| // Copyright 2009 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. |
| |
| // Per-P malloc cache for small objects. |
| // |
| // See malloc.h for an overview. |
| |
| #include "runtime.h" |
| #include "arch_GOARCH.h" |
| #include "malloc.h" |
| |
| void |
| runtime·MCache_Refill(MCache *c, int32 sizeclass) |
| { |
| MCacheList *l; |
| |
| // Replenish using central lists. |
| l = &c->list[sizeclass]; |
| if(l->list) |
| runtime·throw("MCache_Refill: the list is not empty"); |
| l->nlist = runtime·MCentral_AllocList(&runtime·mheap.central[sizeclass], &l->list); |
| if(l->list == nil) |
| runtime·throw("out of memory"); |
| } |
| |
| // Take n elements off l and return them to the central free list. |
| static void |
| ReleaseN(MCacheList *l, int32 n, int32 sizeclass) |
| { |
| MLink *first, **lp; |
| int32 i; |
| |
| // Cut off first n elements. |
| first = l->list; |
| lp = &l->list; |
| for(i=0; i<n; i++) |
| lp = &(*lp)->next; |
| l->list = *lp; |
| *lp = nil; |
| l->nlist -= n; |
| |
| // Return them to central free list. |
| runtime·MCentral_FreeList(&runtime·mheap.central[sizeclass], first); |
| } |
| |
| void |
| runtime·MCache_Free(MCache *c, void *v, int32 sizeclass, uintptr size) |
| { |
| MCacheList *l; |
| MLink *p; |
| |
| // Put back on list. |
| l = &c->list[sizeclass]; |
| p = v; |
| p->next = l->list; |
| l->list = p; |
| l->nlist++; |
| c->local_cachealloc -= size; |
| |
| // We transfer span at a time from MCentral to MCache, |
| // if we have 2 times more than that, release a half back. |
| if(l->nlist >= 2*(runtime·class_to_allocnpages[sizeclass]<<PageShift)/size) |
| ReleaseN(l, l->nlist/2, sizeclass); |
| } |
| |
| void |
| runtime·MCache_ReleaseAll(MCache *c) |
| { |
| int32 i; |
| MCacheList *l; |
| |
| for(i=0; i<NumSizeClasses; i++) { |
| l = &c->list[i]; |
| if(l->list) { |
| runtime·MCentral_FreeList(&runtime·mheap.central[i], l->list); |
| l->list = nil; |
| l->nlist = 0; |
| } |
| } |
| } |