diff options
| author | KJ Tsanaktsidis <kj@kjtsanaktsidis.id.au> | 2023-05-21 22:29:16 +1000 |
|---|---|---|
| committer | Nobuyoshi Nakada <nobu@ruby-lang.org> | 2023-05-26 14:51:23 +0900 |
| commit | 66871c5a06d723f8350935ced1e88d8cc929d809 (patch) | |
| tree | 71cf77cf24923b1c10695a1b07e06742353cbfc8 /common.mk | |
| parent | 54a74c42033e42869e69e7dc9e67efa1faf225be (diff) | |
Fix busy-loop when waiting for file descriptors to close
When one thread is closing a file descriptor whilst another thread is
concurrently reading it, we need to wait for the reading thread to be
done with it to prevent a potential EBADF (or, worse, file descriptor
reuse).
At the moment, that is done by keeping a list of threads still using the
file descriptor in io_close_fptr. It then continually calls
rb_thread_schedule() in fptr_finalize_flush until said list is empty.
That busy-looping seems to behave rather poorly on some OS's,
particulary FreeBSD. It can cause the TestIO#test_race_gets_and_close
test to fail (even with its very long 200 second timeout) because the
closing thread starves out the using thread.
To fix that, I introduce the concept of struct rb_io_close_wait_list; a
list of threads still using a file descriptor that we want to close. We
call `rb_notify_fd_close` to let the thread scheduler know we're closing
a FD, which fills the list with threads. Then, we call
rb_notify_fd_close_wait which will block the thread until all of the
still-using threads are done.
This is implemented with a condition variable sleep, so no busy-looping
is required.
Notes
Notes:
Merged: https://github.com/ruby/ruby/pull/7865
Diffstat (limited to 'common.mk')
| -rw-r--r-- | common.mk | 10 |
1 files changed, 10 insertions, 0 deletions
@@ -6576,6 +6576,10 @@ explicit_bzero.$(OBJEXT): {$(VPATH)}internal/config.h explicit_bzero.$(OBJEXT): {$(VPATH)}internal/dllexport.h explicit_bzero.$(OBJEXT): {$(VPATH)}internal/has/attribute.h explicit_bzero.$(OBJEXT): {$(VPATH)}missing.h +file.$(OBJEXT): $(CCAN_DIR)/check_type/check_type.h +file.$(OBJEXT): $(CCAN_DIR)/container_of/container_of.h +file.$(OBJEXT): $(CCAN_DIR)/list/list.h +file.$(OBJEXT): $(CCAN_DIR)/str/str.h file.$(OBJEXT): $(hdrdir)/ruby/ruby.h file.$(OBJEXT): $(top_srcdir)/internal/array.h file.$(OBJEXT): $(top_srcdir)/internal/class.h @@ -6773,6 +6777,7 @@ file.$(OBJEXT): {$(VPATH)}shape.h file.$(OBJEXT): {$(VPATH)}st.h file.$(OBJEXT): {$(VPATH)}subst.h file.$(OBJEXT): {$(VPATH)}thread.h +file.$(OBJEXT): {$(VPATH)}thread_native.h file.$(OBJEXT): {$(VPATH)}util.h gc.$(OBJEXT): $(CCAN_DIR)/check_type/check_type.h gc.$(OBJEXT): $(CCAN_DIR)/container_of/container_of.h @@ -7810,6 +7815,10 @@ io.$(OBJEXT): {$(VPATH)}thread_native.h io.$(OBJEXT): {$(VPATH)}util.h io.$(OBJEXT): {$(VPATH)}vm_core.h io.$(OBJEXT): {$(VPATH)}vm_opts.h +io_buffer.$(OBJEXT): $(CCAN_DIR)/check_type/check_type.h +io_buffer.$(OBJEXT): $(CCAN_DIR)/container_of/container_of.h +io_buffer.$(OBJEXT): $(CCAN_DIR)/list/list.h +io_buffer.$(OBJEXT): $(CCAN_DIR)/str/str.h io_buffer.$(OBJEXT): $(hdrdir)/ruby/ruby.h io_buffer.$(OBJEXT): $(top_srcdir)/internal/array.h io_buffer.$(OBJEXT): $(top_srcdir)/internal/bignum.h @@ -7995,6 +8004,7 @@ io_buffer.$(OBJEXT): {$(VPATH)}onigmo.h io_buffer.$(OBJEXT): {$(VPATH)}oniguruma.h io_buffer.$(OBJEXT): {$(VPATH)}st.h io_buffer.$(OBJEXT): {$(VPATH)}subst.h +io_buffer.$(OBJEXT): {$(VPATH)}thread_native.h iseq.$(OBJEXT): $(CCAN_DIR)/check_type/check_type.h iseq.$(OBJEXT): $(CCAN_DIR)/container_of/container_of.h iseq.$(OBJEXT): $(CCAN_DIR)/list/list.h |