arch/x86/kernel/cpu/debugfs.c

Source file repositories/reference/linux-study-clean/arch/x86/kernel/cpu/debugfs.c

File Facts

System
Linux kernel
Corpus path
arch/x86/kernel/cpu/debugfs.c
Extension
.c
Size
3269 bytes
Lines
102
Domain
Architecture Layer
Bucket
arch/x86
Inferred role
Architecture Layer: operation-table or driver-model contract
Status
pattern implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

static const struct file_operations dfs_cpu_ops = {
	.open		= cpu_debug_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

static int dom_debug_show(struct seq_file *m, void *p)
{
	static const char *domain_names[TOPO_MAX_DOMAIN] = {
		[TOPO_SMT_DOMAIN]	= "Thread",
		[TOPO_CORE_DOMAIN]	= "Core",
		[TOPO_MODULE_DOMAIN]	= "Module",
		[TOPO_TILE_DOMAIN]	= "Tile",
		[TOPO_DIE_DOMAIN]	= "Die",
		[TOPO_DIEGRP_DOMAIN]	= "DieGrp",
		[TOPO_PKG_DOMAIN]	= "Package",
	};
	unsigned int dom, nthreads = 1;

	for (dom = 0; dom < TOPO_MAX_DOMAIN; dom++) {
		nthreads *= x86_topo_system.dom_size[dom];
		seq_printf(m, "domain: %-10s shift: %u dom_size: %5u max_threads: %5u\n",
			   domain_names[dom], x86_topo_system.dom_shifts[dom],
			   x86_topo_system.dom_size[dom], nthreads);
	}
	return 0;
}

static int dom_debug_open(struct inode *inode, struct file *file)
{
	return single_open(file, dom_debug_show, inode->i_private);
}

static const struct file_operations dfs_dom_ops = {
	.open		= dom_debug_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

static __init int cpu_init_debugfs(void)
{
	struct dentry *dir, *base = debugfs_create_dir("topo", arch_debugfs_dir);
	unsigned long id;
	char name[24];

	debugfs_create_file("domains", 0444, base, NULL, &dfs_dom_ops);

	dir = debugfs_create_dir("cpus", base);
	for_each_possible_cpu(id) {
		sprintf(name, "%lu", id);
		debugfs_create_file(name, 0444, dir, (void *)id, &dfs_cpu_ops);
	}
	return 0;
}
late_initcall(cpu_init_debugfs);

Annotation

Implementation Notes