Fix small bug in main when there is less t han one input file

[btree] / threadskv8.c

diff --git a/threadskv8.c b/threadskv8.c
index 3f669b83d933d83d640cd3fe7079aacae2eb537f..9d17a4a6a99cccb611911c7e6fbb91b36d973e36 100644 (file)
--- a/threadskv8.c
+++ b/threadskv8.c
@@ -112,15 +112,6 @@ typedef struct {
        ushort serving[1];
 } RWLock;
 
-//     write only queue lock
-
-typedef struct {
-       ushort ticket[1];
-       ushort serving[1];
-       ushort tid;
-       ushort dup;
-} WOLock;
-
 #define PHID 0x1
 #define PRES 0x2
 #define MASK 0x3
@@ -143,6 +134,14 @@ volatile typedef struct {
 #define BOTH 3
 #define SHARE 4
 
+//     write only reentrant lock
+
+typedef struct {
+       BtSpinLatch xcl[1];
+       volatile ushort tid[1];
+       volatile ushort dup[1];
+} WOLock;
+
 //  hash table entries
 
 typedef struct {
@@ -411,41 +410,39 @@ uid bt_newdup (BtDb *bt)
 #endif
 }
 
-//     Write-Only Queue Lock
+void bt_spinreleasewrite(BtSpinLatch *latch);
+void bt_spinwritelock(BtSpinLatch *latch);
+
+//     Write-Only Reentrant Lock
 
 void WriteOLock (WOLock *lock, ushort tid)
 {
-ushort tix;
+  while( 1 ) {
+       bt_spinwritelock(lock->xcl);
 
-       if( lock->tid == tid ) {
-               lock->dup++;
+       if( *lock->tid == tid ) {
+               *lock->dup += 1;
+               bt_spinreleasewrite(lock->xcl);
                return;
        }
-#ifdef unix
-       tix = __sync_fetch_and_add (lock->ticket, 1);
-#else
-       tix = _InterlockedExchangeAdd16 (lock->ticket, 1);
-#endif
-       // wait for our ticket to come up
-
-       while( tix != lock->serving[0] )
-#ifdef unix
-               sched_yield();
-#else
-               SwitchToThread ();
-#endif
-       lock->tid = tid;
+       if( !*lock->tid ) {
+               *lock->tid = tid;
+               bt_spinreleasewrite(lock->xcl);
+               return;
+       }
+       bt_spinreleasewrite(lock->xcl);
+       sched_yield();
+  }
 }
 
 void WriteORelease (WOLock *lock)
 {
-       if( lock->dup ) {
-               lock->dup--;
+       if( *lock->dup ) {
+               *lock->dup -= 1;
                return;
        }
 
-       lock->tid = 0;
-       lock->serving[0]++;
+       *lock->tid = 0;
 }
 
 //     Phase-Fair reader/writer lock implementation
@@ -3054,7 +3051,7 @@ uint slot = 0;
                        fprintf(stderr, "latchset %d accesslocked for page %.8x\n", slot, latch->page_no);
                memset ((ushort *)latch->access, 0, sizeof(RWLock));
 
-               if( *latch->parent->ticket != *latch->parent->serving )
+               if( *latch->parent->tid )
                        fprintf(stderr, "latchset %d parentlocked for page %.8x\n", slot, latch->page_no);
                memset ((ushort *)latch->parent, 0, sizeof(RWLock));
 
@@ -3087,9 +3084,9 @@ BtKey *ptr;
                        fprintf(stderr, "latchset %d accesslocked for page %.8x\n", idx, latch->page_no);
                memset ((ushort *)latch->access, 0, sizeof(RWLock));
 
-               if( *latch->parent->ticket != *latch->parent->serving )
+               if( *latch->parent->tid )
                        fprintf(stderr, "latchset %d parentlocked for page %.8x\n", idx, latch->page_no);
-               memset ((ushort *)latch->parent, 0, sizeof(RWLock));
+               memset ((ushort *)latch->parent, 0, sizeof(WOLock));
 
                if( latch->pin ) {
                        fprintf(stderr, "latchset %d pinned for page %.8x\n", idx, latch->page_no);