/*

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 *   - Redistributions of source code must retain the above copyright

 *     notice, this list of conditions and the following disclaimer.

 *

 *   - Redistributions in binary form must reproduce the above copyright

 *     notice, this list of conditions and the following disclaimer in the

 *     documentation and/or other materials provided with the distribution.

 *

 *   - Neither the name of Oracle nor the names of its

 *     contributors may be used to endorse or promote products derived

 *     from this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS

 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,

 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR

 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF

 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING

 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS

 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

/*

 * This source code is provided to illustrate the usage of a given feature

 * or technique and has been deliberately simplified. Additional steps

 * required for a production-quality application, such as security checks,

 * input validation and proper error handling, might not be present in

 * this sample code.

 */

/* Monitor contention tracking and monitor wait handling. */

/*

 * Monitor's under contention are unique per trace and signature.

 *  Two monitors with the same trace and signature will be treated

 *  the same as far as accumulated contention time.

 *

 * The tls table (or thread table) will be used to store the monitor in

 *   contention or being waited on.

 *

 * Monitor wait activity is emitted as it happens.

 *

 * Monitor contention is tabulated and summarized at dump time.

 *

 */

#include "hprof.h"

typedef struct MonitorKey {

    TraceIndex   trace_index;

    StringIndex  sig_index;

} MonitorKey;

typedef struct MonitorInfo {

    jint         num_hits;

    jlong        contended_time;

} MonitorInfo;

typedef struct IterateInfo {

    MonitorIndex *monitors;

    int           count;

    jlong         total_contended_time;

} IterateInfo;

/* Private internal functions. */

static MonitorKey*

get_pkey(MonitorIndex index)

{

    void * key_ptr;

    int    key_len;

    table_get_key(gdata->monitor_table, index, &key_ptr, &key_len);

    HPROF_ASSERT(key_len==sizeof(MonitorKey));

    HPROF_ASSERT(key_ptr!=NULL);

    return (MonitorKey*)key_ptr;

}

static MonitorInfo *

get_info(MonitorIndex index)

{

    MonitorInfo *       info;

    HPROF_ASSERT(index!=0);

    info = (MonitorInfo*)table_get_info(gdata->monitor_table, index);

    HPROF_ASSERT(info!=NULL);

    return info;

}

static MonitorIndex

find_or_create_entry(JNIEnv *env, TraceIndex trace_index, jobject object)

{

    static MonitorKey empty_key;

    MonitorKey   key;

    MonitorIndex index;

    char        *sig;

    HPROF_ASSERT(object!=NULL);

    WITH_LOCAL_REFS(env, 1) {

        jclass clazz;

        clazz = getObjectClass(env, object);

        getClassSignature(clazz, &sig, NULL);

    } END_WITH_LOCAL_REFS;

    key                    = empty_key;

    key.trace_index        = trace_index;

    key.sig_index = string_find_or_create(sig);

    jvmtiDeallocate(sig);

    index = table_find_or_create_entry(gdata->monitor_table, &key,

                        (int)sizeof(key), NULL, NULL);

    return index;

}

static void

cleanup_item(MonitorIndex index, void *key_ptr, int key_len, void *info_ptr, void *arg)

{

}

static void

list_item(TableIndex index, void *key_ptr, int key_len, void *info_ptr, void *arg)

{

    MonitorInfo *info;

    MonitorKey  *pkey;

    HPROF_ASSERT(key_len==sizeof(MonitorKey));

    HPROF_ASSERT(key_ptr!=NULL);

    HPROF_ASSERT(info_ptr!=NULL);

    pkey = (MonitorKey*)key_ptr;

    info = (MonitorInfo *)info_ptr;

    debug_message(

                "Monitor 0x%08x: trace=0x%08x, sig=0x%08x, "

                "num_hits=%d, contended_time=(%d,%d)\n",

                 index,

                 pkey->trace_index,

                 pkey->sig_index,

                 info->num_hits,

                 jlong_high(info->contended_time),

                 jlong_low(info->contended_time));

}

static void

collect_iterator(MonitorIndex index, void *key_ptr, int key_len, void *info_ptr, void *arg)

{

    MonitorInfo *info;

    IterateInfo *iterate;

    HPROF_ASSERT(key_len==sizeof(MonitorKey));

    HPROF_ASSERT(info_ptr!=NULL);

    HPROF_ASSERT(arg!=NULL);

    iterate = (IterateInfo *)arg;

    info = (MonitorInfo *)info_ptr;

    iterate->monitors[iterate->count++] = index;

    iterate->total_contended_time += info->contended_time;

}

static int

qsort_compare(const void *p_monitor1, const void *p_monitor2)

{

    MonitorInfo * info1;

    MonitorInfo * info2;

    MonitorIndex  monitor1;

    MonitorIndex  monitor2;

    jlong         result;

    HPROF_ASSERT(p_monitor1!=NULL);

    HPROF_ASSERT(p_monitor2!=NULL);

    monitor1 = *(MonitorIndex *)p_monitor1;

    monitor2 = *(MonitorIndex *)p_monitor2;

    info1 = get_info(monitor1);

    info2 = get_info(monitor2);

    result = info2->contended_time - info1->contended_time;

    if (result < (jlong)0) {

        return -1;

    } else if ( result > (jlong)0 ) {

        return 1;

    }

    return info2->num_hits - info1->num_hits;

}

static void

clear_item(MonitorIndex index, void *key_ptr, int key_len, void *info_ptr, void *arg)

{

    MonitorInfo *info;

    HPROF_ASSERT(key_len==sizeof(MonitorKey));

    HPROF_ASSERT(info_ptr!=NULL);

    info = (MonitorInfo *)info_ptr;

    info->contended_time = 0;

}

static TraceIndex

get_trace(TlsIndex tls_index, JNIEnv *env)

{

    TraceIndex trace_index;

    trace_index = tls_get_trace(tls_index, env, gdata->max_trace_depth, JNI_FALSE);

    return trace_index;

}

/* External functions (called from hprof_init.c) */

void

monitor_init(void)

{

    gdata->monitor_table = table_initialize("Monitor",

                            32, 32, 31, (int)sizeof(MonitorInfo));

}

void

monitor_list(void)

{

    debug_message(

        "------------------- Monitor Table ------------------------\n");

    table_walk_items(gdata->monitor_table, &list_item, NULL);

    debug_message(

        "----------------------------------------------------------\n");

}

void

monitor_cleanup(void)

{

    table_cleanup(gdata->monitor_table, &cleanup_item, (void*)NULL);

    gdata->monitor_table = NULL;

}

void

monitor_clear(void)

{

    table_walk_items(gdata->monitor_table, &clear_item, NULL);

}

/* Contended monitor output */

void

monitor_write_contended_time(JNIEnv *env, double cutoff)

{

    int n_entries;

    n_entries = table_element_count(gdata->monitor_table);

    if ( n_entries == 0 ) {

        return;

    }

    rawMonitorEnter(gdata->data_access_lock); {

        IterateInfo iterate;

        int i;

        int n_items;

        jlong total_contended_time;

        /* First write all trace we might refer to. */

        trace_output_unmarked(env);

        /* Looking for an array of monitor index values of interest */

        iterate.monitors = HPROF_MALLOC(n_entries*(int)sizeof(MonitorIndex));

        (void)memset(iterate.monitors, 0, n_entries*(int)sizeof(MonitorIndex));

        /* Get a combined total and an array of monitor index numbers */

        iterate.total_contended_time = 0;

        iterate.count = 0;

        table_walk_items(gdata->monitor_table, &collect_iterator, &iterate);

        /* Sort that list */

        n_entries = iterate.count;

        if ( n_entries > 0 ) {

            qsort(iterate.monitors, n_entries, sizeof(MonitorIndex),

                        &qsort_compare);

        }

        /* Apply the cutoff */

        n_items = 0;

        for (i = 0; i < n_entries; i++) {

            MonitorIndex index;

            MonitorInfo *info;

            double percent;

            index = iterate.monitors[i];

            info = get_info(index);

            percent = (double)info->contended_time /

                      (double)iterate.total_contended_time;

            if (percent < cutoff) {

                break;

            }

            iterate.monitors[n_items++] = index;

        }

        /* Output the items that make sense */

        total_contended_time = iterate.total_contended_time / 1000000;

        if ( n_items > 0 && total_contended_time > 0 ) {

            double accum;

            /* Output the info on this monitor enter site */

            io_write_monitor_header(total_contended_time);

            accum = 0.0;

            for (i = 0; i < n_items; i++) {

                MonitorIndex index;

                MonitorInfo *info;

                MonitorKey *pkey;

                double percent;

                char *sig;

                index = iterate.monitors[i];

                pkey = get_pkey(index);

                info = get_info(index);

                sig = string_get(pkey->sig_index);

                percent = (double)info->contended_time /

                          (double)iterate.total_contended_time * 100.0;

                accum += percent;

                io_write_monitor_elem(i + 1, percent, accum,

                                    info->num_hits,

                                    trace_get_serial_number(pkey->trace_index),

                                    sig);

            }

            io_write_monitor_footer();

        }

        HPROF_FREE(iterate.monitors);

    } rawMonitorExit(gdata->data_access_lock);

}

void

monitor_contended_enter_event(JNIEnv *env, jthread thread, jobject object)

{

    TlsIndex     tls_index;

    MonitorIndex index;

    TraceIndex   trace_index;

    HPROF_ASSERT(env!=NULL);

    HPROF_ASSERT(thread!=NULL);

    HPROF_ASSERT(object!=NULL);

    tls_index =  tls_find_or_create(env, thread);

    HPROF_ASSERT(tls_get_monitor(tls_index)==0);

    trace_index = get_trace(tls_index, env);

    index = find_or_create_entry(env, trace_index, object);

    tls_monitor_start_timer(tls_index);

    tls_set_monitor(tls_index, index);

}

void

monitor_contended_entered_event(JNIEnv* env, jthread thread, jobject object)

{

    TlsIndex     tls_index;

    MonitorInfo *info;

    MonitorIndex index;

    HPROF_ASSERT(env!=NULL);

    HPROF_ASSERT(object!=NULL);

    HPROF_ASSERT(thread!=NULL);

    tls_index = tls_find_or_create(env, thread);

    HPROF_ASSERT(tls_index!=0);

    index     = tls_get_monitor(tls_index);

    HPROF_ASSERT(index!=0);

    info      = get_info(index);

    info->contended_time += tls_monitor_stop_timer(tls_index);

    info->num_hits++;

    tls_set_monitor(tls_index, 0);

}

void

monitor_wait_event(JNIEnv *env, jthread thread, jobject object, jlong timeout)

{

    TlsIndex     tls_index;

    MonitorKey  *pkey;

    MonitorIndex index;

    TraceIndex   trace_index;

    HPROF_ASSERT(env!=NULL);

    HPROF_ASSERT(object!=NULL);

    HPROF_ASSERT(thread!=NULL);

    tls_index =  tls_find_or_create(env, thread);

    HPROF_ASSERT(tls_index!=0);

    HPROF_ASSERT(tls_get_monitor(tls_index)==0);

    trace_index = get_trace(tls_index, env);

    index = find_or_create_entry(env, trace_index, object);

    pkey = get_pkey(index);

    tls_monitor_start_timer(tls_index);

    tls_set_monitor(tls_index, index);

    rawMonitorEnter(gdata->data_access_lock); {

        io_write_monitor_wait(string_get(pkey->sig_index), timeout,

                            tls_get_thread_serial_number(tls_index));

    } rawMonitorExit(gdata->data_access_lock);

}

void

monitor_waited_event(JNIEnv *env, jthread thread,

                                jobject object, jboolean timed_out)

{

    TlsIndex     tls_index;

    MonitorIndex index;

    jlong        time_waited;

    tls_index =  tls_find_or_create(env, thread);

    HPROF_ASSERT(tls_index!=0);

    time_waited = tls_monitor_stop_timer(tls_index);

    index = tls_get_monitor(tls_index);

    if ( index ==0 ) {

        /* As best as I can tell, on Solaris X86 (not SPARC) I sometimes

         *    get a "waited" event on a thread that I have never seen before

         *    at all, so how did I get a WAITED event? Perhaps when I

         *    did the VM_INIT handling, a thread I've never seen had already

         *    done the WAIT (which I never saw?), and now I see this thread

         *    for the first time, and also as it finishes it's WAIT?

         *    Only happening on faster processors?

         */

        tls_set_monitor(tls_index, 0);

        return;

    }

    HPROF_ASSERT(index!=0);

    tls_set_monitor(tls_index, 0);

    if (object == NULL) {

        rawMonitorEnter(gdata->data_access_lock); {

            io_write_monitor_sleep(time_waited,

                        tls_get_thread_serial_number(tls_index));

        } rawMonitorExit(gdata->data_access_lock);

    } else {

        MonitorKey *pkey;

        pkey = get_pkey(index);

        rawMonitorEnter(gdata->data_access_lock); {

            io_write_monitor_waited(string_get(pkey->sig_index), time_waited,

                tls_get_thread_serial_number(tls_index));

        } rawMonitorExit(gdata->data_access_lock);

    }

}