reset state and will not perform timing processing . the

The timing period of the timer can be set to different values to adapt to different working conditions. the

Step 2, the sending management module detects whether there is a data message to be sent on each output port, and when it is detected that there is no data message to be sent on a certain output port, then perform step 3, that is, start the timer set on the output port The timer starts timing, and then performs step 5; when it is detected that each output port has a data message to send, then perform step 4, that is, put the timer in a reset state, and then continue with step 2. the

Step 5, before the timing time of the timer reaches the timing period, continue to detect whether there is a data message sent on the output port normally, when the sending management module detects that there is a data message sent on the output port , then execute step 6, that is, reset the timer, stop timing, and then continue to step 2; when it is detected that no data message is sent on the output port, then execute step 7. the

Step 7, when the timing time of the timer reaches the timing period, the sending management module reads the storage address information in the output queue corresponding to the output port, and according to the storage location The address information reads the message data corresponding to the storage address from the message data cache module, and then discards it, releasing the queue resource corresponding to the storage address information and the cache resource corresponding to the message data. At the same time, reset the timer, and then go to step 2. the

Once the link of the output port is interrupted, the data message cannot be sent on the output port for a long time, and the timer on the output port can reach the specified timing period at this time. the

The second embodiment provided by the present invention is a store-and-forward device, the working principle of which is shown in Figure 3, including:

A receiving management module, a message data cache module, a forwarding processing module, and a sending management module; wherein the receiving management module includes at least one receiving port, and the sending management module includes at least one output port, an output queue corresponding to the output port, and A timer set on each output port; the timing period of the timer is greater than the time required for sending each data message during normal output. the

When performing data communication, the receiving management module receives the message data completely through the receiving ports, and then applies to the message data cache module for corresponding cache resources, if the corresponding cache resources cannot be applied for , the received message data is discarded; if the corresponding cache resource can be applied for, the receiving management module will obtain the storage address for storing the received message data, and will receive the received message data according to the storage address The data is stored in the message data cache module, and at the same time, the storage address and part of the content information in the message data (including the "destination address" information and "source address" information at the head of the message data, etc.) are used as The forwarding processing information is sent to the forwarding processing module. the

The forwarding processing module analyzes and processes the forwarding processing information, and determines the forwarding information of the message data according to the analysis result, including whether the message data needs to be discarded, or which output port to forward to, etc. After the forwarding processing module obtains the forwarding information of the message data, the storage address corresponding to the message data will be written into the corresponding output port in the sending management module according to the forwarding information "First in, first out" output queue, and then waiting to be sent. the

The sending management module detects whether a data message is sent on the output port, and when it detects that a data message is sent normally on the output port, it continuously reads the storage address in the output queue corresponding to the output port , and read the message data corresponding to the storage address from the message data cache module according to the storage address, and then send it out through the output port. the

When the sending management module detects that there is no data message to send on the output port, then start the timer set on the output port to start counting; if the timing time of the timer does not reach the timing period before, And when the sending management module detects that there is a data message to be sent on the output port, the sending management module resets the timer and stops timing. If no data message is sent on the output port before the timing time of the timer reaches the timing period, the timing time of the timer will reach the timing period, and the timer will trigger the The sending management module releases resources that are invalidly occupied: that is to say, the sending management module reads the storage address in the output queue corresponding to the output port, and reads from the message data cache module according to the storage address The message data corresponding to the storage address is discarded, and the queue resource corresponding to the storage address and the cache resource corresponding to the message data are released. Then, the timer is reset, and timing is restarted, so that it goes round and round, and whenever the timing time of the timer reaches its timing period, a data message is discarded, and corresponding cache and queue resources are released. When the sending management module detects that there is a data packet to be sent on the port, it stops discarding. the

In the above embodiment, the timer may not be set on each output port, but set in the sending management module independently of each output port, but at this time, each timer still needs to correspond to each output port. the

The third embodiment provided by the present invention is another store-and-forward device, which is different from the second embodiment in that the output port is set outside the sending management module and connected to the sending management module. At this time, each timer can be set in the sending management module, and is connected with each output port should be; each timer can also be set on each corresponding output port. As shown in FIG. 4 , a schematic diagram of the store-and-forward device is provided when the output port is set outside the sending management module, and each timer is set in the sending management module and corresponds to each output port. the

The information transfer process between each module and the timer in the third embodiment is basically similar to that in the second embodiment, and will not be described in detail here. the

As can be seen from the specific embodiments of the present invention described above, when detecting that there is no data message sent on a certain output port in the present invention, start the timer set corresponding to the output port and start counting; and when the timer When the timing time reaches the timing period, the resources that are invalidly occupied are released. Therefore, when the output port works abnormally, the present invention can not only release allocated resources in time, but also does not require the participation of the CPU and the operation of software. the

The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed in the present invention can easily think of changes or Replacement should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims. the

Claims (7)

1. A method for releasing invalidly occupied resources, comprising: A, when detecting that there is no data message to send on the output port, then start the timer that is set corresponding to the output port and start counting; B. When the timing time of the timer reaches the timing period, release the invalidly occupied data resource; Wherein, the step B includes: B1. Before the timing time of the timer reaches the timing period, continue to detect whether there is a data message sent on the output port normally, and when it is detected that the data message is sent on the output port, then send all The timer is reset, and stop counting, and then continue to step A; when it is detected that there is no data message sent on the output port, then perform step B2; B2. When the timing time of the timer reaches the timing period, read the storage address in the output queue corresponding to the output port, and read the corresponding storage address from the message data cache module according to the storage address Address message data, and then discard it, and release the queue resource corresponding to the storage address and the cache resource corresponding to the message data; at the same time, reset the timer, and then turn to step A. 2. The method according to claim 1, characterized in that: The timing period of the timer is longer than the time required for sending each data message during normal output. 3. The method according to claim 1 or 2, wherein said step A specifically comprises: The sending management module detects whether there is a data message sent on each output port set therein, and when it detects that there is no data message sent on a certain output port, it starts the timer set corresponding to the output port and starts counting ; or, The sending management module detects whether there is a data message sent on each output port set outside it, and when it detects that there is no data message sent on a certain output port, the timer set corresponding to the output port starts counting. 4. A storage and forwarding device, comprising at least one output port, is characterized in that, corresponding to each output port also includes a timer, for when the output port does not have a data message to send, then start timing, and when the timing When the timing period is reached, the store-and-forward device is triggered to release invalidly occupied data resources; Also includes: a sending management module, used to detect whether the output port has a data message to send, when there is no data message to send, send a signal to trigger the timer; and when the timing time of the timer reaches the timing period, release The queue resources in the output queue that have been allocated to the output port but cannot be sent within the timing period of the timer, and the corresponding message resources buffered in the message data buffer module. 5. The store and forward device according to claim 4, characterized in that: The timing period of the timer is longer than the time required for sending each data message during normal output. 6. The store and forward device according to claim 4, characterized in that: The timer is internal to the output port, or external to the output port. 7. The store and forward device according to claim 4, characterized in that: The output port is located inside or outside the sending management module and connected to the sending management module.

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