From c5848e6dddaabc8e43313f44e1058ed059bee005 Mon Sep 17 00:00:00 2001
From: Ben Gamari <ben@smart-cactus.org>
Date: Thu, 29 Nov 2018 14:05:35 -0500
Subject: [PATCH] Drop bdescr.gen
It's ultimately just a much less space-efficient encoding of bdescr.gen_no.
---
includes/rts/storage/Block.h | 6 ++----
includes/rts/storage/GC.h | 1 -
rts/Arena.c | 1 -
rts/Schedule.c | 2 +-
rts/sm/BlockAlloc.c | 2 --
rts/sm/CNF.c | 4 ++--
rts/sm/Evac.c | 4 ++--
rts/sm/GC.c | 1 -
rts/sm/GCUtils.c | 4 ++--
rts/sm/MarkWeak.c | 4 ++--
rts/sm/NonMovingMark.c | 8 ++++----
rts/sm/NonMovingSweep.c | 2 +-
rts/sm/Sanity.c | 2 +-
rts/sm/Scav.c | 2 +-
rts/sm/Storage.c | 1 -
15 files changed, 18 insertions(+), 26 deletions(-)
diff --git a/includes/rts/storage/Block.h b/includes/rts/storage/Block.h
index d6b440d862bf..d46e8e6282d3 100644
--- a/includes/rts/storage/Block.h
+++ b/includes/rts/storage/Block.h
@@ -112,8 +112,6 @@ typedef struct bdescr_ {
StgPtr scan; // scan pointer for copying GC
} u;
- struct generation_ *gen; // generation
-
StgWord16 gen_no; // gen->no, cached
StgWord16 dest_no; // number of destination generation
StgWord16 node; // which memory node does this block live on?
@@ -124,9 +122,9 @@ typedef struct bdescr_ {
// (if group head, 0 otherwise)
#if SIZEOF_VOID_P == 8
- StgWord32 _padding[5];
+ StgWord32 _padding[7];
#else
- StgWord32 _padding[1];
+ StgWord32 _padding[2];
#endif
} bdescr;
#endif
diff --git a/includes/rts/storage/GC.h b/includes/rts/storage/GC.h
index 793143301986..45e5142ba5e8 100644
--- a/includes/rts/storage/GC.h
+++ b/includes/rts/storage/GC.h
@@ -244,7 +244,6 @@ extern bool keepCAFs;
INLINE_HEADER void initBdescr(bdescr *bd, generation *gen, generation *dest)
{
- bd->gen = gen;
bd->gen_no = gen->no;
bd->dest_no = dest->no;
diff --git a/rts/Arena.c b/rts/Arena.c
index 799106981a4d..7435c44307fc 100644
--- a/rts/Arena.c
+++ b/rts/Arena.c
@@ -85,7 +85,6 @@ arenaAlloc( Arena *arena, size_t size )
arena_blocks += req_blocks;
bd->gen_no = 0;
- bd->gen = NULL;
bd->dest_no = 0;
bd->flags = 0;
bd->free = bdescr_start(bd);
diff --git a/rts/Schedule.c b/rts/Schedule.c
index 77aca0072af0..fc081a6c8f3d 100644
--- a/rts/Schedule.c
+++ b/rts/Schedule.c
@@ -3140,7 +3140,7 @@ resurrectThreads (StgTSO *threads)
for (tso = threads; tso != END_TSO_QUEUE; tso = next) {
next = tso->global_link;
- gen = Bdescr((P_)tso)->gen;
+ gen = &generations[Bdescr((P_)tso)->gen_no];
tso->global_link = gen->threads;
gen->threads = tso;
diff --git a/rts/sm/BlockAlloc.c b/rts/sm/BlockAlloc.c
index bc60d2969eef..37a517f285fa 100644
--- a/rts/sm/BlockAlloc.c
+++ b/rts/sm/BlockAlloc.c
@@ -56,7 +56,6 @@ static void initMBlock(void *mblock, uint32_t node);
The following fields are not used by the allocator:
bd->flags
bd->gen_no
- bd->gen
bd->dest
Exceptions: we don't maintain invariants for all the blocks within a
@@ -792,7 +791,6 @@ freeGroup(bdescr *p)
node = p->node;
p->free = (void *)-1; /* indicates that this block is free */
- p->gen = NULL;
p->gen_no = 0;
/* fill the block group with garbage if sanity checking is on */
IF_DEBUG(zero_on_gc, memset(bdescr_start(p), 0xaa, (W_)p->blocks * BLOCK_SIZE));
diff --git a/rts/sm/CNF.c b/rts/sm/CNF.c
index c15b1cfc978f..8b66dabce8c5 100644
--- a/rts/sm/CNF.c
+++ b/rts/sm/CNF.c
@@ -194,7 +194,7 @@ compactAllocateBlockInternal(Capability *cap,
// wrong and crash in Sanity)
if (first != NULL) {
block = Bdescr((P_)first);
- g = block->gen;
+ g = &generations[block->gen_no];
} else {
g = g0;
}
@@ -1172,7 +1172,7 @@ compactFixupPointers(StgCompactNFData *str,
total_blocks = str->totalW / BLOCK_SIZE_W;
ACQUIRE_SM_LOCK;
- ASSERT(bd->gen == g0);
+ ASSERT(bd->gen_no == 0);
ASSERT(g0->n_compact_blocks_in_import >= total_blocks);
g0->n_compact_blocks_in_import -= total_blocks;
g0->n_compact_blocks += total_blocks;
diff --git a/rts/sm/Evac.c b/rts/sm/Evac.c
index 71bd59dea800..99b95203562e 100644
--- a/rts/sm/Evac.c
+++ b/rts/sm/Evac.c
@@ -307,8 +307,8 @@ evacuate_large(StgPtr p)
gen_workspace *ws;
bd = Bdescr(p);
- gen = bd->gen;
gen_no = bd->gen_no;
+ gen = &generations[gen_no];
ACQUIRE_SPIN_LOCK(&gen->sync);
// already evacuated?
@@ -458,7 +458,7 @@ evacuate_compact (StgPtr p)
return;
}
- gen = bd->gen;
+ gen = &generations[gen_no];
ACQUIRE_SPIN_LOCK(&gen->sync);
// already evacuated?
diff --git a/rts/sm/GC.c b/rts/sm/GC.c
index 40a6d4d0b3b2..0c150ec26058 100644
--- a/rts/sm/GC.c
+++ b/rts/sm/GC.c
@@ -1642,7 +1642,6 @@ collect_pinned_object_blocks (void)
// Mark objects as belonging to the nonmoving heap
for (bdescr *bd = capabilities[n]->pinned_object_blocks; bd != NULL; bd = bd->link) {
bd->flags |= BF_NONMOVING;
- bd->gen = oldest_gen;
bd->gen_no = oldest_gen->no;
oldest_gen->n_large_words += bd->free - bdescr_start(bd);
oldest_gen->n_large_blocks += bd->blocks;
diff --git a/rts/sm/GCUtils.c b/rts/sm/GCUtils.c
index 918bc3469102..58f7ff7c9f0a 100644
--- a/rts/sm/GCUtils.c
+++ b/rts/sm/GCUtils.c
@@ -141,7 +141,7 @@ push_scanned_block (bdescr *bd, gen_workspace *ws)
{
ASSERT(bd != NULL);
ASSERT(bd->link == NULL);
- ASSERT(bd->gen == ws->gen);
+ ASSERT(bd->gen_no == ws->gen->no);
ASSERT(bd->u.scan == bd->free);
if (bd->blocks == 1 &&
@@ -212,7 +212,7 @@ todo_block_full (uint32_t size, gen_workspace *ws)
ASSERT(bd != NULL);
ASSERT(bd->link == NULL);
- ASSERT(bd->gen == ws->gen);
+ ASSERT(bd->gen_no == ws->gen->no);
// We intentionally set ws->todo_lim lower than the full size of
// the block, so that we can push out some work to the global list
diff --git a/rts/sm/MarkWeak.c b/rts/sm/MarkWeak.c
index 7475b5e6256d..c2e9ec260174 100644
--- a/rts/sm/MarkWeak.c
+++ b/rts/sm/MarkWeak.c
@@ -264,7 +264,7 @@ static bool tidyWeakList(generation *gen)
// Find out which generation this weak ptr is in, and
// move it onto the weak ptr list of that generation.
- new_gen = Bdescr((P_)w)->gen;
+ new_gen = &generations[Bdescr((P_)w)->gen_no];
gct->evac_gen_no = new_gen->no;
gct->failed_to_evac = false;
@@ -351,7 +351,7 @@ static void tidyThreadList (generation *gen)
// move this thread onto the correct threads list.
generation *new_gen;
- new_gen = Bdescr((P_)t)->gen;
+ new_gen = &generations[Bdescr((P_)t)->gen_no];
t->global_link = new_gen->threads;
new_gen->threads = t;
}
diff --git a/rts/sm/NonMovingMark.c b/rts/sm/NonMovingMark.c
index f07c8df84981..a8491eb646a0 100644
--- a/rts/sm/NonMovingMark.c
+++ b/rts/sm/NonMovingMark.c
@@ -481,7 +481,7 @@ void push_closure (MarkQueue *q,
StgClosure **origin)
{
#if defined(DEBUG)
- ASSERT(!HEAP_ALLOCED_GC(p) || (Bdescr((StgPtr) p)->gen == oldest_gen));
+ ASSERT(!HEAP_ALLOCED_GC(p) || (&generations[Bdescr((StgPtr) p)->gen_no] == oldest_gen));
ASSERT(LOOKS_LIKE_CLOSURE_PTR(p));
// Commenting out: too slow
// if (RtsFlags.DebugFlags.sanity) {
@@ -511,7 +511,7 @@ void push_array (MarkQueue *q,
StgWord start_index)
{
// TODO: Push this into callers where they already have the Bdescr
- if (HEAP_ALLOCED_GC(array) && (Bdescr((StgPtr) array)->gen != oldest_gen))
+ if (HEAP_ALLOCED_GC(array) && (&generations[Bdescr((StgPtr) array)->gen_no] != oldest_gen))
return;
MarkQueueEnt ent = {
@@ -663,7 +663,7 @@ STATIC_INLINE bool needs_upd_rem_set_mark(StgClosure *p)
{
// TODO: Deduplicate with mark_closure
bdescr *bd = Bdescr((StgPtr) p);
- if (bd->gen != oldest_gen) {
+ if (&generations[bd->gen_no] != oldest_gen) {
return false;
} else if (bd->flags & BF_LARGE) {
if (! (bd->flags & BF_NONMOVING_SWEEPING)) {
@@ -1249,7 +1249,7 @@ mark_closure (MarkQueue *queue, const StgClosure *p0, StgClosure **origin)
bd = Bdescr((StgPtr) p);
- if (bd->gen != oldest_gen) {
+ if (&generations[bd->gen_no] != oldest_gen) {
// Here we have an object living outside of the non-moving heap. While
// we likely evacuated nearly everything to the nonmoving heap during
// preparation there are nevertheless a few ways in which we might trace
diff --git a/rts/sm/NonMovingSweep.c b/rts/sm/NonMovingSweep.c
index 20b2f6b9a847..190ebe722956 100644
--- a/rts/sm/NonMovingSweep.c
+++ b/rts/sm/NonMovingSweep.c
@@ -166,7 +166,7 @@ static bool is_closure_clean(StgClosure *p)
{
const StgInfoTable *info = get_itbl(p);
-#define CLEAN(ptr) (!HEAP_ALLOCED((StgClosure*) ptr) || Bdescr((StgPtr) ptr)->gen == oldest_gen)
+#define CLEAN(ptr) (!HEAP_ALLOCED((StgClosure*) ptr) || &generations[Bdescr((StgPtr) ptr)->gen_no] == oldest_gen)
switch (info->type) {
case MVAR_CLEAN:
diff --git a/rts/sm/Sanity.c b/rts/sm/Sanity.c
index ce179d86a351..87eb53f43926 100644
--- a/rts/sm/Sanity.c
+++ b/rts/sm/Sanity.c
@@ -792,7 +792,7 @@ checkNurserySanity (nursery *nursery)
prev = NULL;
for (bd = nursery->blocks; bd != NULL; bd = bd->link) {
- ASSERT(bd->gen == g0);
+ ASSERT(bd->gen_no == 0);
ASSERT(bd->u.back == prev);
prev = bd;
blocks += bd->blocks;
diff --git a/rts/sm/Scav.c b/rts/sm/Scav.c
index 5fbf4fd70e2b..3293adaf6adc 100644
--- a/rts/sm/Scav.c
+++ b/rts/sm/Scav.c
@@ -434,7 +434,7 @@ scavenge_block (bdescr *bd)
saved_eager_promotion = gct->eager_promotion;
gct->failed_to_evac = false;
- ws = &gct->gens[bd->gen->no];
+ ws = &gct->gens[bd->gen_no];
p = bd->u.scan;
diff --git a/rts/sm/Storage.c b/rts/sm/Storage.c
index 2ecab78b5b16..a077529acc39 100644
--- a/rts/sm/Storage.c
+++ b/rts/sm/Storage.c
@@ -744,7 +744,6 @@ resetNurseries (void)
for (n = 0; n < n_nurseries; n++) {
for (bd = nurseries[n].blocks; bd; bd = bd->link) {
ASSERT(bd->gen_no == 0);
- ASSERT(bd->gen == g0);
ASSERT(bd->node == capNoToNumaNode(n));
IF_DEBUG(zero_on_gc, memset(bdescr_start(bd), 0xaa, BLOCK_SIZE));
}
--
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