diff options
Diffstat (limited to 'src/pkg/runtime/lfstack.goc')
-rw-r--r-- | src/pkg/runtime/lfstack.goc | 81 |
1 files changed, 0 insertions, 81 deletions
diff --git a/src/pkg/runtime/lfstack.goc b/src/pkg/runtime/lfstack.goc deleted file mode 100644 index f7b8effa0..000000000 --- a/src/pkg/runtime/lfstack.goc +++ /dev/null @@ -1,81 +0,0 @@ -// Copyright 2012 The Go Authors. All rights reserved. -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -// Lock-free stack. - -package runtime -#include "runtime.h" -#include "arch_GOARCH.h" - -#ifdef _64BIT -// Amd64 uses 48-bit virtual addresses, 47-th bit is used as kernel/user flag. -// So we use 17msb of pointers as ABA counter. -# define PTR_BITS 47 -#else -# define PTR_BITS 32 -#endif -#define PTR_MASK ((1ull<<PTR_BITS)-1) -#define CNT_MASK (0ull-1) - -#ifdef _64BIT -#ifdef GOOS_solaris -// SPARC64 and Solaris on AMD64 uses all 64 bits of virtual addresses. -// Use low-order three bits as ABA counter. -// http://docs.oracle.com/cd/E19120-01/open.solaris/816-5138/6mba6ua5p/index.html -#undef PTR_BITS -#undef CNT_MASK -#undef PTR_MASK -#define PTR_BITS 0 -#define CNT_MASK 7 -#define PTR_MASK ((0ull-1)<<3) -#endif -#endif - -void -runtime·lfstackpush(uint64 *head, LFNode *node) -{ - uint64 old, new; - - if((uintptr)node != ((uintptr)node&PTR_MASK)) { - runtime·printf("p=%p\n", node); - runtime·throw("runtime·lfstackpush: invalid pointer"); - } - - node->pushcnt++; - new = (uint64)(uintptr)node|(((uint64)node->pushcnt&CNT_MASK)<<PTR_BITS); - for(;;) { - old = runtime·atomicload64(head); - node->next = (LFNode*)(uintptr)(old&PTR_MASK); - if(runtime·cas64(head, old, new)) - break; - } -} - -LFNode* -runtime·lfstackpop(uint64 *head) -{ - LFNode *node, *node2; - uint64 old, new; - - for(;;) { - old = runtime·atomicload64(head); - if(old == 0) - return nil; - node = (LFNode*)(uintptr)(old&PTR_MASK); - node2 = runtime·atomicloadp(&node->next); - new = 0; - if(node2 != nil) - new = (uint64)(uintptr)node2|(((uint64)node2->pushcnt&CNT_MASK)<<PTR_BITS); - if(runtime·cas64(head, old, new)) - return node; - } -} - -func lfstackpush_go(head *uint64, node *LFNode) { - runtime·lfstackpush(head, node); -} - -func lfstackpop_go(head *uint64) (node *LFNode) { - node = runtime·lfstackpop(head); -} |