Merge branch 'tracing/fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into tracing/urgent

11 files changed, 316 insertions, 64 deletions

diff --git a/tools/perf/util/cache.h b/tools/perf/util/cache.h
index 161d5f413e28..4b50c412b9c5 100644
--- a/tools/perf/util/cache.h
+++ b/tools/perf/util/cache.h
@@ -18,6 +18,7 @@
 #define PERFATTRIBUTES_FILE ".perfattributes"
 #define INFOATTRIBUTES_FILE "info/attributes"
 #define ATTRIBUTE_MACRO_PREFIX "[attr]"
+#define PERF_DEBUGFS_ENVIRONMENT "PERF_DEBUGFS_DIR"
 
 typedef int (*config_fn_t)(const char *, const char *, void *);
 extern int perf_default_config(const char *, const char *, void *);
diff --git a/tools/perf/util/header.h b/tools/perf/util/header.h
index b5ef53ad4c7a..bf280449fcfd 100644
--- a/tools/perf/util/header.h
+++ b/tools/perf/util/header.h
@@ -16,7 +16,7 @@ struct perf_header {
 	int frozen;
 	int attrs, size;
 	struct perf_header_attr **attr;
-	off_t attr_offset;
+	s64 attr_offset;
 	u64 data_offset;
 	u64 data_size;
 };
diff --git a/tools/perf/util/include/linux/kernel.h b/tools/perf/util/include/linux/kernel.h
index 99c1b3d1edd9..a6b87390cb52 100644
--- a/tools/perf/util/include/linux/kernel.h
+++ b/tools/perf/util/include/linux/kernel.h
@@ -18,4 +18,12 @@
 	(type *)((char *)__mptr - offsetof(type, member)); })
 #endif
 
+#ifndef max
+#define max(x, y) ({				\
+	typeof(x) _max1 = (x);			\
+	typeof(y) _max2 = (y);			\
+	(void) (&_max1 == &_max2);		\
+	_max1 > _max2 ? _max1 : _max2; })
+#endif
+
 #endif
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 5184959e0615..7bdad8df22a6 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -5,6 +5,7 @@
 #include "parse-events.h"
 #include "exec_cmd.h"
 #include "string.h"
+#include "cache.h"
 
 extern char *strcasestr(const char *haystack, const char *needle);
 
@@ -19,6 +20,8 @@ struct event_symbol {
 	char	*alias;
 };
 
+char debugfs_path[MAXPATHLEN];
+
 #define CHW(x) .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_##x
 #define CSW(x) .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_##x
 
@@ -71,8 +74,8 @@ static char *sw_event_names[] = {
 #define MAX_ALIASES 8
 
 static char *hw_cache[][MAX_ALIASES] = {
- { "L1-d$",	"l1-d",		"l1d",		"L1-data",		},
- { "L1-i$",	"l1-i",		"l1i",		"L1-instruction",	},
+ { "L1-dcache",	"l1-d",		"l1d",		"L1-data",		},
+ { "L1-icache",	"l1-i",		"l1i",		"L1-instruction",	},
  { "LLC",	"L2"							},
  { "dTLB",	"d-tlb",	"Data-TLB",				},
  { "iTLB",	"i-tlb",	"Instruction-TLB",			},
@@ -110,6 +113,88 @@ static unsigned long hw_cache_stat[C(MAX)] = {
  [C(BPU)]	= (CACHE_READ),
 };
 
+#define for_each_subsystem(sys_dir, sys_dirent, sys_next, file, st)	       \
+	while (!readdir_r(sys_dir, &sys_dirent, &sys_next) && sys_next)	       \
+	if (snprintf(file, MAXPATHLEN, "%s/%s", debugfs_path,	       	       \
+			sys_dirent.d_name) &&		       		       \
+	   (!stat(file, &st)) && (S_ISDIR(st.st_mode)) &&		       \
+	   (strcmp(sys_dirent.d_name, ".")) &&				       \
+	   (strcmp(sys_dirent.d_name, "..")))
+
+#define for_each_event(sys_dirent, evt_dir, evt_dirent, evt_next, file, st)    \
+	while (!readdir_r(evt_dir, &evt_dirent, &evt_next) && evt_next)        \
+	if (snprintf(file, MAXPATHLEN, "%s/%s/%s", debugfs_path,	       \
+		     sys_dirent.d_name, evt_dirent.d_name) &&		       \
+	   (!stat(file, &st)) && (S_ISDIR(st.st_mode)) &&		       \
+	   (strcmp(evt_dirent.d_name, ".")) &&				       \
+	   (strcmp(evt_dirent.d_name, "..")))
+
+#define MAX_EVENT_LENGTH 30
+
+int valid_debugfs_mount(const char *debugfs)
+{
+	struct statfs st_fs;
+
+	if (statfs(debugfs, &st_fs) < 0)
+		return -ENOENT;
+	else if (st_fs.f_type != (long) DEBUGFS_MAGIC)
+		return -ENOENT;
+	return 0;
+}
+
+static char *tracepoint_id_to_name(u64 config)
+{
+	static char tracepoint_name[2 * MAX_EVENT_LENGTH];
+	DIR *sys_dir, *evt_dir;
+	struct dirent *sys_next, *evt_next, sys_dirent, evt_dirent;
+	struct stat st;
+	char id_buf[4];
+	int fd;
+	u64 id;
+	char evt_path[MAXPATHLEN];
+
+	if (valid_debugfs_mount(debugfs_path))
+		return "unkown";
+
+	sys_dir = opendir(debugfs_path);
+	if (!sys_dir)
+		goto cleanup;
+
+	for_each_subsystem(sys_dir, sys_dirent, sys_next, evt_path, st) {
+		evt_dir = opendir(evt_path);
+		if (!evt_dir)
+			goto cleanup;
+		for_each_event(sys_dirent, evt_dir, evt_dirent, evt_next,
+								evt_path, st) {
+			snprintf(evt_path, MAXPATHLEN, "%s/%s/%s/id",
+				 debugfs_path, sys_dirent.d_name,
+				 evt_dirent.d_name);
+			fd = open(evt_path, O_RDONLY);
+			if (fd < 0)
+				continue;
+			if (read(fd, id_buf, sizeof(id_buf)) < 0) {
+				close(fd);
+				continue;
+			}
+			close(fd);
+			id = atoll(id_buf);
+			if (id == config) {
+				closedir(evt_dir);
+				closedir(sys_dir);
+				snprintf(tracepoint_name, 2 * MAX_EVENT_LENGTH,
+					"%s:%s", sys_dirent.d_name,
+					evt_dirent.d_name);
+				return tracepoint_name;
+			}
+		}
+		closedir(evt_dir);
+	}
+
+cleanup:
+	closedir(sys_dir);
+	return "unkown";
+}
+
 static int is_cache_op_valid(u8 cache_type, u8 cache_op)
 {
 	if (hw_cache_stat[cache_type] & COP(cache_op))
@@ -177,6 +262,9 @@ char *event_name(int counter)
 			return sw_event_names[config];
 		return "unknown-software";
 
+	case PERF_TYPE_TRACEPOINT:
+		return tracepoint_id_to_name(config);
+
 	default:
 		break;
 	}
@@ -265,6 +353,53 @@ parse_generic_hw_event(const char **str, struct perf_counter_attr *attr)
 	return 1;
 }
 
+static int parse_tracepoint_event(const char **strp,
+				    struct perf_counter_attr *attr)
+{
+	const char *evt_name;
+	char sys_name[MAX_EVENT_LENGTH];
+	char id_buf[4];
+	int fd;
+	unsigned int sys_length, evt_length;
+	u64 id;
+	char evt_path[MAXPATHLEN];
+
+	if (valid_debugfs_mount(debugfs_path))
+		return 0;
+
+	evt_name = strchr(*strp, ':');
+	if (!evt_name)
+		return 0;
+
+	sys_length = evt_name - *strp;
+	if (sys_length >= MAX_EVENT_LENGTH)
+		return 0;
+
+	strncpy(sys_name, *strp, sys_length);
+	sys_name[sys_length] = '\0';
+	evt_name = evt_name + 1;
+	evt_length = strlen(evt_name);
+	if (evt_length >= MAX_EVENT_LENGTH)
+		return 0;
+
+	snprintf(evt_path, MAXPATHLEN, "%s/%s/%s/id", debugfs_path,
+		 sys_name, evt_name);
+	fd = open(evt_path, O_RDONLY);
+	if (fd < 0)
+		return 0;
+
+	if (read(fd, id_buf, sizeof(id_buf)) < 0) {
+		close(fd);
+		return 0;
+	}
+	close(fd);
+	id = atoll(id_buf);
+	attr->config = id;
+	attr->type = PERF_TYPE_TRACEPOINT;
+	*strp = evt_name + evt_length;
+	return 1;
+}
+
 static int check_events(const char *str, unsigned int i)
 {
 	int n;
@@ -374,7 +509,8 @@ parse_event_modifier(const char **strp, struct perf_counter_attr *attr)
  */
 static int parse_event_symbols(const char **str, struct perf_counter_attr *attr)
 {
-	if (!(parse_raw_event(str, attr) ||
+	if (!(parse_tracepoint_event(str, attr) ||
+	      parse_raw_event(str, attr) ||
 	      parse_numeric_event(str, attr) ||
 	      parse_symbolic_event(str, attr) ||
 	      parse_generic_hw_event(str, attr)))
@@ -423,6 +559,42 @@ static const char * const event_type_descriptors[] = {
 };
 
 /*
+ * Print the events from <debugfs_mount_point>/tracing/events
+ */
+
+static void print_tracepoint_events(void)
+{
+	DIR *sys_dir, *evt_dir;
+	struct dirent *sys_next, *evt_next, sys_dirent, evt_dirent;
+	struct stat st;
+	char evt_path[MAXPATHLEN];
+
+	if (valid_debugfs_mount(debugfs_path))
+		return;
+
+	sys_dir = opendir(debugfs_path);
+	if (!sys_dir)
+		goto cleanup;
+
+	for_each_subsystem(sys_dir, sys_dirent, sys_next, evt_path, st) {
+		evt_dir = opendir(evt_path);
+		if (!evt_dir)
+			goto cleanup;
+		for_each_event(sys_dirent, evt_dir, evt_dirent, evt_next,
+								evt_path, st) {
+			snprintf(evt_path, MAXPATHLEN, "%s:%s",
+				 sys_dirent.d_name, evt_dirent.d_name);
+			fprintf(stderr, "  %-40s [%s]\n", evt_path,
+				event_type_descriptors[PERF_TYPE_TRACEPOINT+1]);
+		}
+		closedir(evt_dir);
+	}
+
+cleanup:
+	closedir(sys_dir);
+}
+
+/*
  * Print the help text for the event symbols:
  */
 void print_events(void)
@@ -436,7 +608,7 @@ void print_events(void)
 
 	for (i = 0; i < ARRAY_SIZE(event_symbols); i++, syms++) {
 		type = syms->type + 1;
-		if (type > ARRAY_SIZE(event_type_descriptors))
+		if (type >= ARRAY_SIZE(event_type_descriptors))
 			type = 0;
 
 		if (type != prev_type)
@@ -472,5 +644,7 @@ void print_events(void)
 		"rNNN");
 	fprintf(stderr, "\n");
 
+	print_tracepoint_events();
+
 	exit(129);
 }
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index e3d552908e60..1ea5d09b6eb1 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -3,6 +3,8 @@
  * Parse symbolic events/counts passed in as options:
  */
 
+struct option;
+
 extern int			nr_counters;
 
 extern struct perf_counter_attr attrs[MAX_COUNTERS];
@@ -15,3 +17,6 @@ extern int parse_events(const struct option *opt, const char *str, int unset);
 
 extern void print_events(void);
 
+extern char debugfs_path[];
+extern int valid_debugfs_mount(const char *debugfs);
+
diff --git a/tools/perf/util/string.h b/tools/perf/util/string.h
index 3dca2f654cd0..bf39dfadfd24 100644
--- a/tools/perf/util/string.h
+++ b/tools/perf/util/string.h
@@ -5,4 +5,7 @@
 
 int hex2u64(const char *ptr, u64 *val);
 
+#define _STR(x) #x
+#define STR(x) _STR(x)
+
 #endif
diff --git a/tools/perf/util/strlist.c b/tools/perf/util/strlist.c
index 025a78edfffe..7ad38171dc2b 100644
--- a/tools/perf/util/strlist.c
+++ b/tools/perf/util/strlist.c
@@ -64,6 +64,7 @@ int strlist__add(struct strlist *self, const char *new_entry)
 
 	rb_link_node(&sn->rb_node, parent, p);
 	rb_insert_color(&sn->rb_node, &self->entries);
+	++self->nr_entries;
 
 	return 0;
 }
@@ -155,8 +156,9 @@ struct strlist *strlist__new(bool dupstr, const char *slist)
 	struct strlist *self = malloc(sizeof(*self));
 
 	if (self != NULL) {
-		self->entries = RB_ROOT;
-		self->dupstr = dupstr;
+		self->entries	 = RB_ROOT;
+		self->dupstr	 = dupstr;
+		self->nr_entries = 0;
 		if (slist && strlist__parse_list(self, slist) != 0)
 			goto out_error;
 	}
@@ -182,3 +184,17 @@ void strlist__delete(struct strlist *self)
 		free(self);
 	}
 }
+
+struct str_node *strlist__entry(const struct strlist *self, unsigned int idx)
+{
+	struct rb_node *nd;
+
+	for (nd = rb_first(&self->entries); nd; nd = rb_next(nd)) {
+		struct str_node *pos = rb_entry(nd, struct str_node, rb_node);
+
+		if (!idx--)
+			return pos;
+	}
+
+	return NULL;
+}
diff --git a/tools/perf/util/strlist.h b/tools/perf/util/strlist.h
index 2fdcfee87586..921818e44a54 100644
--- a/tools/perf/util/strlist.h
+++ b/tools/perf/util/strlist.h
@@ -11,7 +11,8 @@ struct str_node {
 
 struct strlist {
 	struct rb_root entries;
-	bool dupstr;
+	unsigned int   nr_entries;
+	bool	       dupstr;
 };
 
 struct strlist *strlist__new(bool dupstr, const char *slist);
@@ -21,11 +22,17 @@ void strlist__remove(struct strlist *self, struct str_node *sn);
 int strlist__load(struct strlist *self, const char *filename);
 int strlist__add(struct strlist *self, const char *str);
 
+struct str_node *strlist__entry(const struct strlist *self, unsigned int idx);
 bool strlist__has_entry(struct strlist *self, const char *entry);
 
 static inline bool strlist__empty(const struct strlist *self)
 {
-	return rb_first(&self->entries) == NULL;
+	return self->nr_entries == 0;
+}
+
+static inline unsigned int strlist__nr_entries(const struct strlist *self)
+{
+	return self->nr_entries;
 }
 
 int strlist__parse_list(struct strlist *self, const char *s);
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 4683b67b5ee4..28106059bf12 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -6,9 +6,15 @@
 #include <libelf.h>
 #include <gelf.h>
 #include <elf.h>
+#include <bfd.h>
 
 const char *sym_hist_filter;
 
+#ifndef DMGL_PARAMS
+#define DMGL_PARAMS      (1 << 0)       /* Include function args */
+#define DMGL_ANSI        (1 << 1)       /* Include const, volatile, etc */
+#endif
+
 static struct symbol *symbol__new(u64 start, u64 len,
 				  const char *name, unsigned int priv_size,
 				  u64 obj_start, int verbose)
@@ -65,6 +71,7 @@ struct dso *dso__new(const char *name, unsigned int sym_priv_size)
 		self->syms = RB_ROOT;
 		self->sym_priv_size = sym_priv_size;
 		self->find_symbol = dso__find_symbol;
+		self->slen_calculated = 0;
 	}
 
 	return self;
@@ -373,36 +380,61 @@ static Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
 	     idx < nr_entries; \
 	     ++idx, pos = gelf_getrela(reldata, idx, &pos_mem))
 
-static int dso__synthesize_plt_symbols(struct  dso *self, Elf *elf,
-				       GElf_Ehdr *ehdr, Elf_Scn *scn_dynsym,
-				       GElf_Shdr *shdr_dynsym,
-				       size_t dynsym_idx, int verbose)
+/*
+ * We need to check if we have a .dynsym, so that we can handle the
+ * .plt, synthesizing its symbols, that aren't on the symtabs (be it
+ * .dynsym or .symtab).
+ * And always look at the original dso, not at debuginfo packages, that
+ * have the PLT data stripped out (shdr_rel_plt.sh_type == SHT_NOBITS).
+ */
+static int dso__synthesize_plt_symbols(struct  dso *self, int verbose)
 {
 	uint32_t nr_rel_entries, idx;
 	GElf_Sym sym;
 	u64 plt_offset;
 	GElf_Shdr shdr_plt;
 	struct symbol *f;
-	GElf_Shdr shdr_rel_plt;
+	GElf_Shdr shdr_rel_plt, shdr_dynsym;
 	Elf_Data *reldata, *syms, *symstrs;
-	Elf_Scn *scn_plt_rel, *scn_symstrs;
+	Elf_Scn *scn_plt_rel, *scn_symstrs, *scn_dynsym;
+	size_t dynsym_idx;
+	GElf_Ehdr ehdr;
 	char sympltname[1024];
-	int nr = 0, symidx;
+	Elf *elf;
+	int nr = 0, symidx, fd, err = 0;
+
+	fd = open(self->name, O_RDONLY);
+	if (fd < 0)
+		goto out;
+
+	elf = elf_begin(fd, ELF_C_READ_MMAP, NULL);
+	if (elf == NULL)
+		goto out_close;
+
+	if (gelf_getehdr(elf, &ehdr) == NULL)
+		goto out_elf_end;
+
+	scn_dynsym = elf_section_by_name(elf, &ehdr, &shdr_dynsym,
+					 ".dynsym", &dynsym_idx);
+	if (scn_dynsym == NULL)
+		goto out_elf_end;
 
-	scn_plt_rel = elf_section_by_name(elf, ehdr, &shdr_rel_plt,
+	scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
 					  ".rela.plt", NULL);
 	if (scn_plt_rel == NULL) {
-		scn_plt_rel = elf_section_by_name(elf, ehdr, &shdr_rel_plt,
+		scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
 						  ".rel.plt", NULL);
 		if (scn_plt_rel == NULL)
-			return 0;
+			goto out_elf_end;
 	}
 
+	err = -1;
+
 	if (shdr_rel_plt.sh_link != dynsym_idx)
-		return 0;
+		goto out_elf_end;
 
-	if (elf_section_by_name(elf, ehdr, &shdr_plt, ".plt", NULL) == NULL)
-		return 0;
+	if (elf_section_by_name(elf, &ehdr, &shdr_plt, ".plt", NULL) == NULL)
+		goto out_elf_end;
 
 	/*
 	 * Fetch the relocation section to find the indexes to the GOT
@@ -410,19 +442,19 @@ static int dso__synthesize_plt_symbols(struct  dso *self, Elf *elf,
 	 */
 	reldata = elf_getdata(scn_plt_rel, NULL);
 	if (reldata == NULL)
-		return -1;
+		goto out_elf_end;
 
 	syms = elf_getdata(scn_dynsym, NULL);
 	if (syms == NULL)
-		return -1;
+		goto out_elf_end;
 
-	scn_symstrs = elf_getscn(elf, shdr_dynsym->sh_link);
+	scn_symstrs = elf_getscn(elf, shdr_dynsym.sh_link);
 	if (scn_symstrs == NULL)
-		return -1;
+		goto out_elf_end;
 
 	symstrs = elf_getdata(scn_symstrs, NULL);
 	if (symstrs == NULL)
-		return -1;
+		goto out_elf_end;
 
 	nr_rel_entries = shdr_rel_plt.sh_size / shdr_rel_plt.sh_entsize;
 	plt_offset = shdr_plt.sh_offset;
@@ -441,7 +473,7 @@ static int dso__synthesize_plt_symbols(struct  dso *self, Elf *elf,
 			f = symbol__new(plt_offset, shdr_plt.sh_entsize,
 					sympltname, self->sym_priv_size, 0, verbose);
 			if (!f)
-				return -1;
+				goto out_elf_end;
 
 			dso__insert_symbol(self, f);
 			++nr;
@@ -459,19 +491,25 @@ static int dso__synthesize_plt_symbols(struct  dso *self, Elf *elf,
 			f = symbol__new(plt_offset, shdr_plt.sh_entsize,
 					sympltname, self->sym_priv_size, 0, verbose);
 			if (!f)
-				return -1;
+				goto out_elf_end;
 
 			dso__insert_symbol(self, f);
 			++nr;
 		}
-	} else {
-		/*
-		 * TODO: There are still one more shdr_rel_plt.sh_type
-		 * I have to investigate, but probably should be ignored.
-		 */
 	}
 
-	return nr;
+	err = 0;
+out_elf_end:
+	elf_end(elf);
+out_close:
+	close(fd);
+
+	if (err == 0)
+		return nr;
+out:
+	fprintf(stderr, "%s: problems reading %s PLT info.\n",
+		__func__, self->name);
+	return 0;
 }
 
 static int dso__load_sym(struct dso *self, int fd, const char *name,
@@ -485,10 +523,9 @@ static int dso__load_sym(struct dso *self, int fd, const char *name,
 	GElf_Shdr shdr;
 	Elf_Data *syms;
 	GElf_Sym sym;
-	Elf_Scn *sec, *sec_dynsym, *sec_strndx;
+	Elf_Scn *sec, *sec_strndx;
 	Elf *elf;
-	size_t dynsym_idx;
-	int nr = 0;
+	int nr = 0, kernel = !strcmp("[kernel]", self->name);
 
 	elf = elf_begin(fd, ELF_C_READ_MMAP, NULL);
 	if (elf == NULL) {
@@ -504,32 +541,11 @@ static int dso__load_sym(struct dso *self, int fd, const char *name,
 		goto out_elf_end;
 	}
 
-	/*
-	 * We need to check if we have a .dynsym, so that we can handle the
-	 * .plt, synthesizing its symbols, that aren't on the symtabs (be it
-	 * .dynsym or .symtab)
-	 */
-	sec_dynsym = elf_section_by_name(elf, &ehdr, &shdr,
-					 ".dynsym", &dynsym_idx);
-	if (sec_dynsym != NULL) {
-		nr = dso__synthesize_plt_symbols(self, elf, &ehdr,
-						 sec_dynsym, &shdr,
-						 dynsym_idx, verbose);
-		if (nr < 0)
-			goto out_elf_end;
-	}
-
-	/*
-	 * But if we have a full .symtab (that is a superset of .dynsym) we
-	 * should add the symbols not in the .dynsyn
-	 */
 	sec = elf_section_by_name(elf, &ehdr, &shdr, ".symtab", NULL);
 	if (sec == NULL) {
-		if (sec_dynsym == NULL)
+		sec = elf_section_by_name(elf, &ehdr, &shdr, ".dynsym", NULL);
+		if (sec == NULL)
 			goto out_elf_end;
-
-		sec = sec_dynsym;
-		gelf_getshdr(sec, &shdr);
 	}
 
 	syms = elf_getdata(sec, NULL);
@@ -555,12 +571,17 @@ static int dso__load_sym(struct dso *self, int fd, const char *name,
 	nr_syms = shdr.sh_size / shdr.sh_entsize;
 
 	memset(&sym, 0, sizeof(sym));
-	self->adjust_symbols = (ehdr.e_type == ET_EXEC ||
+	if (!kernel) {
+		self->adjust_symbols = (ehdr.e_type == ET_EXEC ||
 				elf_section_by_name(elf, &ehdr, &shdr,
 						     ".gnu.prelink_undo",
 						     NULL) != NULL);
+	} else self->adjust_symbols = 0;
+
 	elf_symtab__for_each_symbol(syms, nr_syms, index, sym) {
 		struct symbol *f;
+		const char *name;
+		char *demangled;
 		u64 obj_start;
 		struct section *section = NULL;
 		int is_label = elf_sym__is_label(&sym);
@@ -599,10 +620,19 @@ static int dso__load_sym(struct dso *self, int fd, const char *name,
 				goto out_elf_end;
 			}
 		}
+		/*
+		 * We need to figure out if the object was created from C++ sources
+		 * DWARF DW_compile_unit has this, but we don't always have access
+		 * to it...
+		 */
+		name = elf_sym__name(&sym, symstrs);
+		demangled = bfd_demangle(NULL, name, DMGL_PARAMS | DMGL_ANSI);
+		if (demangled != NULL)
+			name = demangled;
 
-		f = symbol__new(sym.st_value, sym.st_size,
-				elf_sym__name(&sym, symstrs),
+		f = symbol__new(sym.st_value, sym.st_size, name,
 				self->sym_priv_size, obj_start, verbose);
+		free(demangled);
 		if (!f)
 			goto out_elf_end;
 
@@ -668,6 +698,11 @@ more:
 	if (!ret)
 		goto more;
 
+	if (ret > 0) {
+		int nr_plt = dso__synthesize_plt_symbols(self, verbose);
+		if (nr_plt > 0)
+			ret += nr_plt;
+	}
 out:
 	free(name);
 	return ret;
diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
index 7918cffb23cd..2f92b21c712d 100644
--- a/tools/perf/util/symbol.h
+++ b/tools/perf/util/symbol.h
@@ -25,6 +25,7 @@ struct dso {
 	struct symbol    *(*find_symbol)(struct dso *, u64 ip);
 	unsigned int	 sym_priv_size;
 	unsigned char	 adjust_symbols;
+	unsigned char	 slen_calculated;
 	char		 name[0];
 };
 
diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
index b4be6071c105..68fe157d72fb 100644
--- a/tools/perf/util/util.h
+++ b/tools/perf/util/util.h
@@ -50,6 +50,7 @@
 #include <unistd.h>
 #include <stdio.h>
 #include <sys/stat.h>
+#include <sys/statfs.h>
 #include <fcntl.h>
 #include <stddef.h>
 #include <stdlib.h>
@@ -80,6 +81,7 @@
 #include <netdb.h>
 #include <pwd.h>
 #include <inttypes.h>
+#include "../../../include/linux/magic.h"
 
 #ifndef NO_ICONV
 #include <iconv.h>