[linux-2.6-block.git] / tools / perf / tests / vmlinux-kallsyms.c

#include <linux/compiler.h>
#include <linux/rbtree.h>
#include <string.h>
#include "map.h"
#include "symbol.h"
#include "util.h"
#include "tests.h"
#include "debug.h"
#include "machine.h"

#define UM(x) kallsyms_map->unmap_ip(kallsyms_map, (x))

int test__vmlinux_matches_kallsyms(int subtest __maybe_unused)
{
	int err = -1;
	struct rb_node *nd;
	struct symbol *sym;
	struct map *kallsyms_map, *vmlinux_map, *map;
	struct machine kallsyms, vmlinux;
	enum map_type type = MAP__FUNCTION;
	struct maps *maps = &vmlinux.kmaps.maps[type];
	u64 mem_start, mem_end;
	bool header_printed;

	/*
	 * Step 1:
	 *
	 * Init the machines that will hold kernel, modules obtained from
	 * both vmlinux + .ko files and from /proc/kallsyms split by modules.
	 */
	machine__init(&kallsyms, "", HOST_KERNEL_ID);
	machine__init(&vmlinux, "", HOST_KERNEL_ID);

	/*
	 * Step 2:
	 *
	 * Create the kernel maps for kallsyms and the DSO where we will then
	 * load /proc/kallsyms. Also create the modules maps from /proc/modules
	 * and find the .ko files that match them in /lib/modules/`uname -r`/.
	 */
	if (machine__create_kernel_maps(&kallsyms) < 0) {
		pr_debug("machine__create_kernel_maps ");
		goto out;
	}

	/*
	 * Step 3:
	 *
	 * Load and split /proc/kallsyms into multiple maps, one per module.
	 * Do not use kcore, as this test was designed before kcore support
	 * and has parts that only make sense if using the non-kcore code.
	 * XXX: extend it to stress the kcorre code as well, hint: the list
	 * of modules extracted from /proc/kcore, in its current form, can't
	 * be compacted against the list of modules found in the "vmlinux"
	 * code and with the one got from /proc/modules from the "kallsyms" code.
	 */
	if (__machine__load_kallsyms(&kallsyms, "/proc/kallsyms", type, true) <= 0) {
		pr_debug("dso__load_kallsyms ");
		goto out;
	}

	/*
	 * Step 4:
	 *
	 * kallsyms will be internally on demand sorted by name so that we can
	 * find the reference relocation * symbol, i.e. the symbol we will use
	 * to see if the running kernel was relocated by checking if it has the
	 * same value in the vmlinux file we load.
	 */
	kallsyms_map = machine__kernel_map(&kallsyms);

	/*
	 * Step 5:
	 *
	 * Now repeat step 2, this time for the vmlinux file we'll auto-locate.
	 */
	if (machine__create_kernel_maps(&vmlinux) < 0) {
		pr_debug("machine__create_kernel_maps ");
		goto out;
	}

	vmlinux_map = machine__kernel_map(&vmlinux);

	/*
	 * Step 6:
	 *
	 * Locate a vmlinux file in the vmlinux path that has a buildid that
	 * matches the one of the running kernel.
	 *
	 * While doing that look if we find the ref reloc symbol, if we find it
	 * we'll have its ref_reloc_symbol.unrelocated_addr and then
	 * maps__reloc_vmlinux will notice and set proper ->[un]map_ip routines
	 * to fixup the symbols.
	 */
	if (machine__load_vmlinux_path(&vmlinux, type) <= 0) {
		pr_debug("Couldn't find a vmlinux that matches the kernel running on this machine, skipping test\n");
		err = TEST_SKIP;
		goto out;
	}

	err = 0;
	/*
	 * Step 7:
	 *
	 * Now look at the symbols in the vmlinux DSO and check if we find all of them
	 * in the kallsyms dso. For the ones that are in both, check its names and
	 * end addresses too.
	 */
	for (nd = rb_first(&vmlinux_map->dso->symbols[type]); nd; nd = rb_next(nd)) {
		struct symbol *pair, *first_pair;

		sym  = rb_entry(nd, struct symbol, rb_node);

		if (sym->start == sym->end)
			continue;

		mem_start = vmlinux_map->unmap_ip(vmlinux_map, sym->start);
		mem_end = vmlinux_map->unmap_ip(vmlinux_map, sym->end);

		first_pair = machine__find_kernel_symbol(&kallsyms, type,
							 mem_start, NULL);
		pair = first_pair;

		if (pair && UM(pair->start) == mem_start) {
next_pair:
			if (strcmp(sym->name, pair->name) == 0) {
				/*
				 * kallsyms don't have the symbol end, so we
				 * set that by using the next symbol start - 1,
				 * in some cases we get this up to a page
				 * wrong, trace_kmalloc when I was developing
				 * this code was one such example, 2106 bytes
				 * off the real size. More than that and we
				 * _really_ have a problem.
				 */
				s64 skew = mem_end - UM(pair->end);
				if (llabs(skew) >= page_size)
					pr_debug("WARN: %#" PRIx64 ": diff end addr for %s v: %#" PRIx64 " k: %#" PRIx64 "\n",
						 mem_start, sym->name, mem_end,
						 UM(pair->end));

				/*
				 * Do not count this as a failure, because we
				 * could really find a case where it's not
				 * possible to get proper function end from
				 * kallsyms.
				 */
				continue;
			} else {
				pair = machine__find_kernel_symbol_by_name(&kallsyms, type, sym->name, NULL);
				if (pair) {
					if (UM(pair->start) == mem_start)
						goto next_pair;

					pr_debug("WARN: %#" PRIx64 ": diff name v: %s k: %s\n",
						 mem_start, sym->name, pair->name);
				} else {
					pr_debug("WARN: %#" PRIx64 ": diff name v: %s k: %s\n",
						 mem_start, sym->name, first_pair->name);
				}

				continue;
			}
		} else
			pr_debug("ERR : %#" PRIx64 ": %s not on kallsyms\n",
				 mem_start, sym->name);

		err = -1;
	}

	if (!verbose)
		goto out;

	header_printed = false;

	for (map = maps__first(maps); map; map = map__next(map)) {
		struct map *
		/*
		 * If it is the kernel, kallsyms is always "[kernel.kallsyms]", while
		 * the kernel will have the path for the vmlinux file being used,
		 * so use the short name, less descriptive but the same ("[kernel]" in
		 * both cases.
		 */
		pair = map_groups__find_by_name(&kallsyms.kmaps, type,
						(map->dso->kernel ?
							map->dso->short_name :
							map->dso->name));
		if (pair) {
			pair->priv = 1;
		} else {
			if (!header_printed) {
				pr_info("WARN: Maps only in vmlinux:\n");
				header_printed = true;
			}
			map__fprintf(map, stderr);
		}
	}

	header_printed = false;

	for (map = maps__first(maps); map; map = map__next(map)) {
		struct map *pair;

		mem_start = vmlinux_map->unmap_ip(vmlinux_map, map->start);
		mem_end = vmlinux_map->unmap_ip(vmlinux_map, map->end);

		pair = map_groups__find(&kallsyms.kmaps, type, mem_start);
		if (pair == NULL || pair->priv)
			continue;

		if (pair->start == mem_start) {
			if (!header_printed) {
				pr_info("WARN: Maps in vmlinux with a different name in kallsyms:\n");
				header_printed = true;
			}

			pr_info("WARN: %" PRIx64 "-%" PRIx64 " %" PRIx64 " %s in kallsyms as",
				map->start, map->end, map->pgoff, map->dso->name);
			if (mem_end != pair->end)
				pr_info(":\nWARN: *%" PRIx64 "-%" PRIx64 " %" PRIx64,
					pair->start, pair->end, pair->pgoff);
			pr_info(" %s\n", pair->dso->name);
			pair->priv = 1;
		}
	}

	header_printed = false;

	maps = &kallsyms.kmaps.maps[type];

	for (map = maps__first(maps); map; map = map__next(map)) {
		if (!map->priv) {
			if (!header_printed) {
				pr_info("WARN: Maps only in kallsyms:\n");
				header_printed = true;
			}
			map__fprintf(map, stderr);
		}
	}
out:
	machine__exit(&kallsyms);
	machine__exit(&vmlinux);
	return err;
}
Commit	Line	Data
0a4e1ae6 JO	1	#include <linux/compiler.h>
	2	#include <linux/rbtree.h>
	3	#include <string.h>
	4	#include "map.h"
	5	#include "symbol.h"
	6	#include "util.h"
	7	#include "tests.h"
	8	#include "debug.h"
	9	#include "machine.h"
	10
82e75d00 AH	11	#define UM(x) kallsyms_map->unmap_ip(kallsyms_map, (x))
82e75d00 AH	12
721a1f53	13	int test__vmlinux_matches_kallsyms(int subtest __maybe_unused)
0a4e1ae6 JO	14	{
	15	int err = -1;
	16	struct rb_node *nd;
	17	struct symbol *sym;
4bb7123d	18	struct map kallsyms_map, vmlinux_map, *map;
0a4e1ae6 JO	19	struct machine kallsyms, vmlinux;
0a4e1ae6 JO	20	enum map_type type = MAP__FUNCTION;
1eee78ae	21	struct maps *maps = &vmlinux.kmaps.maps[type];
d380b348	22	u64 mem_start, mem_end;
54da0769	23	bool header_printed;
0a4e1ae6 JO	24
	25	/*
	26	* Step 1:
	27	*
	28	* Init the machines that will hold kernel, modules obtained from
	29	* both vmlinux + .ko files and from /proc/kallsyms split by modules.
	30	*/
	31	machine__init(&kallsyms, "", HOST_KERNEL_ID);
	32	machine__init(&vmlinux, "", HOST_KERNEL_ID);
	33
	34	/*
	35	* Step 2:
	36	*
	37	* Create the kernel maps for kallsyms and the DSO where we will then
	38	* load /proc/kallsyms. Also create the modules maps from /proc/modules
	39	* and find the .ko files that match them in /lib/modules/`uname -r`/.
	40	*/
	41	if (machine__create_kernel_maps(&kallsyms) < 0) {
	42	pr_debug("machine__create_kernel_maps ");
c0aab59f	43	goto out;
0a4e1ae6 JO	44	}
	45
	46	/*
	47	* Step 3:
	48	*
	49	* Load and split /proc/kallsyms into multiple maps, one per module.
53d0fe68 ACM	50	* Do not use kcore, as this test was designed before kcore support
	51	* and has parts that only make sense if using the non-kcore code.
	52	* XXX: extend it to stress the kcorre code as well, hint: the list
	53	* of modules extracted from /proc/kcore, in its current form, can't
	54	* be compacted against the list of modules found in the "vmlinux"
	55	* code and with the one got from /proc/modules from the "kallsyms" code.
0a4e1ae6	56	*/
be39db9f	57	if (__machine__load_kallsyms(&kallsyms, "/proc/kallsyms", type, true) <= 0) {
0a4e1ae6 JO	58	pr_debug("dso__load_kallsyms ");
	59	goto out;
	60	}
	61
	62	/*
	63	* Step 4:
	64	*
	65	* kallsyms will be internally on demand sorted by name so that we can
	66	* find the reference relocation * symbol, i.e. the symbol we will use
	67	* to see if the running kernel was relocated by checking if it has the
	68	* same value in the vmlinux file we load.
	69	*/
a5e813c6	70	kallsyms_map = machine__kernel_map(&kallsyms);
0a4e1ae6	71
0a4e1ae6 JO	72	/*
	73	* Step 5:
	74	*
	75	* Now repeat step 2, this time for the vmlinux file we'll auto-locate.
	76	*/
	77	if (machine__create_kernel_maps(&vmlinux) < 0) {
	78	pr_debug("machine__create_kernel_maps ");
	79	goto out;
	80	}
	81
a5e813c6	82	vmlinux_map = machine__kernel_map(&vmlinux);
0a4e1ae6 JO	83
	84	/*
	85	* Step 6:
	86	*
	87	* Locate a vmlinux file in the vmlinux path that has a buildid that
	88	* matches the one of the running kernel.
	89	*
	90	* While doing that look if we find the ref reloc symbol, if we find it
	91	* we'll have its ref_reloc_symbol.unrelocated_addr and then
	92	* maps__reloc_vmlinux will notice and set proper ->[un]map_ip routines
	93	* to fixup the symbols.
	94	*/
be39db9f	95	if (machine__load_vmlinux_path(&vmlinux, type) <= 0) {
531f67bb ACM	96	pr_debug("Couldn't find a vmlinux that matches the kernel running on this machine, skipping test\n");
531f67bb ACM	97	err = TEST_SKIP;
0a4e1ae6 JO	98	goto out;
	99	}
	100
	101	err = 0;
	102	/*
	103	* Step 7:
	104	*
	105	* Now look at the symbols in the vmlinux DSO and check if we find all of them
	106	* in the kallsyms dso. For the ones that are in both, check its names and
	107	* end addresses too.
	108	*/
	109	for (nd = rb_first(&vmlinux_map->dso->symbols[type]); nd; nd = rb_next(nd)) {
	110	struct symbol pair, first_pair;
0a4e1ae6 JO	111
	112	sym = rb_entry(nd, struct symbol, rb_node);
	113
	114	if (sym->start == sym->end)
	115	continue;
	116
d380b348 AH	117	mem_start = vmlinux_map->unmap_ip(vmlinux_map, sym->start);
	118	mem_end = vmlinux_map->unmap_ip(vmlinux_map, sym->end);
	119
	120	first_pair = machine__find_kernel_symbol(&kallsyms, type,
be39db9f	121	mem_start, NULL);
0a4e1ae6 JO	122	pair = first_pair;
0a4e1ae6 JO	123
82e75d00	124	if (pair && UM(pair->start) == mem_start) {
0a4e1ae6 JO	125	next_pair:
	126	if (strcmp(sym->name, pair->name) == 0) {
	127	/*
	128	* kallsyms don't have the symbol end, so we
	129	* set that by using the next symbol start - 1,
	130	* in some cases we get this up to a page
	131	* wrong, trace_kmalloc when I was developing
	132	* this code was one such example, 2106 bytes
	133	* off the real size. More than that and we
	134	* _really_ have a problem.
	135	*/
82e75d00	136	s64 skew = mem_end - UM(pair->end);
5888a8c2	137	if (llabs(skew) >= page_size)
e267769e	138	pr_debug("WARN: %#" PRIx64 ": diff end addr for %s v: %#" PRIx64 " k: %#" PRIx64 "\n",
d380b348	139	mem_start, sym->name, mem_end,
82e75d00	140	UM(pair->end));
5888a8c2 JO	141
	142	/*
	143	* Do not count this as a failure, because we
	144	* could really find a case where it's not
	145	* possible to get proper function end from
	146	* kallsyms.
	147	*/
	148	continue;
0a4e1ae6	149	} else {
be39db9f	150	pair = machine__find_kernel_symbol_by_name(&kallsyms, type, sym->name, NULL);
ab414dcd ACM	151	if (pair) {
ab414dcd ACM	152	if (UM(pair->start) == mem_start)
0a4e1ae6	153	goto next_pair;
0a4e1ae6	154
7e1b6595	155	pr_debug("WARN: %#" PRIx64 ": diff name v: %s k: %s\n",
ab414dcd	156	mem_start, sym->name, pair->name);
6566feaf	157	} else {
7e1b6595	158	pr_debug("WARN: %#" PRIx64 ": diff name v: %s k: %s\n",
6566feaf	159	mem_start, sym->name, first_pair->name);
0a4e1ae6	160	}
7e1b6595 ACM	161
7e1b6595 ACM	162	continue;
0a4e1ae6 JO	163	}
0a4e1ae6 JO	164	} else
e267769e	165	pr_debug("ERR : %#" PRIx64 ": %s not on kallsyms\n",
d380b348	166	mem_start, sym->name);
0a4e1ae6 JO	167
	168	err = -1;
	169	}
	170
	171	if (!verbose)
	172	goto out;
	173
54da0769	174	header_printed = false;
0a4e1ae6	175
4bb7123d ACM	176	for (map = maps__first(maps); map; map = map__next(map)) {
4bb7123d ACM	177	struct map *
0a4e1ae6 JO	178	/*
	179	* If it is the kernel, kallsyms is always "[kernel.kallsyms]", while
	180	* the kernel will have the path for the vmlinux file being used,
	181	* so use the short name, less descriptive but the same ("[kernel]" in
	182	* both cases.
	183	*/
	184	pair = map_groups__find_by_name(&kallsyms.kmaps, type,
4bb7123d ACM	185	(map->dso->kernel ?
	186	map->dso->short_name :
	187	map->dso->name));
54da0769	188	if (pair) {
0a4e1ae6	189	pair->priv = 1;
54da0769 ACM	190	} else {
	191	if (!header_printed) {
	192	pr_info("WARN: Maps only in vmlinux:\n");
	193	header_printed = true;
	194	}
4bb7123d	195	map__fprintf(map, stderr);
54da0769	196	}
0a4e1ae6 JO	197	}
0a4e1ae6 JO	198
54da0769	199	header_printed = false;
0a4e1ae6	200
4bb7123d ACM	201	for (map = maps__first(maps); map; map = map__next(map)) {
4bb7123d ACM	202	struct map *pair;
0a4e1ae6	203
4bb7123d ACM	204	mem_start = vmlinux_map->unmap_ip(vmlinux_map, map->start);
4bb7123d ACM	205	mem_end = vmlinux_map->unmap_ip(vmlinux_map, map->end);
d380b348 AH	206
d380b348 AH	207	pair = map_groups__find(&kallsyms.kmaps, type, mem_start);
0a4e1ae6 JO	208	if (pair == NULL \|\| pair->priv)
	209	continue;
	210
d380b348	211	if (pair->start == mem_start) {
54da0769 ACM	212	if (!header_printed) {
	213	pr_info("WARN: Maps in vmlinux with a different name in kallsyms:\n");
	214	header_printed = true;
	215	}
	216
e267769e	217	pr_info("WARN: %" PRIx64 "-%" PRIx64 " %" PRIx64 " %s in kallsyms as",
4bb7123d	218	map->start, map->end, map->pgoff, map->dso->name);
d380b348	219	if (mem_end != pair->end)
e267769e	220	pr_info(":\nWARN: *%" PRIx64 "-%" PRIx64 " %" PRIx64,
0a4e1ae6 JO	221	pair->start, pair->end, pair->pgoff);
	222	pr_info(" %s\n", pair->dso->name);
	223	pair->priv = 1;
	224	}
	225	}
	226
54da0769	227	header_printed = false;
0a4e1ae6	228
4bb7123d	229	maps = &kallsyms.kmaps.maps[type];
0a4e1ae6	230
4bb7123d	231	for (map = maps__first(maps); map; map = map__next(map)) {
54da0769 ACM	232	if (!map->priv) {
	233	if (!header_printed) {
	234	pr_info("WARN: Maps only in kallsyms:\n");
	235	header_printed = true;
	236	}
4bb7123d	237	map__fprintf(map, stderr);
54da0769	238	}
0a4e1ae6 JO	239	}
0a4e1ae6 JO	240	out:
c0aab59f ACM	241	machine__exit(&kallsyms);
c0aab59f ACM	242	machine__exit(&vmlinux);
0a4e1ae6 JO	243	return err;
0a4e1ae6 JO	244	}