xref: /linux/tools/perf/util/thread.c (revision cc04a46f11ea046ed53e2c832ae29e4790f7e35f)
1 #include "../perf.h"
2 #include <stdlib.h>
3 #include <stdio.h>
4 #include <string.h>
5 #include "session.h"
6 #include "thread.h"
7 #include "thread-stack.h"
8 #include "util.h"
9 #include "debug.h"
10 #include "comm.h"
11 #include "unwind.h"
12 
13 int thread__init_map_groups(struct thread *thread, struct machine *machine)
14 {
15 	struct thread *leader;
16 	pid_t pid = thread->pid_;
17 
18 	if (pid == thread->tid || pid == -1) {
19 		thread->mg = map_groups__new(machine);
20 	} else {
21 		leader = __machine__findnew_thread(machine, pid, pid);
22 		if (leader)
23 			thread->mg = map_groups__get(leader->mg);
24 	}
25 
26 	return thread->mg ? 0 : -1;
27 }
28 
29 struct thread *thread__new(pid_t pid, pid_t tid)
30 {
31 	char *comm_str;
32 	struct comm *comm;
33 	struct thread *thread = zalloc(sizeof(*thread));
34 
35 	if (thread != NULL) {
36 		thread->pid_ = pid;
37 		thread->tid = tid;
38 		thread->ppid = -1;
39 		thread->cpu = -1;
40 		INIT_LIST_HEAD(&thread->comm_list);
41 
42 		if (unwind__prepare_access(thread) < 0)
43 			goto err_thread;
44 
45 		comm_str = malloc(32);
46 		if (!comm_str)
47 			goto err_thread;
48 
49 		snprintf(comm_str, 32, ":%d", tid);
50 		comm = comm__new(comm_str, 0, false);
51 		free(comm_str);
52 		if (!comm)
53 			goto err_thread;
54 
55 		list_add(&comm->list, &thread->comm_list);
56 		atomic_set(&thread->refcnt, 0);
57 		RB_CLEAR_NODE(&thread->rb_node);
58 	}
59 
60 	return thread;
61 
62 err_thread:
63 	free(thread);
64 	return NULL;
65 }
66 
67 void thread__delete(struct thread *thread)
68 {
69 	struct comm *comm, *tmp;
70 
71 	BUG_ON(!RB_EMPTY_NODE(&thread->rb_node));
72 
73 	thread_stack__free(thread);
74 
75 	if (thread->mg) {
76 		map_groups__put(thread->mg);
77 		thread->mg = NULL;
78 	}
79 	list_for_each_entry_safe(comm, tmp, &thread->comm_list, list) {
80 		list_del(&comm->list);
81 		comm__free(comm);
82 	}
83 	unwind__finish_access(thread);
84 
85 	free(thread);
86 }
87 
88 struct thread *thread__get(struct thread *thread)
89 {
90 	if (thread)
91 		atomic_inc(&thread->refcnt);
92 	return thread;
93 }
94 
95 void thread__put(struct thread *thread)
96 {
97 	if (thread && atomic_dec_and_test(&thread->refcnt)) {
98 		list_del_init(&thread->node);
99 		thread__delete(thread);
100 	}
101 }
102 
103 struct comm *thread__comm(const struct thread *thread)
104 {
105 	if (list_empty(&thread->comm_list))
106 		return NULL;
107 
108 	return list_first_entry(&thread->comm_list, struct comm, list);
109 }
110 
111 struct comm *thread__exec_comm(const struct thread *thread)
112 {
113 	struct comm *comm, *last = NULL;
114 
115 	list_for_each_entry(comm, &thread->comm_list, list) {
116 		if (comm->exec)
117 			return comm;
118 		last = comm;
119 	}
120 
121 	return last;
122 }
123 
124 int __thread__set_comm(struct thread *thread, const char *str, u64 timestamp,
125 		       bool exec)
126 {
127 	struct comm *new, *curr = thread__comm(thread);
128 	int err;
129 
130 	/* Override the default :tid entry */
131 	if (!thread->comm_set) {
132 		err = comm__override(curr, str, timestamp, exec);
133 		if (err)
134 			return err;
135 	} else {
136 		new = comm__new(str, timestamp, exec);
137 		if (!new)
138 			return -ENOMEM;
139 		list_add(&new->list, &thread->comm_list);
140 
141 		if (exec)
142 			unwind__flush_access(thread);
143 	}
144 
145 	thread->comm_set = true;
146 
147 	return 0;
148 }
149 
150 const char *thread__comm_str(const struct thread *thread)
151 {
152 	const struct comm *comm = thread__comm(thread);
153 
154 	if (!comm)
155 		return NULL;
156 
157 	return comm__str(comm);
158 }
159 
160 /* CHECKME: it should probably better return the max comm len from its comm list */
161 int thread__comm_len(struct thread *thread)
162 {
163 	if (!thread->comm_len) {
164 		const char *comm = thread__comm_str(thread);
165 		if (!comm)
166 			return 0;
167 		thread->comm_len = strlen(comm);
168 	}
169 
170 	return thread->comm_len;
171 }
172 
173 size_t thread__fprintf(struct thread *thread, FILE *fp)
174 {
175 	return fprintf(fp, "Thread %d %s\n", thread->tid, thread__comm_str(thread)) +
176 	       map_groups__fprintf(thread->mg, fp);
177 }
178 
179 void thread__insert_map(struct thread *thread, struct map *map)
180 {
181 	map_groups__fixup_overlappings(thread->mg, map, stderr);
182 	map_groups__insert(thread->mg, map);
183 }
184 
185 static int thread__clone_map_groups(struct thread *thread,
186 				    struct thread *parent)
187 {
188 	int i;
189 
190 	/* This is new thread, we share map groups for process. */
191 	if (thread->pid_ == parent->pid_)
192 		return 0;
193 
194 	if (thread->mg == parent->mg) {
195 		pr_debug("broken map groups on thread %d/%d parent %d/%d\n",
196 			 thread->pid_, thread->tid, parent->pid_, parent->tid);
197 		return 0;
198 	}
199 
200 	/* But this one is new process, copy maps. */
201 	for (i = 0; i < MAP__NR_TYPES; ++i)
202 		if (map_groups__clone(thread->mg, parent->mg, i) < 0)
203 			return -ENOMEM;
204 
205 	return 0;
206 }
207 
208 int thread__fork(struct thread *thread, struct thread *parent, u64 timestamp)
209 {
210 	int err;
211 
212 	if (parent->comm_set) {
213 		const char *comm = thread__comm_str(parent);
214 		if (!comm)
215 			return -ENOMEM;
216 		err = thread__set_comm(thread, comm, timestamp);
217 		if (err)
218 			return err;
219 	}
220 
221 	thread->ppid = parent->tid;
222 	return thread__clone_map_groups(thread, parent);
223 }
224 
225 void thread__find_cpumode_addr_location(struct thread *thread,
226 					enum map_type type, u64 addr,
227 					struct addr_location *al)
228 {
229 	size_t i;
230 	const u8 const cpumodes[] = {
231 		PERF_RECORD_MISC_USER,
232 		PERF_RECORD_MISC_KERNEL,
233 		PERF_RECORD_MISC_GUEST_USER,
234 		PERF_RECORD_MISC_GUEST_KERNEL
235 	};
236 
237 	for (i = 0; i < ARRAY_SIZE(cpumodes); i++) {
238 		thread__find_addr_location(thread, cpumodes[i], type, addr, al);
239 		if (al->map)
240 			break;
241 	}
242 }
243