kernel/trace/trace_uprobe.c

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

File Facts

System
Linux kernel
Corpus path
kernel/trace/trace_uprobe.c
Extension
.c
Size
40278 bytes
Lines
1712
Domain
Core OS
Bucket
Scheduler, Processes, Timers, Sync, And Syscalls
Inferred role
Core OS: operation-table or driver-model contract
Status
pattern 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

static const struct file_operations uprobe_events_ops = {
	.owner		= THIS_MODULE,
	.open		= probes_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release,
	.write		= probes_write,
};

/* Probes profiling interfaces */
static int probes_profile_seq_show(struct seq_file *m, void *v)
{
	struct dyn_event *ev = v;
	struct trace_uprobe *tu;
	unsigned long nhits;
	int cpu;

	if (!is_trace_uprobe(ev))
		return 0;

	tu = to_trace_uprobe(ev);

	nhits = 0;
	for_each_possible_cpu(cpu) {
		nhits += per_cpu(*tu->nhits, cpu);
	}

	seq_printf(m, "  %s %-44s %15lu\n", tu->filename,
		   trace_probe_name(&tu->tp), nhits);
	return 0;
}

static const struct seq_operations profile_seq_op = {
	.start  = dyn_event_seq_start,
	.next   = dyn_event_seq_next,
	.stop   = dyn_event_seq_stop,
	.show	= probes_profile_seq_show
};

static int profile_open(struct inode *inode, struct file *file)
{
	int ret;

	ret = security_locked_down(LOCKDOWN_TRACEFS);
	if (ret)
		return ret;

	return seq_open(file, &profile_seq_op);
}

static const struct file_operations uprobe_profile_ops = {
	.owner		= THIS_MODULE,
	.open		= profile_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release,
};

struct uprobe_cpu_buffer {
	struct mutex mutex;
	void *buf;
	int dsize;
};
static struct uprobe_cpu_buffer __percpu *uprobe_cpu_buffer;
static int uprobe_buffer_refcnt;
#define MAX_UCB_BUFFER_SIZE PAGE_SIZE

static int uprobe_buffer_init(void)
{
	int cpu, err_cpu;

	uprobe_cpu_buffer = alloc_percpu(struct uprobe_cpu_buffer);
	if (uprobe_cpu_buffer == NULL)
		return -ENOMEM;

	for_each_possible_cpu(cpu) {
		struct page *p = alloc_pages_node(cpu_to_node(cpu),
						  GFP_KERNEL, 0);
		if (p == NULL) {
			err_cpu = cpu;
			goto err;
		}
		per_cpu_ptr(uprobe_cpu_buffer, cpu)->buf = page_address(p);
		mutex_init(&per_cpu_ptr(uprobe_cpu_buffer, cpu)->mutex);
	}

	return 0;

err:
	for_each_possible_cpu(cpu) {

Annotation

Implementation Notes