-// btree version threads2i linux futex concurrency version
-// 09 JAN 2014
+// btree version threads2i sched_yield version
+// 24 JAN 2014
// author: karl malbrain, malbrain@cal.berkeley.edu
#ifdef linux
#define _GNU_SOURCE
-#include <linux/futex.h>
-#define SYS_futex 202
#endif
#ifdef unix
#include <sys/mman.h>
#include <errno.h>
#include <pthread.h>
-#include <limits.h>
#else
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
typedef unsigned int uint;
#endif
+#define BT_latchtable 128 // number of latch manager slots
+
#define BT_ro 0x6f72 // ro
#define BT_rw 0x7772 // rw
// mode & definition for latch implementation
enum {
- Mutex = 1 << 0, // the mutex bit
- Write = 1 << 1, // the writers bit
- Share = 1 << 2, // reader count
- PendRd = 1 << 12, // reader contended count
- PendWr = 1 << 22 // writer contended count
+ Mutex = 1,
+ Write = 2,
+ Pending = 4,
+ Share = 8
} LockMode;
-enum {
- QueRd = 1, // reader queue
- QueWr = 2 // writer queue
-} RWQueue;
-
+// exclusive is set for write access
// share is count of read accessors
// grant write lock when share == 0
typedef struct {
- volatile uint mutex:1; // 1 = busy
- volatile uint write:1; // 1 = exclusive
- volatile uint share:10; // count of readers holding locks
- volatile uint readwait:10; // count of readers waiting
- volatile uint writewait:10; // count of writers waiting
-} BtLatch;
+ volatile ushort mutex:1;
+ volatile ushort exclusive:1;
+ volatile ushort pending:1;
+ volatile ushort share:13;
+} BtSpinLatch;
+
+// hash table entries
+
+typedef struct {
+ BtSpinLatch latch[1];
+ volatile ushort slot; // Latch table entry at head of chain
+} BtHashEntry;
+
+// latch manager table structure
typedef struct {
- BtLatch readwr[1]; // read/write page lock
- BtLatch access[1]; // Access Intent/Page delete
- BtLatch parent[1]; // Parent modification
+ BtSpinLatch readwr[1]; // read/write page lock
+ BtSpinLatch access[1]; // Access Intent/Page delete
+ BtSpinLatch parent[1]; // adoption of foster children
+ BtSpinLatch busy[1]; // slot is being moved between chains
+ volatile ushort next; // next entry in hash table chain
+ volatile ushort prev; // prev entry in hash table chain
+ volatile ushort pin; // number of outstanding locks
+ volatile ushort hash; // hash slot entry is under
+ volatile uid page_no; // latch set page number
} BtLatchSet;
// Define the length of the page and key pointers
unsigned char kill:1; // page is being deleted
unsigned char dirty:1; // page has deleted keys
unsigned char right[BtId]; // page number to right
+ BtSlot table[0]; // array of key slots
} *BtPage;
// The memory mapping pool table buffer manager entry
unsigned long long int lru; // number of times accessed
uid basepage; // mapped base page number
char *map; // mapped memory pointer
- uint slot; // slot index in this array
- volatile uint pin; // mapped page pin counter
+ ushort slot; // slot index in this array
+ ushort pin; // mapped page pin counter
void *hashprev; // previous pool entry for the same hash idx
void *hashnext; // next pool entry for the same hash idx
#ifndef unix
#endif
} BtPool;
+// structure for latch manager on ALLOC_page
+
+typedef struct {
+ struct Page alloc[2]; // next & free page_nos in right ptr
+ BtSpinLatch lock[1]; // allocation area lite latch
+ ushort latchdeployed; // highest number of latch entries deployed
+ ushort nlatchpage; // number of latch pages at BT_latch
+ ushort latchtotal; // number of page latch entries
+ ushort latchhash; // number of latch hash table slots
+ ushort latchvictim; // next latch entry to examine
+ BtHashEntry table[0]; // the hash table
+} BtLatchMgr;
+
// The object structure for Btree access
typedef struct {
#else
HANDLE idx;
#endif
- volatile uint poolcnt; // highest page pool node in use
+ ushort poolcnt; // highest page pool node in use
+ ushort poolmax; // highest page pool node allocated
+ ushort poolmask; // total number of pages in mmap segment - 1
+ ushort hashsize; // size of Hash Table for pool entries
volatile uint evicted; // last evicted hash table slot
- uint poolmax; // highest page pool node allocated
- uint poolmask; // total size of pages in mmap segment - 1
- uint hashsize; // size of Hash Table for pool entries
ushort *hash; // pool index for hash entries
- BtLatch *latch; // latches for hash table slots
+ BtSpinLatch *latch; // latches for hash table slots
+ BtLatchMgr *latchmgr; // mapped latch page from allocation page
+ BtLatchSet *latchsets; // mapped latch set from latch pages
BtPool *pool; // memory pool page segments
+#ifndef unix
+ HANDLE halloc; // allocation and latch table handle
+#endif
} BtMgr;
typedef struct {
BtMgr *mgr; // buffer manager for thread
- BtPage temp; // temporary frame buffer (memory mapped/file IO)
- BtPage alloc; // frame buffer for alloc page ( mapped to page 0 )
BtPage cursor; // cached frame for start/next (never mapped)
BtPage frame; // spare frame for the page split (never mapped)
- BtPage zero; // page of zeroes to extend the file (never mapped)
- BtPage page; // current page mapped from file
+ BtPage zero; // page frame for zeroes at end of file
+ BtPage page; // current page
uid page_no; // current page number
uid cursor_page; // current cursor page number
+ BtLatchSet *set; // current page latch set
+ BtPool *pool; // current page pool
unsigned char *mem; // frame, cursor, page memory buffer
+ int found; // last delete or insert was found
int err; // last error
} BtDb;
extern uint bt_tod (BtDb *bt, uint slot);
// BTree page number constants
-#define ALLOC_page 0
-#define ROOT_page 1
-#define LEAF_page 2
+#define ALLOC_page 0 // allocation & lock manager hash table
+#define ROOT_page 1 // root of the btree
+#define LEAF_page 2 // first page of leaves
+#define LATCH_page 3 // pages for lock manager
// Number of levels to create in a new BTree
// Access macros to address slot and key values from the page
-#define slotptr(page, slot) (((BtSlot *)(page+1)) + (slot-1))
+#define slotptr(page, slot) (page->table + slot-1)
#define keyptr(page, slot) ((BtKey)((unsigned char*)(page) + slotptr(page, slot)->off))
void bt_putid(unsigned char *dest, uid id)
return id;
}
+// Latch Manager
+
+// wait until write lock mode is clear
+// and add 1 to the share count
+
+void bt_spinreadlock(BtSpinLatch *latch)
+{
+ushort prev;
+
+ do {
+ // obtain latch mutex
+#ifdef unix
+ if( __sync_fetch_and_or((ushort *)latch, Mutex) & Mutex )
+ continue;
+#else
+ if( prev = _InterlockedOr16((ushort *)latch, Mutex) & Mutex )
+ continue;
+#endif
+ // see if exclusive request is granted or pending
+
+ if( prev = !(latch->exclusive | latch->pending) )
+#ifdef unix
+ __sync_fetch_and_add((ushort *)latch, Share);
+#else
+ _InterlockedExchangeAdd16 ((ushort *)latch, Share);
+#endif
+
+#ifdef unix
+ __sync_fetch_and_and ((ushort *)latch, ~Mutex);
+#else
+ _InterlockedAnd16((ushort *)latch, ~Mutex);
+#endif
+
+ if( prev )
+ return;
+#ifdef unix
+ } while( sched_yield(), 1 );
+#else
+ } while( SwitchToThread(), 1 );
+#endif
+}
+
+// wait for other read and write latches to relinquish
+
+void bt_spinwritelock(BtSpinLatch *latch)
+{
+ do {
+#ifdef unix
+ if( __sync_fetch_and_or((ushort *)latch, Mutex | Pending) & Mutex )
+ continue;
+#else
+ if( _InterlockedOr16((ushort *)latch, Mutex | Pending) & Mutex )
+ continue;
+#endif
+ if( !(latch->share | latch->exclusive) ) {
+#ifdef unix
+ __sync_fetch_and_or((ushort *)latch, Write);
+ __sync_fetch_and_and ((ushort *)latch, ~(Mutex | Pending));
+#else
+ _InterlockedOr16((ushort *)latch, Write);
+ _InterlockedAnd16((ushort *)latch, ~(Mutex | Pending));
+#endif
+ return;
+ }
+
+#ifdef unix
+ __sync_fetch_and_and ((ushort *)latch, ~Mutex);
+#else
+ _InterlockedAnd16((ushort *)latch, ~Mutex);
+#endif
+
+#ifdef unix
+ } while( sched_yield(), 1 );
+#else
+ } while( SwitchToThread(), 1 );
+#endif
+}
+
+// try to obtain write lock
+
+// return 1 if obtained,
+// 0 otherwise
+
+int bt_spinwritetry(BtSpinLatch *latch)
+{
+ushort prev;
+
+#ifdef unix
+ if( prev = __sync_fetch_and_or((ushort *)latch, Mutex), prev & Mutex )
+ return 0;
+#else
+ if( prev = _InterlockedOr16((ushort *)latch, Mutex), prev & Mutex )
+ return 0;
+#endif
+ // take write access if all bits are clear
+
+ if( !prev )
+#ifdef unix
+ __sync_fetch_and_or ((ushort *)latch, Write);
+#else
+ _InterlockedOr16((ushort *)latch, Write);
+#endif
+
+#ifdef unix
+ __sync_fetch_and_and ((ushort *)latch, ~Mutex);
+#else
+ _InterlockedAnd16((ushort *)latch, ~Mutex);
+#endif
+ return !prev;
+}
+
+// clear write mode
+
+void bt_spinreleasewrite(BtSpinLatch *latch)
+{
+#ifdef unix
+ __sync_fetch_and_and ((ushort *)latch, ~Write);
+#else
+ _InterlockedAnd16((ushort *)latch, ~Write);
+#endif
+}
+
+// decrement reader count
+
+void bt_spinreleaseread(BtSpinLatch *latch)
+{
+#ifdef unix
+ __sync_fetch_and_add((ushort *)latch, -Share);
+#else
+ _InterlockedExchangeAdd16 ((ushort *)latch, -Share);
+#endif
+}
+
+// link latch table entry into latch hash table
+
+void bt_latchlink (BtDb *bt, ushort hashidx, ushort victim, uid page_no)
+{
+BtLatchSet *set = bt->mgr->latchsets + victim;
+
+ if( set->next = bt->mgr->latchmgr->table[hashidx].slot )
+ bt->mgr->latchsets[set->next].prev = victim;
+
+ bt->mgr->latchmgr->table[hashidx].slot = victim;
+ set->page_no = page_no;
+ set->hash = hashidx;
+ set->prev = 0;
+}
+
+// release latch pin
+
+void bt_unpinlatch (BtLatchSet *set)
+{
+#ifdef unix
+ __sync_fetch_and_add(&set->pin, -1);
+#else
+ _InterlockedDecrement16 (&set->pin);
+#endif
+}
+
+// find existing latchset or inspire new one
+// return with latchset pinned
+
+BtLatchSet *bt_pinlatch (BtDb *bt, uid page_no)
+{
+ushort hashidx = page_no % bt->mgr->latchmgr->latchhash;
+ushort slot, avail = 0, victim, idx;
+BtLatchSet *set;
+
+ // obtain read lock on hash table entry
+
+ bt_spinreadlock(bt->mgr->latchmgr->table[hashidx].latch);
+
+ if( slot = bt->mgr->latchmgr->table[hashidx].slot ) do
+ {
+ set = bt->mgr->latchsets + slot;
+ if( page_no == set->page_no )
+ break;
+ } while( slot = set->next );
+
+ if( slot ) {
+#ifdef unix
+ __sync_fetch_and_add(&set->pin, 1);
+#else
+ _InterlockedIncrement16 (&set->pin);
+#endif
+ }
+
+ bt_spinreleaseread (bt->mgr->latchmgr->table[hashidx].latch);
+
+ if( slot )
+ return set;
+
+ // try again, this time with write lock
+
+ bt_spinwritelock(bt->mgr->latchmgr->table[hashidx].latch);
+
+ if( slot = bt->mgr->latchmgr->table[hashidx].slot ) do
+ {
+ set = bt->mgr->latchsets + slot;
+ if( page_no == set->page_no )
+ break;
+ if( !set->pin && !avail )
+ avail = slot;
+ } while( slot = set->next );
+
+ // found our entry, or take over an unpinned one
+
+ if( slot || (slot = avail) ) {
+ set = bt->mgr->latchsets + slot;
+#ifdef unix
+ __sync_fetch_and_add(&set->pin, 1);
+#else
+ _InterlockedIncrement16 (&set->pin);
+#endif
+ set->page_no = page_no;
+ bt_spinreleasewrite(bt->mgr->latchmgr->table[hashidx].latch);
+ return set;
+ }
+
+ // see if there are any unused entries
+#ifdef unix
+ victim = __sync_fetch_and_add (&bt->mgr->latchmgr->latchdeployed, 1) + 1;
+#else
+ victim = _InterlockedIncrement16 (&bt->mgr->latchmgr->latchdeployed);
+#endif
+
+ if( victim < bt->mgr->latchmgr->latchtotal ) {
+ set = bt->mgr->latchsets + victim;
+#ifdef unix
+ __sync_fetch_and_add(&set->pin, 1);
+#else
+ _InterlockedIncrement16 (&set->pin);
+#endif
+ bt_latchlink (bt, hashidx, victim, page_no);
+ bt_spinreleasewrite (bt->mgr->latchmgr->table[hashidx].latch);
+ return set;
+ }
+
+#ifdef unix
+ victim = __sync_fetch_and_add (&bt->mgr->latchmgr->latchdeployed, -1);
+#else
+ victim = _InterlockedDecrement16 (&bt->mgr->latchmgr->latchdeployed);
+#endif
+ // find and reuse previous lock entry
+
+ while( 1 ) {
+#ifdef unix
+ victim = __sync_fetch_and_add(&bt->mgr->latchmgr->latchvictim, 1);
+#else
+ victim = _InterlockedIncrement16 (&bt->mgr->latchmgr->latchvictim) - 1;
+#endif
+ // we don't use slot zero
+
+ if( victim %= bt->mgr->latchmgr->latchtotal )
+ set = bt->mgr->latchsets + victim;
+ else
+ continue;
+
+ // take control of our slot
+ // from other threads
+
+ if( set->pin || !bt_spinwritetry (set->busy) )
+ continue;
+
+ idx = set->hash;
+
+ // try to get write lock on hash chain
+ // skip entry if not obtained
+ // or has outstanding locks
+
+ if( !bt_spinwritetry (bt->mgr->latchmgr->table[idx].latch) ) {
+ bt_spinreleasewrite (set->busy);
+ continue;
+ }
+
+ if( set->pin ) {
+ bt_spinreleasewrite (set->busy);
+ bt_spinreleasewrite (bt->mgr->latchmgr->table[idx].latch);
+ continue;
+ }
+
+ // unlink our available victim from its hash chain
+
+ if( set->prev )
+ bt->mgr->latchsets[set->prev].next = set->next;
+ else
+ bt->mgr->latchmgr->table[idx].slot = set->next;
+
+ if( set->next )
+ bt->mgr->latchsets[set->next].prev = set->prev;
+
+ bt_spinreleasewrite (bt->mgr->latchmgr->table[idx].latch);
+#ifdef unix
+ __sync_fetch_and_add(&set->pin, 1);
+#else
+ _InterlockedIncrement16 (&set->pin);
+#endif
+ bt_latchlink (bt, hashidx, victim, page_no);
+ bt_spinreleasewrite (bt->mgr->latchmgr->table[hashidx].latch);
+ bt_spinreleasewrite (set->busy);
+ return set;
+ }
+}
+
void bt_mgrclose (BtMgr *mgr)
{
BtPool *pool;
#endif
}
+#ifdef unix
+ munmap (mgr->latchsets, mgr->latchmgr->nlatchpage * mgr->page_size);
+ munmap (mgr->latchmgr, mgr->page_size);
+#else
+ FlushViewOfFile(mgr->latchmgr, 0);
+ UnmapViewOfFile(mgr->latchmgr);
+ CloseHandle(mgr->halloc);
+#endif
#ifdef unix
close (mgr->idx);
free (mgr->pool);
BtMgr *bt_mgr (char *name, uint mode, uint bits, uint poolmax, uint segsize, uint hashsize)
{
-uint lvl, attr, cacheblk, last;
-BtPage alloc;
-int lockmode;
+uint lvl, attr, cacheblk, last, slot, idx;
+uint nlatchpage, latchhash;
+BtLatchMgr *latchmgr;
off64_t size;
uint amt[1];
BtMgr* mgr;
BtKey key;
+int flag;
#ifndef unix
SYSTEM_INFO sysinfo[1];
#ifdef unix
mgr = calloc (1, sizeof(BtMgr));
- switch (mode & 0x7fff)
- {
- case BT_rw:
- mgr->idx = open ((char*)name, O_RDWR | O_CREAT, 0666);
- lockmode = 1;
- break;
+ mgr->idx = open ((char*)name, O_RDWR | O_CREAT, 0666);
- case BT_ro:
- default:
- mgr->idx = open ((char*)name, O_RDONLY);
- lockmode = 0;
- break;
- }
if( mgr->idx == -1 )
return free(mgr), NULL;
#else
mgr = GlobalAlloc (GMEM_FIXED|GMEM_ZEROINIT, sizeof(BtMgr));
attr = FILE_ATTRIBUTE_NORMAL;
- switch (mode & 0x7fff)
- {
- case BT_rw:
- mgr->idx = CreateFile(name, GENERIC_READ| GENERIC_WRITE, FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_ALWAYS, attr, NULL);
- lockmode = 1;
- break;
+ mgr->idx = CreateFile(name, GENERIC_READ| GENERIC_WRITE, FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_ALWAYS, attr, NULL);
- case BT_ro:
- default:
- mgr->idx = CreateFile(name, GENERIC_READ, FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_EXISTING, attr, NULL);
- lockmode = 0;
- break;
- }
if( mgr->idx == INVALID_HANDLE_VALUE )
return GlobalFree(mgr), NULL;
#endif
#ifdef unix
- alloc = malloc (BT_maxpage);
+ latchmgr = malloc (BT_maxpage);
*amt = 0;
// read minimum page size to get root info
if( size = lseek (mgr->idx, 0L, 2) ) {
- if( pread(mgr->idx, alloc, BT_minpage, 0) == BT_minpage )
- bits = alloc->bits;
+ if( pread(mgr->idx, latchmgr, BT_minpage, 0) == BT_minpage )
+ bits = latchmgr->alloc->bits;
else
- return free(mgr), free(alloc), NULL;
+ return free(mgr), free(latchmgr), NULL;
} else if( mode == BT_ro )
- return bt_mgrclose (mgr), NULL;
+ return free(latchmgr), bt_mgrclose (mgr), NULL;
#else
- alloc = VirtualAlloc(NULL, BT_maxpage, MEM_COMMIT, PAGE_READWRITE);
+ latchmgr = VirtualAlloc(NULL, BT_maxpage, MEM_COMMIT, PAGE_READWRITE);
size = GetFileSize(mgr->idx, amt);
if( size || *amt ) {
- if( !ReadFile(mgr->idx, (char *)alloc, BT_minpage, amt, NULL) )
+ if( !ReadFile(mgr->idx, (char *)latchmgr, BT_minpage, amt, NULL) )
return bt_mgrclose (mgr), NULL;
- bits = alloc->bits;
+ bits = latchmgr->alloc->bits;
} else if( mode == BT_ro )
return bt_mgrclose (mgr), NULL;
#endif
#ifdef unix
mgr->pool = calloc (poolmax, sizeof(BtPool));
mgr->hash = calloc (hashsize, sizeof(ushort));
- mgr->latch = calloc (hashsize, sizeof(BtLatch));
+ mgr->latch = calloc (hashsize, sizeof(BtSpinLatch));
mgr->pooladvise = calloc (poolmax, (mgr->poolmask + 8) / 8);
#else
mgr->pool = GlobalAlloc (GMEM_FIXED|GMEM_ZEROINIT, poolmax * sizeof(BtPool));
mgr->hash = GlobalAlloc (GMEM_FIXED|GMEM_ZEROINIT, hashsize * sizeof(ushort));
- mgr->latch = GlobalAlloc (GMEM_FIXED|GMEM_ZEROINIT, hashsize * sizeof(BtLatch));
+ mgr->latch = GlobalAlloc (GMEM_FIXED|GMEM_ZEROINIT, hashsize * sizeof(BtSpinLatch));
#endif
if( size || *amt )
- goto mgrxit;
+ goto mgrlatch;
+
+ // initialize an empty b-tree with latch page, root page, page of leaves
+ // and page(s) of latches
+
+ memset (latchmgr, 0, 1 << bits);
+ nlatchpage = BT_latchtable / (mgr->page_size / sizeof(BtLatchSet)) + 1;
+ bt_putid(latchmgr->alloc->right, MIN_lvl+1+nlatchpage);
+ latchmgr->alloc->bits = mgr->page_bits;
+
+ latchmgr->nlatchpage = nlatchpage;
+ latchmgr->latchtotal = nlatchpage * (mgr->page_size / sizeof(BtLatchSet));
+
+ // initialize latch manager
- // initializes an empty b-tree with root page and page of leaves
+ latchhash = (mgr->page_size - sizeof(BtLatchMgr)) / sizeof(BtHashEntry);
- memset (alloc, 0, 1 << bits);
- bt_putid(alloc->right, MIN_lvl+1);
- alloc->bits = mgr->page_bits;
+ // size of hash table = total number of latchsets
+
+ if( latchhash > latchmgr->latchtotal )
+ latchhash = latchmgr->latchtotal;
+
+ latchmgr->latchhash = latchhash;
#ifdef unix
- if( write (mgr->idx, alloc, mgr->page_size) < mgr->page_size )
+ if( write (mgr->idx, latchmgr, mgr->page_size) < mgr->page_size )
return bt_mgrclose (mgr), NULL;
#else
- if( !WriteFile (mgr->idx, (char *)alloc, mgr->page_size, amt, NULL) )
+ if( !WriteFile (mgr->idx, (char *)latchmgr, mgr->page_size, amt, NULL) )
return bt_mgrclose (mgr), NULL;
if( *amt < mgr->page_size )
return bt_mgrclose (mgr), NULL;
#endif
- memset (alloc, 0, 1 << bits);
- alloc->bits = mgr->page_bits;
+ memset (latchmgr, 0, 1 << bits);
+ latchmgr->alloc->bits = mgr->page_bits;
for( lvl=MIN_lvl; lvl--; ) {
- slotptr(alloc, 1)->off = mgr->page_size - 3;
- bt_putid(slotptr(alloc, 1)->id, lvl ? MIN_lvl - lvl + 1 : 0); // next(lower) page number
- key = keyptr(alloc, 1);
+ slotptr(latchmgr->alloc, 1)->off = mgr->page_size - 3;
+ bt_putid(slotptr(latchmgr->alloc, 1)->id, lvl ? MIN_lvl - lvl + 1 : 0); // next(lower) page number
+ key = keyptr(latchmgr->alloc, 1);
key->len = 2; // create stopper key
key->key[0] = 0xff;
key->key[1] = 0xff;
- alloc->min = mgr->page_size - 3;
- alloc->lvl = lvl;
- alloc->cnt = 1;
- alloc->act = 1;
+ latchmgr->alloc->min = mgr->page_size - 3;
+ latchmgr->alloc->lvl = lvl;
+ latchmgr->alloc->cnt = 1;
+ latchmgr->alloc->act = 1;
#ifdef unix
- if( write (mgr->idx, alloc, mgr->page_size) < mgr->page_size )
+ if( write (mgr->idx, latchmgr, mgr->page_size) < mgr->page_size )
return bt_mgrclose (mgr), NULL;
#else
- if( !WriteFile (mgr->idx, (char *)alloc, mgr->page_size, amt, NULL) )
+ if( !WriteFile (mgr->idx, (char *)latchmgr, mgr->page_size, amt, NULL) )
return bt_mgrclose (mgr), NULL;
if( *amt < mgr->page_size )
#endif
}
- // create empty page area by writing last page of first
- // segment area (other pages are zeroed by O/S)
+ // clear out latch manager locks
+ // and rest of pages to round out segment
- if( mgr->poolmask ) {
- memset(alloc, 0, mgr->page_size);
- last = mgr->poolmask;
-
- while( last < MIN_lvl + 1 )
- last += mgr->poolmask + 1;
+ memset(latchmgr, 0, mgr->page_size);
+ last = MIN_lvl + 1;
+ while( last <= ((MIN_lvl + 1 + nlatchpage) | mgr->poolmask) ) {
#ifdef unix
- pwrite(mgr->idx, alloc, mgr->page_size, last << mgr->page_bits);
+ pwrite(mgr->idx, latchmgr, mgr->page_size, last << mgr->page_bits);
#else
SetFilePointer (mgr->idx, last << mgr->page_bits, NULL, FILE_BEGIN);
- if( !WriteFile (mgr->idx, (char *)alloc, mgr->page_size, amt, NULL) )
+ if( !WriteFile (mgr->idx, (char *)latchmgr, mgr->page_size, amt, NULL) )
return bt_mgrclose (mgr), NULL;
if( *amt < mgr->page_size )
return bt_mgrclose (mgr), NULL;
#endif
+ last++;
}
-mgrxit:
+mgrlatch:
+#ifdef unix
+ flag = PROT_READ | PROT_WRITE;
+ mgr->latchmgr = mmap (0, mgr->page_size, flag, MAP_SHARED, mgr->idx, ALLOC_page * mgr->page_size);
+ if( mgr->latchmgr == MAP_FAILED )
+ return bt_mgrclose (mgr), NULL;
+ mgr->latchsets = (BtLatchSet *)mmap (0, mgr->latchmgr->nlatchpage * mgr->page_size, flag, MAP_SHARED, mgr->idx, LATCH_page * mgr->page_size);
+ if( mgr->latchsets == MAP_FAILED )
+ return bt_mgrclose (mgr), NULL;
+#else
+ flag = PAGE_READWRITE;
+ mgr->halloc = CreateFileMapping(mgr->idx, NULL, flag, 0, (BT_latchtable / (mgr->page_size / sizeof(BtLatchSet)) + 1 + LATCH_page) * mgr->page_size, NULL);
+ if( !mgr->halloc )
+ return bt_mgrclose (mgr), NULL;
+
+ flag = FILE_MAP_WRITE;
+ mgr->latchmgr = MapViewOfFile(mgr->halloc, flag, 0, 0, (BT_latchtable / (mgr->page_size / sizeof(BtLatchSet)) + 1 + LATCH_page) * mgr->page_size);
+ if( !mgr->latchmgr )
+ return GetLastError(), bt_mgrclose (mgr), NULL;
+
+ mgr->latchsets = (void *)((char *)mgr->latchmgr + LATCH_page * mgr->page_size);
+#endif
+
#ifdef unix
- free (alloc);
+ free (latchmgr);
#else
- VirtualFree (alloc, 0, MEM_RELEASE);
+ VirtualFree (latchmgr, 0, MEM_RELEASE);
#endif
return mgr;
}
return 0;
}
-// Latch Manager
-
-int sys_futex(void *addr1, int op, int val1, struct timespec *timeout, void *addr2, int val3)
-{
- return syscall(SYS_futex, addr1, op, val1, timeout, addr2, val3);
-}
-
-// wait until write lock mode is clear
-// and add 1 to the share count
-
-void bt_readlock(BtLatch *latch, int private)
-{
-uint prev;
-
- if( private )
- private = FUTEX_PRIVATE_FLAG;
-
- while( 1 ) {
- // obtain latch mutex
- if( __sync_fetch_and_or((uint *)latch, Mutex) & Mutex ) {
- sched_yield();
- continue;
- }
-
- // wait for writers to clear
- // increment read waiters and wait
-
- if( latch->write || latch->writewait ) {
- __sync_fetch_and_add ((uint *)latch, PendRd);
- prev = __sync_fetch_and_and ((uint *)latch, ~Mutex) & ~Mutex;
- sys_futex( (uint *)latch, FUTEX_WAIT_BITSET | private, prev, NULL, NULL, QueRd );
- __sync_fetch_and_sub ((uint *)latch, PendRd);
- continue;
- }
-
- // increment reader lock count
- // and release latch mutex
-
- __sync_fetch_and_add ((uint *)latch, Share);
- __sync_fetch_and_and ((uint *)latch, ~Mutex);
- return;
- }
-}
-
-// wait for other read and write latches to relinquish
-
-void bt_writelock(BtLatch *latch, int private)
-{
-uint prev;
-
- if( private )
- private = FUTEX_PRIVATE_FLAG;
-
- while( 1 ) {
- // obtain latch mutex
- if( __sync_fetch_and_or((uint *)latch, Mutex) & Mutex ) {
- sched_yield();
- continue;
- }
-
- // wait for write and reader count to clear
-
- if( latch->write || latch->share ) {
- __sync_fetch_and_add ((uint *)latch, PendWr);
- prev = __sync_fetch_and_and ((uint *)latch, ~Mutex) & ~Mutex;
- sys_futex( (uint *)latch, FUTEX_WAIT_BITSET | private, prev, NULL, NULL, QueWr );
- __sync_fetch_and_sub ((uint *)latch, PendWr);
- continue;
- }
-
- // take write mutex
- // release latch mutex
-
- __sync_fetch_and_or ((uint *)latch, Write);
- __sync_fetch_and_and ((uint *)latch, ~Mutex);
- return;
- }
-}
-
-// try to obtain write lock
-
-// return 1 if obtained,
-// 0 otherwise
-
-int bt_writetry(BtLatch *latch)
-{
-int ans;
-
- // try for mutex,
- // abandon request if not taken
-
- if( __sync_fetch_and_or((uint *)latch, Mutex) & Mutex )
- return 0;
-
- // see if write mode is available
-
- if( !latch->write && !latch->share ) {
- __sync_fetch_and_or ((uint *)latch, Write);
- ans = 1;
- } else
- ans = 0;
-
- // release latch mutex
-
- __sync_fetch_and_and ((uint *)latch, ~Mutex);
- return ans;
-}
-
-// clear write lock
-
-void bt_releasewrite(BtLatch *latch, int private)
-{
- if( private )
- private = FUTEX_PRIVATE_FLAG;
-
- // obtain latch mutex
-
- while( __sync_fetch_and_or((uint *)latch, Mutex) & Mutex )
- sched_yield();
-
- __sync_fetch_and_and ((uint *)latch, ~Write);
-
- // favor writers
-
- if( latch->writewait )
- if( sys_futex( (uint *)latch, FUTEX_WAKE_BITSET | private, 1, NULL, NULL, QueWr ) )
- goto wakexit;
-
- if( latch->readwait )
- sys_futex( (uint *)latch, FUTEX_WAKE_BITSET | private, INT_MAX, NULL, NULL, QueRd );
-
- // release latch mutex
-
-wakexit:
- __sync_fetch_and_and ((uint *)latch, ~Mutex);
-}
-
-// decrement reader count
-
-void bt_releaseread(BtLatch *latch, int private)
-{
- if( private )
- private = FUTEX_PRIVATE_FLAG;
-
- // obtain latch mutex
-
- while( __sync_fetch_and_or((uint *)latch, Mutex) & Mutex )
- sched_yield();
-
- __sync_fetch_and_sub ((uint *)latch, Share);
-
- // wake waiting writers
-
- if( !latch->share && latch->writewait )
- sys_futex( (uint *)latch, FUTEX_WAKE_BITSET | private, 1, NULL, NULL, QueWr );
-
- // release latch mutex
-
- __sync_fetch_and_and ((uint *)latch, ~Mutex);
-}
-
// Buffer Pool mgr
// find segment in pool
return bt->err = 0;
}
+// calculate page within pool
+
+BtPage bt_page (BtDb *bt, BtPool *pool, uid page_no)
+{
+uint subpage = (uint)(page_no & bt->mgr->poolmask); // page within mapping
+BtPage page;
+
+ page = (BtPage)(pool->map + (subpage << bt->mgr->page_bits));
+#ifdef unix
+ {
+ uint idx = subpage / 8;
+ uint bit = subpage % 8;
+
+ if( ~((bt->mgr->pooladvise + pool->slot * ((bt->mgr->poolmask + 8)/8))[idx] >> bit) & 1 ) {
+ madvise (page, bt->mgr->page_size, MADV_WILLNEED);
+ (bt->mgr->pooladvise + pool->slot * ((bt->mgr->poolmask + 8)/8))[idx] |= 1 << bit;
+ }
+ }
+#endif
+ return page;
+}
+
+// release pool pin
+
+void bt_unpinpool (BtPool *pool)
+{
+#ifdef unix
+ __sync_fetch_and_add(&pool->pin, -1);
+#else
+ _InterlockedDecrement16 (&pool->pin);
+#endif
+}
+
// find or place requested page in segment-pool
// return pool table entry, incrementing pin
-BtPool *bt_pinpage(BtDb *bt, uid page_no)
+BtPool *bt_pinpool(BtDb *bt, uid page_no)
{
BtPool *pool, *node, *next;
uint slot, idx, victim;
// lock hash table chain
idx = (uint)(page_no >> bt->mgr->seg_bits) % bt->mgr->hashsize;
- bt_readlock (&bt->mgr->latch[idx], 1);
+ bt_spinreadlock (&bt->mgr->latch[idx]);
// look up in hash table
#ifdef unix
__sync_fetch_and_add(&pool->pin, 1);
#else
- _InterlockedIncrement (&pool->pin);
+ _InterlockedIncrement16 (&pool->pin);
#endif
- bt_releaseread (&bt->mgr->latch[idx], 1);
+ bt_spinreleaseread (&bt->mgr->latch[idx]);
pool->lru++;
return pool;
}
// upgrade to write lock
- bt_releaseread (&bt->mgr->latch[idx], 1);
- bt_writelock (&bt->mgr->latch[idx], 1);
+ bt_spinreleaseread (&bt->mgr->latch[idx]);
+ bt_spinwritelock (&bt->mgr->latch[idx]);
// try to find page in pool with write lock
#ifdef unix
__sync_fetch_and_add(&pool->pin, 1);
#else
- _InterlockedIncrement (&pool->pin);
+ _InterlockedIncrement16 (&pool->pin);
#endif
- bt_releasewrite (&bt->mgr->latch[idx], 1);
+ bt_spinreleasewrite (&bt->mgr->latch[idx]);
pool->lru++;
return pool;
}
#ifdef unix
slot = __sync_fetch_and_add(&bt->mgr->poolcnt, 1);
#else
- slot = _InterlockedIncrement (&bt->mgr->poolcnt) - 1;
+ slot = _InterlockedIncrement16 (&bt->mgr->poolcnt) - 1;
#endif
if( ++slot < bt->mgr->poolmax ) {
#ifdef unix
__sync_fetch_and_add(&pool->pin, 1);
#else
- _InterlockedIncrement (&pool->pin);
+ _InterlockedIncrement16 (&pool->pin);
#endif
- bt_releasewrite (&bt->mgr->latch[idx], 1);
+ bt_spinreleasewrite (&bt->mgr->latch[idx]);
return pool;
}
#ifdef unix
__sync_fetch_and_add(&bt->mgr->poolcnt, -1);
#else
- _InterlockedDecrement (&bt->mgr->poolcnt);
+ _InterlockedDecrement16 (&bt->mgr->poolcnt);
#endif
while( 1 ) {
// try to get write lock
// skip entry if not obtained
- if( !bt_writetry (&bt->mgr->latch[victim]) )
+ if( !bt_spinwritetry (&bt->mgr->latch[victim]) )
continue;
// if pool entry is empty
// skip this entry
if( !(pool = bt_findlru(bt, bt->mgr->hash[victim])) ) {
- bt_releasewrite (&bt->mgr->latch[victim], 1);
+ bt_spinreleasewrite (&bt->mgr->latch[victim]);
continue;
}
if( node = pool->hashnext )
node->hashprev = pool->hashprev;
- bt_releasewrite (&bt->mgr->latch[victim], 1);
+ bt_spinreleasewrite (&bt->mgr->latch[victim]);
// remove old file mapping
#ifdef unix
#ifdef unix
__sync_fetch_and_add(&pool->pin, 1);
#else
- _InterlockedIncrement (&pool->pin);
+ _InterlockedIncrement16 (&pool->pin);
#endif
- bt_releasewrite (&bt->mgr->latch[idx], 1);
+ bt_spinreleasewrite (&bt->mgr->latch[idx]);
return pool;
}
}
// place write, read, or parent lock on requested page_no.
-// pin to buffer pool and return page pointer
-BTERR bt_lockpage(BtDb *bt, uid page_no, BtLock mode, BtPage *pageptr)
+void bt_lockpage(BtLock mode, BtLatchSet *set)
{
-uint subpage;
-BtPool *pool;
-BtPage page;
-
- // find/create maping in pool table
- // and pin our pool slot
-
- if( pool = bt_pinpage(bt, page_no) )
- subpage = (uint)(page_no & bt->mgr->poolmask); // page within mapping
- else
- return bt->err;
-
- page = (BtPage)(pool->map + (subpage << bt->mgr->page_bits));
-#ifdef unix
- {
- uint idx = subpage / 8;
- uint bit = subpage % 8;
-
- if( ~((bt->mgr->pooladvise + pool->slot * ((bt->mgr->poolmask + 8)/8))[idx] >> bit) & 1 ) {
- madvise (page, bt->mgr->page_size, MADV_WILLNEED);
- (bt->mgr->pooladvise + pool->slot * ((bt->mgr->poolmask + 8)/8))[idx] |= 1 << bit;
- }
- }
-#endif
-
switch( mode ) {
case BtLockRead:
- bt_readlock (page->latch->readwr, 0);
+ bt_spinreadlock (set->readwr);
break;
case BtLockWrite:
- bt_writelock (page->latch->readwr, 0);
+ bt_spinwritelock (set->readwr);
break;
case BtLockAccess:
- bt_readlock (page->latch->access, 0);
+ bt_spinreadlock (set->access);
break;
case BtLockDelete:
- bt_writelock (page->latch->access, 0);
+ bt_spinwritelock (set->access);
break;
case BtLockParent:
- bt_writelock (page->latch->parent, 0);
+ bt_spinwritelock (set->parent);
break;
- default:
- return bt->err = BTERR_lock;
}
-
- if( pageptr )
- *pageptr = page;
- return bt->err = 0;
}
// remove write, read, or parent lock on requested page
-BTERR bt_unlockpage(BtDb *bt, uid page_no, BtLock mode)
+void bt_unlockpage(BtLock mode, BtLatchSet *set)
{
-uint subpage, idx;
-BtPool *pool;
-BtPage page;
-
- // since page is pinned
- // it should still be in the buffer pool
- // and is in no danger of being a victim for reuse
-
- idx = (uint)(page_no >> bt->mgr->seg_bits) % bt->mgr->hashsize;
- bt_readlock (&bt->mgr->latch[idx], 1);
-
- if( pool = bt_findpool(bt, page_no, idx) )
- subpage = (uint)(page_no & bt->mgr->poolmask);
- else
- return bt->err = BTERR_hash;
-
- bt_releaseread (&bt->mgr->latch[idx], 1);
- page = (BtPage)(pool->map + (subpage << bt->mgr->page_bits));
-
switch( mode ) {
case BtLockRead:
- bt_releaseread (page->latch->readwr, 0);
+ bt_spinreleaseread (set->readwr);
break;
case BtLockWrite:
- bt_releasewrite (page->latch->readwr, 0);
+ bt_spinreleasewrite (set->readwr);
break;
case BtLockAccess:
- bt_releaseread (page->latch->access, 0);
+ bt_spinreleaseread (set->access);
break;
case BtLockDelete:
- bt_releasewrite (page->latch->access, 0);
+ bt_spinreleasewrite (set->access);
break;
case BtLockParent:
- bt_releasewrite (page->latch->parent, 0);
+ bt_spinreleasewrite (set->parent);
break;
- default:
- return bt->err = BTERR_lock;
}
-
-#ifdef unix
- __sync_fetch_and_add(&pool->pin, -1);
-#else
- _InterlockedDecrement (&pool->pin);
-#endif
- return bt->err = 0;
-}
-
-// deallocate a deleted page
-// place on free chain out of allocator page
-
-BTERR bt_freepage(BtDb *bt, uid page_no)
-{
- // obtain delete lock on deleted page
-
- if( bt_lockpage(bt, page_no, BtLockDelete, NULL) )
- return bt->err;
-
- // obtain write lock on deleted page
-
- if( bt_lockpage(bt, page_no, BtLockWrite, &bt->temp) )
- return bt->err;
-
- // lock allocation page
-
- if ( bt_lockpage(bt, ALLOC_page, BtLockWrite, &bt->alloc) )
- return bt->err;
-
- // store chain in second right
- bt_putid(bt->temp->right, bt_getid(bt->alloc[1].right));
- bt_putid(bt->alloc[1].right, page_no);
-
- // unlock page zero
-
- if( bt_unlockpage(bt, ALLOC_page, BtLockWrite) )
- return bt->err;
-
- // remove write lock on deleted node
-
- if( bt_unlockpage(bt, page_no, BtLockWrite) )
- return bt->err;
-
- // remove delete lock on deleted node
-
- if( bt_unlockpage(bt, page_no, BtLockDelete) )
- return bt->err;
-
- return 0;
}
// allocate a new page and write page into it
uid bt_newpage(BtDb *bt, BtPage page)
{
+BtLatchSet *set;
+BtPool *pool;
uid new_page;
BtPage pmap;
-int subpage;
int reuse;
- // lock page zero
+ // lock allocation page
- if( bt_lockpage(bt, ALLOC_page, BtLockWrite, &bt->alloc) )
- return 0;
+ bt_spinwritelock(bt->mgr->latchmgr->lock);
// use empty chain first
// else allocate empty page
- if( new_page = bt_getid(bt->alloc[1].right) ) {
- if( bt_lockpage (bt, new_page, BtLockWrite, &bt->temp) )
- return 0;
- bt_putid(bt->alloc[1].right, bt_getid(bt->temp->right));
- if( bt_unlockpage (bt, new_page, BtLockWrite) )
+ if( new_page = bt_getid(bt->mgr->latchmgr->alloc[1].right) ) {
+ if( pool = bt_pinpool (bt, new_page) )
+ pmap = bt_page (bt, pool, new_page);
+ else
return 0;
+ bt_putid(bt->mgr->latchmgr->alloc[1].right, bt_getid(pmap->right));
+ bt_unpinpool (pool);
reuse = 1;
} else {
- new_page = bt_getid(bt->alloc->right);
- bt_putid(bt->alloc->right, new_page+1);
+ new_page = bt_getid(bt->mgr->latchmgr->alloc->right);
+ bt_putid(bt->mgr->latchmgr->alloc->right, new_page+1);
reuse = 0;
}
-
#ifdef unix
- // if writing first page of pool block
- // expand file thru last page in the block
-
- if( !reuse && (new_page & bt->mgr->poolmask) == 0 )
- if( pwrite(bt->mgr->idx, bt->zero, bt->mgr->page_size, (new_page | bt->mgr->poolmask) << bt->mgr->page_bits) < bt->mgr->page_size )
+ if ( pwrite(bt->mgr->idx, page, bt->mgr->page_size, new_page << bt->mgr->page_bits) < bt->mgr->page_size )
return bt->err = BTERR_wrt, 0;
-#endif
- // unlock page allocation page
- if( bt_unlockpage(bt, ALLOC_page, BtLockWrite) )
- return 0;
+ // if writing first page of pool block, zero last page in the block
+ if ( !reuse && bt->mgr->poolmask > 0 && (new_page & bt->mgr->poolmask) == 0 )
+ {
+ // use zero buffer to write zeros
+ memset(bt->zero, 0, bt->mgr->page_size);
+ if ( pwrite(bt->mgr->idx,bt->zero, bt->mgr->page_size, (new_page | bt->mgr->poolmask) << bt->mgr->page_bits) < bt->mgr->page_size )
+ return bt->err = BTERR_wrt, 0;
+ }
+#else
// bring new page into pool and copy page.
- // on Windows, this will extend the file into the new page.
+ // this will extend the file into the new pages.
- if( bt_lockpage(bt, new_page, BtLockWrite, &pmap) )
+ if( pool = bt_pinpool (bt, new_page) )
+ pmap = bt_page (bt, pool, new_page);
+ else
return 0;
- // copy source page but leave latch area intact
-
- memcpy((char *)pmap + sizeof(BtLatchSet), (char *)page + sizeof(BtLatchSet), bt->mgr->page_size - sizeof(BtLatchSet));
-
- if( bt_unlockpage (bt, new_page, BtLockWrite) )
- return 0;
+ memcpy(pmap, page, bt->mgr->page_size);
+ bt_unpinpool (pool);
+#endif
+ // unlock allocation latch and return new page no
+ bt_spinreleasewrite(bt->mgr->latchmgr->lock);
return new_page;
}
int bt_loadpage (BtDb *bt, unsigned char *key, uint len, uint lvl, uint lock)
{
uid page_no = ROOT_page, prevpage = 0;
+BtLatchSet *set, *prevset;
uint drill = 0xff, slot;
uint mode, prevmode;
+BtPool *prevpool;
// start at root of btree and drill down
+ bt->set = NULL;
+
do {
// determine lock mode of drill level
mode = (lock == BtLockWrite) && (drill == lvl) ? BtLockWrite : BtLockRead;
+ bt->set = bt_pinlatch (bt, page_no);
bt->page_no = page_no;
+ // pin page contents
+
+ if( bt->pool = bt_pinpool (bt, page_no) )
+ bt->page = bt_page (bt, bt->pool, page_no);
+ else
+ return 0;
+
// obtain access lock using lock chaining with Access mode
if( page_no > ROOT_page )
- if( bt_lockpage(bt, page_no, BtLockAccess, NULL) )
- return 0;
+ bt_lockpage(BtLockAccess, bt->set);
- if( prevpage )
- if( bt_unlockpage(bt, prevpage, prevmode) )
- return 0;
+ // release & unpin parent page
+
+ if( prevpage ) {
+ bt_unlockpage(prevmode, prevset);
+ bt_unpinlatch (prevset);
+ bt_unpinpool (prevpool);
+ prevpage = 0;
+ }
// obtain read lock using lock chaining
- // and pin page contents
- if( bt_lockpage(bt, page_no, mode, &bt->page) )
- return 0;
+ bt_lockpage(mode, bt->set);
if( page_no > ROOT_page )
- if( bt_unlockpage(bt, page_no, BtLockAccess) )
- return 0;
+ bt_unlockpage(BtLockAccess, bt->set);
// re-read and re-lock root after determining actual level of root
drill = bt->page->lvl;
- if( lock == BtLockWrite && drill == lvl )
- if( bt_unlockpage(bt, page_no, mode) )
- return 0;
- else
- continue;
+ if( lock == BtLockWrite && drill == lvl ) {
+ bt_unlockpage(mode, bt->set);
+ bt_unpinlatch (bt->set);
+ bt_unpinpool (bt->pool);
+ continue;
+ }
}
// find key on page at this level
slideright:
prevpage = bt->page_no;
+ prevpool = bt->pool;
+ prevset = bt->set;
prevmode = mode;
} while( page_no );
BTERR bt_deletekey (BtDb *bt, unsigned char *key, uint len, uint lvl)
{
unsigned char lowerkey[256], higherkey[256];
+BtLatchSet *rset, *set;
+BtPool *pool, *rpool;
uid page_no, right;
uint slot, tod;
+BtPage rpage;
BtKey ptr;
if( slot = bt_loadpage (bt, key, len, lvl, BtLockWrite) )
// if key is found delete it, otherwise ignore request
- if( !keycmp (ptr, key, len) )
- if( slotptr(bt->page, slot)->dead == 0 ) {
+ if( bt->found = !keycmp (ptr, key, len) )
+ if( bt->found = slotptr(bt->page, slot)->dead == 0 ) {
slotptr(bt->page,slot)->dead = 1;
if( slot < bt->page->cnt )
bt->page->dirty = 1;
right = bt_getid(bt->page->right);
page_no = bt->page_no;
+ pool = bt->pool;
+ set = bt->set;
- if( !right || bt->page->act )
- return bt_unlockpage(bt, page_no, BtLockWrite);
+ if( !right || bt->page->act ) {
+ bt_unlockpage(BtLockWrite, set);
+ bt_unpinlatch (set);
+ bt_unpinpool (pool);
+ return bt->err;
+ }
// obtain Parent lock over write lock
- if( bt_lockpage(bt, page_no, BtLockParent, NULL) )
- return bt->err;
+ bt_lockpage(BtLockParent, set);
// keep copy of key to delete
// lock and map right page
- if ( bt_lockpage(bt, right, BtLockWrite, &bt->temp) )
+ if( rpool = bt_pinpool (bt, right) )
+ rpage = bt_page (bt, rpool, right);
+ else
return bt->err;
+ rset = bt_pinlatch (bt, right);
+ bt_lockpage(BtLockWrite, rset);
+
// pull contents of next page into current empty page
- memcpy((char *)bt->page + sizeof(BtLatchSet), (char *)bt->temp + sizeof(BtLatchSet), bt->mgr->page_size - sizeof(BtLatchSet));
+
+ memcpy (bt->page, rpage, bt->mgr->page_size);
// keep copy of key to update
- ptr = keyptr(bt->temp, bt->temp->cnt);
+
+ ptr = keyptr(rpage, rpage->cnt);
memcpy(higherkey, ptr, ptr->len + 1);
// Mark right page as deleted and point it to left page
// until we can post updates at higher level.
- bt_putid(bt->temp->right, page_no);
- bt->temp->kill = 1;
- bt->temp->cnt = 0;
+ bt_putid(rpage->right, page_no);
+ rpage->kill = 1;
+ rpage->cnt = 0;
- if( bt_unlockpage(bt, right, BtLockWrite) )
- return bt->err;
- if( bt_unlockpage(bt, page_no, BtLockWrite) )
- return bt->err;
+ bt_unlockpage(BtLockWrite, rset);
+ bt_unlockpage(BtLockWrite, set);
// delete old lower key to consolidated node
if( bt_insertkey (bt, higherkey+1, *higherkey, lvl + 1, page_no, tod) )
return bt->err;
- // obtain write lock and
- // add right block to free chain
+ // add killed right block to free chain
+ // lock latch mgr
- if( bt_freepage (bt, right) )
- return bt->err;
+ bt_spinwritelock(bt->mgr->latchmgr->lock);
+
+ // store free chain in allocation page second right
+ bt_putid(rpage->right, bt_getid(bt->mgr->latchmgr->alloc[1].right));
+ bt_putid(bt->mgr->latchmgr->alloc[1].right, right);
+
+ // unlock latch mgr and unpin right page
+
+ bt_spinreleasewrite(bt->mgr->latchmgr->lock);
+ bt_unpinlatch (rset);
+ bt_unpinpool (rpool);
// remove ParentModify lock
- if( bt_unlockpage(bt, page_no, BtLockParent) )
- return bt->err;
-
+ bt_unlockpage(BtLockParent, set);
+ bt_unpinlatch (set);
+ bt_unpinpool (pool);
return 0;
}
else
id = 0;
- if ( bt_unlockpage(bt, bt->page_no, BtLockRead) )
- return 0;
-
+ bt_unlockpage (BtLockRead, bt->set);
+ bt_unpinlatch (bt->set);
+ bt_unpinpool (bt->pool);
return id;
}
// check page for space available,
// clean if necessary and return
-// 0 - page needs splitting
-// 1 - go ahead
+// =0 - page needs splitting
+// >0 - go ahead at returned slot
-uint bt_cleanpage(BtDb *bt, uint amt)
+uint bt_cleanpage(BtDb *bt, uint amt, uint slot)
{
uint nxt = bt->mgr->page_size;
BtPage page = bt->page;
uint cnt = 0, idx = 0;
uint max = page->cnt;
+uint newslot;
BtKey key;
- if( page->min >= (page->cnt+1) * sizeof(BtSlot) + sizeof(*page) + amt + 1 )
- return 1;
+ if( page->min >= (max+1) * sizeof(BtSlot) + sizeof(*page) + amt + 1 )
+ return slot;
// skip cleanup if nothing to reclaim
page->dirty = 0;
page->act = 0;
+ // always leave fence key in list
+
while( cnt++ < max ) {
- // always leave fence key in list
- if( cnt < max && slotptr(bt->frame,cnt)->dead )
+ if( cnt == slot )
+ newslot = idx + 1;
+ else if( cnt < max && slotptr(bt->frame,cnt)->dead )
continue;
// copy key
page->min = nxt;
page->cnt = idx;
- if( page->min >= (page->cnt+1) * sizeof(BtSlot) + sizeof(*page) + amt + 1 )
- return 1;
+ if( page->min >= (idx+1) * sizeof(BtSlot) + sizeof(*page) + amt + 1 )
+ return newslot;
return 0;
}
root->act = 2;
root->lvl++;
- // release root (bt->page)
+ // release and unpin root (bt->page)
- return bt_unlockpage(bt, bt->page_no, BtLockWrite);
+ bt_unlockpage(BtLockWrite, bt->set);
+ bt_unpinlatch (bt->set);
+ bt_unpinpool (bt->pool);
+ return 0;
}
// split already locked full node
uint cnt = 0, idx = 0, max, nxt = bt->mgr->page_size;
unsigned char oldkey[256], lowerkey[256];
uid page_no = bt->page_no, right;
+BtLatchSet *nset, *set = bt->set;
+BtPool *pool = bt->pool;
BtPage page = bt->page;
uint lvl = page->lvl;
uid new_page;
// obtain Parent/Write locks
// for left and right node pages
- if( bt_lockpage (bt, new_page, BtLockParent, NULL) )
- return bt->err;
+ nset = bt_pinlatch (bt, new_page);
- if( bt_lockpage (bt, page_no, BtLockParent, NULL) )
- return bt->err;
+ bt_lockpage (BtLockParent, nset);
+ bt_lockpage (BtLockParent, set);
// release wr lock on left page
+ // (keep the SMO in sequence)
- if( bt_unlockpage (bt, page_no, BtLockWrite) )
- return bt->err;
+ bt_unlockpage (BtLockWrite, set);
// insert new fence for reformulated left block
if( bt_insertkey (bt, oldkey+1, *oldkey, lvl + 1, new_page, tod) )
return bt->err;
- // release Parent & Write locks
-
- if( bt_unlockpage (bt, new_page, BtLockParent) )
- return bt->err;
-
- if( bt_unlockpage (bt, page_no, BtLockParent) )
- return bt->err;
+ // release Parent locks
+ bt_unlockpage (BtLockParent, nset);
+ bt_unlockpage (BtLockParent, set);
+ bt_unpinlatch (nset);
+ bt_unpinlatch (set);
+ bt_unpinpool (pool);
return 0;
}
// Insert new key into the btree at requested level.
-// Level zero pages are leaf pages and are unlocked at exit.
-// Interior pages remain locked.
+// Level zero pages are leaf pages. Page is unlocked at exit.
BTERR bt_insertkey (BtDb *bt, unsigned char *key, uint len, uint lvl, uid id, uint tod)
{
page = bt->page;
- if( !keycmp (ptr, key, len) ) {
+ if( bt->found = !keycmp (ptr, key, len) ) {
slotptr(page, slot)->dead = 0;
slotptr(page, slot)->tod = tod;
bt_putid(slotptr(page,slot)->id, id);
- return bt_unlockpage(bt, bt->page_no, BtLockWrite);
+ bt_unlockpage(BtLockWrite, bt->set);
+ bt_unpinlatch(bt->set);
+ bt_unpinpool (bt->pool);
+ return bt->err;
}
// check if page has enough space
- if( bt_cleanpage (bt, len) )
+ if( slot = bt_cleanpage (bt, len, slot) )
break;
if( bt_splitpage (bt) )
slotptr(page, slot)->tod = tod;
slotptr(page, slot)->dead = 0;
- return bt_unlockpage(bt, bt->page_no, BtLockWrite);
+ bt_unlockpage (BtLockWrite, bt->set);
+ bt_unpinlatch (bt->set);
+ bt_unpinpool (bt->pool);
+ return 0;
}
// cache page of keys into cursor and return starting slot for given key
if( slot = bt_loadpage (bt, key, len, 0, BtLockRead) )
memcpy (bt->cursor, bt->page, bt->mgr->page_size);
bt->cursor_page = bt->page_no;
- if ( bt_unlockpage(bt, bt->page_no, BtLockRead) )
- return 0;
-
+ bt_unlockpage(BtLockRead, bt->set);
+ bt_unpinlatch (bt->set);
+ bt_unpinpool (bt->pool);
return slot;
}
uint bt_nextkey (BtDb *bt, uint slot)
{
-off64_t right;
+BtPool *pool;
+BtPage page;
+uid right;
do {
right = bt_getid(bt->cursor->right);
bt->cursor_page = right;
- if( bt_lockpage(bt, right, BtLockRead, &bt->page) )
+ if( pool = bt_pinpool (bt, right) )
+ page = bt_page (bt, pool, right);
+ else
return 0;
- memcpy (bt->cursor, bt->page, bt->mgr->page_size);
+ bt->set = bt_pinlatch (bt, right);
+ bt_lockpage(BtLockRead, bt->set);
- if ( bt_unlockpage(bt, right, BtLockRead) )
- return 0;
+ memcpy (bt->cursor, page, bt->mgr->page_size);
+ bt_unlockpage(BtLockRead, bt->set);
+ bt_unpinlatch (bt->set);
+ bt_unpinpool (pool);
slot = 0;
} while( 1 );
return slotptr(bt->cursor,slot)->tod;
}
-
#ifdef STANDALONE
+void bt_latchaudit (BtDb *bt)
+{
+ushort idx, hashidx;
+BtLatchSet *set;
+BtPool *pool;
+BtPage page;
+uid page_no;
+
+#ifdef unix
+ for( idx = 1; idx < bt->mgr->latchmgr->latchdeployed; idx++ ) {
+ set = bt->mgr->latchsets + idx;
+ if( *(ushort *)set->readwr || *(ushort *)set->access || *(ushort *)set->parent ) {
+ fprintf(stderr, "latchset %d locked for page %6x\n", idx, set->page_no);
+ *(ushort *)set->readwr = 0;
+ *(ushort *)set->access = 0;
+ *(ushort *)set->parent = 0;
+ }
+ if( set->pin ) {
+ fprintf(stderr, "latchset %d pinned\n", idx);
+ set->pin = 0;
+ }
+ }
+
+ for( hashidx = 0; hashidx < bt->mgr->latchmgr->latchhash; hashidx++ ) {
+ if( *(uint *)bt->mgr->latchmgr->table[hashidx].latch )
+ fprintf(stderr, "latchmgr locked\n");
+ if( idx = bt->mgr->latchmgr->table[hashidx].slot ) do {
+ set = bt->mgr->latchsets + idx;
+ if( *(uint *)set->readwr || *(ushort *)set->access || *(ushort *)set->parent )
+ fprintf(stderr, "latchset %d locked\n", idx);
+ if( set->hash != hashidx )
+ fprintf(stderr, "latchset %d wrong hashidx\n", idx);
+ if( set->pin )
+ fprintf(stderr, "latchset %d pinned\n", idx);
+ } while( idx = set->next );
+ }
+ page_no = bt_getid(bt->mgr->latchmgr->alloc[1].right);
+
+ while( page_no ) {
+ fprintf(stderr, "free: %.6x\n", (uint)page_no);
+ pool = bt_pinpool (bt, page_no);
+ page = bt_page (bt, pool, page_no);
+ page_no = bt_getid(page->right);
+ bt_unpinpool (pool);
+ }
+#endif
+}
+
typedef struct {
char type, idx;
char *infile;
ThreadArg *args = arg;
int ch, len = 0, slot;
time_t tod[1];
+BtPool *pool;
BtPage page;
BtKey ptr;
BtDb *bt;
switch(args->type | 0x20)
{
+ case 'a':
+ fprintf(stderr, "started latch mgr audit\n");
+ bt_latchaudit (bt);
+ fprintf(stderr, "finished latch mgr audit\n");
+ break;
+
case 'w':
fprintf(stderr, "started indexing for %s\n", args->infile);
if( in = fopen (args->infile, "rb") )
if( args->num == 1 )
sprintf((char *)key+len, "%.9d", 1000000000 - line), len += 9;
+
else if( args->num )
- sprintf((char *)key+len, "%.9d", line+args->idx * args->num), len += 9;
+ sprintf((char *)key+len, "%.9d", line + args->idx * args->num), len += 9;
if( bt_insertkey (bt, key, len, 0, line, *tod) )
fprintf(stderr, "Error %d Line: %d\n", bt->err, line), exit(0);
line++;
if( args->num == 1 )
sprintf((char *)key+len, "%.9d", 1000000000 - line), len += 9;
+
else if( args->num )
- sprintf((char *)key+len, "%.9d", line+args->idx * args->num), len += 9;
+ sprintf((char *)key+len, "%.9d", line + args->idx * args->num), len += 9;
if( bt_deletekey (bt, key, len, 0) )
fprintf(stderr, "Error %d Line: %d\n", bt->err, line), exit(0);
line++;
if( args->num == 1 )
sprintf((char *)key+len, "%.9d", 1000000000 - line), len += 9;
+
else if( args->num )
- sprintf((char *)key+len, "%.9d", line+args->idx * args->num), len += 9;
+ sprintf((char *)key+len, "%.9d", line + args->idx * args->num), len += 9;
if( bt_findkey (bt, key, len) )
found++;
fprintf(stderr, "started reading\n");
do {
- bt_lockpage (bt, page_no, BtLockRead, &page);
+ if( bt->pool = bt_pinpool (bt, page_no) )
+ page = bt_page (bt, bt->pool, page_no);
+ else
+ break;
+ bt->set = bt_pinlatch (bt, page_no);
+ bt_lockpage (BtLockRead, bt->set);
cnt += page->act;
next = bt_getid (page->right);
- bt_unlockpage (bt, page_no, BtLockRead);
+ bt_unlockpage (BtLockRead, bt->set);
+ bt_unpinlatch (bt->set);
+ bt_unpinpool (bt->pool);
} while( page_no = next );
cnt--; // remove stopper key
fprintf (stderr, " where page_bits is the page size in bits\n");
fprintf (stderr, " mapped_segments is the number of mmap segments in buffer pool\n");
fprintf (stderr, " seg_bits is the size of individual segments in buffer pool in pages in bits\n");
- fprintf (stderr, " line_numbers set to 1 to append line numbers to input lines\n");
+ fprintf (stderr, " line_numbers = 1 to append line numbers to keys\n");
fprintf (stderr, " src_file1 thru src_filen are files of keys separated by newline\n");
exit(0);
}
poolsize = atoi(argv[4]);
if( !poolsize )
- fprintf (stderr, "Warning: mapped_pool has no segments\n");
+ fprintf (stderr, "Warning: no mapped_pool\n");
if( poolsize > 65535 )
fprintf (stderr, "Warning: mapped_pool > 65535 segments\n");
projects / btree / blobdiff