db-export.c

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/*
 * db-export.c: Support for exporting data suitable for import to a database
 * Copyright (c) 2014, Intel Corporation.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 */

#include <errno.h>

#include "evsel.h"
#include "machine.h"
#include "thread.h"
#include "comm.h"
#include "symbol.h"
#include "event.h"
#include "util.h"
#include "thread-stack.h"
#include "callchain.h"
#include "call-path.h"
#include "db-export.h"

struct deferred_export {
    struct list_head node;
    struct comm *comm;
};

static int db_export__deferred(struct db_export *dbe)
{
    struct deferred_export *de;
    int err;

    while (!list_empty(&dbe->deferred)) {
        de = list_entry(dbe->deferred.next, struct deferred_export,
                node);
        err = dbe->export_comm(dbe, de->comm);
        list_del(&de->node);
        free(de);
        if (err)
            return err;
    }

    return 0;
}

static void db_export__free_deferred(struct db_export *dbe)
{
    struct deferred_export *de;

    while (!list_empty(&dbe->deferred)) {
        de = list_entry(dbe->deferred.next, struct deferred_export,
                node);
        list_del(&de->node);
        free(de);
    }
}

static int db_export__defer_comm(struct db_export *dbe, struct comm *comm)
{
    struct deferred_export *de;

    de = zalloc(sizeof(struct deferred_export));
    if (!de)
        return -ENOMEM;

    de->comm = comm;
    list_add_tail(&de->node, &dbe->deferred);

    return 0;
}

int db_export__init(struct db_export *dbe)
{
    memset(dbe, 0, sizeof(struct db_export));
    INIT_LIST_HEAD(&dbe->deferred);
    return 0;
}

int db_export__flush(struct db_export *dbe)
{
    return db_export__deferred(dbe);
}

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

int db_export__evsel(struct db_export *dbe, struct perf_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 comm *comm)
{
    struct thread *main_thread;
    u64 main_thread_db_id = 0;
    int err;

    if (thread->db_id)
        return 0;

    thread->db_id = ++dbe->thread_last_db_id;

    if (thread->pid_ != -1) {
        if (thread->pid_ == thread->tid) {
            main_thread = thread;
        } else {
            main_thread = machine__findnew_thread(machine,
                                  thread->pid_,
                                  thread->pid_);
            if (!main_thread)
                return -ENOMEM;
            err = db_export__thread(dbe, main_thread, machine,
                        comm);
            if (err)
                goto out_put;
            if (comm) {
                err = db_export__comm_thread(dbe, comm, thread);
                if (err)
                    goto out_put;
            }
        }
        main_thread_db_id = main_thread->db_id;
        if (main_thread != thread)
            thread__put(main_thread);
    }

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

    return 0;

out_put:
    thread__put(main_thread);
    return err;
}

int db_export__comm(struct db_export *dbe, struct comm *comm,
            struct thread *main_thread)
{
    int err;

    if (comm->db_id)
        return 0;

    comm->db_id = ++dbe->comm_last_db_id;

    if (dbe->export_comm) {
        if (main_thread->comm_set)
            err = dbe->export_comm(dbe, comm);
        else
            err = db_export__defer_comm(dbe, comm);
        if (err)
            return err;
    }

    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)
        return 0;

    dso->db_id = ++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 = al->map->dso;

        err = db_export__dso(dbe, dso, al->machine);
        if (err)
            return err;
        *dso_db_id = dso->db_id;

        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 perf_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;
    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;
    err = thread__resolve_callchain(thread, &callchain_cursor, evsel,
                    sample, NULL, NULL, PERF_MAX_STACK_DEPTH);
    if (err) {
        callchain_param.order = saved_order;
        return NULL;
    }
    callchain_cursor_commit(&callchain_cursor);

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

        memset(&al, 0, sizeof(al));

        node = callchain_cursor_current(&callchain_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.
         */
        al.sym = node->sym;
        al.map = node->map;
        al.machine = machine;
        al.addr = node->ip;

        if (al.map && !al.sym)
            al.sym = dso__find_symbol(al.map->dso, 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(&callchain_cursor);
    }

    /* 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;
}

int db_export__sample(struct db_export *dbe, union perf_event *event,
              struct perf_sample *sample, struct perf_evsel *evsel,
              struct addr_location *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;
    int err;

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

    err = db_export__machine(dbe, al->machine);
    if (err)
        return err;

    main_thread = thread__main_thread(al->machine, thread);
    if (main_thread)
        comm = machine__thread_exec_comm(al->machine, main_thread);

    err = db_export__thread(dbe, thread, al->machine, comm);
    if (err)
        goto out_put;

    if (comm) {
        err = db_export__comm(dbe, comm, main_thread);
        if (err)
            goto out_put;
        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, al->machine,
                                 thread, sample,
                                 evsel);
        if (cp) {
            db_export__call_path(dbe, cp);
            es.call_path_id = cp->db_id;
        }
    }

    if ((evsel->attr.sample_type & PERF_SAMPLE_ADDR) &&
        sample_addr_correlates_sym(&evsel->attr)) {
        struct addr_location addr_al;

        thread__resolve(thread, &addr_al, sample);
        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"},
    {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;
    }
    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)
{
    int err;

    if (cr->db_id)
        return 0;

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

    cr->db_id = ++dbe->call_return_last_db_id;

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

    return 0;
}