void slabs_cache_update(item* it) {
slabclass_t *p;
unsigned int id;
id = it->slabs_clsid;
if (id > POWER_SMALLEST && id < power_largest) {
p = &slabclass[id];
size_t pos = ((char*) it - (char*) mem_base) / p->size;
assert(pos < p->clock_max);
bv_setbit(p->bitmap, pos, 1);
}
}
item* slabs_cache_evict(unsigned int id) {
slabclass_t *p;
p = &slabclass[id];
size_t max_steps = 10;
bool foundzero = false;
//size_t clock = rand() % p->clock_max;
// slow search until we reach the end of a byte
assert(p->clock < p->clock_max);
while ((p->clock & 0x7) != 0) {
if (bv_getbit(p->bitmap, p->clock)) {
bv_setbit(p->bitmap, p->clock, 0);
} else {
bv_setbit(p->bitmap, p->clock, 1);
foundzero = true;
break;
}
p->clock ++;
if (p->clock >= p->clock_max)
break;
}
if (!foundzero) {
if (p->clock + 64 >= p->clock_max)
p->clock = 0;
uint64_t *val64 = (uint64_t* ) ((char*) (p->bitmap) + p->clock / 8);
for (size_t steps = 0; steps < max_steps; steps ++) {
if (*val64 == (uint64_t) -1) {
*val64 = 0;
val64 ++;
p->clock += 64;
if (p->clock + 64 >= p->clock_max)
p->clock = 0;
continue;
}
else {
// only works for little endian
uint32_t *val32 = (uint32_t*) val64;
if (*val32 == (uint32_t) -1) {
*val32 = 0;
val32 ++;
p->clock += 32;
}
uint16_t *val16 = (uint16_t*) val32;
if (*val16 == (uint16_t) -1) {
*val16 = 0;
val16 ++;
p->clock += 16;
}
uint8_t *val8 = (uint8_t*) val16;
if (*val8 == (uint8_t) -1) {
*val8 = 0;
val8 ++;
p->clock += 8;
}
//k = *val8;
//*val8 &= 1 << k;
p->clock += firstzero[*val8];
//printf("val8 %d\n", *val8);
bv_setbit(p->bitmap, p->clock, 1);
break;
}
}
}
p->clock = (p->clock > p->clock_max) ? 0 : p->clock;
bv_setbit(p->bitmap, p->clock, 1);
assert(p->clock < p->clock_max);
//printf("pos%u\n", p->clock);
//fflush(stdout);
size_t index = p->clock / p->perslab;
size_t offset = p->clock % p->perslab;
p->clock ++;
return (item*) ((char*) (p->slab_list[index]) + p->size * offset);
}
item *slabs_cache_evict(unsigned int id)
{
size_t max_steps = 10, index, offset, steps;
bool foundzero = false;
uint64_t *val64;
uint32_t *val32;
uint16_t *val16;
uint8_t *val8;
item *ret_item;
slabclass_t *p;
p = &slabclass[id];
// slow search until we reach the end of a byte
assert(p->clock < p->clock_max);
while ((p->clock & 0x7) != 0) {
if (bv_getbit(p->bitmap, p->clock) == 1) {
bv_setbit(p->bitmap, p->clock, 0);
} else {
bv_setbit(p->bitmap, p->clock, 1);
foundzero = 0;
break;
}
p->clock++;
if (p->clock >= p->clock_max)
break;
}
if (!foundzero) {
if (p->clock + 64 >= p->clock_max)
p->clock = 0;
val64 = (uint64_t *)((char *)(p->bitmap) + p->clock / 8);
for (steps = 0; steps < max_steps; steps++) {
if (*val64 == (uint64_t)-1) {
*val64 = 0;
val64++;
p->clock += 64;
if (p->clock + 64 >= p->clock_max)
p->clock = 0;
} else {
val32 = (uint32_t *)val64;
if (*val32 == (uint32_t)-1) {
*val32 = 0;
val32++;
p->clock += 32;
}
val16 = (uint16_t *)val32;
if (*val16 == (uint16_t)-1) {
*val16 = 0;
val16++;
p->clock += 16;
}
val8 = (uint8_t *)val16;
if (*val8 == (uint8_t)-1) {
*val8 = 0;
val8++;
p->clock += 8;
}
p->clock += firstzero[*val8];
bv_setbit(p->bitmap, p->clock, 1);
break;
}
}
}
p->clock = (p->clock > p->clock_max) ? 0 : p->clock;
bv_setbit(p->bitmap, p->clock, 1);
assert(p->clock < p->clock_max);
index = p->clock / p->perslab;
offset = p->clock % p->perslab;
p->clock++;
ret_item = (item *)((char *)(p->slab_list[index]) + p->size * offset);
return ret_item;
}
