mirror/guile
mirror/guile
1
Fork 0
mirror of https://git.savannah.gnu.org/git/guile.git synced 2025-06-10 14:00:21 +02:00
Code Activity

Use atomics when sweeping

Browse source 
Otherwise, there is a race with concurrent marking, though possibly just
during the ragged stop.
This commit is contained in:
Andy Wingo 2022-05-01 16:23:10 +02:00
parent 2a68dadf22
commit f51e969730
1 changed files with 6 additions and 6 deletions
Download patch file Download diff file Expand all files Collapse all files

12
mark-sweep.h
View file

@ -660,27 +660,27 @@ static size_t mark_space_live_object_granules(uint8_t *metadata) {
return n + 1;
}
// FIXME: use atomics
static int sweep_byte(uint8_t *loc, uintptr_t sweep_mask) {
uint8_t metadata = *loc;
uint8_t metadata = atomic_load_explicit(loc, memory_order_relaxed);
// If the metadata byte is nonzero, that means either a young, dead,
// survived, or marked object. If it's live (young, survived, or
// marked), we found the next mark. Otherwise it's dead and we clear
// the byte.
// the byte. If we see an END, that means an end of a dead object;
// clear it.
if (metadata) {
if (metadata & sweep_mask)
return 1;
*loc = 0;
atomic_store_explicit(loc, 0, memory_order_relaxed);
}
return 0;
}
static int sweep_word(uintptr_t *loc, uintptr_t sweep_mask) {
uintptr_t metadata = *loc;
uintptr_t metadata = atomic_load_explicit(loc, memory_order_relaxed);
if (metadata) {
if (metadata & sweep_mask)
return 1;
*loc = 0;
atomic_store_explicit(loc, 0, memory_order_relaxed);
}
return 0;
}