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0001 #include "callchain.h"
0002 #include "debug.h"
0003 #include "event.h"
0004 #include "evsel.h"
0005 #include "hist.h"
0006 #include "machine.h"
0007 #include "map.h"
0008 #include "sort.h"
0009 #include "strlist.h"
0010 #include "thread.h"
0011 #include "vdso.h"
0012 #include <stdbool.h>
0013 #include <symbol/kallsyms.h>
0014 #include "unwind.h"
0015 #include "linux/hash.h"
0016 
0017 static void __machine__remove_thread(struct machine *machine, struct thread *th, bool lock);
0018 
0019 static void dsos__init(struct dsos *dsos)
0020 {
0021     INIT_LIST_HEAD(&dsos->head);
0022     dsos->root = RB_ROOT;
0023     pthread_rwlock_init(&dsos->lock, NULL);
0024 }
0025 
0026 int machine__init(struct machine *machine, const char *root_dir, pid_t pid)
0027 {
0028     memset(machine, 0, sizeof(*machine));
0029     map_groups__init(&machine->kmaps, machine);
0030     RB_CLEAR_NODE(&machine->rb_node);
0031     dsos__init(&machine->dsos);
0032 
0033     machine->threads = RB_ROOT;
0034     pthread_rwlock_init(&machine->threads_lock, NULL);
0035     machine->nr_threads = 0;
0036     INIT_LIST_HEAD(&machine->dead_threads);
0037     machine->last_match = NULL;
0038 
0039     machine->vdso_info = NULL;
0040     machine->env = NULL;
0041 
0042     machine->pid = pid;
0043 
0044     machine->id_hdr_size = 0;
0045     machine->kptr_restrict_warned = false;
0046     machine->comm_exec = false;
0047     machine->kernel_start = 0;
0048 
0049     memset(machine->vmlinux_maps, 0, sizeof(machine->vmlinux_maps));
0050 
0051     machine->root_dir = strdup(root_dir);
0052     if (machine->root_dir == NULL)
0053         return -ENOMEM;
0054 
0055     if (pid != HOST_KERNEL_ID) {
0056         struct thread *thread = machine__findnew_thread(machine, -1,
0057                                 pid);
0058         char comm[64];
0059 
0060         if (thread == NULL)
0061             return -ENOMEM;
0062 
0063         snprintf(comm, sizeof(comm), "[guest/%d]", pid);
0064         thread__set_comm(thread, comm, 0);
0065         thread__put(thread);
0066     }
0067 
0068     machine->current_tid = NULL;
0069 
0070     return 0;
0071 }
0072 
0073 struct machine *machine__new_host(void)
0074 {
0075     struct machine *machine = malloc(sizeof(*machine));
0076 
0077     if (machine != NULL) {
0078         machine__init(machine, "", HOST_KERNEL_ID);
0079 
0080         if (machine__create_kernel_maps(machine) < 0)
0081             goto out_delete;
0082     }
0083 
0084     return machine;
0085 out_delete:
0086     free(machine);
0087     return NULL;
0088 }
0089 
0090 static void dsos__purge(struct dsos *dsos)
0091 {
0092     struct dso *pos, *n;
0093 
0094     pthread_rwlock_wrlock(&dsos->lock);
0095 
0096     list_for_each_entry_safe(pos, n, &dsos->head, node) {
0097         RB_CLEAR_NODE(&pos->rb_node);
0098         pos->root = NULL;
0099         list_del_init(&pos->node);
0100         dso__put(pos);
0101     }
0102 
0103     pthread_rwlock_unlock(&dsos->lock);
0104 }
0105 
0106 static void dsos__exit(struct dsos *dsos)
0107 {
0108     dsos__purge(dsos);
0109     pthread_rwlock_destroy(&dsos->lock);
0110 }
0111 
0112 void machine__delete_threads(struct machine *machine)
0113 {
0114     struct rb_node *nd;
0115 
0116     pthread_rwlock_wrlock(&machine->threads_lock);
0117     nd = rb_first(&machine->threads);
0118     while (nd) {
0119         struct thread *t = rb_entry(nd, struct thread, rb_node);
0120 
0121         nd = rb_next(nd);
0122         __machine__remove_thread(machine, t, false);
0123     }
0124     pthread_rwlock_unlock(&machine->threads_lock);
0125 }
0126 
0127 void machine__exit(struct machine *machine)
0128 {
0129     machine__destroy_kernel_maps(machine);
0130     map_groups__exit(&machine->kmaps);
0131     dsos__exit(&machine->dsos);
0132     machine__exit_vdso(machine);
0133     zfree(&machine->root_dir);
0134     zfree(&machine->current_tid);
0135     pthread_rwlock_destroy(&machine->threads_lock);
0136 }
0137 
0138 void machine__delete(struct machine *machine)
0139 {
0140     if (machine) {
0141         machine__exit(machine);
0142         free(machine);
0143     }
0144 }
0145 
0146 void machines__init(struct machines *machines)
0147 {
0148     machine__init(&machines->host, "", HOST_KERNEL_ID);
0149     machines->guests = RB_ROOT;
0150 }
0151 
0152 void machines__exit(struct machines *machines)
0153 {
0154     machine__exit(&machines->host);
0155     /* XXX exit guest */
0156 }
0157 
0158 struct machine *machines__add(struct machines *machines, pid_t pid,
0159                   const char *root_dir)
0160 {
0161     struct rb_node **p = &machines->guests.rb_node;
0162     struct rb_node *parent = NULL;
0163     struct machine *pos, *machine = malloc(sizeof(*machine));
0164 
0165     if (machine == NULL)
0166         return NULL;
0167 
0168     if (machine__init(machine, root_dir, pid) != 0) {
0169         free(machine);
0170         return NULL;
0171     }
0172 
0173     while (*p != NULL) {
0174         parent = *p;
0175         pos = rb_entry(parent, struct machine, rb_node);
0176         if (pid < pos->pid)
0177             p = &(*p)->rb_left;
0178         else
0179             p = &(*p)->rb_right;
0180     }
0181 
0182     rb_link_node(&machine->rb_node, parent, p);
0183     rb_insert_color(&machine->rb_node, &machines->guests);
0184 
0185     return machine;
0186 }
0187 
0188 void machines__set_comm_exec(struct machines *machines, bool comm_exec)
0189 {
0190     struct rb_node *nd;
0191 
0192     machines->host.comm_exec = comm_exec;
0193 
0194     for (nd = rb_first(&machines->guests); nd; nd = rb_next(nd)) {
0195         struct machine *machine = rb_entry(nd, struct machine, rb_node);
0196 
0197         machine->comm_exec = comm_exec;
0198     }
0199 }
0200 
0201 struct machine *machines__find(struct machines *machines, pid_t pid)
0202 {
0203     struct rb_node **p = &machines->guests.rb_node;
0204     struct rb_node *parent = NULL;
0205     struct machine *machine;
0206     struct machine *default_machine = NULL;
0207 
0208     if (pid == HOST_KERNEL_ID)
0209         return &machines->host;
0210 
0211     while (*p != NULL) {
0212         parent = *p;
0213         machine = rb_entry(parent, struct machine, rb_node);
0214         if (pid < machine->pid)
0215             p = &(*p)->rb_left;
0216         else if (pid > machine->pid)
0217             p = &(*p)->rb_right;
0218         else
0219             return machine;
0220         if (!machine->pid)
0221             default_machine = machine;
0222     }
0223 
0224     return default_machine;
0225 }
0226 
0227 struct machine *machines__findnew(struct machines *machines, pid_t pid)
0228 {
0229     char path[PATH_MAX];
0230     const char *root_dir = "";
0231     struct machine *machine = machines__find(machines, pid);
0232 
0233     if (machine && (machine->pid == pid))
0234         goto out;
0235 
0236     if ((pid != HOST_KERNEL_ID) &&
0237         (pid != DEFAULT_GUEST_KERNEL_ID) &&
0238         (symbol_conf.guestmount)) {
0239         sprintf(path, "%s/%d", symbol_conf.guestmount, pid);
0240         if (access(path, R_OK)) {
0241             static struct strlist *seen;
0242 
0243             if (!seen)
0244                 seen = strlist__new(NULL, NULL);
0245 
0246             if (!strlist__has_entry(seen, path)) {
0247                 pr_err("Can't access file %s\n", path);
0248                 strlist__add(seen, path);
0249             }
0250             machine = NULL;
0251             goto out;
0252         }
0253         root_dir = path;
0254     }
0255 
0256     machine = machines__add(machines, pid, root_dir);
0257 out:
0258     return machine;
0259 }
0260 
0261 void machines__process_guests(struct machines *machines,
0262                   machine__process_t process, void *data)
0263 {
0264     struct rb_node *nd;
0265 
0266     for (nd = rb_first(&machines->guests); nd; nd = rb_next(nd)) {
0267         struct machine *pos = rb_entry(nd, struct machine, rb_node);
0268         process(pos, data);
0269     }
0270 }
0271 
0272 char *machine__mmap_name(struct machine *machine, char *bf, size_t size)
0273 {
0274     if (machine__is_host(machine))
0275         snprintf(bf, size, "[%s]", "kernel.kallsyms");
0276     else if (machine__is_default_guest(machine))
0277         snprintf(bf, size, "[%s]", "guest.kernel.kallsyms");
0278     else {
0279         snprintf(bf, size, "[%s.%d]", "guest.kernel.kallsyms",
0280              machine->pid);
0281     }
0282 
0283     return bf;
0284 }
0285 
0286 void machines__set_id_hdr_size(struct machines *machines, u16 id_hdr_size)
0287 {
0288     struct rb_node *node;
0289     struct machine *machine;
0290 
0291     machines->host.id_hdr_size = id_hdr_size;
0292 
0293     for (node = rb_first(&machines->guests); node; node = rb_next(node)) {
0294         machine = rb_entry(node, struct machine, rb_node);
0295         machine->id_hdr_size = id_hdr_size;
0296     }
0297 
0298     return;
0299 }
0300 
0301 static void machine__update_thread_pid(struct machine *machine,
0302                        struct thread *th, pid_t pid)
0303 {
0304     struct thread *leader;
0305 
0306     if (pid == th->pid_ || pid == -1 || th->pid_ != -1)
0307         return;
0308 
0309     th->pid_ = pid;
0310 
0311     if (th->pid_ == th->tid)
0312         return;
0313 
0314     leader = __machine__findnew_thread(machine, th->pid_, th->pid_);
0315     if (!leader)
0316         goto out_err;
0317 
0318     if (!leader->mg)
0319         leader->mg = map_groups__new(machine);
0320 
0321     if (!leader->mg)
0322         goto out_err;
0323 
0324     if (th->mg == leader->mg)
0325         return;
0326 
0327     if (th->mg) {
0328         /*
0329          * Maps are created from MMAP events which provide the pid and
0330          * tid.  Consequently there never should be any maps on a thread
0331          * with an unknown pid.  Just print an error if there are.
0332          */
0333         if (!map_groups__empty(th->mg))
0334             pr_err("Discarding thread maps for %d:%d\n",
0335                    th->pid_, th->tid);
0336         map_groups__put(th->mg);
0337     }
0338 
0339     th->mg = map_groups__get(leader->mg);
0340 out_put:
0341     thread__put(leader);
0342     return;
0343 out_err:
0344     pr_err("Failed to join map groups for %d:%d\n", th->pid_, th->tid);
0345     goto out_put;
0346 }
0347 
0348 /*
0349  * Caller must eventually drop thread->refcnt returned with a successful
0350  * lookup/new thread inserted.
0351  */
0352 static struct thread *____machine__findnew_thread(struct machine *machine,
0353                           pid_t pid, pid_t tid,
0354                           bool create)
0355 {
0356     struct rb_node **p = &machine->threads.rb_node;
0357     struct rb_node *parent = NULL;
0358     struct thread *th;
0359 
0360     /*
0361      * Front-end cache - TID lookups come in blocks,
0362      * so most of the time we dont have to look up
0363      * the full rbtree:
0364      */
0365     th = machine->last_match;
0366     if (th != NULL) {
0367         if (th->tid == tid) {
0368             machine__update_thread_pid(machine, th, pid);
0369             return thread__get(th);
0370         }
0371 
0372         machine->last_match = NULL;
0373     }
0374 
0375     while (*p != NULL) {
0376         parent = *p;
0377         th = rb_entry(parent, struct thread, rb_node);
0378 
0379         if (th->tid == tid) {
0380             machine->last_match = th;
0381             machine__update_thread_pid(machine, th, pid);
0382             return thread__get(th);
0383         }
0384 
0385         if (tid < th->tid)
0386             p = &(*p)->rb_left;
0387         else
0388             p = &(*p)->rb_right;
0389     }
0390 
0391     if (!create)
0392         return NULL;
0393 
0394     th = thread__new(pid, tid);
0395     if (th != NULL) {
0396         rb_link_node(&th->rb_node, parent, p);
0397         rb_insert_color(&th->rb_node, &machine->threads);
0398 
0399         /*
0400          * We have to initialize map_groups separately
0401          * after rb tree is updated.
0402          *
0403          * The reason is that we call machine__findnew_thread
0404          * within thread__init_map_groups to find the thread
0405          * leader and that would screwed the rb tree.
0406          */
0407         if (thread__init_map_groups(th, machine)) {
0408             rb_erase_init(&th->rb_node, &machine->threads);
0409             RB_CLEAR_NODE(&th->rb_node);
0410             thread__put(th);
0411             return NULL;
0412         }
0413         /*
0414          * It is now in the rbtree, get a ref
0415          */
0416         thread__get(th);
0417         machine->last_match = th;
0418         ++machine->nr_threads;
0419     }
0420 
0421     return th;
0422 }
0423 
0424 struct thread *__machine__findnew_thread(struct machine *machine, pid_t pid, pid_t tid)
0425 {
0426     return ____machine__findnew_thread(machine, pid, tid, true);
0427 }
0428 
0429 struct thread *machine__findnew_thread(struct machine *machine, pid_t pid,
0430                        pid_t tid)
0431 {
0432     struct thread *th;
0433 
0434     pthread_rwlock_wrlock(&machine->threads_lock);
0435     th = __machine__findnew_thread(machine, pid, tid);
0436     pthread_rwlock_unlock(&machine->threads_lock);
0437     return th;
0438 }
0439 
0440 struct thread *machine__find_thread(struct machine *machine, pid_t pid,
0441                     pid_t tid)
0442 {
0443     struct thread *th;
0444     pthread_rwlock_rdlock(&machine->threads_lock);
0445     th =  ____machine__findnew_thread(machine, pid, tid, false);
0446     pthread_rwlock_unlock(&machine->threads_lock);
0447     return th;
0448 }
0449 
0450 struct comm *machine__thread_exec_comm(struct machine *machine,
0451                        struct thread *thread)
0452 {
0453     if (machine->comm_exec)
0454         return thread__exec_comm(thread);
0455     else
0456         return thread__comm(thread);
0457 }
0458 
0459 int machine__process_comm_event(struct machine *machine, union perf_event *event,
0460                 struct perf_sample *sample)
0461 {
0462     struct thread *thread = machine__findnew_thread(machine,
0463                             event->comm.pid,
0464                             event->comm.tid);
0465     bool exec = event->header.misc & PERF_RECORD_MISC_COMM_EXEC;
0466     int err = 0;
0467 
0468     if (exec)
0469         machine->comm_exec = true;
0470 
0471     if (dump_trace)
0472         perf_event__fprintf_comm(event, stdout);
0473 
0474     if (thread == NULL ||
0475         __thread__set_comm(thread, event->comm.comm, sample->time, exec)) {
0476         dump_printf("problem processing PERF_RECORD_COMM, skipping event.\n");
0477         err = -1;
0478     }
0479 
0480     thread__put(thread);
0481 
0482     return err;
0483 }
0484 
0485 int machine__process_lost_event(struct machine *machine __maybe_unused,
0486                 union perf_event *event, struct perf_sample *sample __maybe_unused)
0487 {
0488     dump_printf(": id:%" PRIu64 ": lost:%" PRIu64 "\n",
0489             event->lost.id, event->lost.lost);
0490     return 0;
0491 }
0492 
0493 int machine__process_lost_samples_event(struct machine *machine __maybe_unused,
0494                     union perf_event *event, struct perf_sample *sample)
0495 {
0496     dump_printf(": id:%" PRIu64 ": lost samples :%" PRIu64 "\n",
0497             sample->id, event->lost_samples.lost);
0498     return 0;
0499 }
0500 
0501 static struct dso *machine__findnew_module_dso(struct machine *machine,
0502                            struct kmod_path *m,
0503                            const char *filename)
0504 {
0505     struct dso *dso;
0506 
0507     pthread_rwlock_wrlock(&machine->dsos.lock);
0508 
0509     dso = __dsos__find(&machine->dsos, m->name, true);
0510     if (!dso) {
0511         dso = __dsos__addnew(&machine->dsos, m->name);
0512         if (dso == NULL)
0513             goto out_unlock;
0514 
0515         if (machine__is_host(machine))
0516             dso->symtab_type = DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE;
0517         else
0518             dso->symtab_type = DSO_BINARY_TYPE__GUEST_KMODULE;
0519 
0520         /* _KMODULE_COMP should be next to _KMODULE */
0521         if (m->kmod && m->comp)
0522             dso->symtab_type++;
0523 
0524         dso__set_short_name(dso, strdup(m->name), true);
0525         dso__set_long_name(dso, strdup(filename), true);
0526     }
0527 
0528     dso__get(dso);
0529 out_unlock:
0530     pthread_rwlock_unlock(&machine->dsos.lock);
0531     return dso;
0532 }
0533 
0534 int machine__process_aux_event(struct machine *machine __maybe_unused,
0535                    union perf_event *event)
0536 {
0537     if (dump_trace)
0538         perf_event__fprintf_aux(event, stdout);
0539     return 0;
0540 }
0541 
0542 int machine__process_itrace_start_event(struct machine *machine __maybe_unused,
0543                     union perf_event *event)
0544 {
0545     if (dump_trace)
0546         perf_event__fprintf_itrace_start(event, stdout);
0547     return 0;
0548 }
0549 
0550 int machine__process_switch_event(struct machine *machine __maybe_unused,
0551                   union perf_event *event)
0552 {
0553     if (dump_trace)
0554         perf_event__fprintf_switch(event, stdout);
0555     return 0;
0556 }
0557 
0558 static void dso__adjust_kmod_long_name(struct dso *dso, const char *filename)
0559 {
0560     const char *dup_filename;
0561 
0562     if (!filename || !dso || !dso->long_name)
0563         return;
0564     if (dso->long_name[0] != '[')
0565         return;
0566     if (!strchr(filename, '/'))
0567         return;
0568 
0569     dup_filename = strdup(filename);
0570     if (!dup_filename)
0571         return;
0572 
0573     dso__set_long_name(dso, dup_filename, true);
0574 }
0575 
0576 struct map *machine__findnew_module_map(struct machine *machine, u64 start,
0577                     const char *filename)
0578 {
0579     struct map *map = NULL;
0580     struct dso *dso = NULL;
0581     struct kmod_path m;
0582 
0583     if (kmod_path__parse_name(&m, filename))
0584         return NULL;
0585 
0586     map = map_groups__find_by_name(&machine->kmaps, MAP__FUNCTION,
0587                        m.name);
0588     if (map) {
0589         /*
0590          * If the map's dso is an offline module, give dso__load()
0591          * a chance to find the file path of that module by fixing
0592          * long_name.
0593          */
0594         dso__adjust_kmod_long_name(map->dso, filename);
0595         goto out;
0596     }
0597 
0598     dso = machine__findnew_module_dso(machine, &m, filename);
0599     if (dso == NULL)
0600         goto out;
0601 
0602     map = map__new2(start, dso, MAP__FUNCTION);
0603     if (map == NULL)
0604         goto out;
0605 
0606     map_groups__insert(&machine->kmaps, map);
0607 
0608     /* Put the map here because map_groups__insert alread got it */
0609     map__put(map);
0610 out:
0611     /* put the dso here, corresponding to  machine__findnew_module_dso */
0612     dso__put(dso);
0613     free(m.name);
0614     return map;
0615 }
0616 
0617 size_t machines__fprintf_dsos(struct machines *machines, FILE *fp)
0618 {
0619     struct rb_node *nd;
0620     size_t ret = __dsos__fprintf(&machines->host.dsos.head, fp);
0621 
0622     for (nd = rb_first(&machines->guests); nd; nd = rb_next(nd)) {
0623         struct machine *pos = rb_entry(nd, struct machine, rb_node);
0624         ret += __dsos__fprintf(&pos->dsos.head, fp);
0625     }
0626 
0627     return ret;
0628 }
0629 
0630 size_t machine__fprintf_dsos_buildid(struct machine *m, FILE *fp,
0631                      bool (skip)(struct dso *dso, int parm), int parm)
0632 {
0633     return __dsos__fprintf_buildid(&m->dsos.head, fp, skip, parm);
0634 }
0635 
0636 size_t machines__fprintf_dsos_buildid(struct machines *machines, FILE *fp,
0637                      bool (skip)(struct dso *dso, int parm), int parm)
0638 {
0639     struct rb_node *nd;
0640     size_t ret = machine__fprintf_dsos_buildid(&machines->host, fp, skip, parm);
0641 
0642     for (nd = rb_first(&machines->guests); nd; nd = rb_next(nd)) {
0643         struct machine *pos = rb_entry(nd, struct machine, rb_node);
0644         ret += machine__fprintf_dsos_buildid(pos, fp, skip, parm);
0645     }
0646     return ret;
0647 }
0648 
0649 size_t machine__fprintf_vmlinux_path(struct machine *machine, FILE *fp)
0650 {
0651     int i;
0652     size_t printed = 0;
0653     struct dso *kdso = machine__kernel_map(machine)->dso;
0654 
0655     if (kdso->has_build_id) {
0656         char filename[PATH_MAX];
0657         if (dso__build_id_filename(kdso, filename, sizeof(filename)))
0658             printed += fprintf(fp, "[0] %s\n", filename);
0659     }
0660 
0661     for (i = 0; i < vmlinux_path__nr_entries; ++i)
0662         printed += fprintf(fp, "[%d] %s\n",
0663                    i + kdso->has_build_id, vmlinux_path[i]);
0664 
0665     return printed;
0666 }
0667 
0668 size_t machine__fprintf(struct machine *machine, FILE *fp)
0669 {
0670     size_t ret;
0671     struct rb_node *nd;
0672 
0673     pthread_rwlock_rdlock(&machine->threads_lock);
0674 
0675     ret = fprintf(fp, "Threads: %u\n", machine->nr_threads);
0676 
0677     for (nd = rb_first(&machine->threads); nd; nd = rb_next(nd)) {
0678         struct thread *pos = rb_entry(nd, struct thread, rb_node);
0679 
0680         ret += thread__fprintf(pos, fp);
0681     }
0682 
0683     pthread_rwlock_unlock(&machine->threads_lock);
0684 
0685     return ret;
0686 }
0687 
0688 static struct dso *machine__get_kernel(struct machine *machine)
0689 {
0690     const char *vmlinux_name = NULL;
0691     struct dso *kernel;
0692 
0693     if (machine__is_host(machine)) {
0694         vmlinux_name = symbol_conf.vmlinux_name;
0695         if (!vmlinux_name)
0696             vmlinux_name = DSO__NAME_KALLSYMS;
0697 
0698         kernel = machine__findnew_kernel(machine, vmlinux_name,
0699                          "[kernel]", DSO_TYPE_KERNEL);
0700     } else {
0701         char bf[PATH_MAX];
0702 
0703         if (machine__is_default_guest(machine))
0704             vmlinux_name = symbol_conf.default_guest_vmlinux_name;
0705         if (!vmlinux_name)
0706             vmlinux_name = machine__mmap_name(machine, bf,
0707                               sizeof(bf));
0708 
0709         kernel = machine__findnew_kernel(machine, vmlinux_name,
0710                          "[guest.kernel]",
0711                          DSO_TYPE_GUEST_KERNEL);
0712     }
0713 
0714     if (kernel != NULL && (!kernel->has_build_id))
0715         dso__read_running_kernel_build_id(kernel, machine);
0716 
0717     return kernel;
0718 }
0719 
0720 struct process_args {
0721     u64 start;
0722 };
0723 
0724 static void machine__get_kallsyms_filename(struct machine *machine, char *buf,
0725                        size_t bufsz)
0726 {
0727     if (machine__is_default_guest(machine))
0728         scnprintf(buf, bufsz, "%s", symbol_conf.default_guest_kallsyms);
0729     else
0730         scnprintf(buf, bufsz, "%s/proc/kallsyms", machine->root_dir);
0731 }
0732 
0733 const char *ref_reloc_sym_names[] = {"_text", "_stext", NULL};
0734 
0735 /* Figure out the start address of kernel map from /proc/kallsyms.
0736  * Returns the name of the start symbol in *symbol_name. Pass in NULL as
0737  * symbol_name if it's not that important.
0738  */
0739 static u64 machine__get_running_kernel_start(struct machine *machine,
0740                          const char **symbol_name)
0741 {
0742     char filename[PATH_MAX];
0743     int i;
0744     const char *name;
0745     u64 addr = 0;
0746 
0747     machine__get_kallsyms_filename(machine, filename, PATH_MAX);
0748 
0749     if (symbol__restricted_filename(filename, "/proc/kallsyms"))
0750         return 0;
0751 
0752     for (i = 0; (name = ref_reloc_sym_names[i]) != NULL; i++) {
0753         addr = kallsyms__get_function_start(filename, name);
0754         if (addr)
0755             break;
0756     }
0757 
0758     if (symbol_name)
0759         *symbol_name = name;
0760 
0761     return addr;
0762 }
0763 
0764 int __machine__create_kernel_maps(struct machine *machine, struct dso *kernel)
0765 {
0766     enum map_type type;
0767     u64 start = machine__get_running_kernel_start(machine, NULL);
0768 
0769     /* In case of renewal the kernel map, destroy previous one */
0770     machine__destroy_kernel_maps(machine);
0771 
0772     for (type = 0; type < MAP__NR_TYPES; ++type) {
0773         struct kmap *kmap;
0774         struct map *map;
0775 
0776         machine->vmlinux_maps[type] = map__new2(start, kernel, type);
0777         if (machine->vmlinux_maps[type] == NULL)
0778             return -1;
0779 
0780         machine->vmlinux_maps[type]->map_ip =
0781             machine->vmlinux_maps[type]->unmap_ip =
0782                 identity__map_ip;
0783         map = __machine__kernel_map(machine, type);
0784         kmap = map__kmap(map);
0785         if (!kmap)
0786             return -1;
0787 
0788         kmap->kmaps = &machine->kmaps;
0789         map_groups__insert(&machine->kmaps, map);
0790     }
0791 
0792     return 0;
0793 }
0794 
0795 void machine__destroy_kernel_maps(struct machine *machine)
0796 {
0797     enum map_type type;
0798 
0799     for (type = 0; type < MAP__NR_TYPES; ++type) {
0800         struct kmap *kmap;
0801         struct map *map = __machine__kernel_map(machine, type);
0802 
0803         if (map == NULL)
0804             continue;
0805 
0806         kmap = map__kmap(map);
0807         map_groups__remove(&machine->kmaps, map);
0808         if (kmap && kmap->ref_reloc_sym) {
0809             /*
0810              * ref_reloc_sym is shared among all maps, so free just
0811              * on one of them.
0812              */
0813             if (type == MAP__FUNCTION) {
0814                 zfree((char **)&kmap->ref_reloc_sym->name);
0815                 zfree(&kmap->ref_reloc_sym);
0816             } else
0817                 kmap->ref_reloc_sym = NULL;
0818         }
0819 
0820         map__put(machine->vmlinux_maps[type]);
0821         machine->vmlinux_maps[type] = NULL;
0822     }
0823 }
0824 
0825 int machines__create_guest_kernel_maps(struct machines *machines)
0826 {
0827     int ret = 0;
0828     struct dirent **namelist = NULL;
0829     int i, items = 0;
0830     char path[PATH_MAX];
0831     pid_t pid;
0832     char *endp;
0833 
0834     if (symbol_conf.default_guest_vmlinux_name ||
0835         symbol_conf.default_guest_modules ||
0836         symbol_conf.default_guest_kallsyms) {
0837         machines__create_kernel_maps(machines, DEFAULT_GUEST_KERNEL_ID);
0838     }
0839 
0840     if (symbol_conf.guestmount) {
0841         items = scandir(symbol_conf.guestmount, &namelist, NULL, NULL);
0842         if (items <= 0)
0843             return -ENOENT;
0844         for (i = 0; i < items; i++) {
0845             if (!isdigit(namelist[i]->d_name[0])) {
0846                 /* Filter out . and .. */
0847                 continue;
0848             }
0849             pid = (pid_t)strtol(namelist[i]->d_name, &endp, 10);
0850             if ((*endp != '\0') ||
0851                 (endp == namelist[i]->d_name) ||
0852                 (errno == ERANGE)) {
0853                 pr_debug("invalid directory (%s). Skipping.\n",
0854                      namelist[i]->d_name);
0855                 continue;
0856             }
0857             sprintf(path, "%s/%s/proc/kallsyms",
0858                 symbol_conf.guestmount,
0859                 namelist[i]->d_name);
0860             ret = access(path, R_OK);
0861             if (ret) {
0862                 pr_debug("Can't access file %s\n", path);
0863                 goto failure;
0864             }
0865             machines__create_kernel_maps(machines, pid);
0866         }
0867 failure:
0868         free(namelist);
0869     }
0870 
0871     return ret;
0872 }
0873 
0874 void machines__destroy_kernel_maps(struct machines *machines)
0875 {
0876     struct rb_node *next = rb_first(&machines->guests);
0877 
0878     machine__destroy_kernel_maps(&machines->host);
0879 
0880     while (next) {
0881         struct machine *pos = rb_entry(next, struct machine, rb_node);
0882 
0883         next = rb_next(&pos->rb_node);
0884         rb_erase(&pos->rb_node, &machines->guests);
0885         machine__delete(pos);
0886     }
0887 }
0888 
0889 int machines__create_kernel_maps(struct machines *machines, pid_t pid)
0890 {
0891     struct machine *machine = machines__findnew(machines, pid);
0892 
0893     if (machine == NULL)
0894         return -1;
0895 
0896     return machine__create_kernel_maps(machine);
0897 }
0898 
0899 int __machine__load_kallsyms(struct machine *machine, const char *filename,
0900                  enum map_type type, bool no_kcore)
0901 {
0902     struct map *map = machine__kernel_map(machine);
0903     int ret = __dso__load_kallsyms(map->dso, filename, map, no_kcore);
0904 
0905     if (ret > 0) {
0906         dso__set_loaded(map->dso, type);
0907         /*
0908          * Since /proc/kallsyms will have multiple sessions for the
0909          * kernel, with modules between them, fixup the end of all
0910          * sections.
0911          */
0912         __map_groups__fixup_end(&machine->kmaps, type);
0913     }
0914 
0915     return ret;
0916 }
0917 
0918 int machine__load_kallsyms(struct machine *machine, const char *filename,
0919                enum map_type type)
0920 {
0921     return __machine__load_kallsyms(machine, filename, type, false);
0922 }
0923 
0924 int machine__load_vmlinux_path(struct machine *machine, enum map_type type)
0925 {
0926     struct map *map = machine__kernel_map(machine);
0927     int ret = dso__load_vmlinux_path(map->dso, map);
0928 
0929     if (ret > 0)
0930         dso__set_loaded(map->dso, type);
0931 
0932     return ret;
0933 }
0934 
0935 static void map_groups__fixup_end(struct map_groups *mg)
0936 {
0937     int i;
0938     for (i = 0; i < MAP__NR_TYPES; ++i)
0939         __map_groups__fixup_end(mg, i);
0940 }
0941 
0942 static char *get_kernel_version(const char *root_dir)
0943 {
0944     char version[PATH_MAX];
0945     FILE *file;
0946     char *name, *tmp;
0947     const char *prefix = "Linux version ";
0948 
0949     sprintf(version, "%s/proc/version", root_dir);
0950     file = fopen(version, "r");
0951     if (!file)
0952         return NULL;
0953 
0954     version[0] = '\0';
0955     tmp = fgets(version, sizeof(version), file);
0956     fclose(file);
0957 
0958     name = strstr(version, prefix);
0959     if (!name)
0960         return NULL;
0961     name += strlen(prefix);
0962     tmp = strchr(name, ' ');
0963     if (tmp)
0964         *tmp = '\0';
0965 
0966     return strdup(name);
0967 }
0968 
0969 static bool is_kmod_dso(struct dso *dso)
0970 {
0971     return dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
0972            dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE;
0973 }
0974 
0975 static int map_groups__set_module_path(struct map_groups *mg, const char *path,
0976                        struct kmod_path *m)
0977 {
0978     struct map *map;
0979     char *long_name;
0980 
0981     map = map_groups__find_by_name(mg, MAP__FUNCTION, m->name);
0982     if (map == NULL)
0983         return 0;
0984 
0985     long_name = strdup(path);
0986     if (long_name == NULL)
0987         return -ENOMEM;
0988 
0989     dso__set_long_name(map->dso, long_name, true);
0990     dso__kernel_module_get_build_id(map->dso, "");
0991 
0992     /*
0993      * Full name could reveal us kmod compression, so
0994      * we need to update the symtab_type if needed.
0995      */
0996     if (m->comp && is_kmod_dso(map->dso))
0997         map->dso->symtab_type++;
0998 
0999     return 0;
1000 }
1001 
1002 static int map_groups__set_modules_path_dir(struct map_groups *mg,
1003                 const char *dir_name, int depth)
1004 {
1005     struct dirent *dent;
1006     DIR *dir = opendir(dir_name);
1007     int ret = 0;
1008 
1009     if (!dir) {
1010         pr_debug("%s: cannot open %s dir\n", __func__, dir_name);
1011         return -1;
1012     }
1013 
1014     while ((dent = readdir(dir)) != NULL) {
1015         char path[PATH_MAX];
1016         struct stat st;
1017 
1018         /*sshfs might return bad dent->d_type, so we have to stat*/
1019         snprintf(path, sizeof(path), "%s/%s", dir_name, dent->d_name);
1020         if (stat(path, &st))
1021             continue;
1022 
1023         if (S_ISDIR(st.st_mode)) {
1024             if (!strcmp(dent->d_name, ".") ||
1025                 !strcmp(dent->d_name, ".."))
1026                 continue;
1027 
1028             /* Do not follow top-level source and build symlinks */
1029             if (depth == 0) {
1030                 if (!strcmp(dent->d_name, "source") ||
1031                     !strcmp(dent->d_name, "build"))
1032                     continue;
1033             }
1034 
1035             ret = map_groups__set_modules_path_dir(mg, path,
1036                                    depth + 1);
1037             if (ret < 0)
1038                 goto out;
1039         } else {
1040             struct kmod_path m;
1041 
1042             ret = kmod_path__parse_name(&m, dent->d_name);
1043             if (ret)
1044                 goto out;
1045 
1046             if (m.kmod)
1047                 ret = map_groups__set_module_path(mg, path, &m);
1048 
1049             free(m.name);
1050 
1051             if (ret)
1052                 goto out;
1053         }
1054     }
1055 
1056 out:
1057     closedir(dir);
1058     return ret;
1059 }
1060 
1061 static int machine__set_modules_path(struct machine *machine)
1062 {
1063     char *version;
1064     char modules_path[PATH_MAX];
1065 
1066     version = get_kernel_version(machine->root_dir);
1067     if (!version)
1068         return -1;
1069 
1070     snprintf(modules_path, sizeof(modules_path), "%s/lib/modules/%s",
1071          machine->root_dir, version);
1072     free(version);
1073 
1074     return map_groups__set_modules_path_dir(&machine->kmaps, modules_path, 0);
1075 }
1076 int __weak arch__fix_module_text_start(u64 *start __maybe_unused,
1077                 const char *name __maybe_unused)
1078 {
1079     return 0;
1080 }
1081 
1082 static int machine__create_module(void *arg, const char *name, u64 start)
1083 {
1084     struct machine *machine = arg;
1085     struct map *map;
1086 
1087     if (arch__fix_module_text_start(&start, name) < 0)
1088         return -1;
1089 
1090     map = machine__findnew_module_map(machine, start, name);
1091     if (map == NULL)
1092         return -1;
1093 
1094     dso__kernel_module_get_build_id(map->dso, machine->root_dir);
1095 
1096     return 0;
1097 }
1098 
1099 static int machine__create_modules(struct machine *machine)
1100 {
1101     const char *modules;
1102     char path[PATH_MAX];
1103 
1104     if (machine__is_default_guest(machine)) {
1105         modules = symbol_conf.default_guest_modules;
1106     } else {
1107         snprintf(path, PATH_MAX, "%s/proc/modules", machine->root_dir);
1108         modules = path;
1109     }
1110 
1111     if (symbol__restricted_filename(modules, "/proc/modules"))
1112         return -1;
1113 
1114     if (modules__parse(modules, machine, machine__create_module))
1115         return -1;
1116 
1117     if (!machine__set_modules_path(machine))
1118         return 0;
1119 
1120     pr_debug("Problems setting modules path maps, continuing anyway...\n");
1121 
1122     return 0;
1123 }
1124 
1125 int machine__create_kernel_maps(struct machine *machine)
1126 {
1127     struct dso *kernel = machine__get_kernel(machine);
1128     const char *name;
1129     u64 addr;
1130     int ret;
1131 
1132     if (kernel == NULL)
1133         return -1;
1134 
1135     ret = __machine__create_kernel_maps(machine, kernel);
1136     dso__put(kernel);
1137     if (ret < 0)
1138         return -1;
1139 
1140     if (symbol_conf.use_modules && machine__create_modules(machine) < 0) {
1141         if (machine__is_host(machine))
1142             pr_debug("Problems creating module maps, "
1143                  "continuing anyway...\n");
1144         else
1145             pr_debug("Problems creating module maps for guest %d, "
1146                  "continuing anyway...\n", machine->pid);
1147     }
1148 
1149     /*
1150      * Now that we have all the maps created, just set the ->end of them:
1151      */
1152     map_groups__fixup_end(&machine->kmaps);
1153 
1154     addr = machine__get_running_kernel_start(machine, &name);
1155     if (!addr) {
1156     } else if (maps__set_kallsyms_ref_reloc_sym(machine->vmlinux_maps, name, addr)) {
1157         machine__destroy_kernel_maps(machine);
1158         return -1;
1159     }
1160 
1161     return 0;
1162 }
1163 
1164 static void machine__set_kernel_mmap_len(struct machine *machine,
1165                      union perf_event *event)
1166 {
1167     int i;
1168 
1169     for (i = 0; i < MAP__NR_TYPES; i++) {
1170         machine->vmlinux_maps[i]->start = event->mmap.start;
1171         machine->vmlinux_maps[i]->end   = (event->mmap.start +
1172                            event->mmap.len);
1173         /*
1174          * Be a bit paranoid here, some perf.data file came with
1175          * a zero sized synthesized MMAP event for the kernel.
1176          */
1177         if (machine->vmlinux_maps[i]->end == 0)
1178             machine->vmlinux_maps[i]->end = ~0ULL;
1179     }
1180 }
1181 
1182 static bool machine__uses_kcore(struct machine *machine)
1183 {
1184     struct dso *dso;
1185 
1186     list_for_each_entry(dso, &machine->dsos.head, node) {
1187         if (dso__is_kcore(dso))
1188             return true;
1189     }
1190 
1191     return false;
1192 }
1193 
1194 static int machine__process_kernel_mmap_event(struct machine *machine,
1195                           union perf_event *event)
1196 {
1197     struct map *map;
1198     char kmmap_prefix[PATH_MAX];
1199     enum dso_kernel_type kernel_type;
1200     bool is_kernel_mmap;
1201 
1202     /* If we have maps from kcore then we do not need or want any others */
1203     if (machine__uses_kcore(machine))
1204         return 0;
1205 
1206     machine__mmap_name(machine, kmmap_prefix, sizeof(kmmap_prefix));
1207     if (machine__is_host(machine))
1208         kernel_type = DSO_TYPE_KERNEL;
1209     else
1210         kernel_type = DSO_TYPE_GUEST_KERNEL;
1211 
1212     is_kernel_mmap = memcmp(event->mmap.filename,
1213                 kmmap_prefix,
1214                 strlen(kmmap_prefix) - 1) == 0;
1215     if (event->mmap.filename[0] == '/' ||
1216         (!is_kernel_mmap && event->mmap.filename[0] == '[')) {
1217         map = machine__findnew_module_map(machine, event->mmap.start,
1218                           event->mmap.filename);
1219         if (map == NULL)
1220             goto out_problem;
1221 
1222         map->end = map->start + event->mmap.len;
1223     } else if (is_kernel_mmap) {
1224         const char *symbol_name = (event->mmap.filename +
1225                 strlen(kmmap_prefix));
1226         /*
1227          * Should be there already, from the build-id table in
1228          * the header.
1229          */
1230         struct dso *kernel = NULL;
1231         struct dso *dso;
1232 
1233         pthread_rwlock_rdlock(&machine->dsos.lock);
1234 
1235         list_for_each_entry(dso, &machine->dsos.head, node) {
1236 
1237             /*
1238              * The cpumode passed to is_kernel_module is not the
1239              * cpumode of *this* event. If we insist on passing
1240              * correct cpumode to is_kernel_module, we should
1241              * record the cpumode when we adding this dso to the
1242              * linked list.
1243              *
1244              * However we don't really need passing correct
1245              * cpumode.  We know the correct cpumode must be kernel
1246              * mode (if not, we should not link it onto kernel_dsos
1247              * list).
1248              *
1249              * Therefore, we pass PERF_RECORD_MISC_CPUMODE_UNKNOWN.
1250              * is_kernel_module() treats it as a kernel cpumode.
1251              */
1252 
1253             if (!dso->kernel ||
1254                 is_kernel_module(dso->long_name,
1255                          PERF_RECORD_MISC_CPUMODE_UNKNOWN))
1256                 continue;
1257 
1258 
1259             kernel = dso;
1260             break;
1261         }
1262 
1263         pthread_rwlock_unlock(&machine->dsos.lock);
1264 
1265         if (kernel == NULL)
1266             kernel = machine__findnew_dso(machine, kmmap_prefix);
1267         if (kernel == NULL)
1268             goto out_problem;
1269 
1270         kernel->kernel = kernel_type;
1271         if (__machine__create_kernel_maps(machine, kernel) < 0) {
1272             dso__put(kernel);
1273             goto out_problem;
1274         }
1275 
1276         if (strstr(kernel->long_name, "vmlinux"))
1277             dso__set_short_name(kernel, "[kernel.vmlinux]", false);
1278 
1279         machine__set_kernel_mmap_len(machine, event);
1280 
1281         /*
1282          * Avoid using a zero address (kptr_restrict) for the ref reloc
1283          * symbol. Effectively having zero here means that at record
1284          * time /proc/sys/kernel/kptr_restrict was non zero.
1285          */
1286         if (event->mmap.pgoff != 0) {
1287             maps__set_kallsyms_ref_reloc_sym(machine->vmlinux_maps,
1288                              symbol_name,
1289                              event->mmap.pgoff);
1290         }
1291 
1292         if (machine__is_default_guest(machine)) {
1293             /*
1294              * preload dso of guest kernel and modules
1295              */
1296             dso__load(kernel, machine__kernel_map(machine));
1297         }
1298     }
1299     return 0;
1300 out_problem:
1301     return -1;
1302 }
1303 
1304 int machine__process_mmap2_event(struct machine *machine,
1305                  union perf_event *event,
1306                  struct perf_sample *sample)
1307 {
1308     struct thread *thread;
1309     struct map *map;
1310     enum map_type type;
1311     int ret = 0;
1312 
1313     if (dump_trace)
1314         perf_event__fprintf_mmap2(event, stdout);
1315 
1316     if (sample->cpumode == PERF_RECORD_MISC_GUEST_KERNEL ||
1317         sample->cpumode == PERF_RECORD_MISC_KERNEL) {
1318         ret = machine__process_kernel_mmap_event(machine, event);
1319         if (ret < 0)
1320             goto out_problem;
1321         return 0;
1322     }
1323 
1324     thread = machine__findnew_thread(machine, event->mmap2.pid,
1325                     event->mmap2.tid);
1326     if (thread == NULL)
1327         goto out_problem;
1328 
1329     if (event->header.misc & PERF_RECORD_MISC_MMAP_DATA)
1330         type = MAP__VARIABLE;
1331     else
1332         type = MAP__FUNCTION;
1333 
1334     map = map__new(machine, event->mmap2.start,
1335             event->mmap2.len, event->mmap2.pgoff,
1336             event->mmap2.pid, event->mmap2.maj,
1337             event->mmap2.min, event->mmap2.ino,
1338             event->mmap2.ino_generation,
1339             event->mmap2.prot,
1340             event->mmap2.flags,
1341             event->mmap2.filename, type, thread);
1342 
1343     if (map == NULL)
1344         goto out_problem_map;
1345 
1346     ret = thread__insert_map(thread, map);
1347     if (ret)
1348         goto out_problem_insert;
1349 
1350     thread__put(thread);
1351     map__put(map);
1352     return 0;
1353 
1354 out_problem_insert:
1355     map__put(map);
1356 out_problem_map:
1357     thread__put(thread);
1358 out_problem:
1359     dump_printf("problem processing PERF_RECORD_MMAP2, skipping event.\n");
1360     return 0;
1361 }
1362 
1363 int machine__process_mmap_event(struct machine *machine, union perf_event *event,
1364                 struct perf_sample *sample)
1365 {
1366     struct thread *thread;
1367     struct map *map;
1368     enum map_type type;
1369     int ret = 0;
1370 
1371     if (dump_trace)
1372         perf_event__fprintf_mmap(event, stdout);
1373 
1374     if (sample->cpumode == PERF_RECORD_MISC_GUEST_KERNEL ||
1375         sample->cpumode == PERF_RECORD_MISC_KERNEL) {
1376         ret = machine__process_kernel_mmap_event(machine, event);
1377         if (ret < 0)
1378             goto out_problem;
1379         return 0;
1380     }
1381 
1382     thread = machine__findnew_thread(machine, event->mmap.pid,
1383                      event->mmap.tid);
1384     if (thread == NULL)
1385         goto out_problem;
1386 
1387     if (event->header.misc & PERF_RECORD_MISC_MMAP_DATA)
1388         type = MAP__VARIABLE;
1389     else
1390         type = MAP__FUNCTION;
1391 
1392     map = map__new(machine, event->mmap.start,
1393             event->mmap.len, event->mmap.pgoff,
1394             event->mmap.pid, 0, 0, 0, 0, 0, 0,
1395             event->mmap.filename,
1396             type, thread);
1397 
1398     if (map == NULL)
1399         goto out_problem_map;
1400 
1401     ret = thread__insert_map(thread, map);
1402     if (ret)
1403         goto out_problem_insert;
1404 
1405     thread__put(thread);
1406     map__put(map);
1407     return 0;
1408 
1409 out_problem_insert:
1410     map__put(map);
1411 out_problem_map:
1412     thread__put(thread);
1413 out_problem:
1414     dump_printf("problem processing PERF_RECORD_MMAP, skipping event.\n");
1415     return 0;
1416 }
1417 
1418 static void __machine__remove_thread(struct machine *machine, struct thread *th, bool lock)
1419 {
1420     if (machine->last_match == th)
1421         machine->last_match = NULL;
1422 
1423     BUG_ON(atomic_read(&th->refcnt) == 0);
1424     if (lock)
1425         pthread_rwlock_wrlock(&machine->threads_lock);
1426     rb_erase_init(&th->rb_node, &machine->threads);
1427     RB_CLEAR_NODE(&th->rb_node);
1428     --machine->nr_threads;
1429     /*
1430      * Move it first to the dead_threads list, then drop the reference,
1431      * if this is the last reference, then the thread__delete destructor
1432      * will be called and we will remove it from the dead_threads list.
1433      */
1434     list_add_tail(&th->node, &machine->dead_threads);
1435     if (lock)
1436         pthread_rwlock_unlock(&machine->threads_lock);
1437     thread__put(th);
1438 }
1439 
1440 void machine__remove_thread(struct machine *machine, struct thread *th)
1441 {
1442     return __machine__remove_thread(machine, th, true);
1443 }
1444 
1445 int machine__process_fork_event(struct machine *machine, union perf_event *event,
1446                 struct perf_sample *sample)
1447 {
1448     struct thread *thread = machine__find_thread(machine,
1449                              event->fork.pid,
1450                              event->fork.tid);
1451     struct thread *parent = machine__findnew_thread(machine,
1452                             event->fork.ppid,
1453                             event->fork.ptid);
1454     int err = 0;
1455 
1456     if (dump_trace)
1457         perf_event__fprintf_task(event, stdout);
1458 
1459     /*
1460      * There may be an existing thread that is not actually the parent,
1461      * either because we are processing events out of order, or because the
1462      * (fork) event that would have removed the thread was lost. Assume the
1463      * latter case and continue on as best we can.
1464      */
1465     if (parent->pid_ != (pid_t)event->fork.ppid) {
1466         dump_printf("removing erroneous parent thread %d/%d\n",
1467                 parent->pid_, parent->tid);
1468         machine__remove_thread(machine, parent);
1469         thread__put(parent);
1470         parent = machine__findnew_thread(machine, event->fork.ppid,
1471                          event->fork.ptid);
1472     }
1473 
1474     /* if a thread currently exists for the thread id remove it */
1475     if (thread != NULL) {
1476         machine__remove_thread(machine, thread);
1477         thread__put(thread);
1478     }
1479 
1480     thread = machine__findnew_thread(machine, event->fork.pid,
1481                      event->fork.tid);
1482 
1483     if (thread == NULL || parent == NULL ||
1484         thread__fork(thread, parent, sample->time) < 0) {
1485         dump_printf("problem processing PERF_RECORD_FORK, skipping event.\n");
1486         err = -1;
1487     }
1488     thread__put(thread);
1489     thread__put(parent);
1490 
1491     return err;
1492 }
1493 
1494 int machine__process_exit_event(struct machine *machine, union perf_event *event,
1495                 struct perf_sample *sample __maybe_unused)
1496 {
1497     struct thread *thread = machine__find_thread(machine,
1498                              event->fork.pid,
1499                              event->fork.tid);
1500 
1501     if (dump_trace)
1502         perf_event__fprintf_task(event, stdout);
1503 
1504     if (thread != NULL) {
1505         thread__exited(thread);
1506         thread__put(thread);
1507     }
1508 
1509     return 0;
1510 }
1511 
1512 int machine__process_event(struct machine *machine, union perf_event *event,
1513                struct perf_sample *sample)
1514 {
1515     int ret;
1516 
1517     switch (event->header.type) {
1518     case PERF_RECORD_COMM:
1519         ret = machine__process_comm_event(machine, event, sample); break;
1520     case PERF_RECORD_MMAP:
1521         ret = machine__process_mmap_event(machine, event, sample); break;
1522     case PERF_RECORD_MMAP2:
1523         ret = machine__process_mmap2_event(machine, event, sample); break;
1524     case PERF_RECORD_FORK:
1525         ret = machine__process_fork_event(machine, event, sample); break;
1526     case PERF_RECORD_EXIT:
1527         ret = machine__process_exit_event(machine, event, sample); break;
1528     case PERF_RECORD_LOST:
1529         ret = machine__process_lost_event(machine, event, sample); break;
1530     case PERF_RECORD_AUX:
1531         ret = machine__process_aux_event(machine, event); break;
1532     case PERF_RECORD_ITRACE_START:
1533         ret = machine__process_itrace_start_event(machine, event); break;
1534     case PERF_RECORD_LOST_SAMPLES:
1535         ret = machine__process_lost_samples_event(machine, event, sample); break;
1536     case PERF_RECORD_SWITCH:
1537     case PERF_RECORD_SWITCH_CPU_WIDE:
1538         ret = machine__process_switch_event(machine, event); break;
1539     default:
1540         ret = -1;
1541         break;
1542     }
1543 
1544     return ret;
1545 }
1546 
1547 static bool symbol__match_regex(struct symbol *sym, regex_t *regex)
1548 {
1549     if (sym->name && !regexec(regex, sym->name, 0, NULL, 0))
1550         return 1;
1551     return 0;
1552 }
1553 
1554 static void ip__resolve_ams(struct thread *thread,
1555                 struct addr_map_symbol *ams,
1556                 u64 ip)
1557 {
1558     struct addr_location al;
1559 
1560     memset(&al, 0, sizeof(al));
1561     /*
1562      * We cannot use the header.misc hint to determine whether a
1563      * branch stack address is user, kernel, guest, hypervisor.
1564      * Branches may straddle the kernel/user/hypervisor boundaries.
1565      * Thus, we have to try consecutively until we find a match
1566      * or else, the symbol is unknown
1567      */
1568     thread__find_cpumode_addr_location(thread, MAP__FUNCTION, ip, &al);
1569 
1570     ams->addr = ip;
1571     ams->al_addr = al.addr;
1572     ams->sym = al.sym;
1573     ams->map = al.map;
1574 }
1575 
1576 static void ip__resolve_data(struct thread *thread,
1577                  u8 m, struct addr_map_symbol *ams, u64 addr)
1578 {
1579     struct addr_location al;
1580 
1581     memset(&al, 0, sizeof(al));
1582 
1583     thread__find_addr_location(thread, m, MAP__VARIABLE, addr, &al);
1584     if (al.map == NULL) {
1585         /*
1586          * some shared data regions have execute bit set which puts
1587          * their mapping in the MAP__FUNCTION type array.
1588          * Check there as a fallback option before dropping the sample.
1589          */
1590         thread__find_addr_location(thread, m, MAP__FUNCTION, addr, &al);
1591     }
1592 
1593     ams->addr = addr;
1594     ams->al_addr = al.addr;
1595     ams->sym = al.sym;
1596     ams->map = al.map;
1597 }
1598 
1599 struct mem_info *sample__resolve_mem(struct perf_sample *sample,
1600                      struct addr_location *al)
1601 {
1602     struct mem_info *mi = zalloc(sizeof(*mi));
1603 
1604     if (!mi)
1605         return NULL;
1606 
1607     ip__resolve_ams(al->thread, &mi->iaddr, sample->ip);
1608     ip__resolve_data(al->thread, al->cpumode, &mi->daddr, sample->addr);
1609     mi->data_src.val = sample->data_src;
1610 
1611     return mi;
1612 }
1613 
1614 static int add_callchain_ip(struct thread *thread,
1615                 struct callchain_cursor *cursor,
1616                 struct symbol **parent,
1617                 struct addr_location *root_al,
1618                 u8 *cpumode,
1619                 u64 ip,
1620                 bool branch,
1621                 struct branch_flags *flags,
1622                 int nr_loop_iter,
1623                 int samples)
1624 {
1625     struct addr_location al;
1626 
1627     al.filtered = 0;
1628     al.sym = NULL;
1629     if (!cpumode) {
1630         thread__find_cpumode_addr_location(thread, MAP__FUNCTION,
1631                            ip, &al);
1632     } else {
1633         if (ip >= PERF_CONTEXT_MAX) {
1634             switch (ip) {
1635             case PERF_CONTEXT_HV:
1636                 *cpumode = PERF_RECORD_MISC_HYPERVISOR;
1637                 break;
1638             case PERF_CONTEXT_KERNEL:
1639                 *cpumode = PERF_RECORD_MISC_KERNEL;
1640                 break;
1641             case PERF_CONTEXT_USER:
1642                 *cpumode = PERF_RECORD_MISC_USER;
1643                 break;
1644             default:
1645                 pr_debug("invalid callchain context: "
1646                      "%"PRId64"\n", (s64) ip);
1647                 /*
1648                  * It seems the callchain is corrupted.
1649                  * Discard all.
1650                  */
1651                 callchain_cursor_reset(cursor);
1652                 return 1;
1653             }
1654             return 0;
1655         }
1656         thread__find_addr_location(thread, *cpumode, MAP__FUNCTION,
1657                        ip, &al);
1658     }
1659 
1660     if (al.sym != NULL) {
1661         if (perf_hpp_list.parent && !*parent &&
1662             symbol__match_regex(al.sym, &parent_regex))
1663             *parent = al.sym;
1664         else if (have_ignore_callees && root_al &&
1665           symbol__match_regex(al.sym, &ignore_callees_regex)) {
1666             /* Treat this symbol as the root,
1667                forgetting its callees. */
1668             *root_al = al;
1669             callchain_cursor_reset(cursor);
1670         }
1671     }
1672 
1673     if (symbol_conf.hide_unresolved && al.sym == NULL)
1674         return 0;
1675     return callchain_cursor_append(cursor, al.addr, al.map, al.sym,
1676                        branch, flags, nr_loop_iter, samples);
1677 }
1678 
1679 struct branch_info *sample__resolve_bstack(struct perf_sample *sample,
1680                        struct addr_location *al)
1681 {
1682     unsigned int i;
1683     const struct branch_stack *bs = sample->branch_stack;
1684     struct branch_info *bi = calloc(bs->nr, sizeof(struct branch_info));
1685 
1686     if (!bi)
1687         return NULL;
1688 
1689     for (i = 0; i < bs->nr; i++) {
1690         ip__resolve_ams(al->thread, &bi[i].to, bs->entries[i].to);
1691         ip__resolve_ams(al->thread, &bi[i].from, bs->entries[i].from);
1692         bi[i].flags = bs->entries[i].flags;
1693     }
1694     return bi;
1695 }
1696 
1697 #define CHASHSZ 127
1698 #define CHASHBITS 7
1699 #define NO_ENTRY 0xff
1700 
1701 #define PERF_MAX_BRANCH_DEPTH 127
1702 
1703 /* Remove loops. */
1704 static int remove_loops(struct branch_entry *l, int nr)
1705 {
1706     int i, j, off;
1707     unsigned char chash[CHASHSZ];
1708 
1709     memset(chash, NO_ENTRY, sizeof(chash));
1710 
1711     BUG_ON(PERF_MAX_BRANCH_DEPTH > 255);
1712 
1713     for (i = 0; i < nr; i++) {
1714         int h = hash_64(l[i].from, CHASHBITS) % CHASHSZ;
1715 
1716         /* no collision handling for now */
1717         if (chash[h] == NO_ENTRY) {
1718             chash[h] = i;
1719         } else if (l[chash[h]].from == l[i].from) {
1720             bool is_loop = true;
1721             /* check if it is a real loop */
1722             off = 0;
1723             for (j = chash[h]; j < i && i + off < nr; j++, off++)
1724                 if (l[j].from != l[i + off].from) {
1725                     is_loop = false;
1726                     break;
1727                 }
1728             if (is_loop) {
1729                 memmove(l + i, l + i + off,
1730                     (nr - (i + off)) * sizeof(*l));
1731                 nr -= off;
1732             }
1733         }
1734     }
1735     return nr;
1736 }
1737 
1738 /*
1739  * Recolve LBR callstack chain sample
1740  * Return:
1741  * 1 on success get LBR callchain information
1742  * 0 no available LBR callchain information, should try fp
1743  * negative error code on other errors.
1744  */
1745 static int resolve_lbr_callchain_sample(struct thread *thread,
1746                     struct callchain_cursor *cursor,
1747                     struct perf_sample *sample,
1748                     struct symbol **parent,
1749                     struct addr_location *root_al,
1750                     int max_stack)
1751 {
1752     struct ip_callchain *chain = sample->callchain;
1753     int chain_nr = min(max_stack, (int)chain->nr), i;
1754     u8 cpumode = PERF_RECORD_MISC_USER;
1755     u64 ip;
1756 
1757     for (i = 0; i < chain_nr; i++) {
1758         if (chain->ips[i] == PERF_CONTEXT_USER)
1759             break;
1760     }
1761 
1762     /* LBR only affects the user callchain */
1763     if (i != chain_nr) {
1764         struct branch_stack *lbr_stack = sample->branch_stack;
1765         int lbr_nr = lbr_stack->nr, j, k;
1766         bool branch;
1767         struct branch_flags *flags;
1768         /*
1769          * LBR callstack can only get user call chain.
1770          * The mix_chain_nr is kernel call chain
1771          * number plus LBR user call chain number.
1772          * i is kernel call chain number,
1773          * 1 is PERF_CONTEXT_USER,
1774          * lbr_nr + 1 is the user call chain number.
1775          * For details, please refer to the comments
1776          * in callchain__printf
1777          */
1778         int mix_chain_nr = i + 1 + lbr_nr + 1;
1779 
1780         for (j = 0; j < mix_chain_nr; j++) {
1781             int err;
1782             branch = false;
1783             flags = NULL;
1784 
1785             if (callchain_param.order == ORDER_CALLEE) {
1786                 if (j < i + 1)
1787                     ip = chain->ips[j];
1788                 else if (j > i + 1) {
1789                     k = j - i - 2;
1790                     ip = lbr_stack->entries[k].from;
1791                     branch = true;
1792                     flags = &lbr_stack->entries[k].flags;
1793                 } else {
1794                     ip = lbr_stack->entries[0].to;
1795                     branch = true;
1796                     flags = &lbr_stack->entries[0].flags;
1797                 }
1798             } else {
1799                 if (j < lbr_nr) {
1800                     k = lbr_nr - j - 1;
1801                     ip = lbr_stack->entries[k].from;
1802                     branch = true;
1803                     flags = &lbr_stack->entries[k].flags;
1804                 }
1805                 else if (j > lbr_nr)
1806                     ip = chain->ips[i + 1 - (j - lbr_nr)];
1807                 else {
1808                     ip = lbr_stack->entries[0].to;
1809                     branch = true;
1810                     flags = &lbr_stack->entries[0].flags;
1811                 }
1812             }
1813 
1814             err = add_callchain_ip(thread, cursor, parent,
1815                            root_al, &cpumode, ip,
1816                            branch, flags, 0, 0);
1817             if (err)
1818                 return (err < 0) ? err : 0;
1819         }
1820         return 1;
1821     }
1822 
1823     return 0;
1824 }
1825 
1826 static int thread__resolve_callchain_sample(struct thread *thread,
1827                         struct callchain_cursor *cursor,
1828                         struct perf_evsel *evsel,
1829                         struct perf_sample *sample,
1830                         struct symbol **parent,
1831                         struct addr_location *root_al,
1832                         int max_stack)
1833 {
1834     struct branch_stack *branch = sample->branch_stack;
1835     struct ip_callchain *chain = sample->callchain;
1836     int chain_nr = chain->nr;
1837     u8 cpumode = PERF_RECORD_MISC_USER;
1838     int i, j, err, nr_entries;
1839     int skip_idx = -1;
1840     int first_call = 0;
1841     int nr_loop_iter;
1842 
1843     if (perf_evsel__has_branch_callstack(evsel)) {
1844         err = resolve_lbr_callchain_sample(thread, cursor, sample, parent,
1845                            root_al, max_stack);
1846         if (err)
1847             return (err < 0) ? err : 0;
1848     }
1849 
1850     /*
1851      * Based on DWARF debug information, some architectures skip
1852      * a callchain entry saved by the kernel.
1853      */
1854     skip_idx = arch_skip_callchain_idx(thread, chain);
1855 
1856     /*
1857      * Add branches to call stack for easier browsing. This gives
1858      * more context for a sample than just the callers.
1859      *
1860      * This uses individual histograms of paths compared to the
1861      * aggregated histograms the normal LBR mode uses.
1862      *
1863      * Limitations for now:
1864      * - No extra filters
1865      * - No annotations (should annotate somehow)
1866      */
1867 
1868     if (branch && callchain_param.branch_callstack) {
1869         int nr = min(max_stack, (int)branch->nr);
1870         struct branch_entry be[nr];
1871 
1872         if (branch->nr > PERF_MAX_BRANCH_DEPTH) {
1873             pr_warning("corrupted branch chain. skipping...\n");
1874             goto check_calls;
1875         }
1876 
1877         for (i = 0; i < nr; i++) {
1878             if (callchain_param.order == ORDER_CALLEE) {
1879                 be[i] = branch->entries[i];
1880                 /*
1881                  * Check for overlap into the callchain.
1882                  * The return address is one off compared to
1883                  * the branch entry. To adjust for this
1884                  * assume the calling instruction is not longer
1885                  * than 8 bytes.
1886                  */
1887                 if (i == skip_idx ||
1888                     chain->ips[first_call] >= PERF_CONTEXT_MAX)
1889                     first_call++;
1890                 else if (be[i].from < chain->ips[first_call] &&
1891                     be[i].from >= chain->ips[first_call] - 8)
1892                     first_call++;
1893             } else
1894                 be[i] = branch->entries[branch->nr - i - 1];
1895         }
1896 
1897         nr_loop_iter = nr;
1898         nr = remove_loops(be, nr);
1899 
1900         /*
1901          * Get the number of iterations.
1902          * It's only approximation, but good enough in practice.
1903          */
1904         if (nr_loop_iter > nr)
1905             nr_loop_iter = nr_loop_iter - nr + 1;
1906         else
1907             nr_loop_iter = 0;
1908 
1909         for (i = 0; i < nr; i++) {
1910             if (i == nr - 1)
1911                 err = add_callchain_ip(thread, cursor, parent,
1912                                root_al,
1913                                NULL, be[i].to,
1914                                true, &be[i].flags,
1915                                nr_loop_iter, 1);
1916             else
1917                 err = add_callchain_ip(thread, cursor, parent,
1918                                root_al,
1919                                NULL, be[i].to,
1920                                true, &be[i].flags,
1921                                0, 0);
1922 
1923             if (!err)
1924                 err = add_callchain_ip(thread, cursor, parent, root_al,
1925                                NULL, be[i].from,
1926                                true, &be[i].flags,
1927                                0, 0);
1928             if (err == -EINVAL)
1929                 break;
1930             if (err)
1931                 return err;
1932         }
1933         chain_nr -= nr;
1934     }
1935 
1936 check_calls:
1937     for (i = first_call, nr_entries = 0;
1938          i < chain_nr && nr_entries < max_stack; i++) {
1939         u64 ip;
1940 
1941         if (callchain_param.order == ORDER_CALLEE)
1942             j = i;
1943         else
1944             j = chain->nr - i - 1;
1945 
1946 #ifdef HAVE_SKIP_CALLCHAIN_IDX
1947         if (j == skip_idx)
1948             continue;
1949 #endif
1950         ip = chain->ips[j];
1951 
1952         if (ip < PERF_CONTEXT_MAX)
1953                        ++nr_entries;
1954 
1955         err = add_callchain_ip(thread, cursor, parent,
1956                        root_al, &cpumode, ip,
1957                        false, NULL, 0, 0);
1958 
1959         if (err)
1960             return (err < 0) ? err : 0;
1961     }
1962 
1963     return 0;
1964 }
1965 
1966 static int unwind_entry(struct unwind_entry *entry, void *arg)
1967 {
1968     struct callchain_cursor *cursor = arg;
1969 
1970     if (symbol_conf.hide_unresolved && entry->sym == NULL)
1971         return 0;
1972     return callchain_cursor_append(cursor, entry->ip,
1973                        entry->map, entry->sym,
1974                        false, NULL, 0, 0);
1975 }
1976 
1977 static int thread__resolve_callchain_unwind(struct thread *thread,
1978                         struct callchain_cursor *cursor,
1979                         struct perf_evsel *evsel,
1980                         struct perf_sample *sample,
1981                         int max_stack)
1982 {
1983     /* Can we do dwarf post unwind? */
1984     if (!((evsel->attr.sample_type & PERF_SAMPLE_REGS_USER) &&
1985           (evsel->attr.sample_type & PERF_SAMPLE_STACK_USER)))
1986         return 0;
1987 
1988     /* Bail out if nothing was captured. */
1989     if ((!sample->user_regs.regs) ||
1990         (!sample->user_stack.size))
1991         return 0;
1992 
1993     return unwind__get_entries(unwind_entry, cursor,
1994                    thread, sample, max_stack);
1995 }
1996 
1997 int thread__resolve_callchain(struct thread *thread,
1998                   struct callchain_cursor *cursor,
1999                   struct perf_evsel *evsel,
2000                   struct perf_sample *sample,
2001                   struct symbol **parent,
2002                   struct addr_location *root_al,
2003                   int max_stack)
2004 {
2005     int ret = 0;
2006 
2007     callchain_cursor_reset(&callchain_cursor);
2008 
2009     if (callchain_param.order == ORDER_CALLEE) {
2010         ret = thread__resolve_callchain_sample(thread, cursor,
2011                                evsel, sample,
2012                                parent, root_al,
2013                                max_stack);
2014         if (ret)
2015             return ret;
2016         ret = thread__resolve_callchain_unwind(thread, cursor,
2017                                evsel, sample,
2018                                max_stack);
2019     } else {
2020         ret = thread__resolve_callchain_unwind(thread, cursor,
2021                                evsel, sample,
2022                                max_stack);
2023         if (ret)
2024             return ret;
2025         ret = thread__resolve_callchain_sample(thread, cursor,
2026                                evsel, sample,
2027                                parent, root_al,
2028                                max_stack);
2029     }
2030 
2031     return ret;
2032 }
2033 
2034 int machine__for_each_thread(struct machine *machine,
2035                  int (*fn)(struct thread *thread, void *p),
2036                  void *priv)
2037 {
2038     struct rb_node *nd;
2039     struct thread *thread;
2040     int rc = 0;
2041 
2042     for (nd = rb_first(&machine->threads); nd; nd = rb_next(nd)) {
2043         thread = rb_entry(nd, struct thread, rb_node);
2044         rc = fn(thread, priv);
2045         if (rc != 0)
2046             return rc;
2047     }
2048 
2049     list_for_each_entry(thread, &machine->dead_threads, node) {
2050         rc = fn(thread, priv);
2051         if (rc != 0)
2052             return rc;
2053     }
2054     return rc;
2055 }
2056 
2057 int machines__for_each_thread(struct machines *machines,
2058                   int (*fn)(struct thread *thread, void *p),
2059                   void *priv)
2060 {
2061     struct rb_node *nd;
2062     int rc = 0;
2063 
2064     rc = machine__for_each_thread(&machines->host, fn, priv);
2065     if (rc != 0)
2066         return rc;
2067 
2068     for (nd = rb_first(&machines->guests); nd; nd = rb_next(nd)) {
2069         struct machine *machine = rb_entry(nd, struct machine, rb_node);
2070 
2071         rc = machine__for_each_thread(machine, fn, priv);
2072         if (rc != 0)
2073             return rc;
2074     }
2075     return rc;
2076 }
2077 
2078 int __machine__synthesize_threads(struct machine *machine, struct perf_tool *tool,
2079                   struct target *target, struct thread_map *threads,
2080                   perf_event__handler_t process, bool data_mmap,
2081                   unsigned int proc_map_timeout)
2082 {
2083     if (target__has_task(target))
2084         return perf_event__synthesize_thread_map(tool, threads, process, machine, data_mmap, proc_map_timeout);
2085     else if (target__has_cpu(target))
2086         return perf_event__synthesize_threads(tool, process, machine, data_mmap, proc_map_timeout);
2087     /* command specified */
2088     return 0;
2089 }
2090 
2091 pid_t machine__get_current_tid(struct machine *machine, int cpu)
2092 {
2093     if (cpu < 0 || cpu >= MAX_NR_CPUS || !machine->current_tid)
2094         return -1;
2095 
2096     return machine->current_tid[cpu];
2097 }
2098 
2099 int machine__set_current_tid(struct machine *machine, int cpu, pid_t pid,
2100                  pid_t tid)
2101 {
2102     struct thread *thread;
2103 
2104     if (cpu < 0)
2105         return -EINVAL;
2106 
2107     if (!machine->current_tid) {
2108         int i;
2109 
2110         machine->current_tid = calloc(MAX_NR_CPUS, sizeof(pid_t));
2111         if (!machine->current_tid)
2112             return -ENOMEM;
2113         for (i = 0; i < MAX_NR_CPUS; i++)
2114             machine->current_tid[i] = -1;
2115     }
2116 
2117     if (cpu >= MAX_NR_CPUS) {
2118         pr_err("Requested CPU %d too large. ", cpu);
2119         pr_err("Consider raising MAX_NR_CPUS\n");
2120         return -EINVAL;
2121     }
2122 
2123     machine->current_tid[cpu] = tid;
2124 
2125     thread = machine__findnew_thread(machine, pid, tid);
2126     if (!thread)
2127         return -ENOMEM;
2128 
2129     thread->cpu = cpu;
2130     thread__put(thread);
2131 
2132     return 0;
2133 }
2134 
2135 int machine__get_kernel_start(struct machine *machine)
2136 {
2137     struct map *map = machine__kernel_map(machine);
2138     int err = 0;
2139 
2140     /*
2141      * The only addresses above 2^63 are kernel addresses of a 64-bit
2142      * kernel.  Note that addresses are unsigned so that on a 32-bit system
2143      * all addresses including kernel addresses are less than 2^32.  In
2144      * that case (32-bit system), if the kernel mapping is unknown, all
2145      * addresses will be assumed to be in user space - see
2146      * machine__kernel_ip().
2147      */
2148     machine->kernel_start = 1ULL << 63;
2149     if (map) {
2150         err = map__load(map);
2151         if (map->start)
2152             machine->kernel_start = map->start;
2153     }
2154     return err;
2155 }
2156 
2157 struct dso *machine__findnew_dso(struct machine *machine, const char *filename)
2158 {
2159     return dsos__findnew(&machine->dsos, filename);
2160 }
2161 
2162 char *machine__resolve_kernel_addr(void *vmachine, unsigned long long *addrp, char **modp)
2163 {
2164     struct machine *machine = vmachine;
2165     struct map *map;
2166     struct symbol *sym = map_groups__find_symbol(&machine->kmaps, MAP__FUNCTION, *addrp, &map);
2167 
2168     if (sym == NULL)
2169         return NULL;
2170 
2171     *modp = __map__is_kmodule(map) ? (char *)map->dso->short_name : NULL;
2172     *addrp = map->unmap_ip(map, sym->start);
2173     return sym->name;
2174 }