* linux-low.c (linux_kill, linux_detach): Adjust.
(status_pending_p_callback): Remove redundant statement. Check
for !TARGET_WAITIKIND_IGNORE, instead of
TARGET_WAITKIND_STOPPED.
(handle_tracepoints): Make sure LWP is locked. Adjust.
(linux_wait_for_event_1): Adjust.
(linux_cancel_breakpoints): New.
(unsuspend_one_lwp): New.
(unsuspend_all_lwps): New.
(linux_wait_1): If finishing a step-over, unsuspend all lwps.
(send_sigstop_callback): Change return type to int, add new
`except' parameter and handle it.
(suspend_and_send_sigstop_callback): New.
(stop_all_lwps): Add new `suspend' and `expect' parameters, and
pass them down. If SUSPEND, also increment the lwp's suspend
count.
(linux_resume_one_lwp): Add notice about resuming a suspended LWP.
(need_step_over_p): Don't consider suspended LWPs.
(start_step_over): Adjust.
(proceed_one_lwp): Change return type to int, add new `except'
parameter and handle it.
(unsuspend_and_proceed_one_lwp): New.
(proceed_all_lwps): Use find_inferior instead of
for_each_inferior.
(unstop_all_lwps): Add `unsuspend' parameter. If UNSUSPEND, them
also decrement the suspend count of LWPs. Pass `except' down,
instead of hacking its suspend count.
(linux_pause_all): Add `freeze' parameter. Adjust.
(linux_unpause_all): New.
(linux_target_ops): Install linux_unpause_all.
* server.c (handle_status): Adjust.
* target.h (struct target_ops): New fields `unpause_all' and
`cancel_breakpoints'. Add new parameter to `pause_all'.
(pause_all): Add new `freeze' parameter.
(unpause_all): New.
(cancel_breakpoints): New.
* tracepoint.c (clear_installed_tracepoints): Pause threads, and
cancel breakpoints.
(cmd_qtstart): Pause threads.
(stop_tracing): Pause threads, and cancel breakpoints.
* win32-low.c (win32_target_ops): Adjust.