tools/perf/util/dlfilter.c

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

File Facts

System
Linux kernel
Corpus path
tools/perf/util/dlfilter.c
Extension
.c
Size
14210 bytes
Lines
663
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

if (thread__maps(al->thread)) {
			struct machine *machine = maps__machine(thread__maps(al->thread));

			if (machine)
				perf_sample__fetch_insn(d->sample, al->thread, machine);
		}
	}

	if (!d->sample->insn_len)
		return NULL;

	*len = d->sample->insn_len;

	return (__u8 *)d->sample->insn;
}

static const char *dlfilter__srcline(void *ctx, __u32 *line_no)
{
	struct dlfilter *d = (struct dlfilter *)ctx;
	struct addr_location *al;
	unsigned int line = 0;
	char *srcfile = NULL;
	struct map *map;
	struct dso *dso;
	u64 addr;

	if (!d->ctx_valid || !line_no)
		return NULL;

	al = get_al(d);
	if (!al)
		return NULL;

	map = al->map;
	addr = al->addr;
	dso = map ? map__dso(map) : NULL;

	if (dso)
		srcfile = get_srcline_split(dso, map__rip_2objdump(map, addr), &line);

	*line_no = line;
	return srcfile;
}

static struct perf_event_attr *dlfilter__attr(void *ctx)
{
	struct dlfilter *d = (struct dlfilter *)ctx;

	if (!d->ctx_valid)
		return NULL;

	return &d->evsel->core.attr;
}

static __s32 code_read(__u64 ip, struct map *map, struct machine *machine, void *buf, __u32 len)
{
	u64 offset = map__map_ip(map, ip);

	if (ip + len >= map__end(map))
		len = map__end(map) - ip;

	return dso__data_read_offset(map__dso(map), machine, offset, buf, len);
}

static __s32 dlfilter__object_code(void *ctx, __u64 ip, void *buf, __u32 len)
{
	struct dlfilter *d = (struct dlfilter *)ctx;
	struct addr_location *al;
	struct addr_location a;
	__s32 ret;

	if (!d->ctx_valid)
		return -1;

	al = get_al(d);
	if (!al)
		return -1;

	if (al->map && ip >= map__start(al->map) && ip < map__end(al->map) &&
	    machine__kernel_ip(d->machine, ip) == machine__kernel_ip(d->machine, d->sample->ip))
		return code_read(ip, al->map, d->machine, buf, len);

	addr_location__init(&a);

	thread__find_map_fb(al->thread, d->sample->cpumode, ip, &a);
	ret = a.map ? code_read(ip, a.map, d->machine, buf, len) : -1;

	addr_location__exit(&a);

	return ret;

Annotation

Implementation Notes