From bc0a080a33298df20efe34aaf62d558e3875eba2 Mon Sep 17 00:00:00 2001 From: Pedro Alves Date: Mon, 5 Dec 2022 20:44:39 +0000 Subject: [PATCH] Move deleting thread on TARGET_WAITKIND_THREAD_EXITED to core Currently, infrun assumes that when TARGET_WAITKIND_THREAD_EXITED is reported, the corresponding GDB thread has already been removed from the GDB thread list. Later in the series, that will no longer work, as infrun will need to refer to the thread's thread_info when it processes TARGET_WAITKIND_THREAD_EXITED. As preparation, this patch makes deleting the GDB thread responsibility of infrun, instead of the target. Change-Id: I013d87f61ffc9aaca49f0d6ce2a43e3ea69274de --- gdb/infrun.c | 31 ++++++++++++++++++++++++++----- gdb/linux-nat.c | 22 +++++++++++++++------- gdb/netbsd-nat.c | 1 - 3 files changed, 41 insertions(+), 13 deletions(-) diff --git a/gdb/infrun.c b/gdb/infrun.c index e5f8dc8d8ab..329b6e1dd28 100644 --- a/gdb/infrun.c +++ b/gdb/infrun.c @@ -4239,7 +4239,12 @@ reinstall_readline_callback_handler_cleanup () } /* Clean up the FSMs of threads that are now stopped. In non-stop, - that's just the event thread. In all-stop, that's all threads. */ + that's just the event thread. In all-stop, that's all threads. In + all-stop, threads that had a pending exit no longer have a reason + to be around, as their FSMs/commands are canceled, so we delete + them. This avoids "info threads" listing such threads as if they + were alive (and failing to read their registers), the user being to + select and resume them (and that failing), etc. */ static void clean_up_just_stopped_threads_fsms (struct execution_control_state *ecs) @@ -4257,15 +4262,28 @@ clean_up_just_stopped_threads_fsms (struct execution_control_state *ecs) { scoped_restore_current_thread restore_thread; - for (thread_info *thr : all_non_exited_threads ()) + for (thread_info *thr : all_threads_safe ()) { - if (thr->thread_fsm () == nullptr) + if (thr->state == THREAD_EXITED) continue; + if (thr == ecs->event_thread) continue; - switch_to_thread (thr); - thr->thread_fsm ()->clean_up (thr); + if (thr->thread_fsm () != nullptr) + { + switch_to_thread (thr); + thr->thread_fsm ()->clean_up (thr); + } + + /* As we are cancelling the command/FSM of this thread, + whatever was the reason we needed to report a thread + exited event to the user, that reason is gone. Delete + the thread, so that the user doesn't see it in the thread + list, the next proceed doesn't try to resume it, etc. */ + if (thr->has_pending_waitstatus () + && thr->pending_waitstatus ().kind () == TARGET_WAITKIND_THREAD_EXITED) + delete_thread (thr); } } } @@ -5591,6 +5609,9 @@ handle_inferior_event (struct execution_control_state *ecs) if (ecs->ws.kind () == TARGET_WAITKIND_THREAD_EXITED) { + ecs->event_thread = find_thread_ptid (ecs->target, ecs->ptid); + gdb_assert (ecs->event_thread != nullptr); + delete_thread (ecs->event_thread); prepare_to_wait (ecs); return; } diff --git a/gdb/linux-nat.c b/gdb/linux-nat.c index 816a5a0491c..e97d2262f7f 100644 --- a/gdb/linux-nat.c +++ b/gdb/linux-nat.c @@ -898,10 +898,11 @@ linux_nat_switch_fork (ptid_t new_ptid) registers_changed (); } -/* Handle the exit of a single thread LP. */ +/* Handle the exit of a single thread LP. If DEL_THREAD is true, + delete the thread_info associated to LP, if it exists. */ static void -exit_lwp (struct lwp_info *lp) +exit_lwp (struct lwp_info *lp, bool del_thread = true) { struct thread_info *th = find_thread_ptid (linux_target, lp->ptid); @@ -911,7 +912,8 @@ exit_lwp (struct lwp_info *lp) gdb_printf (_("[%s exited]\n"), target_pid_to_str (lp->ptid).c_str ()); - delete_thread (th); + if (del_thread) + delete_thread (th); } delete_lwp (lp->ptid); @@ -3138,11 +3140,17 @@ filter_exit_event (struct lwp_info *event_child, if (!is_leader (event_child)) { if (report_thread_events) - ourstatus->set_thread_exited (0); + { + ourstatus->set_thread_exited (0); + /* Delete lwp, but not thread_info, infrun will need it to + process the event. */ + exit_lwp (event_child, false); + } else - ourstatus->set_ignore (); - - exit_lwp (event_child); + { + ourstatus->set_ignore (); + exit_lwp (event_child); + } } return ptid; diff --git a/gdb/netbsd-nat.c b/gdb/netbsd-nat.c index 64f74c9405c..37f2fa49b0b 100644 --- a/gdb/netbsd-nat.c +++ b/gdb/netbsd-nat.c @@ -629,7 +629,6 @@ nbsd_nat_target::wait (ptid_t ptid, struct target_waitstatus *ourstatus, if (print_thread_events) gdb_printf (_("[%s exited]\n"), target_pid_to_str (wptid).c_str ()); - delete_thread (thr); } /* The GDB core expects that the rest of the threads are running. */ -- 2.47.2