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[mirror_ubuntu-hirsute-kernel.git] / tools / perf / builtin-lock.c

#include "builtin.h"
#include "perf.h"

#include "util/util.h"
#include "util/cache.h"
#include "util/symbol.h"
#include "util/thread.h"
#include "util/header.h"

#include "util/parse-options.h"
#include "util/trace-event.h"

#include "util/debug.h"
#include "util/session.h"

#include <sys/types.h>
#include <sys/prctl.h>
#include <semaphore.h>
#include <pthread.h>
#include <math.h>
#include <limits.h>

#include <linux/list.h>
#include <linux/hash.h>

/* based on kernel/lockdep.c */
#define LOCKHASH_BITS           12
#define LOCKHASH_SIZE           (1UL << LOCKHASH_BITS)

static struct list_head lockhash_table[LOCKHASH_SIZE];

#define __lockhashfn(key)       hash_long((unsigned long)key, LOCKHASH_BITS)
#define lockhashentry(key)      (lockhash_table + __lockhashfn((key)))

#define LOCK_STATE_UNLOCKED     0              /* initial state */
#define LOCK_STATE_LOCKED       1

struct lock_stat {
        struct list_head        hash_entry;
        struct rb_node          rb;             /* used for sorting */

        /*
         * FIXME: raw_field_value() returns unsigned long long,
         * so address of lockdep_map should be dealed as 64bit.
         * Is there more better solution?
         */
        void                    *addr;          /* address of lockdep_map, used as ID */
        char                    *name;          /* for strcpy(), we cannot use const */

        int                     state;
        u64                     prev_event_time; /* timestamp of previous event */

        unsigned int            nr_acquired;
        unsigned int            nr_acquire;
        unsigned int            nr_contended;
        unsigned int            nr_release;

        /* these times are in nano sec. */
        u64                     wait_time_total;
        u64                     wait_time_min;
        u64                     wait_time_max;
};

/* build simple key function one is bigger than two */
#define SINGLE_KEY(member)                                              \
        static int lock_stat_key_ ## member(struct lock_stat *one,      \
                                         struct lock_stat *two)         \
        {                                                               \
                return one->member > two->member;                       \
        }

SINGLE_KEY(nr_acquired)
SINGLE_KEY(nr_contended)
SINGLE_KEY(wait_time_total)
SINGLE_KEY(wait_time_min)
SINGLE_KEY(wait_time_max)

struct lock_key {
        /*
         * name: the value for specify by user
         * this should be simpler than raw name of member
         * e.g. nr_acquired -> acquired, wait_time_total -> wait_total
         */
        const char              *name;
        int                     (*key)(struct lock_stat*, struct lock_stat*);
};

static const char               *sort_key = "acquired";

static int                      (*compare)(struct lock_stat *, struct lock_stat *);

static struct rb_root           result; /* place to store sorted data */

#define DEF_KEY_LOCK(name, fn_suffix)   \
        { #name, lock_stat_key_ ## fn_suffix }
struct lock_key keys[] = {
        DEF_KEY_LOCK(acquired, nr_acquired),
        DEF_KEY_LOCK(contended, nr_contended),
        DEF_KEY_LOCK(wait_total, wait_time_total),
        DEF_KEY_LOCK(wait_min, wait_time_min),
        DEF_KEY_LOCK(wait_max, wait_time_max),

        /* extra comparisons much complicated should be here */

        { NULL, NULL }
};

static void select_key(void)
{
        int i;

        for (i = 0; keys[i].name; i++) {
                if (!strcmp(keys[i].name, sort_key)) {
                        compare = keys[i].key;
                        return;
                }
        }

        die("Unknown compare key:%s\n", sort_key);
}

static void insert_to_result(struct lock_stat *st,
                             int (*bigger)(struct lock_stat *, struct lock_stat *))
{
        struct rb_node **rb = &result.rb_node;
        struct rb_node *parent = NULL;
        struct lock_stat *p;

        while (*rb) {
                p = container_of(*rb, struct lock_stat, rb);
                parent = *rb;

                if (bigger(st, p))
                        rb = &(*rb)->rb_left;
                else
                        rb = &(*rb)->rb_right;
        }

        rb_link_node(&st->rb, parent, rb);
        rb_insert_color(&st->rb, &result);
}

/* returns left most element of result, and erase it */
static struct lock_stat *pop_from_result(void)
{
        struct rb_node *node = result.rb_node;

        if (!node)
                return NULL;

        while (node->rb_left)
                node = node->rb_left;

        rb_erase(node, &result);
        return container_of(node, struct lock_stat, rb);
}

static struct lock_stat *lock_stat_findnew(void *addr, const char *name)
{
        struct list_head *entry = lockhashentry(addr);
        struct lock_stat *ret, *new;

        list_for_each_entry(ret, entry, hash_entry) {
                if (ret->addr == addr)
                        return ret;
        }

        new = zalloc(sizeof(struct lock_stat));
        if (!new)
                goto alloc_failed;

        new->addr = addr;
        new->name = zalloc(sizeof(char) * strlen(name) + 1);
        if (!new->name)
                goto alloc_failed;
        strcpy(new->name, name);

        /* LOCK_STATE_UNLOCKED == 0 isn't guaranteed forever */
        new->state = LOCK_STATE_UNLOCKED;
        new->wait_time_min = ULLONG_MAX;

        list_add(&new->hash_entry, entry);
        return new;

alloc_failed:
        die("memory allocation failed\n");
}

static char                     const *input_name = "perf.data";

static int                      profile_cpu = -1;

struct raw_event_sample {
        u32                     size;
        char                    data[0];
};

struct trace_acquire_event {
        void                    *addr;
        const char              *name;
};

struct trace_acquired_event {
        void                    *addr;
        const char              *name;
};

struct trace_contended_event {
        void                    *addr;
        const char              *name;
};

struct trace_release_event {
        void                    *addr;
        const char              *name;
};

struct trace_lock_handler {
        void (*acquire_event)(struct trace_acquire_event *,
                              struct event *,
                              int cpu,
                              u64 timestamp,
                              struct thread *thread);

        void (*acquired_event)(struct trace_acquired_event *,
                               struct event *,
                               int cpu,
                               u64 timestamp,
                               struct thread *thread);

        void (*contended_event)(struct trace_contended_event *,
                                struct event *,
                                int cpu,
                                u64 timestamp,
                                struct thread *thread);

        void (*release_event)(struct trace_release_event *,
                              struct event *,
                              int cpu,
                              u64 timestamp,
                              struct thread *thread);
};

static void
report_lock_acquire_event(struct trace_acquire_event *acquire_event,
                        struct event *__event __used,
                        int cpu __used,
                        u64 timestamp,
                        struct thread *thread __used)
{
        struct lock_stat *st;

        st = lock_stat_findnew(acquire_event->addr, acquire_event->name);

        switch (st->state) {
        case LOCK_STATE_UNLOCKED:
                break;
        case LOCK_STATE_LOCKED:
                break;
        default:
                BUG_ON(1);
                break;
        }

        st->prev_event_time = timestamp;
}

static void
report_lock_acquired_event(struct trace_acquired_event *acquired_event,
                         struct event *__event __used,
                         int cpu __used,
                         u64 timestamp,
                         struct thread *thread __used)
{
        struct lock_stat *st;

        st = lock_stat_findnew(acquired_event->addr, acquired_event->name);

        switch (st->state) {
        case LOCK_STATE_UNLOCKED:
                st->state = LOCK_STATE_LOCKED;
                st->nr_acquired++;
                break;
        case LOCK_STATE_LOCKED:
                break;
        default:
                BUG_ON(1);
                break;
        }

        st->prev_event_time = timestamp;
}

static void
report_lock_contended_event(struct trace_contended_event *contended_event,
                          struct event *__event __used,
                          int cpu __used,
                          u64 timestamp,
                          struct thread *thread __used)
{
        struct lock_stat *st;

        st = lock_stat_findnew(contended_event->addr, contended_event->name);

        switch (st->state) {
        case LOCK_STATE_UNLOCKED:
                break;
        case LOCK_STATE_LOCKED:
                st->nr_contended++;
                break;
        default:
                BUG_ON(1);
                break;
        }

        st->prev_event_time = timestamp;
}

static void
report_lock_release_event(struct trace_release_event *release_event,
                        struct event *__event __used,
                        int cpu __used,
                        u64 timestamp,
                        struct thread *thread __used)
{
        struct lock_stat *st;
        u64 hold_time;

        st = lock_stat_findnew(release_event->addr, release_event->name);

        switch (st->state) {
        case LOCK_STATE_UNLOCKED:
                break;
        case LOCK_STATE_LOCKED:
                st->state = LOCK_STATE_UNLOCKED;
                hold_time = timestamp - st->prev_event_time;

                if (timestamp < st->prev_event_time) {
                        /* terribly, this can happen... */
                        goto end;
                }

                if (st->wait_time_min > hold_time)
                        st->wait_time_min = hold_time;
                if (st->wait_time_max < hold_time)
                        st->wait_time_max = hold_time;
                st->wait_time_total += hold_time;

                st->nr_release++;
                break;
        default:
                BUG_ON(1);
                break;
        }

end:
        st->prev_event_time = timestamp;
}

/* lock oriented handlers */
/* TODO: handlers for CPU oriented, thread oriented */
static struct trace_lock_handler report_lock_ops  = {
        .acquire_event          = report_lock_acquire_event,
        .acquired_event         = report_lock_acquired_event,
        .contended_event        = report_lock_contended_event,
        .release_event          = report_lock_release_event,
};

static struct trace_lock_handler *trace_handler;

static void
process_lock_acquire_event(void *data,
                           struct event *event __used,
                           int cpu __used,
                           u64 timestamp __used,
                           struct thread *thread __used)
{
        struct trace_acquire_event acquire_event;
        u64 tmp;                /* this is required for casting... */

        tmp = raw_field_value(event, "lockdep_addr", data);
        memcpy(&acquire_event.addr, &tmp, sizeof(void *));
        acquire_event.name = (char *)raw_field_ptr(event, "name", data);

        if (trace_handler->acquire_event)
                trace_handler->acquire_event(&acquire_event, event, cpu, timestamp, thread);
}

static void
process_lock_acquired_event(void *data,
                            struct event *event __used,
                            int cpu __used,
                            u64 timestamp __used,
                            struct thread *thread __used)
{
        struct trace_acquired_event acquired_event;
        u64 tmp;                /* this is required for casting... */

        tmp = raw_field_value(event, "lockdep_addr", data);
        memcpy(&acquired_event.addr, &tmp, sizeof(void *));
        acquired_event.name = (char *)raw_field_ptr(event, "name", data);

        if (trace_handler->acquire_event)
                trace_handler->acquired_event(&acquired_event, event, cpu, timestamp, thread);
}

static void
process_lock_contended_event(void *data,
                             struct event *event __used,
                             int cpu __used,
                             u64 timestamp __used,
                             struct thread *thread __used)
{
        struct trace_contended_event contended_event;
        u64 tmp;                /* this is required for casting... */

        tmp = raw_field_value(event, "lockdep_addr", data);
        memcpy(&contended_event.addr, &tmp, sizeof(void *));
        contended_event.name = (char *)raw_field_ptr(event, "name", data);

        if (trace_handler->acquire_event)
                trace_handler->contended_event(&contended_event, event, cpu, timestamp, thread);
}

static void
process_lock_release_event(void *data,
                           struct event *event __used,
                           int cpu __used,
                           u64 timestamp __used,
                           struct thread *thread __used)
{
        struct trace_release_event release_event;
        u64 tmp;                /* this is required for casting... */

        tmp = raw_field_value(event, "lockdep_addr", data);
        memcpy(&release_event.addr, &tmp, sizeof(void *));
        release_event.name = (char *)raw_field_ptr(event, "name", data);

        if (trace_handler->acquire_event)
                trace_handler->release_event(&release_event, event, cpu, timestamp, thread);
}

static void
process_raw_event(void *data, int cpu,
                  u64 timestamp, struct thread *thread)
{
        struct event *event;
        int type;

        type = trace_parse_common_type(data);
        event = trace_find_event(type);

        if (!strcmp(event->name, "lock_acquire"))
                process_lock_acquire_event(data, event, cpu, timestamp, thread);
        if (!strcmp(event->name, "lock_acquired"))
                process_lock_acquired_event(data, event, cpu, timestamp, thread);
        if (!strcmp(event->name, "lock_contended"))
                process_lock_contended_event(data, event, cpu, timestamp, thread);
        if (!strcmp(event->name, "lock_release"))
                process_lock_release_event(data, event, cpu, timestamp, thread);
}

struct raw_event_queue {
        u64                     timestamp;
        int                     cpu;
        void                    *data;
        struct thread           *thread;
        struct list_head        list;
};

static LIST_HEAD(raw_event_head);

#define FLUSH_PERIOD    (5 * NSEC_PER_SEC)

static u64 flush_limit = ULLONG_MAX;
static u64 last_flush = 0;
struct raw_event_queue *last_inserted;

static void flush_raw_event_queue(u64 limit)
{
        struct raw_event_queue *tmp, *iter;

        list_for_each_entry_safe(iter, tmp, &raw_event_head, list) {
                if (iter->timestamp > limit)
                        return;

                if (iter == last_inserted)
                        last_inserted = NULL;

                process_raw_event(iter->data, iter->cpu, iter->timestamp,
                                  iter->thread);

                last_flush = iter->timestamp;
                list_del(&iter->list);
                free(iter->data);
                free(iter);
        }
}

static void __queue_raw_event_end(struct raw_event_queue *new)
{
        struct raw_event_queue *iter;

        list_for_each_entry_reverse(iter, &raw_event_head, list) {
                if (iter->timestamp < new->timestamp) {
                        list_add(&new->list, &iter->list);
                        return;
                }
        }

        list_add(&new->list, &raw_event_head);
}

static void __queue_raw_event_before(struct raw_event_queue *new,
                                     struct raw_event_queue *iter)
{
        list_for_each_entry_continue_reverse(iter, &raw_event_head, list) {
                if (iter->timestamp < new->timestamp) {
                        list_add(&new->list, &iter->list);
                        return;
                }
        }

        list_add(&new->list, &raw_event_head);
}

static void __queue_raw_event_after(struct raw_event_queue *new,
                                     struct raw_event_queue *iter)
{
        list_for_each_entry_continue(iter, &raw_event_head, list) {
                if (iter->timestamp > new->timestamp) {
                        list_add_tail(&new->list, &iter->list);
                        return;
                }
        }
        list_add_tail(&new->list, &raw_event_head);
}

/* The queue is ordered by time */
static void __queue_raw_event(struct raw_event_queue *new)
{
        if (!last_inserted) {
                __queue_raw_event_end(new);
                return;
        }

        /*
         * Most of the time the current event has a timestamp
         * very close to the last event inserted, unless we just switched
         * to another event buffer. Having a sorting based on a list and
         * on the last inserted event that is close to the current one is
         * probably more efficient than an rbtree based sorting.
         */
        if (last_inserted->timestamp >= new->timestamp)
                __queue_raw_event_before(new, last_inserted);
        else
                __queue_raw_event_after(new, last_inserted);
}

static void queue_raw_event(void *data, int raw_size, int cpu,
                            u64 timestamp, struct thread *thread)
{
        struct raw_event_queue *new;

        if (flush_limit == ULLONG_MAX)
                flush_limit = timestamp + FLUSH_PERIOD;

        if (timestamp < last_flush) {
                printf("Warning: Timestamp below last timeslice flush\n");
                return;
        }

        new = malloc(sizeof(*new));
        if (!new)
                die("Not enough memory\n");

        new->timestamp = timestamp;
        new->cpu = cpu;
        new->thread = thread;

        new->data = malloc(raw_size);
        if (!new->data)
                die("Not enough memory\n");

        memcpy(new->data, data, raw_size);

        __queue_raw_event(new);
        last_inserted = new;

        /*
         * We want to have a slice of events covering 2 * FLUSH_PERIOD
         * If FLUSH_PERIOD is big enough, it ensures every events that occured
         * in the first half of the timeslice have all been buffered and there
         * are none remaining (we need that because of the weakly ordered
         * event recording we have). Then once we reach the 2 * FLUSH_PERIOD
         * timeslice, we flush the first half to be gentle with the memory
         * (the second half can still get new events in the middle, so wait
         * another period to flush it)
         */
        if (new->timestamp > flush_limit &&
                new->timestamp - flush_limit > FLUSH_PERIOD) {
                flush_limit += FLUSH_PERIOD;
                flush_raw_event_queue(flush_limit);
        }
}

static int process_sample_event(event_t *event, struct perf_session *session)
{
        struct thread *thread;
        struct sample_data data;

        bzero(&data, sizeof(struct sample_data));
        event__parse_sample(event, session->sample_type, &data);
        thread = perf_session__findnew(session, data.pid);

        if (thread == NULL) {
                pr_debug("problem processing %d event, skipping it.\n",
                         event->header.type);
                return -1;
        }

        dump_printf(" ... thread: %s:%d\n", thread->comm, thread->pid);

        if (profile_cpu != -1 && profile_cpu != (int) data.cpu)
                return 0;

        queue_raw_event(data.raw_data, data.raw_size, data.cpu, data.time, thread);

        return 0;
}

/* TODO: various way to print, coloring, nano or milli sec */
static void print_result(void)
{
        struct lock_stat *st;
        char cut_name[20];

        printf("%18s ", "ID");
        printf("%20s ", "Name");
        printf("%10s ", "acquired");
        printf("%10s ", "contended");

        printf("%15s ", "total wait (ns)");
        printf("%15s ", "max wait (ns)");
        printf("%15s ", "min wait (ns)");

        printf("\n\n");

        while ((st = pop_from_result())) {
                bzero(cut_name, 20);

                printf("%p ", st->addr);

                if (strlen(st->name) < 16) {
                        /* output raw name */
                        printf("%20s ", st->name);
                } else {
                        strncpy(cut_name, st->name, 16);
                        cut_name[16] = '.';
                        cut_name[17] = '.';
                        cut_name[18] = '.';
                        cut_name[19] = '\0';
                        /* cut off name for saving output style */
                        printf("%20s ", cut_name);
                }

                printf("%10u ", st->nr_acquired);
                printf("%10u ", st->nr_contended);

                printf("%15llu ", st->wait_time_total);
                printf("%15llu ", st->wait_time_max);
                printf("%15llu ", st->wait_time_min == ULLONG_MAX ?
                       0 : st->wait_time_min);
                printf("\n");
        }
}

static void dump_map(void)
{
        unsigned int i;
        struct lock_stat *st;

        for (i = 0; i < LOCKHASH_SIZE; i++) {
                list_for_each_entry(st, &lockhash_table[i], hash_entry) {
                        printf("%p: %s\n", st->addr, st->name);
                }
        }
}

static struct perf_event_ops eops = {
        .sample                 = process_sample_event,
        .comm                   = event__process_comm,
};

static struct perf_session *session;

static int read_events(void)
{
        session = perf_session__new(input_name, O_RDONLY, 0);
        if (!session)
                die("Initializing perf session failed\n");

        return perf_session__process_events(session, &eops);
}

static void sort_result(void)
{
        unsigned int i;
        struct lock_stat *st;

        for (i = 0; i < LOCKHASH_SIZE; i++) {
                list_for_each_entry(st, &lockhash_table[i], hash_entry) {
                        insert_to_result(st, compare);
                }
        }
}

static void __cmd_report(void)
{
        setup_pager();
        select_key();
        read_events();
        flush_raw_event_queue(ULLONG_MAX);
        sort_result();
        print_result();
}

static const char * const report_usage[] = {
        "perf lock report [<options>]",
        NULL
};

static const struct option report_options[] = {
        OPT_STRING('k', "key", &sort_key, "acquired",
                    "key for sorting"),
        /* TODO: type */
        OPT_END()
};

static const char * const lock_usage[] = {
        "perf lock [<options>] {record|trace|report}",
        NULL
};

static const struct option lock_options[] = {
        OPT_STRING('i', "input", &input_name, "file", "input file name"),
        OPT_BOOLEAN('v', "verbose", &verbose, "be more verbose (show symbol address, etc)"),
        OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace, "dump raw trace in ASCII"),
        OPT_END()
};

static const char *record_args[] = {
        "record",
        "-a",
        "-R",
        "-f",
        "-m", "1024",
        "-c", "1",
        "-e", "lock:lock_acquire:r",
        "-e", "lock:lock_acquired:r",
        "-e", "lock:lock_contended:r",
        "-e", "lock:lock_release:r",
};

static int __cmd_record(int argc, const char **argv)
{
        unsigned int rec_argc, i, j;
        const char **rec_argv;

        rec_argc = ARRAY_SIZE(record_args) + argc - 1;
        rec_argv = calloc(rec_argc + 1, sizeof(char *));

        for (i = 0; i < ARRAY_SIZE(record_args); i++)
                rec_argv[i] = strdup(record_args[i]);

        for (j = 1; j < (unsigned int)argc; j++, i++)
                rec_argv[i] = argv[j];

        BUG_ON(i != rec_argc);

        return cmd_record(i, rec_argv, NULL);
}

int cmd_lock(int argc, const char **argv, const char *prefix __used)
{
        unsigned int i;

        symbol__init();
        for (i = 0; i < LOCKHASH_SIZE; i++)
                INIT_LIST_HEAD(lockhash_table + i);

        argc = parse_options(argc, argv, lock_options, lock_usage,
                             PARSE_OPT_STOP_AT_NON_OPTION);
        if (!argc)
                usage_with_options(lock_usage, lock_options);

        if (!strncmp(argv[0], "rec", 3)) {
                return __cmd_record(argc, argv);
        } else if (!strncmp(argv[0], "report", 6)) {
                trace_handler = &report_lock_ops;
                if (argc) {
                        argc = parse_options(argc, argv,
                                             report_options, report_usage, 0);
                        if (argc)
                                usage_with_options(report_usage, report_options);
                }
                __cmd_report();
        } else if (!strcmp(argv[0], "trace")) {
                /* Aliased to 'perf trace' */
                return cmd_trace(argc, argv, prefix);
        } else if (!strcmp(argv[0], "map")) {
                /* recycling report_lock_ops */
                trace_handler = &report_lock_ops;
                setup_pager();
                read_events();
                dump_map();
        } else {
                usage_with_options(lock_usage, lock_options);
        }

        return 0;
}