1 files changed, 556 insertions, 48 deletions

diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c
index 40399cbcca77..aa9c58bbf9d3 100644
--- a/tools/perf/util/thread.c
+++ b/tools/perf/util/thread.c
@@ -1,90 +1,598 @@
-#include "../perf.h"
+// SPDX-License-Identifier: GPL-2.0
+#include <elf.h>
+#include <errno.h>
+#include <fcntl.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
+#include <linux/kernel.h>
+#include <linux/zalloc.h>
+#include "dso.h"
 #include "session.h"
 #include "thread.h"
-#include "util.h"
+#include "thread-stack.h"
 #include "debug.h"
+#include "namespaces.h"
+#include "comm.h"
+#include "map.h"
+#include "symbol.h"
+#include "unwind.h"
+#include "callchain.h"
+#include "dwarf-regs.h"
 
-struct thread *thread__new(pid_t pid)
+#include <api/fs/fs.h>
+
+int thread__init_maps(struct thread *thread, struct machine *machine)
 {
-	struct thread *self = zalloc(sizeof(*self));
+	pid_t pid = thread__pid(thread);
+
+	if (pid == thread__tid(thread) || pid == -1) {
+		thread__set_maps(thread, maps__new(machine));
+	} else {
+		struct thread *leader = machine__findnew_thread(machine, pid, pid);
 
-	if (self != NULL) {
-		map_groups__init(&self->mg);
-		self->pid = pid;
-		self->ppid = -1;
-		self->comm = malloc(32);
-		if (self->comm)
-			snprintf(self->comm, 32, ":%d", self->pid);
+		if (leader) {
+			thread__set_maps(thread, maps__get(thread__maps(leader)));
+			thread__put(leader);
+		}
 	}
 
-	return self;
+	return thread__maps(thread) ? 0 : -1;
 }
 
-void thread__delete(struct thread *self)
+struct thread *thread__new(pid_t pid, pid_t tid)
+	NO_THREAD_SAFETY_ANALYSIS /* Allocation/creation is inherently single threaded. */
 {
-	map_groups__exit(&self->mg);
-	free(self->comm);
-	free(self);
+	RC_STRUCT(thread) *_thread = zalloc(sizeof(*_thread));
+	struct thread *thread;
+
+	if (ADD_RC_CHK(thread, _thread) != NULL) {
+		struct comm *comm;
+		char comm_str[32];
+
+		thread__set_pid(thread, pid);
+		thread__set_tid(thread, tid);
+		thread__set_ppid(thread, -1);
+		thread__set_cpu(thread, -1);
+		thread__set_guest_cpu(thread, -1);
+		thread__set_e_machine(thread, EM_NONE);
+		thread__set_lbr_stitch_enable(thread, false);
+		INIT_LIST_HEAD(thread__namespaces_list(thread));
+		INIT_LIST_HEAD(thread__comm_list(thread));
+		init_rwsem(thread__namespaces_lock(thread));
+		init_rwsem(thread__comm_lock(thread));
+
+		snprintf(comm_str, sizeof(comm_str), ":%d", tid);
+		comm = comm__new(comm_str, 0, false);
+		if (!comm)
+			goto err_thread;
+
+		list_add(&comm->list, thread__comm_list(thread));
+		refcount_set(thread__refcnt(thread), 1);
+		/* Thread holds first ref to nsdata. */
+		RC_CHK_ACCESS(thread)->nsinfo = nsinfo__new(pid);
+		srccode_state_init(thread__srccode_state(thread));
+	}
+
+	return thread;
+
+err_thread:
+	thread__delete(thread);
+	return NULL;
 }
 
-int thread__set_comm(struct thread *self, const char *comm)
+static void (*thread__priv_destructor)(void *priv);
+
+void thread__set_priv_destructor(void (*destructor)(void *priv))
 {
-	int err;
+	assert(thread__priv_destructor == NULL);
+
+	thread__priv_destructor = destructor;
+}
+
+void thread__delete(struct thread *thread)
+{
+	struct namespaces *namespaces, *tmp_namespaces;
+	struct comm *comm, *tmp_comm;
+
+	thread_stack__free(thread);
+
+	if (thread__maps(thread)) {
+		maps__put(thread__maps(thread));
+		thread__set_maps(thread, NULL);
+	}
+	down_write(thread__namespaces_lock(thread));
+	list_for_each_entry_safe(namespaces, tmp_namespaces,
+				 thread__namespaces_list(thread), list) {
+		list_del_init(&namespaces->list);
+		namespaces__free(namespaces);
+	}
+	up_write(thread__namespaces_lock(thread));
+
+	down_write(thread__comm_lock(thread));
+	list_for_each_entry_safe(comm, tmp_comm, thread__comm_list(thread), list) {
+		list_del_init(&comm->list);
+		comm__free(comm);
+	}
+	up_write(thread__comm_lock(thread));
+
+	nsinfo__zput(RC_CHK_ACCESS(thread)->nsinfo);
+	srccode_state_free(thread__srccode_state(thread));
+
+	exit_rwsem(thread__namespaces_lock(thread));
+	exit_rwsem(thread__comm_lock(thread));
+	thread__free_stitch_list(thread);
+
+	if (thread__priv_destructor)
+		thread__priv_destructor(thread__priv(thread));
+
+	RC_CHK_FREE(thread);
+}
+
+struct thread *thread__get(struct thread *thread)
+{
+	struct thread *result;
+
+	if (RC_CHK_GET(result, thread))
+		refcount_inc(thread__refcnt(thread));
+
+	return result;
+}
+
+void thread__put(struct thread *thread)
+{
+	if (thread && refcount_dec_and_test(thread__refcnt(thread)))
+		thread__delete(thread);
+	else
+		RC_CHK_PUT(thread);
+}
+
+static struct namespaces *__thread__namespaces(struct thread *thread)
+{
+	if (list_empty(thread__namespaces_list(thread)))
+		return NULL;
+
+	return list_first_entry(thread__namespaces_list(thread), struct namespaces, list);
+}
+
+struct namespaces *thread__namespaces(struct thread *thread)
+{
+	struct namespaces *ns;
+
+	down_read(thread__namespaces_lock(thread));
+	ns = __thread__namespaces(thread);
+	up_read(thread__namespaces_lock(thread));
+
+	return ns;
+}
+
+static int __thread__set_namespaces(struct thread *thread, u64 timestamp,
+				    struct perf_record_namespaces *event)
+{
+	struct namespaces *new, *curr = __thread__namespaces(thread);
+
+	new = namespaces__new(event);
+	if (!new)
+		return -ENOMEM;
+
+	list_add(&new->list, thread__namespaces_list(thread));
+
+	if (timestamp && curr) {
+		/*
+		 * setns syscall must have changed few or all the namespaces
+		 * of this thread. Update end time for the namespaces
+		 * previously used.
+		 */
+		curr = list_next_entry(new, list);
+		curr->end_time = timestamp;
+	}
+
+	return 0;
+}
+
+int thread__set_namespaces(struct thread *thread, u64 timestamp,
+			   struct perf_record_namespaces *event)
+{
+	int ret;
+
+	down_write(thread__namespaces_lock(thread));
+	ret = __thread__set_namespaces(thread, timestamp, event);
+	up_write(thread__namespaces_lock(thread));
+	return ret;
+}
+
+static struct comm *__thread__comm(struct thread *thread)
+	SHARED_LOCKS_REQUIRED(thread__comm_lock(thread))
+{
+	if (list_empty(thread__comm_list(thread)))
+		return NULL;
+
+	return list_first_entry(thread__comm_list(thread), struct comm, list);
+}
+
+struct comm *thread__comm(struct thread *thread)
+{
+	struct comm *res = NULL;
+
+	down_read(thread__comm_lock(thread));
+	res = __thread__comm(thread);
+	up_read(thread__comm_lock(thread));
+	return res;
+}
+
+struct comm *thread__exec_comm(struct thread *thread)
+{
+	struct comm *comm, *last = NULL, *second_last = NULL;
 
-	if (self->comm)
-		free(self->comm);
-	self->comm = strdup(comm);
-	err = self->comm == NULL ? -ENOMEM : 0;
-	if (!err) {
-		self->comm_set = true;
+	down_read(thread__comm_lock(thread));
+	list_for_each_entry(comm, thread__comm_list(thread), list) {
+		if (comm->exec) {
+			up_read(thread__comm_lock(thread));
+			return comm;
+		}
+		second_last = last;
+		last = comm;
 	}
+	up_read(thread__comm_lock(thread));
+
+	/*
+	 * 'last' with no start time might be the parent's comm of a synthesized
+	 * thread (created by processing a synthesized fork event). For a main
+	 * thread, that is very probably wrong. Prefer a later comm to avoid
+	 * that case.
+	 */
+	if (second_last && !last->start && thread__pid(thread) == thread__tid(thread))
+		return second_last;
+
+	return last;
+}
+
+static int ____thread__set_comm(struct thread *thread, const char *str,
+				u64 timestamp, bool exec)
+	EXCLUSIVE_LOCKS_REQUIRED(thread__comm_lock(thread))
+{
+	struct comm *new, *curr = __thread__comm(thread);
+
+	/* Override the default :tid entry */
+	if (!thread__comm_set(thread)) {
+		int err = comm__override(curr, str, timestamp, exec);
+		if (err)
+			return err;
+	} else {
+		new = comm__new(str, timestamp, exec);
+		if (!new)
+			return -ENOMEM;
+		list_add(&new->list, thread__comm_list(thread));
+
+		if (exec)
+			unwind__flush_access(thread__maps(thread));
+	}
+
+	thread__set_comm_set(thread, true);
+
+	return 0;
+}
+
+int __thread__set_comm(struct thread *thread, const char *str, u64 timestamp,
+		       bool exec)
+{
+	int ret;
+
+	down_write(thread__comm_lock(thread));
+	ret = ____thread__set_comm(thread, str, timestamp, exec);
+	up_write(thread__comm_lock(thread));
+	return ret;
+}
+
+int thread__set_comm_from_proc(struct thread *thread)
+{
+	char path[64];
+	char *comm = NULL;
+	size_t sz;
+	int err = -1;
+
+	if (!(snprintf(path, sizeof(path), "%d/task/%d/comm",
+		       thread__pid(thread), thread__tid(thread)) >= (int)sizeof(path)) &&
+	    procfs__read_str(path, &comm, &sz) == 0) {
+		comm[sz - 1] = '\0';
+		err = thread__set_comm(thread, comm, 0);
+	}
+
 	return err;
 }
 
-int thread__comm_len(struct thread *self)
+static const char *__thread__comm_str(struct thread *thread)
+	SHARED_LOCKS_REQUIRED(thread__comm_lock(thread))
 {
-	if (!self->comm_len) {
-		if (!self->comm)
-			return 0;
-		self->comm_len = strlen(self->comm);
+	const struct comm *comm = __thread__comm(thread);
+
+	if (!comm)
+		return NULL;
+
+	return comm__str(comm);
+}
+
+const char *thread__comm_str(struct thread *thread)
+{
+	const char *str;
+
+	down_read(thread__comm_lock(thread));
+	str = __thread__comm_str(thread);
+	up_read(thread__comm_lock(thread));
+
+	return str;
+}
+
+static int __thread__comm_len(struct thread *thread, const char *comm)
+{
+	if (!comm)
+		return 0;
+	thread__set_comm_len(thread, strlen(comm));
+
+	return thread__var_comm_len(thread);
+}
+
+/* CHECKME: it should probably better return the max comm len from its comm list */
+int thread__comm_len(struct thread *thread)
+{
+	int comm_len = thread__var_comm_len(thread);
+
+	if (!comm_len) {
+		const char *comm;
+
+		down_read(thread__comm_lock(thread));
+		comm = __thread__comm_str(thread);
+		comm_len = __thread__comm_len(thread, comm);
+		up_read(thread__comm_lock(thread));
 	}
 
-	return self->comm_len;
+	return comm_len;
 }
 
 size_t thread__fprintf(struct thread *thread, FILE *fp)
 {
-	return fprintf(fp, "Thread %d %s\n", thread->pid, thread->comm) +
-	       map_groups__fprintf(&thread->mg, verbose, fp);
+	return fprintf(fp, "Thread %d %s\n", thread__tid(thread), thread__comm_str(thread)) +
+	       maps__fprintf(thread__maps(thread), fp);
 }
 
-void thread__insert_map(struct thread *self, struct map *map)
+int thread__insert_map(struct thread *thread, struct map *map)
 {
-	map_groups__fixup_overlappings(&self->mg, map, verbose, stderr);
-	map_groups__insert(&self->mg, map);
+	int ret;
+
+	ret = unwind__prepare_access(thread__maps(thread), map, NULL);
+	if (ret)
+		return ret;
+
+	return maps__fixup_overlap_and_insert(thread__maps(thread), map);
 }
 
-int thread__fork(struct thread *self, struct thread *parent)
+struct thread__prepare_access_maps_cb_args {
+	int err;
+	struct maps *maps;
+};
+
+static int thread__prepare_access_maps_cb(struct map *map, void *data)
 {
-	int i;
+	bool initialized = false;
+	struct thread__prepare_access_maps_cb_args *args = data;
 
-	if (parent->comm_set) {
-		if (self->comm)
-			free(self->comm);
-		self->comm = strdup(parent->comm);
-		if (!self->comm)
-			return -ENOMEM;
-		self->comm_set = true;
+	args->err = unwind__prepare_access(args->maps, map, &initialized);
+
+	return (args->err || initialized) ? 1 : 0;
+}
+
+static int thread__prepare_access(struct thread *thread)
+{
+	struct thread__prepare_access_maps_cb_args args = {
+		.err = 0,
+	};
+
+	if (dwarf_callchain_users) {
+		args.maps = thread__maps(thread);
+		maps__for_each_map(thread__maps(thread), thread__prepare_access_maps_cb, &args);
 	}
 
-	for (i = 0; i < MAP__NR_TYPES; ++i)
-		if (map_groups__clone(&self->mg, &parent->mg, i) < 0)
+	return args.err;
+}
+
+static int thread__clone_maps(struct thread *thread, struct thread *parent, bool do_maps_clone)
+{
+	/* This is new thread, we share map groups for process. */
+	if (thread__pid(thread) == thread__pid(parent))
+		return thread__prepare_access(thread);
+
+	if (maps__equal(thread__maps(thread), thread__maps(parent))) {
+		pr_debug("broken map groups on thread %d/%d parent %d/%d\n",
+			 thread__pid(thread), thread__tid(thread),
+			 thread__pid(parent), thread__tid(parent));
+		return 0;
+	}
+	/* But this one is new process, copy maps. */
+	return do_maps_clone ? maps__copy_from(thread__maps(thread), thread__maps(parent)) : 0;
+}
+
+int thread__fork(struct thread *thread, struct thread *parent, u64 timestamp, bool do_maps_clone)
+{
+	if (thread__comm_set(parent)) {
+		const char *comm = thread__comm_str(parent);
+		int err;
+		if (!comm)
 			return -ENOMEM;
+		err = thread__set_comm(thread, comm, timestamp);
+		if (err)
+			return err;
+	}
+
+	thread__set_ppid(thread, thread__tid(parent));
+	return thread__clone_maps(thread, parent, do_maps_clone);
+}
 
-	self->ppid = parent->pid;
+void thread__find_cpumode_addr_location(struct thread *thread, u64 addr,
+					bool symbols, struct addr_location *al)
+{
+	size_t i;
+	const u8 cpumodes[] = {
+		PERF_RECORD_MISC_USER,
+		PERF_RECORD_MISC_KERNEL,
+		PERF_RECORD_MISC_GUEST_USER,
+		PERF_RECORD_MISC_GUEST_KERNEL
+	};
 
-	return 0;
+	for (i = 0; i < ARRAY_SIZE(cpumodes); i++) {
+		if (symbols)
+			thread__find_symbol(thread, cpumodes[i], addr, al);
+		else
+			thread__find_map(thread, cpumodes[i], addr, al);
+
+		if (al->map)
+			break;
+	}
+}
+
+static uint16_t read_proc_e_machine_for_pid(pid_t pid)
+{
+	char path[6 /* "/proc/" */ + 11 /* max length of pid */ + 5 /* "/exe\0" */];
+	int fd;
+	uint16_t e_machine = EM_NONE;
+
+	snprintf(path, sizeof(path), "/proc/%d/exe", pid);
+	fd = open(path, O_RDONLY);
+	if (fd >= 0) {
+		_Static_assert(offsetof(Elf32_Ehdr, e_machine) == 18, "Unexpected offset");
+		_Static_assert(offsetof(Elf64_Ehdr, e_machine) == 18, "Unexpected offset");
+		if (pread(fd, &e_machine, sizeof(e_machine), 18) != sizeof(e_machine))
+			e_machine = EM_NONE;
+		close(fd);
+	}
+	return e_machine;
+}
+
+static int thread__e_machine_callback(struct map *map, void *machine)
+{
+	struct dso *dso = map__dso(map);
+
+	_Static_assert(0 == EM_NONE, "Unexpected EM_NONE");
+	if (!dso)
+		return EM_NONE;
+
+	return dso__e_machine(dso, machine);
+}
+
+uint16_t thread__e_machine(struct thread *thread, struct machine *machine)
+{
+	pid_t tid, pid;
+	uint16_t e_machine = RC_CHK_ACCESS(thread)->e_machine;
+
+	if (e_machine != EM_NONE)
+		return e_machine;
+
+	tid = thread__tid(thread);
+	pid = thread__pid(thread);
+	if (pid != tid) {
+		struct thread *parent = machine__findnew_thread(machine, pid, pid);
+
+		if (parent) {
+			e_machine = thread__e_machine(parent, machine);
+			thread__put(parent);
+			thread__set_e_machine(thread, e_machine);
+			return e_machine;
+		}
+		/* Something went wrong, fallback. */
+	}
+	/* Reading on the PID thread. First try to find from the maps. */
+	e_machine = maps__for_each_map(thread__maps(thread),
+				       thread__e_machine_callback,
+				       machine);
+	if (e_machine == EM_NONE) {
+		/* Maps failed, perhaps we're live with map events disabled. */
+		bool is_live = machine->machines == NULL;
+
+		if (!is_live) {
+			/* Check if the session has a data file. */
+			struct perf_session *session = container_of(machine->machines,
+								    struct perf_session,
+								    machines);
+
+			is_live = !!session->data;
+		}
+		/* Read from /proc/pid/exe if live. */
+		if (is_live)
+			e_machine = read_proc_e_machine_for_pid(pid);
+	}
+	if (e_machine != EM_NONE)
+		thread__set_e_machine(thread, e_machine);
+	else
+		e_machine = EM_HOST;
+	return e_machine;
+}
+
+struct thread *thread__main_thread(struct machine *machine, struct thread *thread)
+{
+	if (thread__pid(thread) == thread__tid(thread))
+		return thread__get(thread);
+
+	if (thread__pid(thread) == -1)
+		return NULL;
+
+	return machine__find_thread(machine, thread__pid(thread), thread__pid(thread));
+}
+
+int thread__memcpy(struct thread *thread, struct machine *machine,
+		   void *buf, u64 ip, int len, bool *is64bit)
+{
+	u8 cpumode = PERF_RECORD_MISC_USER;
+	struct addr_location al;
+	struct dso *dso;
+	long offset;
+
+	if (machine__kernel_ip(machine, ip))
+		cpumode = PERF_RECORD_MISC_KERNEL;
+
+	addr_location__init(&al);
+	if (!thread__find_map(thread, cpumode, ip, &al)) {
+		addr_location__exit(&al);
+		return -1;
+	}
+
+	dso = map__dso(al.map);
+
+	if (!dso || dso__data(dso)->status == DSO_DATA_STATUS_ERROR || map__load(al.map) < 0) {
+		addr_location__exit(&al);
+		return -1;
+	}
+
+	offset = map__map_ip(al.map, ip);
+	if (is64bit)
+		*is64bit = dso__is_64_bit(dso);
+
+	addr_location__exit(&al);
+
+	return dso__data_read_offset(dso, machine, offset, buf, len);
+}
+
+void thread__free_stitch_list(struct thread *thread)
+{
+	struct lbr_stitch *lbr_stitch = thread__lbr_stitch(thread);
+	struct stitch_list *pos, *tmp;
+
+	if (!lbr_stitch)
+		return;
+
+	list_for_each_entry_safe(pos, tmp, &lbr_stitch->lists, node) {
+		map_symbol__exit(&pos->cursor.ms);
+		list_del_init(&pos->node);
+		free(pos);
+	}
+
+	list_for_each_entry_safe(pos, tmp, &lbr_stitch->free_lists, node) {
+		list_del_init(&pos->node);
+		free(pos);
+	}
+
+	for (unsigned int i = 0 ; i < lbr_stitch->prev_lbr_cursor_size; i++)
+		map_symbol__exit(&lbr_stitch->prev_lbr_cursor[i].ms);
+
+	zfree(&lbr_stitch->prev_lbr_cursor);
+	free(thread__lbr_stitch(thread));
+	thread__set_lbr_stitch(thread, NULL);
 }