X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=rts%2Fsm%2FGCUtils.c;h=39a79f6b9f7439bbe0a39da39e941d38ea300ea3;hb=f6013eedb4dea47afac8167dfa08561ae90454db;hp=61b72b6c0af8baea35bbbebb8cb1909257908342;hpb=64c17c4561cf419a4c70511bafc0815ea670bb2e;p=ghc-hetmet.git diff --git a/rts/sm/GCUtils.c b/rts/sm/GCUtils.c index 61b72b6..39a79f6 100644 --- a/rts/sm/GCUtils.c +++ b/rts/sm/GCUtils.c @@ -1,6 +1,6 @@ /* ----------------------------------------------------------------------------- * - * (c) The GHC Team 1998-2006 + * (c) The GHC Team 1998-2008 * * Generational garbage collector: utilities * @@ -11,74 +11,301 @@ * * ---------------------------------------------------------------------------*/ +#include "PosixSource.h" #include "Rts.h" + +#include "BlockAlloc.h" #include "Storage.h" #include "GC.h" +#include "GCThread.h" #include "GCUtils.h" +#include "Printer.h" +#include "Trace.h" +#ifdef THREADED_RTS +#include "WSDeque.h" +#endif + +#ifdef THREADED_RTS +SpinLock gc_alloc_block_sync; +#endif + +bdescr * +allocBlock_sync(void) +{ + bdescr *bd; + ACQUIRE_SPIN_LOCK(&gc_alloc_block_sync); + bd = allocBlock(); + RELEASE_SPIN_LOCK(&gc_alloc_block_sync); + return bd; +} + +static bdescr * +allocGroup_sync(nat n) +{ + bdescr *bd; + ACQUIRE_SPIN_LOCK(&gc_alloc_block_sync); + bd = allocGroup(n); + RELEASE_SPIN_LOCK(&gc_alloc_block_sync); + return bd; +} + + +#if 0 +static void +allocBlocks_sync(nat n, bdescr **hd, bdescr **tl, + nat gen_no, step *stp, + StgWord32 flags) +{ + bdescr *bd; + nat i; + ACQUIRE_SPIN_LOCK(&gc_alloc_block_sync); + bd = allocGroup(n); + for (i = 0; i < n; i++) { + bd[i].blocks = 1; + bd[i].gen_no = gen_no; + bd[i].step = stp; + bd[i].flags = flags; + bd[i].link = &bd[i+1]; + bd[i].u.scan = bd[i].free = bd[i].start; + } + *hd = bd; + *tl = &bd[n-1]; + RELEASE_SPIN_LOCK(&gc_alloc_block_sync); +} +#endif + +void +freeChain_sync(bdescr *bd) +{ + ACQUIRE_SPIN_LOCK(&gc_alloc_block_sync); + freeChain(bd); + RELEASE_SPIN_LOCK(&gc_alloc_block_sync); +} /* ----------------------------------------------------------------------------- - Allocate a new to-space block in the given step. + Workspace utilities -------------------------------------------------------------------------- */ bdescr * -gc_alloc_block(step *stp) +grab_local_todo_block (step_workspace *ws) { - bdescr *bd = allocBlock(); - bd->gen_no = stp->gen_no; - bd->step = stp; - bd->link = NULL; + bdescr *bd; + step *stp; + + stp = ws->step; - // blocks in to-space in generations up to and including N - // get the BF_EVACUATED flag. - if (stp->gen_no <= N) { - bd->flags = BF_EVACUATED; - } else { - bd->flags = 0; + bd = ws->todo_overflow; + if (bd != NULL) + { + ws->todo_overflow = bd->link; + bd->link = NULL; + ws->n_todo_overflow--; + return bd; } - // Start a new to-space block, chain it on after the previous one. - if (stp->hp_bd != NULL) { - stp->hp_bd->free = stp->hp; - stp->hp_bd->link = bd; + bd = popWSDeque(ws->todo_q); + if (bd != NULL) + { + ASSERT(bd->link == NULL); + return bd; } - stp->hp_bd = bd; - stp->hp = bd->start; - stp->hpLim = stp->hp + BLOCK_SIZE_W; + return NULL; +} - stp->n_blocks++; - new_blocks++; +#if defined(THREADED_RTS) +bdescr * +steal_todo_block (nat s) +{ + nat n; + bdescr *bd; - return bd; + // look for work to steal + for (n = 0; n < n_gc_threads; n++) { + if (n == gct->thread_index) continue; + bd = stealWSDeque(gc_threads[n]->steps[s].todo_q); + if (bd) { + return bd; + } + } + return NULL; } +#endif -bdescr * -gc_alloc_scavd_block(step *stp) +void +push_scanned_block (bdescr *bd, step_workspace *ws) +{ + ASSERT(bd != NULL); + ASSERT(bd->link == NULL); + ASSERT(bd->step == ws->step); + ASSERT(bd->u.scan == bd->free); + + if (bd->start + bd->blocks * BLOCK_SIZE_W - bd->free > WORK_UNIT_WORDS) + { + // a partially full block: put it on the part_list list. + bd->link = ws->part_list; + ws->part_list = bd; + ws->n_part_blocks += bd->blocks; + IF_DEBUG(sanity, + ASSERT(countBlocks(ws->part_list) == ws->n_part_blocks)); + } + else + { + // put the scan block on the ws->scavd_list. + bd->link = ws->scavd_list; + ws->scavd_list = bd; + ws->n_scavd_blocks += bd->blocks; + IF_DEBUG(sanity, + ASSERT(countBlocks(ws->scavd_list) == ws->n_scavd_blocks)); + } +} + +StgPtr +todo_block_full (nat size, step_workspace *ws) { - bdescr *bd = allocBlock(); - bd->gen_no = stp->gen_no; - bd->step = stp; - - // blocks in to-space in generations up to and including N - // get the BF_EVACUATED flag. - if (stp->gen_no <= N) { - bd->flags = BF_EVACUATED; - } else { - bd->flags = 0; + StgPtr p; + bdescr *bd; + + // todo_free has been pre-incremented by Evac.c:alloc_for_copy(). We + // are expected to leave it bumped when we've finished here. + ws->todo_free -= size; + + bd = ws->todo_bd; + + ASSERT(bd != NULL); + ASSERT(bd->link == NULL); + ASSERT(bd->step == ws->step); + + // If the global list is not empty, or there's not much work in + // this block to push, and there's enough room in + // this block to evacuate the current object, then just increase + // the limit. + if (!looksEmptyWSDeque(ws->todo_q) || + (ws->todo_free - bd->u.scan < WORK_UNIT_WORDS / 2)) { + if (ws->todo_free + size < bd->start + bd->blocks * BLOCK_SIZE_W) { + ws->todo_lim = stg_min(bd->start + bd->blocks * BLOCK_SIZE_W, + ws->todo_lim + stg_max(WORK_UNIT_WORDS,size)); + debugTrace(DEBUG_gc, "increasing limit for %p to %p", bd->start, ws->todo_lim); + p = ws->todo_free; + ws->todo_free += size; + return p; + } } + + gct->copied += ws->todo_free - bd->free; + bd->free = ws->todo_free; + + ASSERT(bd->u.scan >= bd->start && bd->u.scan <= bd->free); - bd->link = stp->blocks; - stp->blocks = bd; + // If this block is not the scan block, we want to push it out and + // make room for a new todo block. + if (bd != gct->scan_bd) + { + // If this block does not have enough space to allocate the + // current object, but it also doesn't have any work to push, then + // push it on to the scanned list. It cannot be empty, because + // then there would be enough room to copy the current object. + if (bd->u.scan == bd->free) + { + ASSERT(bd->free != bd->start); + push_scanned_block(bd, ws); + } + // Otherwise, push this block out to the global list. + else + { + step *stp; + stp = ws->step; + debugTrace(DEBUG_gc, "push todo block %p (%ld words), step %d, todo_q: %ld", + bd->start, (unsigned long)(bd->free - bd->u.scan), + stp->abs_no, dequeElements(ws->todo_q)); - if (stp->scavd_hp != NULL) { - Bdescr(stp->scavd_hp)->free = stp->scavd_hp; + if (!pushWSDeque(ws->todo_q, bd)) { + bd->link = ws->todo_overflow; + ws->todo_overflow = bd; + ws->n_todo_overflow++; + } + } } - stp->scavd_hp = bd->start; - stp->scavd_hpLim = stp->scavd_hp + BLOCK_SIZE_W; - stp->n_blocks++; - new_scavd_blocks++; + ws->todo_bd = NULL; + ws->todo_free = NULL; + ws->todo_lim = NULL; - return bd; + alloc_todo_block(ws, size); + + p = ws->todo_free; + ws->todo_free += size; + return p; +} + +StgPtr +alloc_todo_block (step_workspace *ws, nat size) +{ + bdescr *bd/*, *hd, *tl */; + + // Grab a part block if we have one, and it has enough room + bd = ws->part_list; + if (bd != NULL && + bd->start + bd->blocks * BLOCK_SIZE_W - bd->free > (int)size) + { + ws->part_list = bd->link; + ws->n_part_blocks -= bd->blocks; + } + else + { + // blocks in to-space get the BF_EVACUATED flag. + +// allocBlocks_sync(16, &hd, &tl, +// ws->step->gen_no, ws->step, BF_EVACUATED); +// +// tl->link = ws->part_list; +// ws->part_list = hd->link; +// ws->n_part_blocks += 15; +// +// bd = hd; + + if (size > BLOCK_SIZE_W) { + bd = allocGroup_sync((lnat)BLOCK_ROUND_UP(size*sizeof(W_)) + / BLOCK_SIZE); + } else { + bd = allocBlock_sync(); + } + initBdescr(bd, ws->step); + bd->flags = BF_EVACUATED; + bd->u.scan = bd->free = bd->start; + } + + bd->link = NULL; + + ws->todo_bd = bd; + ws->todo_free = bd->free; + ws->todo_lim = stg_min(bd->start + bd->blocks * BLOCK_SIZE_W, + bd->free + stg_max(WORK_UNIT_WORDS,size)); + + debugTrace(DEBUG_gc, "alloc new todo block %p for step %d", + bd->free, ws->step->abs_no); + + return ws->todo_free; } +/* ----------------------------------------------------------------------------- + * Debugging + * -------------------------------------------------------------------------- */ + +#if DEBUG +void +printMutableList(generation *gen) +{ + bdescr *bd; + StgPtr p; + + debugBelch("mutable list %p: ", gen->mut_list); + + for (bd = gen->mut_list; bd != NULL; bd = bd->link) { + for (p = bd->start; p < bd->free; p++) { + debugBelch("%p (%s), ", (void *)*p, info_type((StgClosure *)*p)); + } + } + debugBelch("\n"); +} +#endif /* DEBUG */