From 0664ba0a67a2e1917ca66fed2174a587d27f3369 Mon Sep 17 00:00:00 2001 From: Robert Hensing Date: Tue, 24 Jan 2023 14:39:45 +0100 Subject: Revert "fixup: remove boehmgc patch" It is still necessary. Please do your research, or f ask the author, which happens to be me. An evaluator like this is not an environment where "it compiles, so it works" will ever hold. This reverts commit 1c40182b12d5fd462c891b597e1a3f9b912502d5. --- boehmgc-coroutine-sp-fallback.diff | 77 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 77 insertions(+) create mode 100644 boehmgc-coroutine-sp-fallback.diff diff --git a/boehmgc-coroutine-sp-fallback.diff b/boehmgc-coroutine-sp-fallback.diff new file mode 100644 index 000000000..8fdafbecb --- /dev/null +++ b/boehmgc-coroutine-sp-fallback.diff @@ -0,0 +1,77 @@ +diff --git a/darwin_stop_world.c b/darwin_stop_world.c +index 3dbaa3fb..36a1d1f7 100644 +--- a/darwin_stop_world.c ++++ b/darwin_stop_world.c +@@ -352,6 +352,7 @@ GC_INNER void GC_push_all_stacks(void) + int nthreads = 0; + word total_size = 0; + mach_msg_type_number_t listcount = (mach_msg_type_number_t)THREAD_TABLE_SZ; ++ size_t stack_limit; + if (!EXPECT(GC_thr_initialized, TRUE)) + GC_thr_init(); + +@@ -407,6 +408,19 @@ GC_INNER void GC_push_all_stacks(void) + GC_push_all_stack_sections(lo, hi, p->traced_stack_sect); + } + if (altstack_lo) { ++ // 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. ++ stack_limit = pthread_get_stacksize_np(p->id); ++ if (altstack_lo >= altstack_hi || altstack_lo < altstack_hi - stack_limit) { // sp outside stack ++ altstack_lo = altstack_hi - stack_limit; ++ } ++ + total_size += altstack_hi - altstack_lo; + GC_push_all_stack(altstack_lo, altstack_hi); + } +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 -- cgit v1.2.3