JP3419392B2 - Memory access monitoring device, memory access monitoring method, and recording medium recording memory access monitoring program - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a memory access monitoring device, a memory access monitoring method, and a recording medium having a memory access monitoring program recorded therein, and in particular, analysis of causes when a shared memory is destroyed in a multiprocessor system. The present invention relates to a memory access monitoring device, a memory access monitoring method, and a recording medium recording a memory access monitoring program.

[0002]

2. Description of the Related Art In a multiprocessor system, a plurality of CPUs and a plurality of input / output devices access a shared memory. Therefore, if any CPU or I / O device makes an illegal memory access, the entire multiprocessor system becomes a failure.

Therefore, in the conventional technique, a debug device is attached to each CPU and a log is collected to collect information for investigating the cause of the illegal memory access.

[0004]

However, according to the conventional technique, when analyzing the cause in the case where the contents of the shared memory are destroyed due to an illegal memory access, when analyzing the cause of the damage to the CPU and the shared memory, the contents of the shared memory are destroyed. The CPU that detected that the contents of the shared memory were corrupted because the CPU that detected that the contents were corrupted might be different.
Since it is not enough to investigate the logs collected by the CPU, it is difficult to analyze the cause, that is, the logs collected by each CPU must be aggregated and all the aggregated logs must be investigated. .

It is an object of the present invention to provide a memory access monitoring device which facilitates cause analysis when a shared memory is destroyed in a multiprocessor system.

[0006]

A first memory access monitoring device of the present invention is a multiprocessor system having a shared memory, a plurality of CPUs, and a plurality of input / output devices, and an access request to the shared memory. Means for receiving from the plurality of CPUs or the plurality of input / output devices, and generating an interrupt if the access request is an access request made without acquiring a spinlock,
A means for outputting that there is an access request made without acquiring a spinlock, or a means for outputting a log indicating that there is an access request made without acquiring a spinlock Is characterized by.

A second memory access monitoring device of the present invention is a multiprocessor system having a shared memory, a plurality of CPUs, and a plurality of input / output devices, and requests access to the shared memory to the plurality of CPUs or Receiving means for receiving from the plurality of input / output devices; address comparing means for determining whether the access request is an access request for a specific area in the shared memory;
Memory access means for accessing the shared memory;
An interrupt unit for generating an interrupt, a log output unit for outputting a log, a reception unit for executing an access request to the shared memory, and an address comparison unit for executing the access request in a specific area. If it is not an access request for a specific area, the memory access unit is executed to access the shared memory, and if it is an access request for a specific area, It is determined whether a spin lock has been acquired. When the spin lock is acquired, the memory access unit is executed to access the shared memory. When the spin lock is not acquired, the interrupt unit is executed. Or access executed without executing the log output means to generate an interrupt and acquire a spinlock Characterized by comprising a monitoring control means for outputting a log indicating that determined is whether to output the there was that, or spin lock there is an access request made without getting.

According to a third memory access monitoring apparatus of the present invention, in the second memory access monitoring apparatus, a receiving means for receiving a request for acquiring a spin lock and a spin lock and writing to a lock variable. When a request for acquiring the spinlock by receiving the request by executing the receiving means, the spinlock means for storing the embedded value in the spinlock data register, and the monitoring control means,
When the spinlock means is executed to perform spinlock, the value written in the lock variable is stored in the spinlock data register, and the receiving means is executed to receive an access request to the shared memory. Is to determine whether or not the spin lock has been acquired by referring to the spin lock data register.

According to a first memory access monitoring method of the present invention, in a multiprocessor system having a shared memory, a plurality of CPUs, and a plurality of input / output devices, an access request to the shared memory is transmitted to the plurality of CPUs. If the access request received from the plurality of input / output devices is an access request made without acquiring a spinlock, an access is generated and an access made without acquiring a spinlock. It is characterized in that a request is output, or a log indicating that there is an access request made without acquiring a spinlock is output.

According to a second memory access monitoring method of the present invention, in a multiprocessor system having a shared memory, a plurality of CPUs, and a plurality of input / output devices, an access request to the shared memory is received and received. If the access request is not an access request for a specific area, the shared memory is accessed, and if the access request is for a specific area, it is determined whether a spinlock has been acquired, and a spinlock is performed. When the shared memory has been acquired, the shared memory is accessed, and when the spinlock is not acquired, an interrupt is generated and the fact that there is an access request made without acquiring the spinlock is output, or It is characterized by outputting a log indicating that there is an access request made without acquiring a spinlock.

According to a third memory access monitoring method of the present invention, in a multiprocessor system having a shared memory, a plurality of CPUs, and a plurality of input / output devices, a request for acquiring a spinlock is received, and a spin is acquired. When the lock is acquired, the value written in the lock variable is stored in the spinlock data register, the access request to the shared memory is received, and when the received access request is not the access request to the specific area, When the shared memory is accessed and an access request to a specific area is made, it is determined whether or not the spin lock has been acquired by referring to the spin lock data register, and when the spin lock has been acquired. Accesses the shared memory and has not acquired the spinlock,
Generate an interrupt and output that there was an access request that was made without acquiring a spinlock, or output a log that shows that there was an access request that was made without acquiring a spinlock. Is characterized by.

According to a first recording medium of the present invention, in a multiprocessor system having a shared memory, a plurality of CPUs, and a plurality of input / output devices, an access request to the shared memory is issued to the plurality of CPUs or the plurality of CPUs. If the received access request is an access request made without acquiring the spinlock, an interrupt is generated, and the access request made without acquiring the spinlock is It is characterized by recording a program for causing a computer to execute a process of outputting a log indicating that there is an access request made without acquiring a spinlock.

A second recording medium of the present invention is a multiprocessor system having a shared memory, a plurality of CPUs, and a plurality of input / output devices, receiving an access request to the shared memory, and receiving the received access. If the request is not an access request to a specific area, the shared memory is accessed. If the request is an access request to the specific area, it is determined whether or not a spin lock has been acquired, and a spin lock is acquired. If it has already been accessed, the shared memory is accessed, and if the spin lock is not acquired, an interrupt is generated and the fact that there is an access request made without acquiring the spin lock is output.
Alternatively, it is characterized by recording a program for causing a computer to execute a process of outputting a log indicating that an access request is made without acquiring a spinlock.

A third recording medium of the present invention receives a request for acquiring a spinlock in a multiprocessor system having a shared memory, a plurality of CPUs, and a plurality of input / output devices, and locks the spinlock. The value written in the lock variable is stored in the spin lock data register while being acquired, and when the access request to the shared memory is received and the received access request is not the access request to the specific area, the sharing is performed. When accessing the memory and requesting access to a specific area,
The spin lock data register is referenced to determine whether or not a spin lock has been acquired.When the spin lock is acquired, the shared memory is accessed, and when the spin lock is not acquired, an interrupt is generated. The computer performs a process of generating and outputting a log indicating that there is an access request made without acquiring a spinlock, or outputting a log indicating that there is an access request made without acquiring a spinlock. It is characterized by recording the program to be executed by.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail with reference to the drawings.

First, the first embodiment of the present invention will be described in detail.

Referring to FIG. 1, according to a first embodiment of the present invention, a shared memory 200, a memory access monitoring device 100 connected to the shared memory 200, and a plurality of CPUs.
300, a plurality of input / output devices 400, and a bus 500 connecting these to each other.

Further, referring to FIG. 2, the memory access monitoring device 200 includes a monitoring control means 110 and a receiving means 1.
11, spin lock means 112, memory access means 113, address comparison means 114, interrupt means 115, log output means 116, buffer 120,
Monitor flag register 130, spinlock address register 140, spinlock data register 150
And a monitoring area start address register 160, a monitoring area end address register 170, and a log area 180. The monitoring flag register 130 includes a spin lock flag 131, a write flag 132, and an interrupt flag 133. In addition, the memory access monitoring device 200 operates under program control.

The buffer 120 stores a memory access request or a spinlock request from the CPU 300 or the input / output device 400.

The spin lock flag 131 is set to ON when it is desired to monitor a memory access request made without acquiring a spin lock. Specified by the user by the debugger.

The write flag 132 is turned on when it is desired to monitor only the write request among the memory access requests. Specified by the user by the debugger.

The interrupt flag 133 turns ON when an interrupt is generated. Specified by the user by the debugger.

The spin lock address register 140 stores a memory address of a lock variable necessary to acquire a spin lock. Specified by the user by the debugger.

The spinlock data register 150 includes
Zero is stored when the spin lock is not acquired, and a non-zero value is stored when the spin lock is acquired.

The monitoring area start address register 160 stores the start position of the memory address of the specific area when the specific area of the shared memory 200 is to be monitored. Specified by the user by the debugger.

The monitoring area end address register 170 stores the end position of the memory address of the specific area when the specific area of the shared memory 200 is to be monitored. Specified by the user by the debugger.

The log area 180 serves as a log storage location.

The monitor control means 110 is provided with the receiving means 111.
, Spin lock means 112, and memory access means 1
13, address comparison means 114, and interrupt means 11
5. Control the log output means 116.

The receiving means 111 receives a memory access request to the shared memory 200 from the CPU 300 or the input / output device 400 and stores it in the buffer 120.

The spin lock means 112 reads the value of the spin lock (lock variable, writes a value other than zero if the value of the lock variable is zero, and reads it until it reaches zero if it is not zero. Repeat)
The value written in the lock variable is stored in the spin lock data register 150.

The memory access unit 113 uses the shared memory 200 at the memory address included in the memory access request.
To access.

The address comparison means 114 includes the buffer 12
The memory address included in the memory access request stored in 0, and the spinlock address register 140,
The memory addresses stored in the monitoring area start address register 160 and the monitoring area end address register 170 are compared.

The interrupt means 115 generates an interrupt to notify that there is an access request made without acquiring the spinlock.

The log output means 116 outputs a log indicating that there is an access request made without acquiring a spinlock in the log area 180.

Next, the overall operation of the present embodiment will be described in detail with reference to FIGS.

First, the user sets values to the spin lock flag 131, the write flag 132, the interrupt flag 133, the spin lock address register 140, the spin lock data register 150, the monitoring area start address register 160, and the monitoring area end address register 170 by the debugger. Set.

Specifically, the spin lock flag 131 is set to ON to monitor only memory access requests made without acquiring spin locks, and all memory access requests are acquired regardless of acquisition of spin locks. When monitoring is set to OFF.

The write flag 132 is set to ON when monitoring only the write request among the memory access requests, and is set to OF when monitoring all the memory access requests.
Set F.

The interrupt flag 133 is set to ON when an interrupt is generated, and is set to OFF when an interrupt is not generated.

In the spin lock address register 140, the memory address of the lock variable required to acquire the spin lock is set.

In the monitoring area start address register 160, the starting position of the memory address of the specific area to be monitored in the shared memory 200 is set, and in the monitoring area end address register 170, the ending position is set.

When the user debugs the program, the monitor control means 110 of the memory access monitoring device 100 causes the CPU 300 or the input / output device 40 to operate.
The memory access request from 0 is received by the receiving means 111 and stored in the buffer 120 (step S1).

Next, the monitor control means 110 compares the memory address included in the memory access request with the address stored in the spinlock address register 140 by the address comparison means 114 (step S2).

As a result of the comparison, if they match, that is, if they are equal to the memory address of the lock variable, the value written in the lock variable by the spin lock is stored in the spin lock data register 150 (steps S12 and S1).
3) If they do not match, the monitoring control means 110 causes the address comparison means 114 to check the memory address included in the memory access request and the monitoring area start address register 1
60 and the address stored in the monitoring area end address register 170 are compared (step S3).

As a result of the comparison, if the memory address included in the memory access request is within the range of the monitoring area,
It is determined that it is necessary to monitor the access in the monitoring area in the shared memory 200, and the following processing (step S4 to
After performing step S10), the memory access means 113
By this, the shared memory 200 is accessed at the memory address (step S11), and if it is outside the range of the monitoring area, it is determined that it is not necessary to monitor the access in the monitoring area in the shared memory 200, and the following is shown. The shared memory 200 is executed at the memory address by the memory access unit 113 without executing the processes (steps S4 to S10).
Is accessed (step S11).

Next, the monitoring control means 110, step S
For those judged to be monitored by the check of 3,
Referring to the spin lock flag 131 (step S4),
When the spin lock flag 131 is ON, access to the shared memory 200 that has not acquired the spin lock is a monitoring target, and therefore the spin lock data register 150
(Step S8), and when the content is zero,
Even if the spin lock is not acquired, the target is to be monitored because it is in the state of trying to access the shared memory 200, and if it is not zero, the spin lock is being acquired. Therefore, the shared memory 200 is normally accessed by the memory access unit 113 (step S11). On the other hand, when the spin lock flag 131 is OFF, the access to the shared memory 200 is monitored regardless of whether the spin lock is acquired.

Further, the monitoring control means 110, the step S
4 and the write flag 132 that is determined to be monitored by the check in step S8 (step S5). If the write flag 132 is ON, only the write request is monitored in the access to the shared memory 200. Since it is a target, it is checked whether or not it is a write request by referring to the memory access request stored in the buffer 120 (step S9). If it is a write request, it is a monitoring target, and if it is not a write, it is a monitoring target. Therefore, the shared memory 200 is normally accessed by the memory access unit 113 (step S11). On the other hand, when the write flag 132 is OFF, the shared memory 200
It is a monitoring target regardless of whether or not the access request to the is a write request.

Further, the monitoring control means 110 refers to the interrupt flag 133 for the objects which are judged to be monitored by the checks in step S5 and step S9 (step S6), and when the interrupt flag 133 is ON, interrupts. Is generated to output that there was an access request made without acquiring the spinlock, and when the interrupt flag 133 is OFF, there was an access request made without acquiring the spinlock. A log indicating that is output to the log area 180 (step S10), and the shared memory 200 is accessed by the memory access unit 113 (step S11).

Next, a second embodiment of the present invention will be described with reference to the drawings.

Referring to FIG. 4, the second embodiment of the present invention comprises a recording medium 600 recording a memory access monitoring program. The recording medium 600 may be a floppy (registered trademark) disk, a magnetic disk, a semiconductor memory, or another recording medium. The memory access monitoring program is read from the recording medium 600 and controls the operation of the memory access monitoring device 100. The memory access monitoring device 100 executes the above-described processing, that is, the same processing as the processing in the first embodiment, under the control of the memory access monitoring program.

[0051]

As described above, according to the memory access monitoring apparatus of the present invention, an interrupt is generated at the time of memory access without spinlock, that is, at the time when the contents of the memory may be destroyed. It is possible to perform the cause analysis easily.
Has the effect of.

Further, since the logs can be investigated without being aggregated, there is a second effect that the cause analysis can be easily performed.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a first exemplary embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a first exemplary embodiment of the present invention.

FIG. 3 is a flowchart showing the operation of the first exemplary embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of a second exemplary embodiment of the present invention.

[Explanation of symbols]

100 memory access monitoring device 110 Monitoring and control means 111 receiving means 112 Spin Lock Means 113 Memory Access Means 114 address comparison means 115 interruption means 116 Log output means 120 buffers 130 Monitoring flag register 131 Spinlock flag 132 Light flag 133 interrupt flag 140 Spinlock Address Register 150 Spinlock Data Register 160 Monitoring area start address register 170 Monitoring area end register 180 log area 200 shared memory 300 CPU 400 I / O device 500 bus 600 recording media

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Claims (9)

(57) [Claims] 1. A multiprocessor system having a shared memory, a plurality of CPUs, and a plurality of input / output devices, and means for receiving an access request to the shared memory from the plurality of CPUs or the plurality of input / output devices. And, if the access request is an access request made without acquiring a spinlock, an interrupt is generated and the fact that there is an access request made without acquiring a spinlock is output, Or a means for outputting a log indicating that there is an access request made without acquiring a spinlock. 2. A multiprocessor system having a shared memory, a plurality of CPUs, and a plurality of input / output devices, wherein a reception request for accessing the shared memory is received from the plurality of CPUs or the plurality of input / output devices. An address comparing unit that determines whether the access request is an access request to a specific area in the shared memory; a memory access unit that accesses the shared memory; an interrupt unit that generates an interrupt; Log output means for outputting a log; and executing the receiving means to receive an access request to the shared memory and executing the address comparison means to determine whether the access request is an access request to a specific area. If it is not an access request for a specific area, the memory access means is executed. The shared memory is accessed by the access point, and if the access request is for a specific area, it is determined whether the spin lock has been acquired. If the spin lock has been acquired, the memory access unit is executed. Then, the shared memory is accessed, and when the spinlock is not acquired, the interrupt means or the log output means is executed to generate an interrupt, and there is an access request made without acquiring the spinlock. Or a monitor control unit that outputs a log indicating that there is an access request made without acquiring a spin lock. 3. Receiving means for receiving a request for acquiring a spin lock, spin lock means for acquiring a spin lock and storing the value written in a lock variable in a spin lock data register, and the monitor control. When the means executes the receiving means and receives a request for acquiring a spinlock, the means executes the spinlock means to spinlock and writes the value written in the lock variable into the spinlock data register. When the access request to the shared memory is received by executing the receiving means, the spin lock data register is referred to and it is determined whether or not the spin lock is acquired. The memory access monitoring device according to claim 2, wherein the memory access monitoring device is a memory access monitoring device. 4. A multiprocessor system having a shared memory, a plurality of CPUs, and a plurality of input / output devices, wherein an access request to the shared memory is received from the plurality of CPUs or the plurality of input / output devices, When the received access request is an access request made without acquiring a spinlock, an interrupt is generated and the fact that there is an access request made without acquiring a spinlock is output. Alternatively, a memory access monitoring method, which outputs a log indicating that an access request has been made without acquiring a spinlock. 5. In a multiprocessor system having a shared memory, a plurality of CPUs, and a plurality of input / output devices, an access request to the shared memory is received, and the received access request is an access request to a specific area. If not, access the shared memory,
If it is an access request to a specific area, it is determined whether a spin lock has been acquired. If the spin lock has been acquired, the shared memory is accessed, and if the spin lock has not been acquired. , Generate an interrupt, and output that there was an access request that was made without acquiring the spinlock, or output a log that shows that there was an access request that was made without acquiring the spinlock. A memory access monitoring method characterized by the above. 6. In a multiprocessor system having a shared memory, a plurality of CPUs, and a plurality of input / output devices, a request for acquiring a spinlock is received, the spinlock is acquired, and a lock variable is written. Store the embedded value in a spinlock data register, receive an access request to the shared memory, and if the received access request is not an access request to a specific area, access the shared memory,
When the access request is for a specific area, it is determined whether or not the spin lock is acquired by referring to the spin lock data register. When the spin lock is acquired, the shared memory is accessed. However, when the spinlock is not acquired, an interrupt is generated and the fact that there is an access request made without acquiring the spinlock is output, or an access request made without acquiring the spinlock is output. A memory access monitoring method characterized by outputting a log indicating that there is. 7. A multiprocessor system having a shared memory, a plurality of CPUs, and a plurality of input / output devices, wherein an access request to the shared memory is received from the plurality of CPUs or the plurality of input / output devices, When the received access request is an access request made without acquiring a spinlock, an interrupt is generated and the fact that there is an access request made without acquiring a spinlock is output. Alternatively, a recording medium having recorded therein a program for causing a computer to execute a process of outputting a log indicating that there is an access request made without acquiring a spinlock. 8. A multiprocessor system having a shared memory, a plurality of CPUs, and a plurality of input / output devices, wherein an access request to the shared memory is received, and the received access request is an access request to a specific area. If not, access the shared memory,
If it is an access request to a specific area, it is determined whether a spin lock has been acquired. If the spin lock has been acquired, the shared memory is accessed, and if the spin lock has not been acquired. , Generate an interrupt, and output that there was an access request that was made without acquiring the spinlock, or output a log that shows that there was an access request that was made without acquiring the spinlock. A recording medium having recorded therein a program for causing a computer to execute a process. 9. In a multiprocessor system having a shared memory, a plurality of CPUs, and a plurality of input / output devices, a request for acquiring a spinlock is received, the spinlock is acquired, and a lock variable is written. Store the embedded value in a spinlock data register, receive an access request to the shared memory, and if the received access request is not an access request to a specific area, access the shared memory,
When the access request is for a specific area, it is determined whether or not the spin lock is acquired by referring to the spin lock data register. When the spin lock is acquired, the shared memory is accessed. However, when the spinlock is not acquired, an interrupt is generated and the fact that there is an access request made without acquiring the spinlock is output, or an access request made without acquiring the spinlock is output. A recording medium having recorded therein a program for causing a computer to execute a process of outputting a log indicating that there was.