Merge tag 'perf-core-for-mingo-20161125' of git://git.kernel.org/pub/…

…scm/linux/kernel/git/acme/linux into perf/core

Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:

New features:

- Improve ARM support in the annotation code, affecting 'perf annotate', 'perf
  report' and live annotation in 'perf top' (Kim Phillips)

- Initial support for PowerPC in the annotation code (Ravi Bangoria)

- Skip repetitive scheduler function on the top of the stack in
  'perf sched timehist' (Namhyung Kim)

Fixes:

- Fix maps resolution in libbpf (Eric Leblond)

- Get the kernel signature via /proc/version_signature, available on
  Ubuntu systems, to make sure BPF proggies works, as the one provided
  via 'uname -r' doesn't (Wang Nan)

- Fix segfault in 'perf record' when running with suid and kptr_restrict
  is 1 (Wang Nan)

Infrastructure changes:

- Support per-arch instruction tables, kept via a static or dynamic table
  (Arnaldo Carvalho de Melo)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

tools/lib/bpf/libbpf.c

@@ -185,6 +185,7 @@ struct bpf_program {
 struct bpf_map {
 	int fd;
 	char *name;
+	size_t offset;
 	struct bpf_map_def def;
 	void *priv;
 	bpf_map_clear_priv_t clear_priv;
@@ -513,57 +514,106 @@ bpf_object__init_kversion(struct bpf_object *obj,
 }
 
 static int
-bpf_object__init_maps(struct bpf_object *obj, void *data,
-		      size_t size)
+bpf_object__validate_maps(struct bpf_object *obj)
 {
-	size_t nr_maps;
 	int i;
 
-	nr_maps = size / sizeof(struct bpf_map_def);
-	if (!data || !nr_maps) {
-		pr_debug("%s doesn't need map definition\n",
-			 obj->path);
+	/*
+	 * If there's only 1 map, the only error case should have been
+	 * catched in bpf_object__init_maps().
+	 */
+	if (!obj->maps || !obj->nr_maps || (obj->nr_maps == 1))
 		return 0;
-	}
 
-	pr_debug("maps in %s: %zd bytes\n", obj->path, size);
+	for (i = 1; i < obj->nr_maps; i++) {
+		const struct bpf_map *a = &obj->maps[i - 1];
+		const struct bpf_map *b = &obj->maps[i];
 
-	obj->maps = calloc(nr_maps, sizeof(obj->maps[0]));
-	if (!obj->maps) {
-		pr_warning("alloc maps for object failed\n");
-		return -ENOMEM;
+		if (b->offset - a->offset < sizeof(struct bpf_map_def)) {
+			pr_warning("corrupted map section in %s: map \"%s\" too small\n",
+				   obj->path, a->name);
+			return -EINVAL;
+		}
 	}
-	obj->nr_maps = nr_maps;
-
-	for (i = 0; i < nr_maps; i++) {
-		struct bpf_map_def *def = &obj->maps[i].def;
+	return 0;
+}
 
-		/*
-		 * fill all fd with -1 so won't close incorrect
-		 * fd (fd=0 is stdin) when failure (zclose won't close
-		 * negative fd)).
-		 */
-		obj->maps[i].fd = -1;
+static int compare_bpf_map(const void *_a, const void *_b)
+{
+	const struct bpf_map *a = _a;
+	const struct bpf_map *b = _b;
 
-		/* Save map definition into obj->maps */
-		*def = ((struct bpf_map_def *)data)[i];
-	}
-	return 0;
+	return a->offset - b->offset;
 }
 
 static int
-bpf_object__init_maps_name(struct bpf_object *obj)
+bpf_object__init_maps(struct bpf_object *obj)
 {
-	int i;
+	int i, map_idx, nr_maps = 0;
+	Elf_Scn *scn;
+	Elf_Data *data;
 	Elf_Data *symbols = obj->efile.symbols;
 
-	if (!symbols || obj->efile.maps_shndx < 0)
+	if (obj->efile.maps_shndx < 0)
+		return -EINVAL;
+	if (!symbols)
+		return -EINVAL;
+
+	scn = elf_getscn(obj->efile.elf, obj->efile.maps_shndx);
+	if (scn)
+		data = elf_getdata(scn, NULL);
+	if (!scn || !data) {
+		pr_warning("failed to get Elf_Data from map section %d\n",
+			   obj->efile.maps_shndx);
 		return -EINVAL;
+	}
 
+	/*
+	 * Count number of maps. Each map has a name.
+	 * Array of maps is not supported: only the first element is
+	 * considered.
+	 *
+	 * TODO: Detect array of map and report error.
+	 */
 	for (i = 0; i < symbols->d_size / sizeof(GElf_Sym); i++) {
 		GElf_Sym sym;
-		size_t map_idx;
+
+		if (!gelf_getsym(symbols, i, &sym))
+			continue;
+		if (sym.st_shndx != obj->efile.maps_shndx)
+			continue;
+		nr_maps++;
+	}
+
+	/* Alloc obj->maps and fill nr_maps. */
+	pr_debug("maps in %s: %d maps in %zd bytes\n", obj->path,
+		 nr_maps, data->d_size);
+
+	if (!nr_maps)
+		return 0;
+
+	obj->maps = calloc(nr_maps, sizeof(obj->maps[0]));
+	if (!obj->maps) {
+		pr_warning("alloc maps for object failed\n");
+		return -ENOMEM;
+	}
+	obj->nr_maps = nr_maps;
+
+	/*
+	 * fill all fd with -1 so won't close incorrect
+	 * fd (fd=0 is stdin) when failure (zclose won't close
+	 * negative fd)).
+	 */
+	for (i = 0; i < nr_maps; i++)
+		obj->maps[i].fd = -1;
+
+	/*
+	 * Fill obj->maps using data in "maps" section.
+	 */
+	for (i = 0, map_idx = 0; i < symbols->d_size / sizeof(GElf_Sym); i++) {
+		GElf_Sym sym;
 		const char *map_name;
+		struct bpf_map_def *def;
 
 		if (!gelf_getsym(symbols, i, &sym))
 			continue;
@@ -573,21 +623,27 @@ bpf_object__init_maps_name(struct bpf_object *obj)
 		map_name = elf_strptr(obj->efile.elf,
 				      obj->efile.strtabidx,
 				      sym.st_name);
-		map_idx = sym.st_value / sizeof(struct bpf_map_def);
-		if (map_idx >= obj->nr_maps) {
-			pr_warning("index of map \"%s\" is buggy: %zu > %zu\n",
-				   map_name, map_idx, obj->nr_maps);
-			continue;
+		obj->maps[map_idx].offset = sym.st_value;
+		if (sym.st_value + sizeof(struct bpf_map_def) > data->d_size) {
+			pr_warning("corrupted maps section in %s: last map \"%s\" too small\n",
+				   obj->path, map_name);
+			return -EINVAL;
 		}
+
 		obj->maps[map_idx].name = strdup(map_name);
 		if (!obj->maps[map_idx].name) {
 			pr_warning("failed to alloc map name\n");
 			return -ENOMEM;
 		}
-		pr_debug("map %zu is \"%s\"\n", map_idx,
+		pr_debug("map %d is \"%s\"\n", map_idx,
 			 obj->maps[map_idx].name);
+		def = (struct bpf_map_def *)(data->d_buf + sym.st_value);
+		obj->maps[map_idx].def = *def;
+		map_idx++;
 	}
-	return 0;
+
+	qsort(obj->maps, obj->nr_maps, sizeof(obj->maps[0]), compare_bpf_map);
+	return bpf_object__validate_maps(obj);
 }
 
 static int bpf_object__elf_collect(struct bpf_object *obj)
@@ -645,11 +701,9 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
 			err = bpf_object__init_kversion(obj,
 							data->d_buf,
 							data->d_size);
-		else if (strcmp(name, "maps") == 0) {
-			err = bpf_object__init_maps(obj, data->d_buf,
-						    data->d_size);
+		else if (strcmp(name, "maps") == 0)
 			obj->efile.maps_shndx = idx;
-		} else if (sh.sh_type == SHT_SYMTAB) {
+		else if (sh.sh_type == SHT_SYMTAB) {
 			if (obj->efile.symbols) {
 				pr_warning("bpf: multiple SYMTAB in %s\n",
 					   obj->path);
@@ -698,7 +752,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
 		return LIBBPF_ERRNO__FORMAT;
 	}
 	if (obj->efile.maps_shndx >= 0)
-		err = bpf_object__init_maps_name(obj);
+		err = bpf_object__init_maps(obj);
 out:
 	return err;
 }
@@ -807,7 +861,7 @@ bpf_object__create_maps(struct bpf_object *obj)
 				zclose(obj->maps[j].fd);
 			return err;
 		}
-		pr_debug("create map: fd=%d\n", *pfd);
+		pr_debug("create map %s: fd=%d\n", obj->maps[i].name, *pfd);
 	}
 
 	return 0;

tools/perf/arch/arm/annotate/instructions.c

@@ -1,90 +1,59 @@
-static struct ins arm__instructions[] = {
-	{ .name = "add",	.ops = &mov_ops,  },
-	{ .name = "addl",	.ops = &mov_ops,  },
-	{ .name = "addq",	.ops = &mov_ops,  },
-	{ .name = "addw",	.ops = &mov_ops,  },
-	{ .name = "and",	.ops = &mov_ops,  },
-	{ .name = "b",		.ops = &jump_ops, }, // might also be a call
-	{ .name = "bcc",	.ops = &jump_ops, },
-	{ .name = "bcs",	.ops = &jump_ops, },
-	{ .name = "beq",	.ops = &jump_ops, },
-	{ .name = "bge",	.ops = &jump_ops, },
-	{ .name = "bgt",	.ops = &jump_ops, },
-	{ .name = "bhi",	.ops = &jump_ops, },
-	{ .name = "bl",		.ops = &call_ops, },
-	{ .name = "bls",	.ops = &jump_ops, },
-	{ .name = "blt",	.ops = &jump_ops, },
-	{ .name = "blx",	.ops = &call_ops, },
-	{ .name = "bne",	.ops = &jump_ops, },
-	{ .name = "bts",	.ops = &mov_ops,  },
-	{ .name = "call",	.ops = &call_ops, },
-	{ .name = "callq",	.ops = &call_ops, },
-	{ .name = "cmp",	.ops = &mov_ops,  },
-	{ .name = "cmpb",	.ops = &mov_ops,  },
-	{ .name = "cmpl",	.ops = &mov_ops,  },
-	{ .name = "cmpq",	.ops = &mov_ops,  },
-	{ .name = "cmpw",	.ops = &mov_ops,  },
-	{ .name = "cmpxch",	.ops = &mov_ops,  },
-	{ .name = "dec",	.ops = &dec_ops,  },
-	{ .name = "decl",	.ops = &dec_ops,  },
-	{ .name = "imul",	.ops = &mov_ops,  },
-	{ .name = "inc",	.ops = &dec_ops,  },
-	{ .name = "incl",	.ops = &dec_ops,  },
-	{ .name = "ja",		.ops = &jump_ops, },
-	{ .name = "jae",	.ops = &jump_ops, },
-	{ .name = "jb",		.ops = &jump_ops, },
-	{ .name = "jbe",	.ops = &jump_ops, },
-	{ .name = "jc",		.ops = &jump_ops, },
-	{ .name = "jcxz",	.ops = &jump_ops, },
-	{ .name = "je",		.ops = &jump_ops, },
-	{ .name = "jecxz",	.ops = &jump_ops, },
-	{ .name = "jg",		.ops = &jump_ops, },
-	{ .name = "jge",	.ops = &jump_ops, },
-	{ .name = "jl",		.ops = &jump_ops, },
-	{ .name = "jle",	.ops = &jump_ops, },
-	{ .name = "jmp",	.ops = &jump_ops, },
-	{ .name = "jmpq",	.ops = &jump_ops, },
-	{ .name = "jna",	.ops = &jump_ops, },
-	{ .name = "jnae",	.ops = &jump_ops, },
-	{ .name = "jnb",	.ops = &jump_ops, },
-	{ .name = "jnbe",	.ops = &jump_ops, },
-	{ .name = "jnc",	.ops = &jump_ops, },
-	{ .name = "jne",	.ops = &jump_ops, },
-	{ .name = "jng",	.ops = &jump_ops, },
-	{ .name = "jnge",	.ops = &jump_ops, },
-	{ .name = "jnl",	.ops = &jump_ops, },
-	{ .name = "jnle",	.ops = &jump_ops, },
-	{ .name = "jno",	.ops = &jump_ops, },
-	{ .name = "jnp",	.ops = &jump_ops, },
-	{ .name = "jns",	.ops = &jump_ops, },
-	{ .name = "jnz",	.ops = &jump_ops, },
-	{ .name = "jo",		.ops = &jump_ops, },
-	{ .name = "jp",		.ops = &jump_ops, },
-	{ .name = "jpe",	.ops = &jump_ops, },
-	{ .name = "jpo",	.ops = &jump_ops, },
-	{ .name = "jrcxz",	.ops = &jump_ops, },
-	{ .name = "js",		.ops = &jump_ops, },
-	{ .name = "jz",		.ops = &jump_ops, },
-	{ .name = "lea",	.ops = &mov_ops,  },
-	{ .name = "lock",	.ops = &lock_ops, },
-	{ .name = "mov",	.ops = &mov_ops,  },
-	{ .name = "movb",	.ops = &mov_ops,  },
-	{ .name = "movdqa",	.ops = &mov_ops,  },
-	{ .name = "movl",	.ops = &mov_ops,  },
-	{ .name = "movq",	.ops = &mov_ops,  },
-	{ .name = "movslq",	.ops = &mov_ops,  },
-	{ .name = "movzbl",	.ops = &mov_ops,  },
-	{ .name = "movzwl",	.ops = &mov_ops,  },
-	{ .name = "nop",	.ops = &nop_ops,  },
-	{ .name = "nopl",	.ops = &nop_ops,  },
-	{ .name = "nopw",	.ops = &nop_ops,  },
-	{ .name = "or",		.ops = &mov_ops,  },
-	{ .name = "orl",	.ops = &mov_ops,  },
-	{ .name = "test",	.ops = &mov_ops,  },
-	{ .name = "testb",	.ops = &mov_ops,  },
-	{ .name = "testl",	.ops = &mov_ops,  },
-	{ .name = "xadd",	.ops = &mov_ops,  },
-	{ .name = "xbeginl",	.ops = &jump_ops, },
-	{ .name = "xbeginq",	.ops = &jump_ops, },
-	{ .name = "retq",	.ops = &ret_ops,  },
+#include <sys/types.h>
+#include <regex.h>
+
+struct arm_annotate {
+	regex_t call_insn,
+		jump_insn;
 };
+
+static struct ins_ops *arm__associate_instruction_ops(struct arch *arch, const char *name)
+{
+	struct arm_annotate *arm = arch->priv;
+	struct ins_ops *ops;
+	regmatch_t match[2];
+
+	if (!regexec(&arm->call_insn, name, 2, match, 0))
+		ops = &call_ops;
+	else if (!regexec(&arm->jump_insn, name, 2, match, 0))
+		ops = &jump_ops;
+	else
+		return NULL;
+
+	arch__associate_ins_ops(arch, name, ops);
+	return ops;
+}
+
+static int arm__annotate_init(struct arch *arch)
+{
+	struct arm_annotate *arm;
+	int err;
+
+	if (arch->initialized)
+		return 0;
+
+	arm = zalloc(sizeof(*arm));
+	if (!arm)
+		return -1;
+
+#define ARM_CONDS "(cc|cs|eq|ge|gt|hi|le|ls|lt|mi|ne|pl|vc|vs)"
+	err = regcomp(&arm->call_insn, "^blx?" ARM_CONDS "?$", REG_EXTENDED);
+	if (err)
+		goto out_free_arm;
+	err = regcomp(&arm->jump_insn, "^bx?" ARM_CONDS "?$", REG_EXTENDED);
+	if (err)
+		goto out_free_call;
+#undef ARM_CONDS
+
+	arch->initialized = true;
+	arch->priv	  = arm;
+	arch->associate_instruction_ops   = arm__associate_instruction_ops;
+	arch->objdump.comment_char	  = ';';
+	arch->objdump.skip_functions_char = '+';
+	return 0;
+
+out_free_call:
+	regfree(&arm->call_insn);
+out_free_arm:
+	free(arm);
+	return -1;
+}