kernel/range.c

Source file repositories/reference/linux-study-clean/kernel/range.c

File Facts

System
Linux kernel
Corpus path
kernel/range.c
Extension
.c
Size
3110 bytes
Lines
166
Domain
Core OS
Bucket
Scheduler, Processes, Timers, Sync, And Syscalls
Inferred role
Core OS: implementation source
Status
source implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

Dependency Surface

Detected Declarations

Annotated Snippet

if (start <= range[j].start && end >= range[j].end) {
			range[j].start = 0;
			range[j].end = 0;
			continue;
		}

		if (start <= range[j].start && end < range[j].end &&
		    range[j].start < end) {
			range[j].start = end;
			continue;
		}


		if (start > range[j].start && end >= range[j].end &&
		    range[j].end > start) {
			range[j].end = start;
			continue;
		}

		if (start > range[j].start && end < range[j].end) {
			/* Find the new spare: */
			for (i = 0; i < az; i++) {
				if (range[i].end == 0)
					break;
			}
			if (i < az) {
				range[i].end = range[j].end;
				range[i].start = end;
			} else {
				pr_err("%s: run out of slot in ranges\n",
					__func__);
			}
			range[j].end = start;
			continue;
		}
	}
}

static int cmp_range(const void *x1, const void *x2)
{
	const struct range *r1 = x1;
	const struct range *r2 = x2;

	if (r1->start < r2->start)
		return -1;
	if (r1->start > r2->start)
		return 1;
	return 0;
}

int clean_sort_range(struct range *range, int az)
{
	int i, j, k = az - 1, nr_range = az;

	for (i = 0; i < k; i++) {
		if (range[i].end)
			continue;
		for (j = k; j > i; j--) {
			if (range[j].end) {
				k = j;
				break;
			}
		}
		if (j == i)
			break;
		range[i].start = range[k].start;
		range[i].end   = range[k].end;
		range[k].start = 0;
		range[k].end   = 0;
		k--;
	}
	/* count it */
	for (i = 0; i < az; i++) {
		if (!range[i].end) {
			nr_range = i;
			break;
		}
	}

	/* sort them */
	sort(range, nr_range, sizeof(struct range), cmp_range, NULL);

	return nr_range;
}

void sort_range(struct range *range, int nr_range)
{
	/* sort them */
	sort(range, nr_range, sizeof(struct range), cmp_range, NULL);
}

Annotation

Implementation Notes