Issue #6433 has been updated by ibc (Iñaki Baz Castillo). ko1 (Koichi Sasada) wrote: > (2012/05/14 21:57), ibc (Iñaki Baz Castillo) wrote: > > So... is ubf() called with the GVL or not?? > > No. ubf() will call *without* GVL. I'm not sure why your code said > such error. Can you show us a reproduce-able small code? My code clearly says "[BUG] rb_thread_call_with_gvl: called by a thread which has GVL.". You can reproduce it by downloading it (Ruby 1.9.2 or perhasp 1.9.3 required): ~# git clone git://github.com/ibc/AsyncEngine.git ~# cd AsyncEngine/ ~# rake (it should success) ~# cd test/others/ ~# ruby crash_ubf_with_gvl.rb C DBG: run_uv_without_gvl() starts ..........C NOTICE: ae_thread_killed() starts, running rb_thread_call_with_gvl(terminate_uv_with_gvl, NULL)... crash_ubf_with_gvl.rb:15: [BUG] rb_thread_call_with_gvl: called by a thread which has GVL. ruby 1.9.2p0 (2010-08-18 revision 29036) [x86_64-linux] -- control frame ---------- c:0004 p:---- s:0010 b:0010 l:000009 d:000009 CFUNC :kill c:0003 p:0111 s:0007 b:0007 l:000f08 d:000d60 EVAL crash_ubf_with_gvl.rb:15 c:0002 p:---- s:0004 b:0004 l:000003 d:000003 FINISH c:0001 p:0000 s:0002 b:0002 l:000f08 d:000f08 TOP --------------------------- -- Ruby level backtrace information ---------------------------------------- crash_ubf_with_gvl.rb:15:in `<main>' crash_ubf_with_gvl.rb:15:in `kill' -- C level backtrace information ------------------------------------------- /usr/lib/libruby-1.9.1.so.1.9(rb_vm_bugreport+0x5f) [0x7fdcfff64b1f] /usr/lib/libruby-1.9.1.so.1.9(+0x5b304) [0x7fdcffe70304] /usr/lib/libruby-1.9.1.so.1.9(rb_bug+0xb3) [0x7fdcffe70473] /usr/lib/libruby-1.9.1.so.1.9(rb_thread_call_with_gvl+0x160) [0x7fdcfff68680] /tmp/kk/AsyncEngine/lib/asyncengine/asyncengine_ext.so(+0xf0f4) [0x7fdcfe8890f4] /usr/lib/libruby-1.9.1.so.1.9(rb_threadptr_interrupt+0x3c) [0x7fdcfff659bc] /usr/lib/libruby-1.9.1.so.1.9(rb_thread_kill+0x48) [0x7fdcfff680a8] /usr/lib/libruby-1.9.1.so.1.9(+0x148be8) [0x7fdcfff5dbe8] /usr/lib/libruby-1.9.1.so.1.9(+0x140dd0) [0x7fdcfff55dd0] /usr/lib/libruby-1.9.1.so.1.9(+0x1457f1) [0x7fdcfff5a7f1] /usr/lib/libruby-1.9.1.so.1.9(rb_iseq_eval_main+0xb2) [0x7fdcfff5aa42] /usr/lib/libruby-1.9.1.so.1.9(+0x5e4c2) [0x7fdcffe734c2] /usr/lib/libruby-1.9.1.so.1.9(ruby_exec_node+0x1d) [0x7fdcffe734ed] /usr/lib/libruby-1.9.1.so.1.9(ruby_run_node+0x1e) [0x7fdcffe74dae] ruby(main+0x4b) [0x40099b] /lib/libc.so.6(__libc_start_main+0xfd) [0x7fdcfeff0c8d] ruby() [0x400889] ----------------------------------------------------------------- The main C file is ext/asyncengine/asyncengine_ruby.c. lib/asyncengine.rb contains the method AsyncEngine.run (AE.run) which invockes AE._c_run defined in asyncengine_ruby.c. This method uses rb_thread_call_without_gvl() to start the UV loop, which blocks. When an event occurs, the Ruby callback is called with rb_thread_call_with_gvl() (this works ok). When a signal (i.e. Interrupted) is received in the thread running AE, the ubf function ae_thread_killed() is called, and that function uses rb_thread_call_with_gvl(terminate_uv_with_gvl, NULL). The function terminate_uv_with_gvl() runs the Ruby method AE.stop, which iterates over all the existing UV handles (in a @_handles Hash) and invokes #destroy on each of them, so they are closed by UV and the C blocking function uv_run() exits. So I need to run AE.stop from the ubf function since it's hard to clean a Hash from C (rb_hash_clear is not public). The problem is that, when the ubf function calls to rb_thread_call_with_gvl(terminate_uv_with_gvl, NULL), the above error occurs. > PS1: I'm surprising that you want to invoke Ruby code. I only imagine > ubf() as a small code such as "toggle cancel flag" or "kick some API to > cancel invoking situation". Maybe you shouldn't use Ruby code (Ruby > code can be run after blocking process is canceled). uv_run() (from the C library UV) just exits when all its handles have been closed with the uv_close() function. I store the uv handles within C structures in Ruby AsyncEngine classes (i.e. AsyncEngine::Timer), so I need to iterate over all the Ruby AsyncEngine::XXXXX instances (stored in AE.@_handles) and invoke the #destroy method on them. ---------------------------------------- Bug #6433: rb_thread_blocking_region(): ubf() function is executed with GVL https://bugs.ruby-lang.org/issues/6433#change-26623 Author: ibc (Iñaki Baz Castillo) Status: Open Priority: Normal Assignee: Category: ext Target version: 1.9.2 ruby -v: ruby 1.9.2p290 (2011-07-09 revision 32553) [x86_64-linux] thread.c says: ------------------------ * If another thread interrupts this thread (Thread#kill, signal delivery, * VM-shutdown request, and so on), `ubf()' is called (`ubf()' means * "un-blocking function"). `ubf()' should interrupt `func()' execution. * NOTE: You can not execute most of Ruby C API and touch Ruby * objects in `func()' and `ubf()', including raising an * exception, because current thread doesn't acquire GVL * (cause synchronization problem). VALUE rb_thread_blocking_region( rb_blocking_function_t *func, void *data1, rb_unblock_function_t *ubf, void *data2) -------------------------- I've created my ubf() function which is called when the Ruby thread in which rb_thread_blocking_region() was called is killed or interrupted. Within my ubf() function I expect not to have the GVL (as the doc says) and I need to run Ruby code, so I use: rb_thread_call_with_gvl(terminate_my_C_reactor_with_gvl, NULL); and I get an error: [BUG] rb_thread_call_with_gvl: called by a thread which has GVL. So... is ubf() called with the GVL or not?? -- http://bugs.ruby-lang.org/