nixpkgs-suyu/pkgs/tools/package-management/nix/patches/boehmgc-coroutine-sp-fallback.patch
2022-01-26 10:31:48 -08:00

45 lines
2 KiB
Diff

diff --git a/pthread_stop_world.c b/pthread_stop_world.c
index 4b2c429..1fb4c52 100644
--- a/pthread_stop_world.c
+++ b/pthread_stop_world.c
@@ -673,6 +673,8 @@ GC_INNER void GC_push_all_stacks(void)
struct GC_traced_stack_sect_s *traced_stack_sect;
pthread_t self = pthread_self();
word total_size = 0;
+ size_t stack_limit;
+ pthread_attr_t pattr;
if (!EXPECT(GC_thr_initialized, TRUE))
GC_thr_init();
@@ -722,6 +724,31 @@ GC_INNER void GC_push_all_stacks(void)
hi = p->altstack + p->altstack_size;
/* FIXME: Need to scan the normal stack too, but how ? */
/* FIXME: Assume stack grows down */
+ } else {
+ if (pthread_getattr_np(p->id, &pattr)) {
+ ABORT("GC_push_all_stacks: pthread_getattr_np failed!");
+ }
+ if (pthread_attr_getstacksize(&pattr, &stack_limit)) {
+ ABORT("GC_push_all_stacks: pthread_attr_getstacksize failed!");
+ }
+ if (pthread_attr_destroy(&pattr)) {
+ ABORT("GC_push_all_stacks: pthread_attr_destroy failed!");
+ }
+ // When a thread goes into a coroutine, we lose its original sp until
+ // control flow returns to the thread.
+ // While in the coroutine, the sp points outside the thread stack,
+ // so we can detect this and push the entire thread stack instead,
+ // as an approximation.
+ // We assume that the coroutine has similarly added its entire stack.
+ // This could be made accurate by cooperating with the application
+ // via new functions and/or callbacks.
+ #ifndef STACK_GROWS_UP
+ if (lo >= hi || lo < hi - stack_limit) { // sp outside stack
+ lo = hi - stack_limit;
+ }
+ #else
+ #error "STACK_GROWS_UP not supported in boost_coroutine2 (as of june 2021), so we don't support it in Nix."
+ #endif
}
GC_push_all_stack_sections(lo, hi, traced_stack_sect);
# ifdef STACK_GROWS_UP