Buddy Allocation using Linked Lists

This is a sample implementation for the buddy memory allocation algorithm using linked lists.
It is build in the context of the HPI Embedded Operating Systems lecture 2017.

Building

Run make.

Running the example

Provide the wanted memory pool size in KB as first parameter.

# e.g. 2048 KB
buddy 2048

Example Output

The example allocates and deallocates memory in the following order:
+ 120 KB
+ 128 KB
+ 40 KB
+ 356 KB
+ 359 KB
- 359 KB
- 356 KB
- 40 KB
- 128 KB
- 120 KB

After each allocation or deallocation the state of all free-lists is printed. An entry in a free-list ist the start address of a free block in that list.

BUDDY SYSTEM ALLOCATION
Memory size: 2048 kB
Min block size: 64 kB
Memory begins at: 0x109f16000
Memory status:
64:
128:
256:
512:
1024:
2048: 0x109f16000

request: 120
[1] start addres: 0x109f16000
64:
128: 0x109f35400
256: 0x109f54800
512: 0x109f93000
1024: 0x10a010000
2048:

request: 128
[2] start addres: 0x109f35400
64:
128:
256: 0x109f54800
512: 0x109f93000
1024: 0x10a010000
2048:

request: 40
[3] start addres: 0x109f54800
64: 0x109f64200
128: 0x109f73c00
256:
512: 0x109f93000
1024: 0x10a010000
2048:

request: 356
[4] start addres: 0x109f93000
64: 0x109f64200
128: 0x109f73c00
256:
512:
1024: 0x10a010000
2048:

request: 359
[5] start addres: 0x10a010000
64: 0x109f64200
128: 0x109f73c00
256:
512: 0x10a08d000
1024:
2048:

free [5]: 512KB
64: 0x109f64200
128: 0x109f73c00
256:
512:
1024: 0x10a010000
2048:

free [4]: 512KB
64: 0x109f64200
128: 0x109f73c00
256:
512: 0x109f93000
1024: 0x10a010000
2048:

free [3]: 64KB
64:
128:
256: 0x109f54800
512: 0x109f93000
1024: 0x10a010000
2048:


free [2]: 128KB
64:
128: 0x109f35400
256: 0x109f54800
512: 0x109f93000
1024: 0x10a010000
2048:

free [1]: 128KB
64:
128:
256:
512:
1024:
2048: 0x109f16000