The unpac monorepo manager self-hosting as a monorepo using unpac
Merge pull request #11046 from gasche/minor_heap_decommit_fix
minor bugfix in caml_reallocate_minor_heap
authored by
Gabriel Scherer
and committed by
GitHub
a8bec243
e23c7c37
+45
-3
+45
-3
runtime/domain.c
+45
-3
runtime/domain.c
···
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return Wsize_bsize(bs);
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}
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/* The current minor heap layout is as follows:
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- A contiguous memory block of size [Minor_heap_max * Max_domains]
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is reserved by [caml_init_domains]. The boundaries of this
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reserved area are stored in the globals
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[caml_minor_heaps_base]
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and
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[caml_minor_heaps_base_end}.
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- Each domain gets a reserved section of this block of size
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[Minor_heap_max], whose boundaries are stored as
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[domain_self->minor_heap_base]
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and
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[domain_self->minor_heap_base_end]
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- Each domain then commits a segment of size
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[domain_state->minor_heap_wsz]
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starting at
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[domain_state->minor_heap_base]
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that it actually uses.
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This is done below in
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[caml_reallocate_minor_heap]
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which is called both at domain-initialization (by [create_domain])
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and if a request comes to change the minor heap size.
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The boundaries of this committed memory area are
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[domain_state->young_start]
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and
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[domain_state->young_end].
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*/
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int caml_reallocate_minor_heap(asize_t wsize)
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{
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caml_domain_state* domain_state = Caml_state;
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CAMLassert(domain_state->young_ptr == domain_state->young_end);
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CAMLassert(
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(/* unitialized minor heap */
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domain_state->young_start == NULL
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&& domain_state->young_end == NULL)
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||
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(/* initialized minor heap */
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domain_state->young_start == (value*)domain_self->minor_heap_area
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&& domain_state->young_end < (value*)domain_self->minor_heap_area_end));
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/* free old minor heap.
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instead of unmapping the heap, we decommit it, so there's
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no race whereby other code could attempt to reuse the memory. */
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caml_mem_decommit(
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(void*)domain_self->minor_heap_area,
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domain_self->minor_heap_area_end - domain_self->minor_heap_area);
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(char*)domain_state->young_end - (char*)domain_state->young_start);
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wsize = caml_norm_minor_heap_size(wsize);
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···
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goto init_signal_stack_failure;
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}
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-
domain_state->young_start = domain_state->young_end =
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domain_state->young_ptr = 0;
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domain_state->young_start =
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domain_state->young_end =
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domain_state->young_ptr = NULL;
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domain_state->minor_tables = caml_alloc_minor_tables();
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if(domain_state->minor_tables == NULL) {
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goto alloc_minor_tables_failure;