diff options
Diffstat (limited to 'gcc-4.8.1/libgo/runtime/mheap.c')
| -rw-r--r-- | gcc-4.8.1/libgo/runtime/mheap.c | 504 |
1 files changed, 0 insertions, 504 deletions
diff --git a/gcc-4.8.1/libgo/runtime/mheap.c b/gcc-4.8.1/libgo/runtime/mheap.c deleted file mode 100644 index 6636b015d..000000000 --- a/gcc-4.8.1/libgo/runtime/mheap.c +++ /dev/null @@ -1,504 +0,0 @@ -// 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. - -// Page heap. -// -// See malloc.h for overview. -// -// When a MSpan is in the heap free list, state == MSpanFree -// and heapmap(s->start) == span, heapmap(s->start+s->npages-1) == span. -// -// When a MSpan is allocated, state == MSpanInUse -// and heapmap(i) == span for all s->start <= i < s->start+s->npages. - -#include "runtime.h" -#include "arch.h" -#include "malloc.h" - -static MSpan *MHeap_AllocLocked(MHeap*, uintptr, int32); -static bool MHeap_Grow(MHeap*, uintptr); -static void MHeap_FreeLocked(MHeap*, MSpan*); -static MSpan *MHeap_AllocLarge(MHeap*, uintptr); -static MSpan *BestFit(MSpan*, uintptr, MSpan*); - -static void -RecordSpan(void *vh, byte *p) -{ - MHeap *h; - MSpan *s; - MSpan **all; - uint32 cap; - - h = vh; - s = (MSpan*)p; - if(h->nspan >= h->nspancap) { - cap = 64*1024/sizeof(all[0]); - if(cap < h->nspancap*3/2) - cap = h->nspancap*3/2; - all = (MSpan**)runtime_SysAlloc(cap*sizeof(all[0])); - if(h->allspans) { - runtime_memmove(all, h->allspans, h->nspancap*sizeof(all[0])); - runtime_SysFree(h->allspans, h->nspancap*sizeof(all[0])); - } - h->allspans = all; - h->nspancap = cap; - } - h->allspans[h->nspan++] = s; -} - -// Initialize the heap; fetch memory using alloc. -void -runtime_MHeap_Init(MHeap *h, void *(*alloc)(uintptr)) -{ - uint32 i; - - runtime_FixAlloc_Init(&h->spanalloc, sizeof(MSpan), alloc, RecordSpan, h); - runtime_FixAlloc_Init(&h->cachealloc, sizeof(MCache), alloc, nil, nil); - // h->mapcache needs no init - for(i=0; i<nelem(h->free); i++) - runtime_MSpanList_Init(&h->free[i]); - runtime_MSpanList_Init(&h->large); - for(i=0; i<nelem(h->central); i++) - runtime_MCentral_Init(&h->central[i], i); -} - -// Allocate a new span of npage pages from the heap -// and record its size class in the HeapMap and HeapMapCache. -MSpan* -runtime_MHeap_Alloc(MHeap *h, uintptr npage, int32 sizeclass, int32 acct, int32 zeroed) -{ - MSpan *s; - - runtime_lock(h); - runtime_purgecachedstats(runtime_m()->mcache); - s = MHeap_AllocLocked(h, npage, sizeclass); - if(s != nil) { - mstats.heap_inuse += npage<<PageShift; - if(acct) { - mstats.heap_objects++; - mstats.heap_alloc += npage<<PageShift; - } - } - runtime_unlock(h); - if(s != nil && *(uintptr*)(s->start<<PageShift) != 0 && zeroed) - runtime_memclr((byte*)(s->start<<PageShift), s->npages<<PageShift); - return s; -} - -static MSpan* -MHeap_AllocLocked(MHeap *h, uintptr npage, int32 sizeclass) -{ - uintptr n; - MSpan *s, *t; - PageID p; - - // Try in fixed-size lists up to max. - for(n=npage; n < nelem(h->free); n++) { - if(!runtime_MSpanList_IsEmpty(&h->free[n])) { - s = h->free[n].next; - goto HaveSpan; - } - } - - // Best fit in list of large spans. - if((s = MHeap_AllocLarge(h, npage)) == nil) { - if(!MHeap_Grow(h, npage)) - return nil; - if((s = MHeap_AllocLarge(h, npage)) == nil) - return nil; - } - -HaveSpan: - // Mark span in use. - if(s->state != MSpanFree) - runtime_throw("MHeap_AllocLocked - MSpan not free"); - if(s->npages < npage) - runtime_throw("MHeap_AllocLocked - bad npages"); - runtime_MSpanList_Remove(s); - s->state = MSpanInUse; - mstats.heap_idle -= s->npages<<PageShift; - mstats.heap_released -= s->npreleased<<PageShift; - s->npreleased = 0; - - if(s->npages > npage) { - // Trim extra and put it back in the heap. - t = runtime_FixAlloc_Alloc(&h->spanalloc); - mstats.mspan_inuse = h->spanalloc.inuse; - mstats.mspan_sys = h->spanalloc.sys; - runtime_MSpan_Init(t, s->start + npage, s->npages - npage); - s->npages = npage; - p = t->start; - if(sizeof(void*) == 8) - p -= ((uintptr)h->arena_start>>PageShift); - if(p > 0) - h->map[p-1] = s; - h->map[p] = t; - h->map[p+t->npages-1] = t; - *(uintptr*)(t->start<<PageShift) = *(uintptr*)(s->start<<PageShift); // copy "needs zeroing" mark - t->state = MSpanInUse; - MHeap_FreeLocked(h, t); - t->unusedsince = s->unusedsince; // preserve age - } - s->unusedsince = 0; - - // Record span info, because gc needs to be - // able to map interior pointer to containing span. - s->sizeclass = sizeclass; - s->elemsize = (sizeclass==0 ? s->npages<<PageShift : (uintptr)runtime_class_to_size[sizeclass]); - s->types.compression = MTypes_Empty; - p = s->start; - if(sizeof(void*) == 8) - p -= ((uintptr)h->arena_start>>PageShift); - for(n=0; n<npage; n++) - h->map[p+n] = s; - return s; -} - -// Allocate a span of exactly npage pages from the list of large spans. -static MSpan* -MHeap_AllocLarge(MHeap *h, uintptr npage) -{ - return BestFit(&h->large, npage, nil); -} - -// Search list for smallest span with >= npage pages. -// If there are multiple smallest spans, take the one -// with the earliest starting address. -static MSpan* -BestFit(MSpan *list, uintptr npage, MSpan *best) -{ - MSpan *s; - - for(s=list->next; s != list; s=s->next) { - if(s->npages < npage) - continue; - if(best == nil - || s->npages < best->npages - || (s->npages == best->npages && s->start < best->start)) - best = s; - } - return best; -} - -// Try to add at least npage pages of memory to the heap, -// returning whether it worked. -static bool -MHeap_Grow(MHeap *h, uintptr npage) -{ - uintptr ask; - void *v; - MSpan *s; - PageID p; - - // Ask for a big chunk, to reduce the number of mappings - // the operating system needs to track; also amortizes - // the overhead of an operating system mapping. - // Allocate a multiple of 64kB (16 pages). - npage = (npage+15)&~15; - ask = npage<<PageShift; - if(ask < HeapAllocChunk) - ask = HeapAllocChunk; - - v = runtime_MHeap_SysAlloc(h, ask); - if(v == nil) { - if(ask > (npage<<PageShift)) { - ask = npage<<PageShift; - v = runtime_MHeap_SysAlloc(h, ask); - } - if(v == nil) { - runtime_printf("runtime: out of memory: cannot allocate %D-byte block (%D in use)\n", (uint64)ask, mstats.heap_sys); - return false; - } - } - mstats.heap_sys += ask; - - // Create a fake "in use" span and free it, so that the - // right coalescing happens. - s = runtime_FixAlloc_Alloc(&h->spanalloc); - mstats.mspan_inuse = h->spanalloc.inuse; - mstats.mspan_sys = h->spanalloc.sys; - runtime_MSpan_Init(s, (uintptr)v>>PageShift, ask>>PageShift); - p = s->start; - if(sizeof(void*) == 8) - p -= ((uintptr)h->arena_start>>PageShift); - h->map[p] = s; - h->map[p + s->npages - 1] = s; - s->state = MSpanInUse; - MHeap_FreeLocked(h, s); - return true; -} - -// Look up the span at the given address. -// Address is guaranteed to be in map -// and is guaranteed to be start or end of span. -MSpan* -runtime_MHeap_Lookup(MHeap *h, void *v) -{ - uintptr p; - - p = (uintptr)v; - if(sizeof(void*) == 8) - p -= (uintptr)h->arena_start; - return h->map[p >> PageShift]; -} - -// Look up the span at the given address. -// Address is *not* guaranteed to be in map -// and may be anywhere in the span. -// Map entries for the middle of a span are only -// valid for allocated spans. Free spans may have -// other garbage in their middles, so we have to -// check for that. -MSpan* -runtime_MHeap_LookupMaybe(MHeap *h, void *v) -{ - MSpan *s; - PageID p, q; - - if((byte*)v < h->arena_start || (byte*)v >= h->arena_used) - return nil; - p = (uintptr)v>>PageShift; - q = p; - if(sizeof(void*) == 8) - q -= (uintptr)h->arena_start >> PageShift; - s = h->map[q]; - if(s == nil || p < s->start || p - s->start >= s->npages) - return nil; - if(s->state != MSpanInUse) - return nil; - return s; -} - -// Free the span back into the heap. -void -runtime_MHeap_Free(MHeap *h, MSpan *s, int32 acct) -{ - runtime_lock(h); - runtime_purgecachedstats(runtime_m()->mcache); - mstats.heap_inuse -= s->npages<<PageShift; - if(acct) { - mstats.heap_alloc -= s->npages<<PageShift; - mstats.heap_objects--; - } - MHeap_FreeLocked(h, s); - runtime_unlock(h); -} - -static void -MHeap_FreeLocked(MHeap *h, MSpan *s) -{ - uintptr *sp, *tp; - MSpan *t; - PageID p; - - if(s->types.sysalloc) - runtime_settype_sysfree(s); - s->types.compression = MTypes_Empty; - - if(s->state != MSpanInUse || s->ref != 0) { - runtime_printf("MHeap_FreeLocked - span %p ptr %p state %d ref %d\n", s, s->start<<PageShift, s->state, s->ref); - runtime_throw("MHeap_FreeLocked - invalid free"); - } - mstats.heap_idle += s->npages<<PageShift; - s->state = MSpanFree; - runtime_MSpanList_Remove(s); - sp = (uintptr*)(s->start<<PageShift); - // Stamp newly unused spans. The scavenger will use that - // info to potentially give back some pages to the OS. - s->unusedsince = runtime_nanotime(); - s->npreleased = 0; - - // Coalesce with earlier, later spans. - p = s->start; - if(sizeof(void*) == 8) - p -= (uintptr)h->arena_start >> PageShift; - if(p > 0 && (t = h->map[p-1]) != nil && t->state != MSpanInUse) { - tp = (uintptr*)(t->start<<PageShift); - *tp |= *sp; // propagate "needs zeroing" mark - s->start = t->start; - s->npages += t->npages; - s->npreleased = t->npreleased; // absorb released pages - p -= t->npages; - h->map[p] = s; - runtime_MSpanList_Remove(t); - t->state = MSpanDead; - runtime_FixAlloc_Free(&h->spanalloc, t); - mstats.mspan_inuse = h->spanalloc.inuse; - mstats.mspan_sys = h->spanalloc.sys; - } - if(p+s->npages < nelem(h->map) && (t = h->map[p+s->npages]) != nil && t->state != MSpanInUse) { - tp = (uintptr*)(t->start<<PageShift); - *sp |= *tp; // propagate "needs zeroing" mark - s->npages += t->npages; - s->npreleased += t->npreleased; - h->map[p + s->npages - 1] = s; - runtime_MSpanList_Remove(t); - t->state = MSpanDead; - runtime_FixAlloc_Free(&h->spanalloc, t); - mstats.mspan_inuse = h->spanalloc.inuse; - mstats.mspan_sys = h->spanalloc.sys; - } - - // Insert s into appropriate list. - if(s->npages < nelem(h->free)) - runtime_MSpanList_Insert(&h->free[s->npages], s); - else - runtime_MSpanList_Insert(&h->large, s); -} - -static void -forcegchelper(void *vnote) -{ - Note *note = (Note*)vnote; - - runtime_gc(1); - runtime_notewakeup(note); -} - -// Release (part of) unused memory to OS. -// Goroutine created at startup. -// Loop forever. -void -runtime_MHeap_Scavenger(void* dummy) -{ - MHeap *h; - MSpan *s, *list; - uint64 tick, now, forcegc, limit; - uint32 k, i; - uintptr released, sumreleased; - const byte *env; - bool trace; - Note note, *notep; - - USED(dummy); - - // If we go two minutes without a garbage collection, force one to run. - forcegc = 2*60*1e9; - // If a span goes unused for 5 minutes after a garbage collection, - // we hand it back to the operating system. - limit = 5*60*1e9; - // Make wake-up period small enough for the sampling to be correct. - if(forcegc < limit) - tick = forcegc/2; - else - tick = limit/2; - - trace = false; - env = runtime_getenv("GOGCTRACE"); - if(env != nil) - trace = runtime_atoi(env) > 0; - - h = &runtime_mheap; - for(k=0;; k++) { - runtime_noteclear(¬e); - runtime_entersyscall(); - runtime_notetsleep(¬e, tick); - runtime_exitsyscall(); - - runtime_lock(h); - now = runtime_nanotime(); - if(now - mstats.last_gc > forcegc) { - runtime_unlock(h); - // The scavenger can not block other goroutines, - // otherwise deadlock detector can fire spuriously. - // GC blocks other goroutines via the runtime_worldsema. - runtime_noteclear(¬e); - notep = ¬e; - __go_go(forcegchelper, (void*)notep); - runtime_entersyscall(); - runtime_notesleep(¬e); - runtime_exitsyscall(); - if(trace) - runtime_printf("scvg%d: GC forced\n", k); - runtime_lock(h); - now = runtime_nanotime(); - } - sumreleased = 0; - for(i=0; i < nelem(h->free)+1; i++) { - if(i < nelem(h->free)) - list = &h->free[i]; - else - list = &h->large; - if(runtime_MSpanList_IsEmpty(list)) - continue; - for(s=list->next; s != list; s=s->next) { - if((now - s->unusedsince) > limit) { - released = (s->npages - s->npreleased) << PageShift; - mstats.heap_released += released; - sumreleased += released; - s->npreleased = s->npages; - runtime_SysUnused((void*)(s->start << PageShift), s->npages << PageShift); - } - } - } - runtime_unlock(h); - - if(trace) { - if(sumreleased > 0) - runtime_printf("scvg%d: %p MB released\n", k, sumreleased>>20); - runtime_printf("scvg%d: inuse: %D, idle: %D, sys: %D, released: %D, consumed: %D (MB)\n", - k, mstats.heap_inuse>>20, mstats.heap_idle>>20, mstats.heap_sys>>20, - mstats.heap_released>>20, (mstats.heap_sys - mstats.heap_released)>>20); - } - } -} - -// Initialize a new span with the given start and npages. -void -runtime_MSpan_Init(MSpan *span, PageID start, uintptr npages) -{ - span->next = nil; - span->prev = nil; - span->start = start; - span->npages = npages; - span->freelist = nil; - span->ref = 0; - span->sizeclass = 0; - span->elemsize = 0; - span->state = 0; - span->unusedsince = 0; - span->npreleased = 0; - span->types.compression = MTypes_Empty; -} - -// Initialize an empty doubly-linked list. -void -runtime_MSpanList_Init(MSpan *list) -{ - list->state = MSpanListHead; - list->next = list; - list->prev = list; -} - -void -runtime_MSpanList_Remove(MSpan *span) -{ - if(span->prev == nil && span->next == nil) - return; - span->prev->next = span->next; - span->next->prev = span->prev; - span->prev = nil; - span->next = nil; -} - -bool -runtime_MSpanList_IsEmpty(MSpan *list) -{ - return list->next == list; -} - -void -runtime_MSpanList_Insert(MSpan *list, MSpan *span) -{ - if(span->next != nil || span->prev != nil) { - runtime_printf("failed MSpanList_Insert %p %p %p\n", span, span->next, span->prev); - runtime_throw("MSpanList_Insert"); - } - span->next = list->next; - span->prev = list; - span->next->prev = span; - span->prev->next = span; -} - - |