root/tools/perf/util/db-export.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * db-export.c: Support for exporting data suitable for import to a database
 * Copyright (c) 2014, Intel Corporation.
 */

#include <errno.h>
#include <stdlib.h>

#include "dso.h"
#include "evsel.h"
#include "machine.h"
#include "thread.h"
#include "comm.h"
#include "symbol.h"
#include "map.h"
#include "event.h"
#include "thread-stack.h"
#include "callchain.h"
#include "call-path.h"
#include "db-export.h"
#include <linux/zalloc.h>

int db_export__init(struct db_export *dbe)
{
        memset(dbe, 0, sizeof(struct db_export));
        return 0;
}

void db_export__exit(struct db_export *dbe)
{
        call_return_processor__free(dbe->crp);
        dbe->crp = NULL;
}

int db_export__evsel(struct db_export *dbe, struct evsel *evsel)
{
        if (evsel->db_id)
                return 0;

        evsel->db_id = ++dbe->evsel_last_db_id;

        if (dbe->export_evsel)
                return dbe->export_evsel(dbe, evsel);

        return 0;
}

int db_export__machine(struct db_export *dbe, struct machine *machine)
{
        if (machine->db_id)
                return 0;

        machine->db_id = ++dbe->machine_last_db_id;

        if (dbe->export_machine)
                return dbe->export_machine(dbe, machine);

        return 0;
}

int db_export__thread(struct db_export *dbe, struct thread *thread,
                      struct machine *machine, struct thread *main_thread)
{
        u64 main_thread_db_id = 0;

        if (thread__db_id(thread))
                return 0;

        thread__set_db_id(thread, ++dbe->thread_last_db_id);

        if (main_thread)
                main_thread_db_id = thread__db_id(main_thread);

        if (dbe->export_thread)
                return dbe->export_thread(dbe, thread, main_thread_db_id,
                                          machine);

        return 0;
}

static int __db_export__comm(struct db_export *dbe, struct comm *comm,
                             struct thread *thread)
{
        comm->db_id = ++dbe->comm_last_db_id;

        if (dbe->export_comm)
                return dbe->export_comm(dbe, comm, thread);

        return 0;
}

int db_export__comm(struct db_export *dbe, struct comm *comm,
                    struct thread *thread)
{
        if (comm->db_id)
                return 0;

        return __db_export__comm(dbe, comm, thread);
}

/*
 * Export the "exec" comm. The "exec" comm is the program / application command
 * name at the time it first executes. It is used to group threads for the same
 * program. Note that the main thread pid (or thread group id tgid) cannot be
 * used because it does not change when a new program is exec'ed.
 */
int db_export__exec_comm(struct db_export *dbe, struct comm *comm,
                         struct thread *main_thread)
{
        int err;

        if (comm->db_id)
                return 0;

        err = __db_export__comm(dbe, comm, main_thread);
        if (err)
                return err;

        /*
         * Record the main thread for this comm. Note that the main thread can
         * have many "exec" comms because there will be a new one every time it
         * exec's. An "exec" comm however will only ever have 1 main thread.
         * That is different to any other threads for that same program because
         * exec() will effectively kill them, so the relationship between the
         * "exec" comm and non-main threads is 1-to-1. That is why
         * db_export__comm_thread() is called here for the main thread, but it
         * is called for non-main threads when they are exported.
         */
        return db_export__comm_thread(dbe, comm, main_thread);
}

int db_export__comm_thread(struct db_export *dbe, struct comm *comm,
                           struct thread *thread)
{
        u64 db_id;

        db_id = ++dbe->comm_thread_last_db_id;

        if (dbe->export_comm_thread)
                return dbe->export_comm_thread(dbe, db_id, comm, thread);

        return 0;
}

int db_export__dso(struct db_export *dbe, struct dso *dso,
                   struct machine *machine)
{
        if (dso__db_id(dso))
                return 0;

        dso__set_db_id(dso, ++dbe->dso_last_db_id);

        if (dbe->export_dso)
                return dbe->export_dso(dbe, dso, machine);

        return 0;
}

int db_export__symbol(struct db_export *dbe, struct symbol *sym,
                      struct dso *dso)
{
        u64 *sym_db_id = symbol__priv(sym);

        if (*sym_db_id)
                return 0;

        *sym_db_id = ++dbe->symbol_last_db_id;

        if (dbe->export_symbol)
                return dbe->export_symbol(dbe, sym, dso);

        return 0;
}

static int db_ids_from_al(struct db_export *dbe, struct addr_location *al,
                          u64 *dso_db_id, u64 *sym_db_id, u64 *offset)
{
        int err;

        if (al->map) {
                struct dso *dso = map__dso(al->map);

                err = db_export__dso(dbe, dso, maps__machine(thread__maps(al->thread)));
                if (err)
                        return err;
                *dso_db_id = dso__db_id(dso);

                if (!al->sym) {
                        al->sym = symbol__new(al->addr, 0, 0, 0, "unknown");
                        if (al->sym)
                                dso__insert_symbol(dso, al->sym);
                }

                if (al->sym) {
                        u64 *db_id = symbol__priv(al->sym);

                        err = db_export__symbol(dbe, al->sym, dso);
                        if (err)
                                return err;
                        *sym_db_id = *db_id;
                        *offset = al->addr - al->sym->start;
                }
        }

        return 0;
}

static struct call_path *call_path_from_sample(struct db_export *dbe,
                                               struct machine *machine,
                                               struct thread *thread,
                                               struct perf_sample *sample,
                                               struct evsel *evsel)
{
        u64 kernel_start = machine__kernel_start(machine);
        struct call_path *current = &dbe->cpr->call_path;
        enum chain_order saved_order = callchain_param.order;
        struct callchain_cursor *cursor;
        int err;

        if (!symbol_conf.use_callchain || !sample->callchain)
                return NULL;

        /*
         * Since the call path tree must be built starting with the root, we
         * must use ORDER_CALL for call chain resolution, in order to process
         * the callchain starting with the root node and ending with the leaf.
         */
        callchain_param.order = ORDER_CALLER;
        cursor = get_tls_callchain_cursor();
        err = thread__resolve_callchain(thread, cursor, evsel,
                                        sample, NULL, NULL, PERF_MAX_STACK_DEPTH);
        if (err) {
                callchain_param.order = saved_order;
                return NULL;
        }
        callchain_cursor_commit(cursor);

        while (1) {
                struct callchain_cursor_node *node;
                struct addr_location al;
                u64 dso_db_id = 0, sym_db_id = 0, offset = 0;


                node = callchain_cursor_current(cursor);
                if (!node)
                        break;

                /*
                 * Handle export of symbol and dso for this node by
                 * constructing an addr_location struct and then passing it to
                 * db_ids_from_al() to perform the export.
                 */
                addr_location__init(&al);
                al.sym = node->ms.sym;
                al.map = map__get(node->ms.map);
                al.addr = node->ip;
                al.thread = thread__get(thread);

                if (al.map && !al.sym)
                        al.sym = dso__find_symbol(map__dso(al.map), al.addr);

                db_ids_from_al(dbe, &al, &dso_db_id, &sym_db_id, &offset);

                /* add node to the call path tree if it doesn't exist */
                current = call_path__findnew(dbe->cpr, current,
                                             al.sym, node->ip,
                                             kernel_start);

                callchain_cursor_advance(cursor);
                addr_location__exit(&al);
        }

        /* Reset the callchain order to its prior value. */
        callchain_param.order = saved_order;

        if (current == &dbe->cpr->call_path) {
                /* Bail because the callchain was empty. */
                return NULL;
        }

        return current;
}

int db_export__branch_type(struct db_export *dbe, u32 branch_type,
                           const char *name)
{
        if (dbe->export_branch_type)
                return dbe->export_branch_type(dbe, branch_type, name);

        return 0;
}

static int db_export__threads(struct db_export *dbe, struct thread *thread,
                              struct thread *main_thread,
                              struct machine *machine, struct comm **comm_ptr)
{
        struct comm *comm = NULL;
        struct comm *curr_comm;
        int err;

        if (main_thread) {
                /*
                 * A thread has a reference to the main thread, so export the
                 * main thread first.
                 */
                err = db_export__thread(dbe, main_thread, machine, main_thread);
                if (err)
                        return err;
                /*
                 * Export comm before exporting the non-main thread because
                 * db_export__comm_thread() can be called further below.
                 */
                comm = machine__thread_exec_comm(machine, main_thread);
                if (comm) {
                        err = db_export__exec_comm(dbe, comm, main_thread);
                        if (err)
                                return err;
                        *comm_ptr = comm;
                }
        }

        if (thread != main_thread) {
                /*
                 * For a non-main thread, db_export__comm_thread() must be
                 * called only if thread has not previously been exported.
                 */
                bool export_comm_thread = comm && !thread__db_id(thread);

                err = db_export__thread(dbe, thread, machine, main_thread);
                if (err)
                        return err;

                if (export_comm_thread) {
                        err = db_export__comm_thread(dbe, comm, thread);
                        if (err)
                                return err;
                }
        }

        curr_comm = thread__comm(thread);
        if (curr_comm)
                return db_export__comm(dbe, curr_comm, thread);

        return 0;
}

int db_export__sample(struct db_export *dbe, union perf_event *event,
                      struct perf_sample *sample, struct evsel *evsel,
                      struct addr_location *al, struct addr_location *addr_al)
{
        struct thread *thread = al->thread;
        struct export_sample es = {
                .event = event,
                .sample = sample,
                .evsel = evsel,
                .al = al,
        };
        struct thread *main_thread;
        struct comm *comm = NULL;
        struct machine *machine = NULL;
        int err;

        if (thread__maps(thread))
                machine = maps__machine(thread__maps(thread));
        if (!machine)
                return -1;

        err = db_export__evsel(dbe, evsel);
        if (err)
                return err;

        err = db_export__machine(dbe, machine);
        if (err)
                return err;

        main_thread = thread__main_thread(machine, thread);

        err = db_export__threads(dbe, thread, main_thread, machine, &comm);
        if (err)
                goto out_put;

        if (comm)
                es.comm_db_id = comm->db_id;

        es.db_id = ++dbe->sample_last_db_id;

        err = db_ids_from_al(dbe, al, &es.dso_db_id, &es.sym_db_id, &es.offset);
        if (err)
                goto out_put;

        if (dbe->cpr) {
                struct call_path *cp = call_path_from_sample(dbe, machine,
                                                             thread, sample,
                                                             evsel);
                if (cp) {
                        db_export__call_path(dbe, cp);
                        es.call_path_id = cp->db_id;
                }
        }

        if (addr_al) {
                err = db_ids_from_al(dbe, addr_al, &es.addr_dso_db_id,
                                     &es.addr_sym_db_id, &es.addr_offset);
                if (err)
                        goto out_put;
                if (dbe->crp) {
                        err = thread_stack__process(thread, comm, sample, al,
                                                    addr_al, es.db_id,
                                                    dbe->crp);
                        if (err)
                                goto out_put;
                }
        }

        if (dbe->export_sample)
                err = dbe->export_sample(dbe, &es);

out_put:
        thread__put(main_thread);
        return err;
}

static struct {
        u32 branch_type;
        const char *name;
} branch_types[] = {
        {0, "no branch"},
        {PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CALL, "call"},
        {PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_RETURN, "return"},
        {PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CONDITIONAL, "conditional jump"},
        {PERF_IP_FLAG_BRANCH, "unconditional jump"},
        {PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CALL | PERF_IP_FLAG_INTERRUPT,
         "software interrupt"},
        {PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_RETURN | PERF_IP_FLAG_INTERRUPT,
         "return from interrupt"},
        {PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CALL | PERF_IP_FLAG_SYSCALLRET,
         "system call"},
        {PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_RETURN | PERF_IP_FLAG_SYSCALLRET,
         "return from system call"},
        {PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_ASYNC, "asynchronous branch"},
        {PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CALL | PERF_IP_FLAG_ASYNC |
         PERF_IP_FLAG_INTERRUPT, "hardware interrupt"},
        {PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_TX_ABORT, "transaction abort"},
        {PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_TRACE_BEGIN, "trace begin"},
        {PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_TRACE_END, "trace end"},
        {PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CALL | PERF_IP_FLAG_VMENTRY, "vm entry"},
        {PERF_IP_FLAG_BRANCH | PERF_IP_FLAG_CALL | PERF_IP_FLAG_VMEXIT, "vm exit"},
        {0, NULL}
};

int db_export__branch_types(struct db_export *dbe)
{
        int i, err = 0;

        for (i = 0; branch_types[i].name ; i++) {
                err = db_export__branch_type(dbe, branch_types[i].branch_type,
                                             branch_types[i].name);
                if (err)
                        break;
        }

        /* Add trace begin / end variants */
        for (i = 0; branch_types[i].name ; i++) {
                const char *name = branch_types[i].name;
                u32 type = branch_types[i].branch_type;
                char buf[64];

                if (type == PERF_IP_FLAG_BRANCH ||
                    (type & (PERF_IP_FLAG_TRACE_BEGIN | PERF_IP_FLAG_TRACE_END)))
                        continue;

                snprintf(buf, sizeof(buf), "trace begin / %s", name);
                err = db_export__branch_type(dbe, type | PERF_IP_FLAG_TRACE_BEGIN, buf);
                if (err)
                        break;

                snprintf(buf, sizeof(buf), "%s / trace end", name);
                err = db_export__branch_type(dbe, type | PERF_IP_FLAG_TRACE_END, buf);
                if (err)
                        break;
        }

        return err;
}

int db_export__call_path(struct db_export *dbe, struct call_path *cp)
{
        int err;

        if (cp->db_id)
                return 0;

        if (cp->parent) {
                err = db_export__call_path(dbe, cp->parent);
                if (err)
                        return err;
        }

        cp->db_id = ++dbe->call_path_last_db_id;

        if (dbe->export_call_path)
                return dbe->export_call_path(dbe, cp);

        return 0;
}

int db_export__call_return(struct db_export *dbe, struct call_return *cr,
                           u64 *parent_db_id)
{
        int err;

        err = db_export__call_path(dbe, cr->cp);
        if (err)
                return err;

        if (!cr->db_id)
                cr->db_id = ++dbe->call_return_last_db_id;

        if (parent_db_id) {
                if (!*parent_db_id)
                        *parent_db_id = ++dbe->call_return_last_db_id;
                cr->parent_db_id = *parent_db_id;
        }

        if (dbe->export_call_return)
                return dbe->export_call_return(dbe, cr);

        return 0;
}

static int db_export__pid_tid(struct db_export *dbe, struct machine *machine,
                              pid_t pid, pid_t tid, u64 *db_id,
                              struct comm **comm_ptr, bool *is_idle)
{
        struct thread *thread = machine__find_thread(machine, pid, tid);
        struct thread *main_thread;
        int err = 0;

        if (!thread || !thread__comm_set(thread))
                goto out_put;

        *is_idle = !thread__pid(thread) && !thread__tid(thread);

        main_thread = thread__main_thread(machine, thread);

        err = db_export__threads(dbe, thread, main_thread, machine, comm_ptr);

        *db_id = thread__db_id(thread);

        thread__put(main_thread);
out_put:
        thread__put(thread);

        return err;
}

int db_export__switch(struct db_export *dbe, union perf_event *event,
                      struct perf_sample *sample, struct machine *machine)
{
        bool out = event->header.misc & PERF_RECORD_MISC_SWITCH_OUT;
        bool out_preempt = out &&
                (event->header.misc & PERF_RECORD_MISC_SWITCH_OUT_PREEMPT);
        int flags = out | (out_preempt << 1);
        bool is_idle_a = false, is_idle_b = false;
        u64 th_a_id = 0, th_b_id = 0;
        u64 comm_out_id, comm_in_id;
        struct comm *comm_a = NULL;
        struct comm *comm_b = NULL;
        u64 th_out_id, th_in_id;
        u64 db_id;
        int err;

        err = db_export__machine(dbe, machine);
        if (err)
                return err;

        err = db_export__pid_tid(dbe, machine, sample->pid, sample->tid,
                                 &th_a_id, &comm_a, &is_idle_a);
        if (err)
                return err;

        if (event->header.type == PERF_RECORD_SWITCH_CPU_WIDE) {
                pid_t pid = event->context_switch.next_prev_pid;
                pid_t tid = event->context_switch.next_prev_tid;

                err = db_export__pid_tid(dbe, machine, pid, tid, &th_b_id,
                                         &comm_b, &is_idle_b);
                if (err)
                        return err;
        }

        /*
         * Do not export if both threads are unknown (i.e. not being traced),
         * or one is unknown and the other is the idle task.
         */
        if ((!th_a_id || is_idle_a) && (!th_b_id || is_idle_b))
                return 0;

        db_id = ++dbe->context_switch_last_db_id;

        if (out) {
                th_out_id   = th_a_id;
                th_in_id    = th_b_id;
                comm_out_id = comm_a ? comm_a->db_id : 0;
                comm_in_id  = comm_b ? comm_b->db_id : 0;
        } else {
                th_out_id   = th_b_id;
                th_in_id    = th_a_id;
                comm_out_id = comm_b ? comm_b->db_id : 0;
                comm_in_id  = comm_a ? comm_a->db_id : 0;
        }

        if (dbe->export_context_switch)
                return dbe->export_context_switch(dbe, db_id, machine, sample,
                                                  th_out_id, comm_out_id,
                                                  th_in_id, comm_in_id, flags);
        return 0;
}