Skip to content

Avoid taking vm barrier in heap_prepare() #14425

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
luke-gru merged 1 commit into from
Nov 3, 2025
Merged

Avoid taking vm barrier in heap_prepare() #14425

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
12 changes: 8 additions & 4 deletions gc/default/default.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -985,6 +985,9 @@ total_final_slots_count(rb_objspace_t *objspace)
#define GC_INCREMENTAL_SWEEP_SLOT_COUNT 2048
#define GC_INCREMENTAL_SWEEP_POOL_SLOT_COUNT 1024
#define is_lazy_sweeping(objspace) (GC_ENABLE_LAZY_SWEEP && has_sweeping_pages(objspace))
/* In lazy sweeping or the previous incremental marking finished and did not yield a free page. */
#define needs_continue_sweeping(objspace, heap) \
((heap)->free_pages == NULL && is_lazy_sweeping(objspace))

#if SIZEOF_LONG == SIZEOF_VOIDP
# define obj_id_to_ref(objid) ((objid) ^ FIXNUM_FLAG) /* unset FIXNUM_FLAG */
Expand Down Expand Up @@ -2022,7 +2025,10 @@ static void
gc_continue(rb_objspace_t *objspace, rb_heap_t *heap)
{
unsigned int lock_lev;
gc_enter(objspace, gc_enter_event_continue, &lock_lev);
bool needs_gc = is_incremental_marking(objspace) || needs_continue_sweeping(objspace, heap);
if (!needs_gc) return;

gc_enter(objspace, gc_enter_event_continue, &lock_lev); // takes vm barrier, try to avoid

/* Continue marking if in incremental marking. */
if (is_incremental_marking(objspace)) {
Expand All @@ -2031,9 +2037,7 @@ gc_continue(rb_objspace_t *objspace, rb_heap_t *heap)
}
}

/* Continue sweeping if in lazy sweeping or the previous incremental
* marking finished and did not yield a free page. */
if (heap->free_pages == NULL && is_lazy_sweeping(objspace)) {
if (needs_continue_sweeping(objspace, heap)) {
gc_sweep_continue(objspace, heap);
}

Expand Down
Loading