func (p *Backend) allocPool() (err error) {
var (
shmid int
size int
addr uintptr
block *C.struct_cache_block
cache *backendCache
)
cache = p.cache
cache.Lock()
defer cache.Unlock()
shmid, size, err = Shmget(cache.endkey, p.ShmSize, C.IPC_CREAT|0700)
if err != nil {
glog.Errorf(MODULE_NAME+"shmget(%d, %d, ipc_create ) err %s",
cache.endkey, p.ShmSize, err)
return err
}
cache.endkey++
if size != p.ShmSize {
glog.Errorf(MODULE_NAME+"alloc shm size %d want %d, remove and try again",
size, p.ShmSize)
cleanBlocks(cache.endkey)
shmid, _, err = Shmget(cache.endkey, p.ShmSize, C.IPC_CREAT|0700)
if err != nil {
glog.Errorf(MODULE_NAME+"shmget(%d, %d, ipc_create ) err %s",
cache.endkey, p.ShmSize, err)
return err
}
}
addr, err = Shmat(shmid, 0, 0)
if err != nil {
glog.Errorf(MODULE_NAME+"shmat(%d, 0, 0 ) err %s", shmid, err)
return err
}
block = (*C.struct_cache_block)(unsafe.Pointer(addr))
if uint32(block.magic) == p.ShmMagic {
Shmdt(addr)
glog.Errorf(MODULE_NAME+"magic head already set at shmid %d", shmid)
return specs.ErrExist
}
glog.V(5).Infof(MODULE_NAME+"alloc shm segment, endkey 0x%08x shmid %d len(shmaddr) %d",
cache.endkey, shmid, len(cache.shmaddrs))
cache.shmaddrs = append(cache.shmaddrs, addr)
cache.shmids = append(cache.shmids, shmid)
block.magic = C.uint32_t(p.ShmMagic)
block.block_size = C.int(p.ShmSize)
block.cache_entry_nb = C.int(cache.cache_entry_nb)
list := &cache.poolq
list.Lock()
defer list.Unlock()
for i := 0; i < int(block.cache_entry_nb); i++ {
e := &cacheEntry{
e: (*C.struct_cache_entry)(unsafe.Pointer(addr +
uintptr(C.sizeof_struct_cache_block) +
uintptr(i*C.sizeof_struct_cache_entry))),
}
list.head.AddTail(&e.list_data)
}
//list.size += int(block.cache_entry_nb)
//fmt.Printf("poolq.size %d \n", list.size)
return nil
}
