From aa01bd3689d204ce3d657cf7eb17b8343d79a080 Mon Sep 17 00:00:00 2001 From: Pedro Alves Date: Tue, 24 May 2016 14:47:56 +0100 Subject: Linux native thread create/exit events support A following patch (fix for gdb/19828) makes linux-nat.c add threads to GDB's thread list earlier in the "attach" sequence, and that causes a surprising regression on gdb.threads/attach-many-short-lived-threads.exp on my machine. The extra "thread x exited" handling and traffic slows down that test enough that GDB core has trouble keeping up with new threads that are spawned while trying to stop existing ones. I saw the exact same issue with remote/gdbserver a while ago and fixed it in 65706a29bac5 (Remote thread create/exit events) so part of the fix here is the exact same -- add support for thread created events to gdb/linux-nat.c. infrun.c:stop_all_threads enables those events when it tries to stop threads, which ensures that new threads never get a chance to themselves start new threads, thus fixing the race. gdb/ 2016-05-24 Pedro Alves PR gdb/19828 * linux-nat.c (report_thread_events): New global. (linux_handle_extended_wait): Report TARGET_WAITKIND_THREAD_CREATED if thread event reporting is enabled. (wait_lwp, linux_nat_filter_event): Report all thread exits if thread event reporting is enabled. Remove comment. (filter_exit_event): New function. (linux_nat_wait_1): Use it. (linux_nat_thread_events): New function. (linux_nat_add_target): Install it as target_thread_events method. --- gdb/linux-thread-db.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) (limited to 'gdb/linux-thread-db.c') diff --git a/gdb/linux-thread-db.c b/gdb/linux-thread-db.c index 284e331..2300c81 100644 --- a/gdb/linux-thread-db.c +++ b/gdb/linux-thread-db.c @@ -1116,12 +1116,14 @@ thread_db_wait (struct target_ops *ops, ptid = beneath->to_wait (beneath, ptid, ourstatus, options); - if (ourstatus->kind == TARGET_WAITKIND_IGNORE) - return ptid; - - if (ourstatus->kind == TARGET_WAITKIND_EXITED - || ourstatus->kind == TARGET_WAITKIND_SIGNALLED) - return ptid; + switch (ourstatus->kind) + { + case TARGET_WAITKIND_IGNORE: + case TARGET_WAITKIND_EXITED: + case TARGET_WAITKIND_THREAD_EXITED: + case TARGET_WAITKIND_SIGNALLED: + return ptid; + } info = get_thread_db_info (ptid_get_pid (ptid)); -- cgit v1.1