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5d637b83a9
Count only number of frees, everything else is derivable and does not need to be counted on every malloc. benchmark old ns/op new ns/op delta BenchmarkMalloc8 68 66 -3.07% BenchmarkMalloc16 75 70 -6.48% BenchmarkMallocTypeInfo8 102 97 -4.80% BenchmarkMallocTypeInfo16 108 105 -2.78% R=golang-dev, dave, rsc CC=golang-dev https://golang.org/cl/9776043
82 lines
1.8 KiB
C
82 lines
1.8 KiB
C
// Copyright 2009 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// Per-P malloc cache for small objects.
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//
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// See malloc.h for an overview.
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#include "runtime.h"
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#include "arch_GOARCH.h"
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#include "malloc.h"
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void
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runtime·MCache_Refill(MCache *c, int32 sizeclass)
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{
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MCacheList *l;
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// Replenish using central lists.
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l = &c->list[sizeclass];
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if(l->list)
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runtime·throw("MCache_Refill: the list is not empty");
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l->nlist = runtime·MCentral_AllocList(&runtime·mheap.central[sizeclass], &l->list);
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if(l->list == nil)
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runtime·throw("out of memory");
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}
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// Take n elements off l and return them to the central free list.
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static void
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ReleaseN(MCacheList *l, int32 n, int32 sizeclass)
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{
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MLink *first, **lp;
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int32 i;
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// Cut off first n elements.
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first = l->list;
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lp = &l->list;
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for(i=0; i<n; i++)
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lp = &(*lp)->next;
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l->list = *lp;
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*lp = nil;
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l->nlist -= n;
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// Return them to central free list.
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runtime·MCentral_FreeList(&runtime·mheap.central[sizeclass], first);
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}
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void
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runtime·MCache_Free(MCache *c, void *v, int32 sizeclass, uintptr size)
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{
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MCacheList *l;
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MLink *p;
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// Put back on list.
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l = &c->list[sizeclass];
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p = v;
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p->next = l->list;
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l->list = p;
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l->nlist++;
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c->local_cachealloc -= size;
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// We transfer span at a time from MCentral to MCache,
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// if we have 2 times more than that, release a half back.
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if(l->nlist >= 2*(runtime·class_to_allocnpages[sizeclass]<<PageShift)/size)
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ReleaseN(l, l->nlist/2, sizeclass);
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}
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void
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runtime·MCache_ReleaseAll(MCache *c)
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{
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int32 i;
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MCacheList *l;
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for(i=0; i<NumSizeClasses; i++) {
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l = &c->list[i];
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if(l->list) {
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runtime·MCentral_FreeList(&runtime·mheap.central[i], l->list);
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l->list = nil;
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l->nlist = 0;
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}
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}
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}
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