bdescr *bd;
step *stp;
- stp = ws->stp;
+ stp = ws->step;
bd = NULL;
if (ws->buffer_todo_bd)
return bd;
}
-static void
-push_todo_block (bdescr *bd, step *stp)
+void
+push_scanned_block (bdescr *bd, step_workspace *ws)
{
+ ASSERT(bd != NULL);
ASSERT(bd->link == NULL);
- ACQUIRE_SPIN_LOCK(&stp->sync_todo);
- if (stp->todos_last == NULL) {
- stp->todos_last = bd;
- stp->todos = bd;
- } else {
- stp->todos_last->link = bd;
- stp->todos_last = bd;
+ ASSERT(bd->step == ws->step);
+ ASSERT(bd->u.scan == bd->free);
+
+ if (bd->start + 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++;
+ 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 ++;
+ IF_DEBUG(sanity,
+ ASSERT(countBlocks(ws->scavd_list) == ws->n_scavd_blocks));
}
- stp->n_todos++;
- trace(TRACE_gc|DEBUG_gc, "step %d, n_todos: %d", stp->abs_no, stp->n_todos);
- RELEASE_SPIN_LOCK(&stp->sync_todo);
}
-void
-push_scan_block (bdescr *bd, step_workspace *ws)
+StgPtr
+todo_block_full (nat size, step_workspace *ws)
{
+ bdescr *bd;
+
+ bd = ws->todo_bd;
+
ASSERT(bd != NULL);
ASSERT(bd->link == NULL);
+ ASSERT(bd->step == ws->step);
+
+ bd->free = ws->todo_free;
+
+ // 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 (ws->step->todos != NULL ||
+ (bd->free - bd->u.scan < WORK_UNIT_WORDS / 2)) {
+ if (bd->free + size < bd->start + BLOCK_SIZE_W) {
+ debugTrace(DEBUG_gc, "increasing limit for %p", bd->start);
+ ws->todo_lim = stg_min(bd->start + BLOCK_SIZE_W,
+ ws->todo_lim + stg_max(WORK_UNIT_WORDS,size));
+ return ws->todo_free;
+ }
+ }
+
+ ASSERT(bd->u.scan >= bd->start && bd->u.scan <= bd->free);
+
+ // If this block is not the scan block, we want to push it out and
+ // make room for a new todo block.
+ if (bd != ws->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;
+ trace(TRACE_gc|DEBUG_gc, "push todo block %p (%d words), step %d, n_todos: %d",
+ bd->start, bd->free - bd->u.scan, stp->abs_no, stp->n_todos);
+ // ToDo: use buffer_todo
+ ACQUIRE_SPIN_LOCK(&stp->sync_todo);
+ if (stp->todos_last == NULL) {
+ stp->todos_last = bd;
+ stp->todos = bd;
+ } else {
+ stp->todos_last->link = bd;
+ stp->todos_last = bd;
+ }
+ stp->n_todos++;
+ RELEASE_SPIN_LOCK(&stp->sync_todo);
+ }
+ }
- // update stats: this is a block that has been copied & scavenged
- gct->copied += bd->free - bd->start;
+ ws->todo_bd = NULL;
+ ws->todo_free = NULL;
+ ws->todo_lim = NULL;
- // put the scan block on the ws->scavd_list.
- bd->link = ws->scavd_list;
- ws->scavd_list = bd;
- ws->n_scavd_blocks ++;
+ alloc_todo_block(ws, size);
- IF_DEBUG(sanity,
- ASSERT(countBlocks(ws->scavd_list) == ws->n_scavd_blocks));
+ return ws->todo_free;
}
StgPtr
-gc_alloc_todo_block (step_workspace *ws)
+alloc_todo_block (step_workspace *ws, nat size)
{
bdescr *bd;
- if (ws->todo_bd != NULL) {
- ws->todo_bd->free = ws->todo_free;
+ // Grab a part block if we have one, and it has enough room
+ if (ws->part_list != NULL &&
+ ws->part_list->start + BLOCK_SIZE_W - ws->part_list->free > (int)size)
+ {
+ bd = ws->part_list;
+ ws->part_list = bd->link;
+ ws->n_part_blocks--;
}
-
- // If we already have a todo block, it must be full, so we push it
- // out: first to the buffer_todo_bd, then to the step. BUT, don't
- // push out the block out if it is already the scan block.
- if (ws->todo_bd != NULL && ws->scan_bd != ws->todo_bd) {
- ASSERT(ws->todo_bd->link == NULL);
- if (ws->buffer_todo_bd == NULL) {
- // If the global todo list is empty, push this block
- // out immediately rather than caching it in
- // buffer_todo_bd, because there might be other threads
- // waiting for work.
- if (ws->stp->todos == NULL) {
- push_todo_block(ws->todo_bd, ws->stp);
- } else {
- ws->buffer_todo_bd = ws->todo_bd;
- }
- } else {
- ASSERT(ws->buffer_todo_bd->link == NULL);
- push_todo_block(ws->buffer_todo_bd, ws->stp);
- ws->buffer_todo_bd = ws->todo_bd;
+ else
+ {
+ bd = allocBlock_sync();
+ bd->gen_no = ws->step->gen_no;
+ bd->step = ws->step;
+ bd->u.scan = bd->start;
+
+ // blocks in to-space in generations up to and including N
+ // get the BF_EVACUATED flag.
+ if (ws->step->gen_no <= N) {
+ bd->flags = BF_EVACUATED;
+ } else {
+ bd->flags = 0;
}
- ws->todo_bd = NULL;
- }
-
- bd = allocBlock_sync();
+ }
- bd->gen_no = ws->stp->gen_no;
- bd->step = ws->stp;
bd->link = NULL;
- // blocks in to-space in generations up to and including N
- // get the BF_EVACUATED flag.
- if (ws->stp->gen_no <= N) {
- bd->flags = BF_EVACUATED;
- } else {
- bd->flags = 0;
- }
-
ws->todo_bd = bd;
- ws->todo_free = bd->start;
- ws->todo_lim = bd->start + BLOCK_SIZE_W;
+ ws->todo_free = bd->free;
+ ws->todo_lim = stg_min(bd->start + BLOCK_SIZE_W,
+ bd->free + stg_max(WORK_UNIT_WORDS,size));
+
+ debugTrace(DEBUG_gc, "alloc new todo block %p for step %d",
+ bd->start, ws->step->abs_no);
return ws->todo_free;
}
projects / ghc-hetmet.git / blobdiff