/* -*- mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*- */
// vim: ft=cpp:expandtab:ts=8:sw=4:softtabstop=4:
#ident "$Id: cachetable-simple-verify.cc 52748 2013-01-31 21:12:42Z leifwalsh $"
#ident "Copyright (c) 2007-2012 Tokutek Inc.  All rights reserved."

#include "test.h"



//
// This test verifies the behavior that originally caused
// #5978 is fixed. Here is what we do. We have four pairs with
// blocknums and fullhashes of 1,2,3,4. The cachetable has only
// two bucket mutexes, so 1 and 3 share a pair mutex, as do 2 and 4.
// We pin all four with expensive write locks. Then, on backgroud threads,
// we call get_and_pin_nonblocking on 3, where the unlockers unpins 2, and
// we call get_and_pin_nonblocking on 4, where the unlockers unpins 1. Run this
// enough times, and we should see a deadlock before the fix, and no deadlock
// after the fix.
//

CACHEFILE f1;
PAIR p3;
PAIR p4;


static int
fetch_three (CACHEFILE f        __attribute__((__unused__)),
       PAIR UU(p),
       int UU(fd),
       CACHEKEY k         __attribute__((__unused__)),
       uint32_t fullhash __attribute__((__unused__)),
       void **value       __attribute__((__unused__)),
       void **dd     __attribute__((__unused__)),
       PAIR_ATTR *sizep        __attribute__((__unused__)),
       int  *dirtyp,
       void *extraargs    __attribute__((__unused__))
       ) {
    *dirtyp = 0;
    *value = NULL;
    *sizep = make_pair_attr(8);
    assert(k.b == 3);
    p3 = p;
    return 0;
}

static int
fetch_four (CACHEFILE f        __attribute__((__unused__)),
       PAIR UU(p),
       int UU(fd),
       CACHEKEY k         __attribute__((__unused__)),
       uint32_t fullhash __attribute__((__unused__)),
       void **value       __attribute__((__unused__)),
       void **dd     __attribute__((__unused__)),
       PAIR_ATTR *sizep        __attribute__((__unused__)),
       int  *dirtyp,
       void *extraargs    __attribute__((__unused__))
       ) {
    *dirtyp = 0;
    *value = NULL;
    *sizep = make_pair_attr(8);
    assert(k.b == 4);
    p4 = p;
    return 0;
}



static void
unpin_four (void* UU(v)) {
    int r = toku_cachetable_unpin_ct_prelocked_no_flush(
        f1,
        p3,
        CACHETABLE_DIRTY,
        make_pair_attr(8)
        );
    assert_zero(r);
}

static void
unpin_three (void* UU(v)) {
    int r = toku_cachetable_unpin_ct_prelocked_no_flush(
        f1,
        p4,
        CACHETABLE_DIRTY,
        make_pair_attr(8)
        );
    assert_zero(r);
}

static void *repin_one(void *UU(arg)) {
    CACHETABLE_WRITE_CALLBACK wc = def_write_callback(NULL);
    struct unlockers unlockers = {true, unpin_four, NULL, NULL};
    void* v1;
    long s1;
    int r = toku_cachetable_get_and_pin_nonblocking(
        f1,
        make_blocknum(1),
        1,
        &v1,
        &s1,
        wc,
        def_fetch,
        def_pf_req_callback,
        def_pf_callback,
        PL_WRITE_EXPENSIVE,
        NULL,
        &unlockers
        );
    assert(r == TOKUDB_TRY_AGAIN);
    return arg;
}


static void *repin_two(void *UU(arg)) {
    CACHETABLE_WRITE_CALLBACK wc = def_write_callback(NULL);
    struct unlockers unlockers = {true, unpin_three, NULL, NULL};
    void* v1;
    long s1;
    int r = toku_cachetable_get_and_pin_nonblocking(
        f1,
        make_blocknum(2),
        2,
        &v1,
        &s1,
        wc,
        def_fetch,
        def_pf_req_callback,
        def_pf_callback,
        PL_WRITE_EXPENSIVE,
        NULL,
        &unlockers
        );
    assert(r == TOKUDB_TRY_AGAIN);
    return arg;
}


static void
cachetable_test (void) {
    const int test_limit = 1000;
    int r;
    toku_pair_list_set_lock_size(2); // set two bucket mutexes
    CACHETABLE ct;
    toku_cachetable_create(&ct, test_limit, ZERO_LSN, NULL_LOGGER);
    const char *fname1 = TOKU_TEST_FILENAME;
    unlink(fname1);
    r = toku_cachetable_openf(&f1, ct, fname1, O_RDWR|O_CREAT, S_IRWXU|S_IRWXG|S_IRWXO); assert(r == 0);

    void* v1;
    long s1;
    CACHETABLE_WRITE_CALLBACK wc = def_write_callback(NULL);

    // bring pairs 1 and 2 into memory, then unpin
    r = toku_cachetable_get_and_pin(f1, make_blocknum(1), 1, &v1, &s1, wc, def_fetch, def_pf_req_callback, def_pf_callback, true, NULL);
    assert_zero(r);
    r = toku_cachetable_get_and_pin(f1, make_blocknum(2), 2, &v1, &s1, wc, def_fetch, def_pf_req_callback, def_pf_callback, true, NULL);
    assert_zero(r);


    // now pin pairs 3 and 4
    r = toku_cachetable_get_and_pin(f1, make_blocknum(3), 3, &v1, &s1, wc, fetch_three, def_pf_req_callback, def_pf_callback, true, NULL);
    assert_zero(r);
    r = toku_cachetable_get_and_pin(f1, make_blocknum(4), 4, &v1, &s1, wc, fetch_four, def_pf_req_callback, def_pf_callback, true, NULL);
    assert_zero(r);

    toku_pthread_t tid1;
    toku_pthread_t tid2;
    r = toku_pthread_create(&tid1, NULL, repin_one, NULL); 
    assert_zero(r);
    r = toku_pthread_create(&tid2, NULL, repin_two, NULL); 
    assert_zero(r);

    // unpin 1 and 2 so tid1 and tid2 can make progress
    usleep(512*1024);
    r = toku_test_cachetable_unpin(f1, make_blocknum(1), 1, CACHETABLE_DIRTY, make_pair_attr(8));
    assert_zero(r);
    r = toku_test_cachetable_unpin(f1, make_blocknum(2), 2, CACHETABLE_DIRTY, make_pair_attr(8));
    assert_zero(r);


    void *ret;
    r = toku_pthread_join(tid1, &ret); 
    assert_zero(r);
    r = toku_pthread_join(tid2, &ret); 
    assert_zero(r);    

    toku_cachetable_verify(ct);
    toku_cachefile_close(&f1, false, ZERO_LSN);
    toku_cachetable_close(&ct);
}

int
test_main(int argc, const char *argv[]) {
    default_parse_args(argc, argv);
    // test ought to run bunch of times in hope of hitting bug
    uint32_t num_test_runs = 30;
    for (uint32_t i = 0; i < num_test_runs; i++) {
        if (verbose) {
            printf("starting test run %" PRIu32 " \n", i);
        }
        cachetable_test();
    }
    return 0;
}