tools/perf/tests/dlfilter-test.c

Source file repositories/reference/linux-study-clean/tools/perf/tests/dlfilter-test.c

File Facts

System
Linux kernel
Corpus path
tools/perf/tests/dlfilter-test.c
Extension
.c
Size
10376 bytes
Lines
442
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: implementation source
Status
source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

struct test_data {
	struct perf_tool tool;
	struct machine *machine;
	int fd;
	u64 foo;
	u64 bar;
	u64 ip;
	u64 addr;
	char name[DLFILTER_TEST_NAME_MAX];
	char desc[DLFILTER_TEST_NAME_MAX];
	char perf[PATH_MAX];
	char perf_data_file_name[PATH_MAX];
	char c_file_name[PATH_MAX];
	char prog_file_name[PATH_MAX];
	char dlfilters[PATH_MAX];
};

static int test_result(const char *msg, int ret)
{
	pr_debug("%s\n", msg);
	return ret;
}

static int process(const struct perf_tool *tool, union perf_event *event,
		   struct perf_sample *sample __maybe_unused,
		   struct machine *machine __maybe_unused)
{
	struct test_data *td = container_of(tool, struct test_data, tool);
	int fd = td->fd;

	if (writen(fd, event, event->header.size) != event->header.size)
		return -1;

	return 0;
}

#define MAXCMD 4096
#define REDIRECT_TO_DEV_NULL " >/dev/null 2>&1"

static __printf(1, 2) int system_cmd(const char *fmt, ...)
{
	char cmd[MAXCMD + sizeof(REDIRECT_TO_DEV_NULL)];
	int ret;

	va_list args;

	va_start(args, fmt);
	ret = vsnprintf(cmd, MAXCMD, fmt, args);
	va_end(args);

	if (ret <= 0 || ret >= MAXCMD)
		return -1;

	if (verbose <= 0)
		strcat(cmd, REDIRECT_TO_DEV_NULL);

	pr_debug("Command: %s\n", cmd);
	ret = system(cmd);
	if (ret)
		pr_debug("Failed with return value %d\n", ret);

	return ret;
}

static bool have_gcc(void)
{
	pr_debug("Checking for gcc\n");
	return !system_cmd("gcc --version");
}

static int write_attr(struct test_data *td, u64 sample_type, u64 *id)
{
	struct perf_event_attr attr = {
		.size = sizeof(attr),
		.type = PERF_TYPE_HARDWARE,
		.config = PERF_COUNT_HW_BRANCH_INSTRUCTIONS,
		.sample_type = sample_type,
		.sample_period = 1,
	};

	return perf_event__synthesize_attr(&td->tool, &attr, 1, id, process);
}

static int write_comm(int fd, pid_t pid, pid_t tid, const char *comm_str)
{
	struct perf_record_comm comm;
	ssize_t sz = sizeof(comm);

	comm.header.type = PERF_RECORD_COMM;
	comm.header.misc = PERF_RECORD_MISC_USER;

Annotation

Implementation Notes