perf tools: Assorted fixes

index 4ad5dc649716..8ef71669e7a0 100644
@@ -614,6 +614,7 @@ static int stats_print(struct report *rep)
 static void tasks_setup(struct report *rep)
 {
 	memset(&rep->tool, 0, sizeof(rep->tool));
+	rep->tool.ordered_events = true;
 	if (rep->mmaps_mode) {
 		rep->tool.mmap = perf_event__process_mmap;
 		rep->tool.mmap2 = perf_event__process_mmap2;

index bf4ca749d1ac..907267206973 100644
@@ -1803,7 +1803,7 @@ int cmd_record(int argc, const char **argv)
 	err = target__validate(&rec->opts.target);
 	if (err) {
 		target__strerror(&rec->opts.target, err, errbuf, BUFSIZ);
-		ui__warning("%s", errbuf);
+		ui__warning("%s\n", errbuf);
 	}
 
 	err = target__parse_uid(&rec->opts.target);

index ab19a6ee4093..cce926aeb0c0 100644
@@ -1489,6 +1489,7 @@ struct perf_script {
 	bool			show_switch_events;
 	bool			show_namespace_events;
 	bool			show_lost_events;
+	bool			show_round_events;
 	bool			allocated;
 	bool			per_event_dump;
 	struct cpu_map		*cpus;

@@ -2104,6 +2105,16 @@ process_lost_event(struct perf_tool *tool,
 	return 0;
 }
 
+static int
+process_finished_round_event(struct perf_tool *tool __maybe_unused,
+			     union perf_event *event,
+			     struct ordered_events *oe __maybe_unused)
+
+{
+	perf_event__fprintf(event, stdout);
+	return 0;
+}
+
 static void sig_handler(int sig __maybe_unused)
 {
 	session_done = 1;

@@ -2200,6 +2211,10 @@ static int __cmd_script(struct perf_script *script)
 		script->tool.namespaces = process_namespaces_event;
 	if (script->show_lost_events)
 		script->tool.lost = process_lost_event;
+	if (script->show_round_events) {
+		script->tool.ordered_events = false;
+		script->tool.finished_round = process_finished_round_event;
+	}
 
 	if (perf_script__setup_per_event_dump(script)) {
 		pr_err("Couldn't create the per event dump files\n");

@@ -3139,6 +3154,8 @@ int cmd_script(int argc, const char **argv)
 		    "Show namespace events (if recorded)"),
 	OPT_BOOLEAN('\0', "show-lost-events", &script.show_lost_events,
 		    "Show lost events (if recorded)"),
+	OPT_BOOLEAN('\0', "show-round-events", &script.show_round_events,
+		    "Show round events (if recorded)"),
 	OPT_BOOLEAN('\0', "per-event-dump", &script.per_event_dump,
 		    "Dump trace output to files named by the monitored events"),
 	OPT_BOOLEAN('f', "force", &symbol_conf.force, "don't complain, do it"),

index b24afc0e6e81..8b0e4a4315bd 100644
@@ -315,12 +315,8 @@ int filename__read_int(const char *filename, int *value)
 	return err;
 }
 
-/*
- * Parses @value out of @filename with strtoull.
- * By using 0 for base, the strtoull detects the
- * base automatically (see man strtoull).
- */
-int filename__read_ull(const char *filename, unsigned long long *value)
+static int filename__read_ull_base(const char *filename,
+				   unsigned long long *value, int base)
 {
 	char line[64];
 	int fd = open(filename, O_RDONLY), err = -1;

@@ -329,7 +325,7 @@ int filename__read_ull(const char *filename, unsigned long long *value)
 		return -1;
 
 	if (read(fd, line, sizeof(line)) > 0) {
-		*value = strtoull(line, NULL, 0);
+		*value = strtoull(line, NULL, base);
 		if (*value != ULLONG_MAX)
 			err = 0;
 	}

@@ -338,6 +334,25 @@ int filename__read_ull(const char *filename, unsigned long long *value)
 	return err;
 }
 
+/*
+ * Parses @value out of @filename with strtoull.
+ * By using 16 for base to treat the number as hex.
+ */
+int filename__read_xll(const char *filename, unsigned long long *value)
+{
+	return filename__read_ull_base(filename, value, 16);
+}
+
+/*
+ * Parses @value out of @filename with strtoull.
+ * By using 0 for base, the strtoull detects the
+ * base automatically (see man strtoull).
+ */
+int filename__read_ull(const char *filename, unsigned long long *value)
+{
+	return filename__read_ull_base(filename, value, 0);
+}
+
 #define STRERR_BUFSIZE  128     /* For the buffer size of strerror_r */
 
 int filename__read_str(const char *filename, char **buf, size_t *sizep)

index dda49deefb52..8ebee35a6395 100644
@@ -30,6 +30,7 @@ FS(bpf_fs)
 
 int filename__read_int(const char *filename, int *value);
 int filename__read_ull(const char *filename, unsigned long long *value);
+int filename__read_xll(const char *filename, unsigned long long *value);
 int filename__read_str(const char *filename, char **buf, size_t *sizep);
 
 int filename__write_int(const char *filename, int value);

index 8b0e4a4315bd..6a12bbf39f7b 100644
@@ -432,7 +432,8 @@ int procfs__read_str(const char *entry, char **buf, size_t *sizep)
 	return filename__read_str(path, buf, sizep);
 }
 
-int sysfs__read_ull(const char *entry, unsigned long long *value)
+static int sysfs__read_ull_base(const char *entry,
+				unsigned long long *value, int base)
 {
 	char path[PATH_MAX];
 	const char *sysfs = sysfs__mountpoint();

@@ -442,7 +443,17 @@ int sysfs__read_ull(const char *entry, unsigned long long *value)
 
 	snprintf(path, sizeof(path), "%s/%s", sysfs, entry);
 
-	return filename__read_ull(path, value);
+	return filename__read_ull_base(path, value, base);
+}
+
+int sysfs__read_xll(const char *entry, unsigned long long *value)
+{
+	return sysfs__read_ull_base(entry, value, 16);
+}
+
+int sysfs__read_ull(const char *entry, unsigned long long *value)
+{
+	return sysfs__read_ull_base(entry, value, 0);
 }
 
 int sysfs__read_int(const char *entry, int *value)

index 8ebee35a6395..92d03b8396b1 100644
@@ -40,6 +40,7 @@ int procfs__read_str(const char *entry, char **buf, size_t *sizep);
 int sysctl__read_int(const char *sysctl, int *value);
 int sysfs__read_int(const char *entry, int *value);
 int sysfs__read_ull(const char *entry, unsigned long long *value);
+int sysfs__read_xll(const char *entry, unsigned long long *value);
 int sysfs__read_str(const char *entry, char **buf, size_t *sizep);
 int sysfs__read_bool(const char *entry, bool *value);
 

index 914cb8e3d40b..689b6a130dd7 100644
@@ -38,6 +38,10 @@ int kallsyms__parse(const char *filename, void *arg,
 
 		len = hex2u64(line, &start);
 
+		/* Skip the line if we failed to parse the address. */
+		if (!len)
+			continue;
+
 		len++;
 		if (len + 2 >= line_len)
 			continue;

index b05a67464c03..e300a643f65b 100644
@@ -50,6 +50,8 @@ static void machine__threads_init(struct machine *machine)
 
 int machine__init(struct machine *machine, const char *root_dir, pid_t pid)
 {
+	int err = -ENOMEM;
+
 	memset(machine, 0, sizeof(*machine));
 	map_groups__init(&machine->kmaps, machine);
 	RB_CLEAR_NODE(&machine->rb_node);

@@ -79,7 +81,7 @@ int machine__init(struct machine *machine, const char *root_dir, pid_t pid)
 		char comm[64];
 
 		if (thread == NULL)
-			return -ENOMEM;
+			goto out;
 
 		snprintf(comm, sizeof(comm), "[guest/%d]", pid);
 		thread__set_comm(thread, comm, 0);

@@ -87,7 +89,11 @@ int machine__init(struct machine *machine, const char *root_dir, pid_t pid)
 	}
 
 	machine->current_tid = NULL;
+	err = 0;
 
+out:
+	if (err)
+		free(machine->root_dir);
 	return 0;
 }
 

index 7f8553630c4d..537eadd81914 100644
@@ -316,7 +316,6 @@ static int machine__write_buildid_table(struct machine *machine,
 					struct feat_fd *fd)
 {
 	int err = 0;
-	char nm[PATH_MAX];
 	struct dso *pos;
 	u16 kmisc = PERF_RECORD_MISC_KERNEL,
 	    umisc = PERF_RECORD_MISC_USER;

@@ -338,9 +337,8 @@ static int machine__write_buildid_table(struct machine *machine,
 			name = pos->short_name;
 			name_len = pos->short_name_len;
 		} else if (dso__is_kcore(pos)) {
-			machine__mmap_name(machine, nm, sizeof(nm));
-			name = nm;
-			name_len = strlen(nm);
+			name = machine->mmap_name;
+			name_len = strlen(name);
 		} else {
 			name = pos->long_name;
 			name_len = pos->long_name_len;

@@ -813,12 +811,10 @@ static int dso__cache_build_id(struct dso *dso, struct machine *machine)
 	bool is_kallsyms = dso__is_kallsyms(dso);
 	bool is_vdso = dso__is_vdso(dso);
 	const char *name = dso->long_name;
-	char nm[PATH_MAX];
 
 	if (dso__is_kcore(dso)) {
 		is_kallsyms = true;
-		machine__mmap_name(machine, nm, sizeof(nm));
-		name = nm;
+		name = machine->mmap_name;
 	}
 	return build_id_cache__add_b(dso->build_id, sizeof(dso->build_id), name,
 				     dso->nsinfo, is_kallsyms, is_vdso);

index 44e603c27944..4644e751a3e3 100644
@@ -894,8 +894,6 @@ int perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
 				       struct machine *machine)
 {
 	size_t size;
-	const char *mmap_name;
-	char name_buff[PATH_MAX];
 	struct map *map = machine__kernel_map(machine);
 	struct kmap *kmap;
 	int err;

@@ -918,7 +916,6 @@ int perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
 		return -1;
 	}
 
-	mmap_name = machine__mmap_name(machine, name_buff, sizeof(name_buff));
 	if (machine__is_host(machine)) {
 		/*
 		 * kernel uses PERF_RECORD_MISC_USER for user space maps,

@@ -931,7 +928,7 @@ int perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
 
 	kmap = map__kmap(map);
 	size = snprintf(event->mmap.filename, sizeof(event->mmap.filename),
-			"%s%s", mmap_name, kmap->ref_reloc_sym->name) + 1;
+			"%s%s", machine->mmap_name, kmap->ref_reloc_sym->name) + 1;
 	size = PERF_ALIGN(size, sizeof(u64));
 	event->mmap.header.type = PERF_RECORD_MMAP;
 	event->mmap.header.size = (sizeof(event->mmap) -

140 lines not on this page · raw message

index 5ce860b64c74..cb0a20f3a96b 100644
@@ -43,6 +43,7 @@ struct machine {
 	bool		  comm_exec;
 	bool		  kptr_restrict_warned;
 	char		  *root_dir;
+	char		  *mmap_name;
 	struct threads    threads[THREADS__TABLE_SIZE];
 	struct vdso_info  *vdso_info;
 	struct perf_env   *env;

@@ -142,8 +143,6 @@ struct machine *machines__find(struct machines *machines, pid_t pid);
 struct machine *machines__findnew(struct machines *machines, pid_t pid);
 
 void machines__set_id_hdr_size(struct machines *machines, u16 id_hdr_size);
-char *machine__mmap_name(struct machine *machine, char *bf, size_t size);
-
 void machines__set_comm_exec(struct machines *machines, bool comm_exec);
 
 struct machine *machine__new_host(void);

index cc065d4bfafc..dcb81176669a 100644
@@ -1960,8 +1960,7 @@ static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map)
 		pr_debug("Using %s for symbols\n", kallsyms_filename);
 	if (err > 0 && !dso__is_kcore(dso)) {
 		dso->binary_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
-		machine__mmap_name(machine, path, sizeof(path));
-		dso__set_long_name(dso, strdup(path), true);
+		dso__set_long_name(dso, machine->mmap_name, false);
 		map__fixup_start(map);
 		map__fixup_end(map);
 	}

index 447f10e1323e..f5c79110f0d1 100644
@@ -856,14 +856,12 @@ static int machine__get_running_kernel_start(struct machine *machine,
 	return 0;
 }
 
-int __machine__create_kernel_maps(struct machine *machine, struct dso *kernel)
+static int
+__machine__create_kernel_maps(struct machine *machine, struct dso *kernel)
 {
 	int type;
 	u64 start = 0;
 
-	if (machine__get_running_kernel_start(machine, NULL, &start))
-		return -1;
-
 	/* In case of renewal the kernel map, destroy previous one */
 	machine__destroy_kernel_maps(machine);
 

index cb0a20f3a96b..50d587d34459 100644
@@ -238,7 +238,6 @@ size_t machines__fprintf_dsos_buildid(struct machines *machines, FILE *fp,
 				     bool (skip)(struct dso *dso, int parm), int parm);
 
 void machine__destroy_kernel_maps(struct machine *machine);
-int __machine__create_kernel_maps(struct machine *machine, struct dso *kernel);
 int machine__create_kernel_maps(struct machine *machine);
 
 int machines__create_kernel_maps(struct machines *machines, pid_t pid);

index f5c79110f0d1..7838fe56b0c9 100644
@@ -1260,15 +1260,15 @@ int machine__create_kernel_maps(struct machine *machine)
 	return 0;
 }
 
-static void machine__set_kernel_mmap_len(struct machine *machine,
-					 union perf_event *event)
+static void machine__set_kernel_mmap(struct machine *machine,
+				     u64 start, u64 end)
 {
 	int i;
 
 	for (i = 0; i < MAP__NR_TYPES; i++) {
-		machine->vmlinux_maps[i]->start = event->mmap.start;
-		machine->vmlinux_maps[i]->end   = (event->mmap.start +
-						   event->mmap.len);
+		machine->vmlinux_maps[i]->start = start;
+		machine->vmlinux_maps[i]->end   = end;
+
 		/*
 		 * Be a bit paranoid here, some perf.data file came with
 		 * a zero sized synthesized MMAP event for the kernel.

@@ -1373,7 +1373,8 @@ static int machine__process_kernel_mmap_event(struct machine *machine,
 		if (strstr(kernel->long_name, "vmlinux"))
 			dso__set_short_name(kernel, "[kernel.vmlinux]", false);
 
-		machine__set_kernel_mmap_len(machine, event);
+		machine__set_kernel_mmap(machine, event->mmap.start,
+					 event->mmap.start + event->mmap.len);
 
 		/*
 		 * Avoid using a zero address (kptr_restrict) for the ref reloc

index 7838fe56b0c9..279eeb87c594 100644
@@ -1028,13 +1028,6 @@ int machine__load_vmlinux_path(struct machine *machine, enum map_type type)
 	return ret;
 }
 
-static void map_groups__fixup_end(struct map_groups *mg)
-{
-	int i;
-	for (i = 0; i < MAP__NR_TYPES; ++i)
-		__map_groups__fixup_end(mg, i);
-}
-
 static char *get_kernel_version(const char *root_dir)
 {
 	char version[PATH_MAX];

@@ -1220,6 +1213,24 @@ static int machine__create_modules(struct machine *machine)
 	return 0;
 }
 
+static void machine__set_kernel_mmap(struct machine *machine,
+				     u64 start, u64 end)
+{
+	int i;
+
+	for (i = 0; i < MAP__NR_TYPES; i++) {
+		machine->vmlinux_maps[i]->start = start;
+		machine->vmlinux_maps[i]->end   = end;
+
+		/*
+		 * Be a bit paranoid here, some perf.data file came with
+		 * a zero sized synthesized MMAP event for the kernel.
+		 */
+		if (machine->vmlinux_maps[i]->end == 0)
+			machine->vmlinux_maps[i]->end = ~0ULL;
+	}
+}
+
 int machine__create_kernel_maps(struct machine *machine)
 {
 	struct dso *kernel = machine__get_kernel(machine);

@@ -1244,11 +1255,6 @@ int machine__create_kernel_maps(struct machine *machine)
 				 "continuing anyway...\n", machine->pid);
 	}
 
-	/*
-	 * Now that we have all the maps created, just set the ->end of them:
-	 */
-	map_groups__fixup_end(&machine->kmaps);
-
 	if (!machine__get_running_kernel_start(machine, &name, &addr)) {
 		if (name &&
 		    maps__set_kallsyms_ref_reloc_sym(machine->vmlinux_maps, name, addr)) {

@@ -1257,27 +1263,10 @@ int machine__create_kernel_maps(struct machine *machine)
 		}
 	}
 
+	machine__set_kernel_mmap(machine, addr, 0);
 	return 0;
 }
 
-static void machine__set_kernel_mmap(struct machine *machine,
-				     u64 start, u64 end)
-{
-	int i;
-
-	for (i = 0; i < MAP__NR_TYPES; i++) {
-		machine->vmlinux_maps[i]->start = start;
-		machine->vmlinux_maps[i]->end   = end;
-
-		/*
-		 * Be a bit paranoid here, some perf.data file came with
-		 * a zero sized synthesized MMAP event for the kernel.
-		 */
-		if (machine->vmlinux_maps[i]->end == 0)
-			machine->vmlinux_maps[i]->end = ~0ULL;
-	}
-}
-
 static bool machine__uses_kcore(struct machine *machine)
 {
 	struct dso *dso;

index 279eeb87c594..441d09d97f3d 100644
@@ -1005,7 +1005,7 @@ int __machine__load_kallsyms(struct machine *machine, const char *filename,
 		 * kernel, with modules between them, fixup the end of all
 		 * sections.
 		 */
-		__map_groups__fixup_end(&machine->kmaps, type);
+		map_groups__fixup_end(&machine->kmaps, type);
 	}
 
 	return ret;

index 2de770511e70..6d1e4dc2709f 100644
@@ -1124,7 +1124,7 @@ int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *syms_ss,
 			 * We need to fixup this here too because we create new
 			 * maps here, for things like vsyscall sections.
 			 */
-			__map_groups__fixup_end(kmaps, map->type);
+			map_groups__fixup_end(kmaps, map->type);
 		}
 	}
 	err = nr;

index dcb81176669a..fe15dafaef66 100644
@@ -228,7 +228,7 @@ void symbols__fixup_end(struct rb_root *symbols)
 		curr->end = roundup(curr->start, 4096) + 4096;
 }
 
-void __map_groups__fixup_end(struct map_groups *mg, enum map_type type)
+void map_groups__fixup_end(struct map_groups *mg, enum map_type type)
 {
 	struct maps *maps = &mg->maps[type];
 	struct map *next, *curr;

index 0563f33c1eb3..cf955f1d1718 100644
@@ -316,7 +316,7 @@ void __symbols__insert(struct rb_root *symbols, struct symbol *sym, bool kernel)
 void symbols__insert(struct rb_root *symbols, struct symbol *sym);
 void symbols__fixup_duplicate(struct rb_root *symbols);
 void symbols__fixup_end(struct rb_root *symbols);
-void __map_groups__fixup_end(struct map_groups *mg, enum map_type type);
+void map_groups__fixup_end(struct map_groups *mg, enum map_type type);
 
 typedef int (*mapfn_t)(u64 start, u64 len, u64 pgoff, void *data);
 int file__read_maps(int fd, bool exe, mapfn_t mapfn, void *data,

index f6789fb029d6..58349297f9fb 100644
@@ -56,7 +56,7 @@ int test__vmlinux_matches_kallsyms(struct test *test __maybe_unused, int subtest
 	 * 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) {
+	if (machine__load_kallsyms(&kallsyms, "/proc/kallsyms", type) <= 0) {
 		pr_debug("dso__load_kallsyms ");
 		goto out;
 	}

index 441d09d97f3d..a9e470139722 100644
@@ -151,7 +151,7 @@ struct machine *machine__new_kallsyms(void)
 	 *    ask for not using the kcore parsing code, once this one is fixed
 	 *    to create a map per module.
 	 */
-	if (machine && __machine__load_kallsyms(machine, "/proc/kallsyms", MAP__FUNCTION, true) <= 0) {
+	if (machine && machine__load_kallsyms(machine, "/proc/kallsyms", MAP__FUNCTION) <= 0) {
 		machine__delete(machine);
 		machine = NULL;
 	}

@@ -992,11 +992,11 @@ int machines__create_kernel_maps(struct machines *machines, pid_t pid)
 	return machine__create_kernel_maps(machine);
 }
 
-int __machine__load_kallsyms(struct machine *machine, const char *filename,
-			     enum map_type type, bool no_kcore)
+int machine__load_kallsyms(struct machine *machine, const char *filename,
+			     enum map_type type)
 {
 	struct map *map = machine__kernel_map(machine);
-	int ret = __dso__load_kallsyms(map->dso, filename, map, no_kcore);
+	int ret = __dso__load_kallsyms(map->dso, filename, map, true);
 
 	if (ret > 0) {
 		dso__set_loaded(map->dso, type);

@@ -1011,12 +1011,6 @@ int __machine__load_kallsyms(struct machine *machine, const char *filename,
 	return ret;
 }
 
-int machine__load_kallsyms(struct machine *machine, const char *filename,
-			   enum map_type type)
-{
-	return __machine__load_kallsyms(machine, filename, type, false);
-}
-
 int machine__load_vmlinux_path(struct machine *machine, enum map_type type)
 {
 	struct map *map = machine__kernel_map(machine);

index 50d587d34459..66cc200ef86f 100644
@@ -225,8 +225,6 @@ struct map *machine__findnew_module_map(struct machine *machine, u64 start,
 					const char *filename);
 int arch__fix_module_text_start(u64 *start, const char *name);
 
-int __machine__load_kallsyms(struct machine *machine, const char *filename,
-			     enum map_type type, bool no_kcore);
 int machine__load_kallsyms(struct machine *machine, const char *filename,
 			   enum map_type type);
 int machine__load_vmlinux_path(struct machine *machine, enum map_type type);

index 4644e751a3e3..f0a6cbd033cc 100644
@@ -1588,17 +1588,6 @@ int machine__resolve(struct machine *machine, struct addr_location *al,
 		return -1;
 
 	dump_printf(" ... thread: %s:%d\n", thread__comm_str(thread), thread->tid);
-	/*
-	 * Have we already created the kernel maps for this machine?
-	 *
-	 * This should have happened earlier, when we processed the kernel MMAP
-	 * events, but for older perf.data files there was no such thing, so do
-	 * it now.
-	 */
-	if (sample->cpumode == PERF_RECORD_MISC_KERNEL &&
-	    machine__kernel_map(machine) == NULL)
-		machine__create_kernel_maps(machine);
-
 	thread__find_addr_map(thread, sample->cpumode, MAP__FUNCTION, sample->ip, al);
 	dump_printf(" ...... dso: %s\n",
 		    al->map ? al->map->dso->long_name :

index fe15dafaef66..ea002b27b39d 100644
@@ -1580,9 +1580,7 @@ int dso__load(struct dso *dso, struct map *map)
 	for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
 		struct symsrc *ss = &ss_[ss_pos];
 		bool next_slot = false;
-		bool is_reg;
 		bool nsexit;
-		int sirc;
 
 		enum dso_binary_type symtab_type = binary_type_symtab[i];
 

@@ -1599,18 +1597,15 @@ int dso__load(struct dso *dso, struct map *map)
 		if (nsexit)
 			nsinfo__mountns_exit(&nsc);
 
-		is_reg = is_regular_file(name);
-		sirc = symsrc__init(ss, dso, name, symtab_type);
+		if (!is_regular_file(name))
+			continue;
+
+		if (symsrc__init(ss, dso, name, symtab_type) < 0)
+			continue;
 
 		if (nsexit)
 			nsinfo__mountns_enter(dso->nsinfo, &nsc);
 
-		if (!is_reg || sirc < 0) {
-			if (sirc >= 0)
-				symsrc__destroy(ss);
-			continue;
-		}
-
 		if (!syms_ss && symsrc__has_symtab(ss)) {
 			syms_ss = ss;
 			next_slot = true;

index 260418969120..2f008067d989 100644
@@ -37,6 +37,19 @@ static int init_live_machine(struct machine *machine)
 						  mmap_handler, machine, true, 500);
 }
 
+/*
+ * We need to keep these functions global, despite the
+ * fact that they are used only locally in this object,
+ * in order to keep them around even if the binary is
+ * stripped. If they are gone, the unwind check for
+ * symbol fails.
+ */
+int test_dwarf_unwind__thread(struct thread *thread);
+int test_dwarf_unwind__compare(void *p1, void *p2);
+int test_dwarf_unwind__krava_3(struct thread *thread);
+int test_dwarf_unwind__krava_2(struct thread *thread);
+int test_dwarf_unwind__krava_1(struct thread *thread);
+
 #define MAX_STACK 8
 
 static int unwind_entry(struct unwind_entry *entry, void *arg)

@@ -45,12 +58,12 @@ static int unwind_entry(struct unwind_entry *entry, void *arg)
 	char *symbol = entry->sym ? entry->sym->name : NULL;
 	static const char *funcs[MAX_STACK] = {
 		"test__arch_unwind_sample",
-		"unwind_thread",
-		"compare",
+		"test_dwarf_unwind__thread",
+		"test_dwarf_unwind__compare",
 		"bsearch",
-		"krava_3",
-		"krava_2",
-		"krava_1",
+		"test_dwarf_unwind__krava_3",
+		"test_dwarf_unwind__krava_2",
+		"test_dwarf_unwind__krava_1",
 		"test__dwarf_unwind"
 	};
 	/*

@@ -77,7 +90,7 @@ static int unwind_entry(struct unwind_entry *entry, void *arg)
 	return strcmp((const char *) symbol, funcs[idx]);
 }
 
-static noinline int unwind_thread(struct thread *thread)
+noinline int test_dwarf_unwind__thread(struct thread *thread)
 {
 	struct perf_sample sample;
 	unsigned long cnt = 0;

@@ -108,7 +121,7 @@ static noinline int unwind_thread(struct thread *thread)
 
 static int global_unwind_retval = -INT_MAX;
 
-static noinline int compare(void *p1, void *p2)
+noinline int test_dwarf_unwind__compare(void *p1, void *p2)
 {
 	/* Any possible value should be 'thread' */
 	struct thread *thread = *(struct thread **)p1;

@@ -117,17 +130,17 @@ static noinline int compare(void *p1, void *p2)
 		/* Call unwinder twice for both callchain orders. */
 		callchain_param.order = ORDER_CALLER;
 
-		global_unwind_retval = unwind_thread(thread);
+		global_unwind_retval = test_dwarf_unwind__thread(thread);
 		if (!global_unwind_retval) {
 			callchain_param.order = ORDER_CALLEE;
-			global_unwind_retval = unwind_thread(thread);
+			global_unwind_retval = test_dwarf_unwind__thread(thread);
 		}
 	}
 
 	return p1 - p2;
 }
 
-static noinline int krava_3(struct thread *thread)
+noinline int test_dwarf_unwind__krava_3(struct thread *thread)
 {
 	struct thread *array[2] = {thread, thread};
 	void *fp = &bsearch;

@@ -141,18 +154,19 @@ static noinline int krava_3(struct thread *thread)
 			size_t, int (*)(void *, void *));
 
 	_bsearch = fp;
-	_bsearch(array, &thread, 2, sizeof(struct thread **), compare);
+	_bsearch(array, &thread, 2, sizeof(struct thread **),
+		 test_dwarf_unwind__compare);
 	return global_unwind_retval;
 }
 
-static noinline int krava_2(struct thread *thread)
+noinline int test_dwarf_unwind__krava_2(struct thread *thread)
 {
-	return krava_3(thread);
+	return test_dwarf_unwind__krava_3(thread);
 }
 
-static noinline int krava_1(struct thread *thread)
+noinline int test_dwarf_unwind__krava_1(struct thread *thread)
 {
-	return krava_2(thread);
+	return test_dwarf_unwind__krava_2(thread);
 }
 
 int test__dwarf_unwind(struct test *test __maybe_unused, int subtest __maybe_unused)

@@ -189,7 +203,7 @@ int test__dwarf_unwind(struct test *test __maybe_unused, int subtest __maybe_unu
 		goto out;
 	}
 
-	err = krava_1(thread);
+	err = test_dwarf_unwind__krava_1(thread);
 	thread__put(thread);
 
  out:

index 2da4d0456a03..e8514f651865 100644
@@ -111,17 +111,20 @@ struct sort_entry sort_thread = {
 
 /* --sort comm */
 
+/*
+ * We can't use pointer comparison in functions below,
+ * because it gives different results based on pointer
+ * values, which could break some sorting assumptions.
+ */
 static int64_t
 sort__comm_cmp(struct hist_entry *left, struct hist_entry *right)
 {
-	/* Compare the addr that should be unique among comm */
 	return strcmp(comm__str(right->comm), comm__str(left->comm));
 }
 
 static int64_t
 sort__comm_collapse(struct hist_entry *left, struct hist_entry *right)
 {
-	/* Compare the addr that should be unique among comm */
 	return strcmp(comm__str(right->comm), comm__str(left->comm));
 }