binutils-gdb/gdb/infrun.h

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/* Copyright (C) 1986-2015 Free Software Foundation, Inc.
Add new infrun.h header. Move infrun.c declarations out of inferior.h to a new infrun.h file. Tested by building on: i686-w64-mingw32, enable-targets=all x86_64-linux, enable-targets=all i586-pc-msdosdjgpp And also grepped the whole tree for each symbol moved to find where infrun.h might be necessary. gdb/ 2014-05-22 Pedro Alves <palves@redhat.com> * inferior.h (debug_infrun, debug_displaced, stop_on_solib_events) (sync_execution, sched_multi, step_stop_if_no_debug, non_stop) (disable_randomization, enum exec_direction_kind) (execution_direction, stop_registers, start_remote) (clear_proceed_status, proceed, resume, user_visible_resume_ptid) (wait_for_inferior, normal_stop, get_last_target_status) (prepare_for_detach, fetch_inferior_event, init_wait_for_inferior) (insert_step_resume_breakpoint_at_sal) (follow_inferior_reset_breakpoints, stepping_past_instruction_at) (set_step_info, print_stop_event, signal_stop_state) (signal_print_state, signal_pass_state, signal_stop_update) (signal_print_update, signal_pass_update) (update_signals_program_target, clear_exit_convenience_vars) (displaced_step_dump_bytes, update_observer_mode) (signal_catch_update, gdb_signal_from_command): Move declarations ... * infrun.h: ... to this new file. * amd64-tdep.c: Include infrun.h. * annotate.c: Include infrun.h. * arch-utils.c: Include infrun.h. * arm-linux-tdep.c: Include infrun.h. * arm-tdep.c: Include infrun.h. * break-catch-sig.c: Include infrun.h. * breakpoint.c: Include infrun.h. * common/agent.c: Include infrun.h instead of inferior.h. * corelow.c: Include infrun.h. * event-top.c: Include infrun.h. * go32-nat.c: Include infrun.h. * i386-tdep.c: Include infrun.h. * inf-loop.c: Include infrun.h. * infcall.c: Include infrun.h. * infcmd.c: Include infrun.h. * infrun.c: Include infrun.h. * linux-fork.c: Include infrun.h. * linux-nat.c: Include infrun.h. * linux-thread-db.c: Include infrun.h. * monitor.c: Include infrun.h. * nto-tdep.c: Include infrun.h. * procfs.c: Include infrun.h. * record-btrace.c: Include infrun.h. * record-full.c: Include infrun.h. * remote-m32r-sdi.c: Include infrun.h. * remote-mips.c: Include infrun.h. * remote-notif.c: Include infrun.h. * remote-sim.c: Include infrun.h. * remote.c: Include infrun.h. * reverse.c: Include infrun.h. * rs6000-tdep.c: Include infrun.h. * s390-linux-tdep.c: Include infrun.h. * solib-irix.c: Include infrun.h. * solib-osf.c: Include infrun.h. * solib-svr4.c: Include infrun.h. * target.c: Include infrun.h. * top.c: Include infrun.h. * windows-nat.c: Include infrun.h. * mi/mi-interp.c: Include infrun.h. * mi/mi-main.c: Include infrun.h. * python/py-threadevent.c: Include infrun.h.
2014-05-22 13:29:11 +02:00
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#ifndef INFRUN_H
#define INFRUN_H 1
#include "symtab.h"
struct target_waitstatus;
struct frame_info;
struct address_space;
/* True if we are debugging run control. */
extern unsigned int debug_infrun;
/* True if we are debugging displaced stepping. */
extern int debug_displaced;
/* Nonzero if we want to give control to the user when we're notified
of shared library events by the dynamic linker. */
extern int stop_on_solib_events;
/* Are we simulating synchronous execution? This is used in async gdb
to implement the 'run', 'continue' etc commands, which will not
redisplay the prompt until the execution is actually over. */
extern int sync_execution;
/* True if execution commands resume all threads of all processes by
default; otherwise, resume only threads of the current inferior
process. */
extern int sched_multi;
/* When set, stop the 'step' command if we enter a function which has
no line number information. The normal behavior is that we step
over such function. */
extern int step_stop_if_no_debug;
/* If set, the inferior should be controlled in non-stop mode. In
this mode, each thread is controlled independently. Execution
commands apply only to the selected thread by default, and stop
events stop only the thread that had the event -- the other threads
are kept running freely. */
extern int non_stop;
/* When set (default), the target should attempt to disable the
operating system's address space randomization feature when
starting an inferior. */
extern int disable_randomization;
/* Reverse execution. */
enum exec_direction_kind
{
EXEC_FORWARD,
EXEC_REVERSE
};
/* The current execution direction. This should only be set to enum
exec_direction_kind values. It is only an int to make it
compatible with make_cleanup_restore_integer. */
extern int execution_direction;
extern void start_remote (int from_tty);
Always pass signals to the right thread Currently, GDB can pass a signal to the wrong thread in several different but related scenarios. E.g., if thread 1 stops for signal SIGFOO, the user switches to thread 2, and then issues "continue", SIGFOO is actually delivered to thread 2, not thread 1. This obviously messes up programs that use pthread_kill to send signals to specific threads. This has been a known issue for a long while. Back in 2008 when I made stop_signal be per-thread (2020b7ab), I kept the behavior -- see code in 'proceed' being removed -- wanting to come back to it later. The time has finally come now. The patch fixes this -- on resumption, intercepted signals are always delivered to the thread that had intercepted them. Another example: if thread 1 stops for a breakpoint, the user switches to thread 2, and then issues "signal SIGFOO", SIGFOO is actually delivered to thread 1, not thread 2, because 'proceed' first switches to thread 1 to step over its breakpoint... If the user deletes the breakpoint before issuing "signal FOO", then the signal is delivered to thread 2 (the current thread). "signal SIGFOO" can be used for two things: inject a signal in the program while the program/thread had stopped for none, bypassing "handle nopass"; or changing/suppressing a signal the program had stopped for. These scenarios are really two faces of the same coin, and GDB can't really guess what the user is trying to do. GDB might have intercepted signals in more than one thread even (see the new signal-command-multiple-signals-pending.exp test). At least in the inject case, it's obviously clear to me that the user means to deliver the signal to the currently selected thread, so best is to make the command's behavior consistent and easy to explain. Then, if the user is trying to suppress/change a signal the program had stopped for instead of injecting a new signal, but, the user had changed threads meanwhile, then she will be surprised that with: (gdb) continue Thread 1 stopped for signal SIGFOO. (gdb) thread 2 (gdb) signal SIGBAR ... GDB actually delivers SIGFOO to thread 1, and SIGBAR to thread 2 (with scheduler-locking off, which is the default, because then "signal" or any other resumption command resumes all threads). So the patch makes GDB detect that, and ask for confirmation: (gdb) thread 1 [Switching to thread 1 (Thread 10979)] (gdb) signal SIGUSR2 Note: Thread 3 previously stopped with signal SIGUSR2, User defined signal 2. Thread 2 previously stopped with signal SIGUSR1, User defined signal 1. Continuing thread 1 (the current thread) with specified signal will still deliver the signals noted above to their respective threads. Continue anyway? (y or n) All these scenarios are covered by the new tests. Tested on x86_64 Fedora 20, native and gdbserver. gdb/ 2014-07-25 Pedro Alves <palves@redhat.com> * NEWS: Mention signal passing and "signal" command changes. * gdbthread.h (struct thread_suspend_state) <stop_signal>: Extend comment. * breakpoint.c (until_break_command): Adjust clear_proceed_status call. * infcall.c (run_inferior_call): Adjust clear_proceed_status call. * infcmd.c (proceed_thread_callback, continue_1, step_once) (jump_command): Adjust clear_proceed_status call. (signal_command): Warn if other thread that are resumed have signals that will be delivered. Adjust clear_proceed_status call. (until_next_command, finish_command) (proceed_after_attach_callback, attach_command_post_wait) (attach_command): Adjust clear_proceed_status call. * infrun.c (proceed_after_vfork_done): Likewise. (proceed_after_attach_callback): Adjust comment. (clear_proceed_status_thread): Clear stop_signal if not in pass state. (clear_proceed_status_callback): Delete. (clear_proceed_status): New 'step' parameter. Only clear the proceed status of threads the command being prepared is about to resume. (proceed): If passed in an explicit signal, override stop_signal with it. Don't pass the last stop signal to the thread we're resuming. (init_wait_for_inferior): Adjust clear_proceed_status call. (switch_back_to_stepped_thread): Clear the signal if it should not be passed. * infrun.h (clear_proceed_status): New 'step' parameter. (user_visible_resume_ptid): Add comment. * linux-nat.c (linux_nat_resume_callback): Don't check whether the signal is in pass state. * remote.c (append_pending_thread_resumptions): Likewise. * mi/mi-main.c (proceed_thread): Adjust clear_proceed_status call. gdb/doc/ 2014-07-25 Pedro Alves <palves@redhat.com> Eli Zaretskii <eliz@gnu.org> * gdb.texinfo (Signaling) <signal command>: Explain what happens with multi-threaded programs. gdb/testsuite/ 2014-07-25 Pedro Alves <palves@redhat.com> * gdb.threads/signal-command-handle-nopass.c: New file. * gdb.threads/signal-command-handle-nopass.exp: New file. * gdb.threads/signal-command-multiple-signals-pending.c: New file. * gdb.threads/signal-command-multiple-signals-pending.exp: New file. * gdb.threads/signal-delivered-right-thread.c: New file. * gdb.threads/signal-delivered-right-thread.exp: New file.
2014-07-25 17:57:31 +02:00
/* Clear out all variables saying what to do when inferior is
continued or stepped. First do this, then set the ones you want,
then call `proceed'. STEP indicates whether we're preparing for a
step/stepi command. */
extern void clear_proceed_status (int step);
Add new infrun.h header. Move infrun.c declarations out of inferior.h to a new infrun.h file. Tested by building on: i686-w64-mingw32, enable-targets=all x86_64-linux, enable-targets=all i586-pc-msdosdjgpp And also grepped the whole tree for each symbol moved to find where infrun.h might be necessary. gdb/ 2014-05-22 Pedro Alves <palves@redhat.com> * inferior.h (debug_infrun, debug_displaced, stop_on_solib_events) (sync_execution, sched_multi, step_stop_if_no_debug, non_stop) (disable_randomization, enum exec_direction_kind) (execution_direction, stop_registers, start_remote) (clear_proceed_status, proceed, resume, user_visible_resume_ptid) (wait_for_inferior, normal_stop, get_last_target_status) (prepare_for_detach, fetch_inferior_event, init_wait_for_inferior) (insert_step_resume_breakpoint_at_sal) (follow_inferior_reset_breakpoints, stepping_past_instruction_at) (set_step_info, print_stop_event, signal_stop_state) (signal_print_state, signal_pass_state, signal_stop_update) (signal_print_update, signal_pass_update) (update_signals_program_target, clear_exit_convenience_vars) (displaced_step_dump_bytes, update_observer_mode) (signal_catch_update, gdb_signal_from_command): Move declarations ... * infrun.h: ... to this new file. * amd64-tdep.c: Include infrun.h. * annotate.c: Include infrun.h. * arch-utils.c: Include infrun.h. * arm-linux-tdep.c: Include infrun.h. * arm-tdep.c: Include infrun.h. * break-catch-sig.c: Include infrun.h. * breakpoint.c: Include infrun.h. * common/agent.c: Include infrun.h instead of inferior.h. * corelow.c: Include infrun.h. * event-top.c: Include infrun.h. * go32-nat.c: Include infrun.h. * i386-tdep.c: Include infrun.h. * inf-loop.c: Include infrun.h. * infcall.c: Include infrun.h. * infcmd.c: Include infrun.h. * infrun.c: Include infrun.h. * linux-fork.c: Include infrun.h. * linux-nat.c: Include infrun.h. * linux-thread-db.c: Include infrun.h. * monitor.c: Include infrun.h. * nto-tdep.c: Include infrun.h. * procfs.c: Include infrun.h. * record-btrace.c: Include infrun.h. * record-full.c: Include infrun.h. * remote-m32r-sdi.c: Include infrun.h. * remote-mips.c: Include infrun.h. * remote-notif.c: Include infrun.h. * remote-sim.c: Include infrun.h. * remote.c: Include infrun.h. * reverse.c: Include infrun.h. * rs6000-tdep.c: Include infrun.h. * s390-linux-tdep.c: Include infrun.h. * solib-irix.c: Include infrun.h. * solib-osf.c: Include infrun.h. * solib-svr4.c: Include infrun.h. * target.c: Include infrun.h. * top.c: Include infrun.h. * windows-nat.c: Include infrun.h. * mi/mi-interp.c: Include infrun.h. * mi/mi-main.c: Include infrun.h. * python/py-threadevent.c: Include infrun.h.
2014-05-22 13:29:11 +02:00
Remove 'step' parameters from 'proceed' and 'resume' The "step" parameters of 'proceed' and 'resume' aren't really useful as indication of whether run control wants to single-step the target, as that information must already be retrievable from currently_stepping. In fact, if currently_stepping disagrees with whether we single-stepped the target, then things break. Thus instead of having the same information in two places, this patch removes those parameters. Setting 'step_start_function' is the only user of proceed's 'step' argument, other than passing the 'step' argument down to 'resume' and debug log output. Move that instead to set_step_frame, where we already set other related fields. clear_proceed_status keeps its "step" parameter for now because it needs to know which set of threads should have their state cleared, and is called before the "stepping_command" flag is set. Tested on x86_64 Fedora 20, native and gdbserver. gdb/ChangeLog: 2015-03-24 Pedro Alves <palves@redhat.com> * breakpoint.c (until_break_command): Adjust call to proceed. * gdbthread.h (struct thread_control_state) <stepping_command>: New field. * infcall.c (run_inferior_call): Adjust call to proceed. * infcmd.c (run_command_1, proceed_thread_callback, continue_1): Adjust calls to proceed. (set_step_frame): Set the current thread's step_start_function here. (step_once): Adjust calls to proceed. (jump_command, signal_command, until_next_command) (finish_backward, finish_forward, proceed_after_attach_callback) (attach_command_post_wait): Adjust calls to proceed. * infrun.c (proceed_after_vfork_done): Adjust call to proceed. (do_target_resume): New function, factored out from ... (resume): ... here. Remove 'step' parameter. Instead, check currently_stepping to determine whether the thread should be single-stepped. (proceed): Remove 'step' parameter and don't set the thread's step_start_function here. Adjust call to 'resume'. (handle_inferior_event): Adjust calls to 'resume'. (switch_back_to_stepped_thread): Use do_target_resume instead of 'resume'. (keep_going): Adjust calls to 'resume'. * infrun.h (proceed): Remove 'step' parameter. (resume): Likewise. * windows-nat.c (do_initial_windows_stuff): Adjust call to 'resume'. * mi/mi-main.c (proceed_thread): Adjust call to 'proceed'.
2015-03-24 18:50:31 +01:00
extern void proceed (CORE_ADDR, enum gdb_signal);
Add new infrun.h header. Move infrun.c declarations out of inferior.h to a new infrun.h file. Tested by building on: i686-w64-mingw32, enable-targets=all x86_64-linux, enable-targets=all i586-pc-msdosdjgpp And also grepped the whole tree for each symbol moved to find where infrun.h might be necessary. gdb/ 2014-05-22 Pedro Alves <palves@redhat.com> * inferior.h (debug_infrun, debug_displaced, stop_on_solib_events) (sync_execution, sched_multi, step_stop_if_no_debug, non_stop) (disable_randomization, enum exec_direction_kind) (execution_direction, stop_registers, start_remote) (clear_proceed_status, proceed, resume, user_visible_resume_ptid) (wait_for_inferior, normal_stop, get_last_target_status) (prepare_for_detach, fetch_inferior_event, init_wait_for_inferior) (insert_step_resume_breakpoint_at_sal) (follow_inferior_reset_breakpoints, stepping_past_instruction_at) (set_step_info, print_stop_event, signal_stop_state) (signal_print_state, signal_pass_state, signal_stop_update) (signal_print_update, signal_pass_update) (update_signals_program_target, clear_exit_convenience_vars) (displaced_step_dump_bytes, update_observer_mode) (signal_catch_update, gdb_signal_from_command): Move declarations ... * infrun.h: ... to this new file. * amd64-tdep.c: Include infrun.h. * annotate.c: Include infrun.h. * arch-utils.c: Include infrun.h. * arm-linux-tdep.c: Include infrun.h. * arm-tdep.c: Include infrun.h. * break-catch-sig.c: Include infrun.h. * breakpoint.c: Include infrun.h. * common/agent.c: Include infrun.h instead of inferior.h. * corelow.c: Include infrun.h. * event-top.c: Include infrun.h. * go32-nat.c: Include infrun.h. * i386-tdep.c: Include infrun.h. * inf-loop.c: Include infrun.h. * infcall.c: Include infrun.h. * infcmd.c: Include infrun.h. * infrun.c: Include infrun.h. * linux-fork.c: Include infrun.h. * linux-nat.c: Include infrun.h. * linux-thread-db.c: Include infrun.h. * monitor.c: Include infrun.h. * nto-tdep.c: Include infrun.h. * procfs.c: Include infrun.h. * record-btrace.c: Include infrun.h. * record-full.c: Include infrun.h. * remote-m32r-sdi.c: Include infrun.h. * remote-mips.c: Include infrun.h. * remote-notif.c: Include infrun.h. * remote-sim.c: Include infrun.h. * remote.c: Include infrun.h. * reverse.c: Include infrun.h. * rs6000-tdep.c: Include infrun.h. * s390-linux-tdep.c: Include infrun.h. * solib-irix.c: Include infrun.h. * solib-osf.c: Include infrun.h. * solib-svr4.c: Include infrun.h. * target.c: Include infrun.h. * top.c: Include infrun.h. * windows-nat.c: Include infrun.h. * mi/mi-interp.c: Include infrun.h. * mi/mi-main.c: Include infrun.h. * python/py-threadevent.c: Include infrun.h.
2014-05-22 13:29:11 +02:00
/* The `resume' routine should only be called in special circumstances.
Normally, use `proceed', which handles a lot of bookkeeping. */
Remove 'step' parameters from 'proceed' and 'resume' The "step" parameters of 'proceed' and 'resume' aren't really useful as indication of whether run control wants to single-step the target, as that information must already be retrievable from currently_stepping. In fact, if currently_stepping disagrees with whether we single-stepped the target, then things break. Thus instead of having the same information in two places, this patch removes those parameters. Setting 'step_start_function' is the only user of proceed's 'step' argument, other than passing the 'step' argument down to 'resume' and debug log output. Move that instead to set_step_frame, where we already set other related fields. clear_proceed_status keeps its "step" parameter for now because it needs to know which set of threads should have their state cleared, and is called before the "stepping_command" flag is set. Tested on x86_64 Fedora 20, native and gdbserver. gdb/ChangeLog: 2015-03-24 Pedro Alves <palves@redhat.com> * breakpoint.c (until_break_command): Adjust call to proceed. * gdbthread.h (struct thread_control_state) <stepping_command>: New field. * infcall.c (run_inferior_call): Adjust call to proceed. * infcmd.c (run_command_1, proceed_thread_callback, continue_1): Adjust calls to proceed. (set_step_frame): Set the current thread's step_start_function here. (step_once): Adjust calls to proceed. (jump_command, signal_command, until_next_command) (finish_backward, finish_forward, proceed_after_attach_callback) (attach_command_post_wait): Adjust calls to proceed. * infrun.c (proceed_after_vfork_done): Adjust call to proceed. (do_target_resume): New function, factored out from ... (resume): ... here. Remove 'step' parameter. Instead, check currently_stepping to determine whether the thread should be single-stepped. (proceed): Remove 'step' parameter and don't set the thread's step_start_function here. Adjust call to 'resume'. (handle_inferior_event): Adjust calls to 'resume'. (switch_back_to_stepped_thread): Use do_target_resume instead of 'resume'. (keep_going): Adjust calls to 'resume'. * infrun.h (proceed): Remove 'step' parameter. (resume): Likewise. * windows-nat.c (do_initial_windows_stuff): Adjust call to 'resume'. * mi/mi-main.c (proceed_thread): Adjust call to 'proceed'.
2015-03-24 18:50:31 +01:00
extern void resume (enum gdb_signal);
Add new infrun.h header. Move infrun.c declarations out of inferior.h to a new infrun.h file. Tested by building on: i686-w64-mingw32, enable-targets=all x86_64-linux, enable-targets=all i586-pc-msdosdjgpp And also grepped the whole tree for each symbol moved to find where infrun.h might be necessary. gdb/ 2014-05-22 Pedro Alves <palves@redhat.com> * inferior.h (debug_infrun, debug_displaced, stop_on_solib_events) (sync_execution, sched_multi, step_stop_if_no_debug, non_stop) (disable_randomization, enum exec_direction_kind) (execution_direction, stop_registers, start_remote) (clear_proceed_status, proceed, resume, user_visible_resume_ptid) (wait_for_inferior, normal_stop, get_last_target_status) (prepare_for_detach, fetch_inferior_event, init_wait_for_inferior) (insert_step_resume_breakpoint_at_sal) (follow_inferior_reset_breakpoints, stepping_past_instruction_at) (set_step_info, print_stop_event, signal_stop_state) (signal_print_state, signal_pass_state, signal_stop_update) (signal_print_update, signal_pass_update) (update_signals_program_target, clear_exit_convenience_vars) (displaced_step_dump_bytes, update_observer_mode) (signal_catch_update, gdb_signal_from_command): Move declarations ... * infrun.h: ... to this new file. * amd64-tdep.c: Include infrun.h. * annotate.c: Include infrun.h. * arch-utils.c: Include infrun.h. * arm-linux-tdep.c: Include infrun.h. * arm-tdep.c: Include infrun.h. * break-catch-sig.c: Include infrun.h. * breakpoint.c: Include infrun.h. * common/agent.c: Include infrun.h instead of inferior.h. * corelow.c: Include infrun.h. * event-top.c: Include infrun.h. * go32-nat.c: Include infrun.h. * i386-tdep.c: Include infrun.h. * inf-loop.c: Include infrun.h. * infcall.c: Include infrun.h. * infcmd.c: Include infrun.h. * infrun.c: Include infrun.h. * linux-fork.c: Include infrun.h. * linux-nat.c: Include infrun.h. * linux-thread-db.c: Include infrun.h. * monitor.c: Include infrun.h. * nto-tdep.c: Include infrun.h. * procfs.c: Include infrun.h. * record-btrace.c: Include infrun.h. * record-full.c: Include infrun.h. * remote-m32r-sdi.c: Include infrun.h. * remote-mips.c: Include infrun.h. * remote-notif.c: Include infrun.h. * remote-sim.c: Include infrun.h. * remote.c: Include infrun.h. * reverse.c: Include infrun.h. * rs6000-tdep.c: Include infrun.h. * s390-linux-tdep.c: Include infrun.h. * solib-irix.c: Include infrun.h. * solib-osf.c: Include infrun.h. * solib-svr4.c: Include infrun.h. * target.c: Include infrun.h. * top.c: Include infrun.h. * windows-nat.c: Include infrun.h. * mi/mi-interp.c: Include infrun.h. * mi/mi-main.c: Include infrun.h. * python/py-threadevent.c: Include infrun.h.
2014-05-22 13:29:11 +02:00
Always pass signals to the right thread Currently, GDB can pass a signal to the wrong thread in several different but related scenarios. E.g., if thread 1 stops for signal SIGFOO, the user switches to thread 2, and then issues "continue", SIGFOO is actually delivered to thread 2, not thread 1. This obviously messes up programs that use pthread_kill to send signals to specific threads. This has been a known issue for a long while. Back in 2008 when I made stop_signal be per-thread (2020b7ab), I kept the behavior -- see code in 'proceed' being removed -- wanting to come back to it later. The time has finally come now. The patch fixes this -- on resumption, intercepted signals are always delivered to the thread that had intercepted them. Another example: if thread 1 stops for a breakpoint, the user switches to thread 2, and then issues "signal SIGFOO", SIGFOO is actually delivered to thread 1, not thread 2, because 'proceed' first switches to thread 1 to step over its breakpoint... If the user deletes the breakpoint before issuing "signal FOO", then the signal is delivered to thread 2 (the current thread). "signal SIGFOO" can be used for two things: inject a signal in the program while the program/thread had stopped for none, bypassing "handle nopass"; or changing/suppressing a signal the program had stopped for. These scenarios are really two faces of the same coin, and GDB can't really guess what the user is trying to do. GDB might have intercepted signals in more than one thread even (see the new signal-command-multiple-signals-pending.exp test). At least in the inject case, it's obviously clear to me that the user means to deliver the signal to the currently selected thread, so best is to make the command's behavior consistent and easy to explain. Then, if the user is trying to suppress/change a signal the program had stopped for instead of injecting a new signal, but, the user had changed threads meanwhile, then she will be surprised that with: (gdb) continue Thread 1 stopped for signal SIGFOO. (gdb) thread 2 (gdb) signal SIGBAR ... GDB actually delivers SIGFOO to thread 1, and SIGBAR to thread 2 (with scheduler-locking off, which is the default, because then "signal" or any other resumption command resumes all threads). So the patch makes GDB detect that, and ask for confirmation: (gdb) thread 1 [Switching to thread 1 (Thread 10979)] (gdb) signal SIGUSR2 Note: Thread 3 previously stopped with signal SIGUSR2, User defined signal 2. Thread 2 previously stopped with signal SIGUSR1, User defined signal 1. Continuing thread 1 (the current thread) with specified signal will still deliver the signals noted above to their respective threads. Continue anyway? (y or n) All these scenarios are covered by the new tests. Tested on x86_64 Fedora 20, native and gdbserver. gdb/ 2014-07-25 Pedro Alves <palves@redhat.com> * NEWS: Mention signal passing and "signal" command changes. * gdbthread.h (struct thread_suspend_state) <stop_signal>: Extend comment. * breakpoint.c (until_break_command): Adjust clear_proceed_status call. * infcall.c (run_inferior_call): Adjust clear_proceed_status call. * infcmd.c (proceed_thread_callback, continue_1, step_once) (jump_command): Adjust clear_proceed_status call. (signal_command): Warn if other thread that are resumed have signals that will be delivered. Adjust clear_proceed_status call. (until_next_command, finish_command) (proceed_after_attach_callback, attach_command_post_wait) (attach_command): Adjust clear_proceed_status call. * infrun.c (proceed_after_vfork_done): Likewise. (proceed_after_attach_callback): Adjust comment. (clear_proceed_status_thread): Clear stop_signal if not in pass state. (clear_proceed_status_callback): Delete. (clear_proceed_status): New 'step' parameter. Only clear the proceed status of threads the command being prepared is about to resume. (proceed): If passed in an explicit signal, override stop_signal with it. Don't pass the last stop signal to the thread we're resuming. (init_wait_for_inferior): Adjust clear_proceed_status call. (switch_back_to_stepped_thread): Clear the signal if it should not be passed. * infrun.h (clear_proceed_status): New 'step' parameter. (user_visible_resume_ptid): Add comment. * linux-nat.c (linux_nat_resume_callback): Don't check whether the signal is in pass state. * remote.c (append_pending_thread_resumptions): Likewise. * mi/mi-main.c (proceed_thread): Adjust clear_proceed_status call. gdb/doc/ 2014-07-25 Pedro Alves <palves@redhat.com> Eli Zaretskii <eliz@gnu.org> * gdb.texinfo (Signaling) <signal command>: Explain what happens with multi-threaded programs. gdb/testsuite/ 2014-07-25 Pedro Alves <palves@redhat.com> * gdb.threads/signal-command-handle-nopass.c: New file. * gdb.threads/signal-command-handle-nopass.exp: New file. * gdb.threads/signal-command-multiple-signals-pending.c: New file. * gdb.threads/signal-command-multiple-signals-pending.exp: New file. * gdb.threads/signal-delivered-right-thread.c: New file. * gdb.threads/signal-delivered-right-thread.exp: New file.
2014-07-25 17:57:31 +02:00
/* Return a ptid representing the set of threads that we will proceed,
in the perspective of the user/frontend. We may actually resume
fewer threads at first, e.g., if a thread is stopped at a
breakpoint that needs stepping-off, but that should not be visible
to the user/frontend, and neither should the frontend/user be
allowed to proceed any of the threads that happen to be stopped for
internal run control handling, if a previous command wanted them
resumed. */
Add new infrun.h header. Move infrun.c declarations out of inferior.h to a new infrun.h file. Tested by building on: i686-w64-mingw32, enable-targets=all x86_64-linux, enable-targets=all i586-pc-msdosdjgpp And also grepped the whole tree for each symbol moved to find where infrun.h might be necessary. gdb/ 2014-05-22 Pedro Alves <palves@redhat.com> * inferior.h (debug_infrun, debug_displaced, stop_on_solib_events) (sync_execution, sched_multi, step_stop_if_no_debug, non_stop) (disable_randomization, enum exec_direction_kind) (execution_direction, stop_registers, start_remote) (clear_proceed_status, proceed, resume, user_visible_resume_ptid) (wait_for_inferior, normal_stop, get_last_target_status) (prepare_for_detach, fetch_inferior_event, init_wait_for_inferior) (insert_step_resume_breakpoint_at_sal) (follow_inferior_reset_breakpoints, stepping_past_instruction_at) (set_step_info, print_stop_event, signal_stop_state) (signal_print_state, signal_pass_state, signal_stop_update) (signal_print_update, signal_pass_update) (update_signals_program_target, clear_exit_convenience_vars) (displaced_step_dump_bytes, update_observer_mode) (signal_catch_update, gdb_signal_from_command): Move declarations ... * infrun.h: ... to this new file. * amd64-tdep.c: Include infrun.h. * annotate.c: Include infrun.h. * arch-utils.c: Include infrun.h. * arm-linux-tdep.c: Include infrun.h. * arm-tdep.c: Include infrun.h. * break-catch-sig.c: Include infrun.h. * breakpoint.c: Include infrun.h. * common/agent.c: Include infrun.h instead of inferior.h. * corelow.c: Include infrun.h. * event-top.c: Include infrun.h. * go32-nat.c: Include infrun.h. * i386-tdep.c: Include infrun.h. * inf-loop.c: Include infrun.h. * infcall.c: Include infrun.h. * infcmd.c: Include infrun.h. * infrun.c: Include infrun.h. * linux-fork.c: Include infrun.h. * linux-nat.c: Include infrun.h. * linux-thread-db.c: Include infrun.h. * monitor.c: Include infrun.h. * nto-tdep.c: Include infrun.h. * procfs.c: Include infrun.h. * record-btrace.c: Include infrun.h. * record-full.c: Include infrun.h. * remote-m32r-sdi.c: Include infrun.h. * remote-mips.c: Include infrun.h. * remote-notif.c: Include infrun.h. * remote-sim.c: Include infrun.h. * remote.c: Include infrun.h. * reverse.c: Include infrun.h. * rs6000-tdep.c: Include infrun.h. * s390-linux-tdep.c: Include infrun.h. * solib-irix.c: Include infrun.h. * solib-osf.c: Include infrun.h. * solib-svr4.c: Include infrun.h. * target.c: Include infrun.h. * top.c: Include infrun.h. * windows-nat.c: Include infrun.h. * mi/mi-interp.c: Include infrun.h. * mi/mi-main.c: Include infrun.h. * python/py-threadevent.c: Include infrun.h.
2014-05-22 13:29:11 +02:00
extern ptid_t user_visible_resume_ptid (int step);
extern void wait_for_inferior (void);
extern void normal_stop (void);
extern void get_last_target_status (ptid_t *ptid,
struct target_waitstatus *status);
extern void prepare_for_detach (void);
extern void fetch_inferior_event (void *);
extern void init_wait_for_inferior (void);
extern void insert_step_resume_breakpoint_at_sal (struct gdbarch *,
struct symtab_and_line ,
struct frame_id);
/* Returns true if we're trying to step past the instruction at
ADDRESS in ASPACE. */
extern int stepping_past_instruction_at (struct address_space *aspace,
CORE_ADDR address);
Rewrite non-continuable watchpoints handling When GDB finds out the target triggered a watchpoint, and the target has non-continuable watchpoints, GDB sets things up to step past the instruction that triggered the watchpoint. This is just like stepping past a breakpoint, but goes through a different mechanism - it resumes only the thread that needs to step past the watchpoint, but also switches a "infwait state" global, that has the effect that the next target_wait only wait for events only from that thread. This forcing of a ptid to pass to target_wait obviously becomes a bottleneck if we ever support stepping past different watchpoints simultaneously (in separate processes). It's also unnecessary -- the target should only return events for threads that have been resumed; if no other thread than the one we're stepping past the watchpoint has been resumed, then those other threads should not report events. If we couldn't assume that, then stepping past regular breakpoints would be broken for not likewise forcing a similar infwait_state. So this patch eliminates infwait_state, and instead teaches keep_going to mark step_over_info in a way that has the breakpoints module skip inserting watchpoints (because we're stepping past one), like it skips breakpoints when we're stepping past one. Tested on: - x86_64 Fedora 20 (continuable watchpoints) - PPC64 Fedora 18 (non-steppable watchpoints) gdb/ 2014-10-15 Pedro Alves <palves@redhat.com> * breakpoint.c (should_be_inserted): Don't insert watchpoints if trying to step past a non-steppable watchpoint. * gdbthread.h (struct thread_info) <stepping_over_watchpoint>: New field. * infrun.c (struct step_over_info): Add new field 'nonsteppable_watchpoint_p' and adjust comments. (set_step_over_info): New 'nonsteppable_watchpoint_p' parameter. Adjust. (clear_step_over_info): Clear nonsteppable_watchpoint_p as well. (stepping_past_nonsteppable_watchpoint): New function. (step_over_info_valid_p): Also return true if stepping past a nonsteppable watchpoint. (proceed): Adjust call to set_step_over_info. Remove reference to init_infwait_state. (init_wait_for_inferior): Remove reference to init_infwait_state. (waiton_ptid): Delete global. (struct execution_control_state) <stepped_after_stopped_by_watchpoint>: Delete field. (wait_for_inferior, fetch_inferior_event): Always pass minus_one_ptid to target_wait. (init_thread_stepping_state): Clear 'stepping_over_watchpoint' field. (init_infwait_state): Delete function. (handle_inferior_event): Remove infwait_state handling. (handle_signal_stop) <watchpoints handling>: Adjust after stepped_after_stopped_by_watchpoint removal. Don't remove breakpoints here nor set infwait_state. Set the thread's stepping_over_watchpoint flag, and call keep_going instead. (keep_going): Handle stepping_over_watchpoint. Adjust set_step_over_info calls. * infrun.h (stepping_past_nonsteppable_watchpoint): Declare function.
2014-10-15 21:18:30 +02:00
/* Returns true if we're trying to step past an instruction that
triggers a non-steppable watchpoint. */
extern int stepping_past_nonsteppable_watchpoint (void);
Add new infrun.h header. Move infrun.c declarations out of inferior.h to a new infrun.h file. Tested by building on: i686-w64-mingw32, enable-targets=all x86_64-linux, enable-targets=all i586-pc-msdosdjgpp And also grepped the whole tree for each symbol moved to find where infrun.h might be necessary. gdb/ 2014-05-22 Pedro Alves <palves@redhat.com> * inferior.h (debug_infrun, debug_displaced, stop_on_solib_events) (sync_execution, sched_multi, step_stop_if_no_debug, non_stop) (disable_randomization, enum exec_direction_kind) (execution_direction, stop_registers, start_remote) (clear_proceed_status, proceed, resume, user_visible_resume_ptid) (wait_for_inferior, normal_stop, get_last_target_status) (prepare_for_detach, fetch_inferior_event, init_wait_for_inferior) (insert_step_resume_breakpoint_at_sal) (follow_inferior_reset_breakpoints, stepping_past_instruction_at) (set_step_info, print_stop_event, signal_stop_state) (signal_print_state, signal_pass_state, signal_stop_update) (signal_print_update, signal_pass_update) (update_signals_program_target, clear_exit_convenience_vars) (displaced_step_dump_bytes, update_observer_mode) (signal_catch_update, gdb_signal_from_command): Move declarations ... * infrun.h: ... to this new file. * amd64-tdep.c: Include infrun.h. * annotate.c: Include infrun.h. * arch-utils.c: Include infrun.h. * arm-linux-tdep.c: Include infrun.h. * arm-tdep.c: Include infrun.h. * break-catch-sig.c: Include infrun.h. * breakpoint.c: Include infrun.h. * common/agent.c: Include infrun.h instead of inferior.h. * corelow.c: Include infrun.h. * event-top.c: Include infrun.h. * go32-nat.c: Include infrun.h. * i386-tdep.c: Include infrun.h. * inf-loop.c: Include infrun.h. * infcall.c: Include infrun.h. * infcmd.c: Include infrun.h. * infrun.c: Include infrun.h. * linux-fork.c: Include infrun.h. * linux-nat.c: Include infrun.h. * linux-thread-db.c: Include infrun.h. * monitor.c: Include infrun.h. * nto-tdep.c: Include infrun.h. * procfs.c: Include infrun.h. * record-btrace.c: Include infrun.h. * record-full.c: Include infrun.h. * remote-m32r-sdi.c: Include infrun.h. * remote-mips.c: Include infrun.h. * remote-notif.c: Include infrun.h. * remote-sim.c: Include infrun.h. * remote.c: Include infrun.h. * reverse.c: Include infrun.h. * rs6000-tdep.c: Include infrun.h. * s390-linux-tdep.c: Include infrun.h. * solib-irix.c: Include infrun.h. * solib-osf.c: Include infrun.h. * solib-svr4.c: Include infrun.h. * target.c: Include infrun.h. * top.c: Include infrun.h. * windows-nat.c: Include infrun.h. * mi/mi-interp.c: Include infrun.h. * mi/mi-main.c: Include infrun.h. * python/py-threadevent.c: Include infrun.h.
2014-05-22 13:29:11 +02:00
extern void set_step_info (struct frame_info *frame,
struct symtab_and_line sal);
PR gdb/13860 - Make MI sync vs async output (closer to) the same. Ignoring expected and desired differences like whether the prompt is output after *stoppped records, GDB MI output is still different in sync and async modes. In sync mode, when a CLI execution command is entered, the "reason" field is missing in the *stopped async record. And in async mode, for some events, like program exits, the corresponding CLI output is missing in the CLI channel. Vis, diff between sync vs async modes: run ^running *running,thread-id="1" (gdb) ... - ~"[Inferior 1 (process 15882) exited normally]\n" =thread-exited,id="1",group-id="i1" =thread-group-exited,id="i1",exit-code="0" - *stopped + *stopped,reason="exited-normally" si ... (gdb) ~"0x000000000045e033\t29\t memset (&args, 0, sizeof args);\n" - *stopped,frame=...,thread-id="1",stopped-threads="all",core="0" + *stopped,reason="end-stepping-range",frame=...,thread-id="1",stopped-threads="all",core="0" (gdb) In addition, in both cases, when a MI execution command is entered, and a breakpoint triggers, the event is sent to the console too. But some events like program exits have the CLI output missing in the CLI channel: -exec-run ^running *running,thread-id="1" (gdb) ... =thread-exited,id="1",group-id="i1" =thread-group-exited,id="i1",exit-code="0" - *stopped + *stopped,reason="exited-normally" We'll want to make background commands always possible by default. IOW, make target-async be the default. But, in order to do that, we'll need to emulate MI sync on top of an async target. That means we'll have yet another combination to care for in the testsuite. Rather than making the testsuite cope with all these differences, I thought it better to just fix GDB to always have the complete output, no matter whether it's in sync or async mode. This is all related to interpreter-exec, and the corresponding uiout switching. (Typing a CLI command directly in MI is shorthand for running it through -interpreter-exec console.) In sync mode, when a CLI command is active, normal_stop is called when the current interpreter and uiout are CLI's. So print_XXX_reason prints the stop reason to CLI uiout (only), and we don't show it in MI. In async mode the stop event is processed when we're back in the MI interpreter, so the stop reason is printed directly to the MI uiout. Fix this by making run control event printing roughly independent of whatever is the current interpreter or uiout. That is, move these prints to interpreter observers, that know whether to print or be quiet, and if printing, which uiout to print to. In the case of the console/tui interpreters, only print if the top interpreter. For MI, always print. Breakpoint hits / normal stops are already handled similarly -- MI has a normal_stop observer that prints the event to both MI and the CLI, though that could be cleaned up further in the direction of this patch. This also makes all of: (gdb) foo and (gdb) interpreter-exec MI "-exec-foo" and (gdb) -exec-foo and (gdb) -interpreter-exec console "foo" print as expected. Tested on x86_64 Fedora 20, sync and async modes. gdb/ 2014-05-29 Pedro Alves <palves@redhat.com> PR gdb/13860 * cli/cli-interp.c: Include infrun.h and observer.h. (cli_uiout, cli_interp): New globals. (cli_on_signal_received, cli_on_end_stepping_range) (cli_on_signal_exited, cli_on_exited, cli_on_no_history): New functions. (cli_interpreter_init): Install them as 'end_stepping_range', 'signal_received' 'signal_exited', 'exited' and 'no_history' observers. (_initialize_cli_interp): Remove cli_interp local. * infrun.c (handle_inferior_event): Call the several stop reason observers instead of printing the stop reason directly. (end_stepping_range): New function. (print_end_stepping_range_reason, print_signal_exited_reason) (print_exited_reason, print_signal_received_reason) (print_no_history_reason): Make static, and add an uiout parameter. Print to that instead of to CURRENT_UIOUT. * infrun.h (print_end_stepping_range_reason) (print_signal_exited_reason, print_exited_reason) (print_signal_received_reason print_no_history_reason): New declarations. * mi/mi-common.h (struct mi_interp): Rename 'uiout' field to 'mi_uiout'. <cli_uiout>: New field. * mi/mi-interp.c (mi_interpreter_init): Adjust. Create the new uiout for CLI output. Install 'signal_received', 'end_stepping_range', 'signal_exited', 'exited' and 'no_history' observers. (find_mi_interpreter, mi_interp_data, mi_on_signal_received) (mi_on_end_stepping_range, mi_on_signal_exited, mi_on_exited) (mi_on_no_history): New functions. (ui_out_free_cleanup): Delete function. (mi_on_normal_stop): Don't allocate a new uiout for CLI output, instead use the one already stored in the MI interpreter data. (mi_ui_out): Adjust. * tui/tui-interp.c: Include infrun.h and observer.h. (tui_interp): New global. (tui_on_signal_received, tui_on_end_stepping_range) (tui_on_signal_exited, tui_on_exited) (tui_on_no_history): New functions. (tui_init): Install them as 'end_stepping_range', 'signal_received' 'signal_exited', 'exited' and 'no_history' observers. (_initialize_tui_interp): Delete tui_interp local. gdb/doc/ 2014-05-29 Pedro Alves <palves@redhat.com> PR gdb/13860 * observer.texi (signal_received, end_stepping_range) (signal_exited, exited, no_history): New observer subjects. gdb/testsuite/ 2014-05-29 Pedro Alves <palves@redhat.com> PR gdb/13860 * gdb.mi/mi-cli.exp: Always expect "end-stepping-range" stop reason, even in sync mode.
2014-05-29 14:09:45 +02:00
/* Several print_*_reason helper functions to print why the inferior
has stopped to the passed in UIOUT. */
/* Signal received, print why the inferior has stopped. */
extern void print_signal_received_reason (struct ui_out *uiout,
enum gdb_signal siggnal);
/* Print why the inferior has stopped. We are done with a
step/next/si/ni command, print why the inferior has stopped. */
extern void print_end_stepping_range_reason (struct ui_out *uiout);
/* The inferior was terminated by a signal, print why it stopped. */
extern void print_signal_exited_reason (struct ui_out *uiout,
enum gdb_signal siggnal);
/* The inferior program is finished, print why it stopped. */
extern void print_exited_reason (struct ui_out *uiout, int exitstatus);
/* Reverse execution: target ran out of history info, print why the
inferior has stopped. */
extern void print_no_history_reason (struct ui_out *uiout);
Add new infrun.h header. Move infrun.c declarations out of inferior.h to a new infrun.h file. Tested by building on: i686-w64-mingw32, enable-targets=all x86_64-linux, enable-targets=all i586-pc-msdosdjgpp And also grepped the whole tree for each symbol moved to find where infrun.h might be necessary. gdb/ 2014-05-22 Pedro Alves <palves@redhat.com> * inferior.h (debug_infrun, debug_displaced, stop_on_solib_events) (sync_execution, sched_multi, step_stop_if_no_debug, non_stop) (disable_randomization, enum exec_direction_kind) (execution_direction, stop_registers, start_remote) (clear_proceed_status, proceed, resume, user_visible_resume_ptid) (wait_for_inferior, normal_stop, get_last_target_status) (prepare_for_detach, fetch_inferior_event, init_wait_for_inferior) (insert_step_resume_breakpoint_at_sal) (follow_inferior_reset_breakpoints, stepping_past_instruction_at) (set_step_info, print_stop_event, signal_stop_state) (signal_print_state, signal_pass_state, signal_stop_update) (signal_print_update, signal_pass_update) (update_signals_program_target, clear_exit_convenience_vars) (displaced_step_dump_bytes, update_observer_mode) (signal_catch_update, gdb_signal_from_command): Move declarations ... * infrun.h: ... to this new file. * amd64-tdep.c: Include infrun.h. * annotate.c: Include infrun.h. * arch-utils.c: Include infrun.h. * arm-linux-tdep.c: Include infrun.h. * arm-tdep.c: Include infrun.h. * break-catch-sig.c: Include infrun.h. * breakpoint.c: Include infrun.h. * common/agent.c: Include infrun.h instead of inferior.h. * corelow.c: Include infrun.h. * event-top.c: Include infrun.h. * go32-nat.c: Include infrun.h. * i386-tdep.c: Include infrun.h. * inf-loop.c: Include infrun.h. * infcall.c: Include infrun.h. * infcmd.c: Include infrun.h. * infrun.c: Include infrun.h. * linux-fork.c: Include infrun.h. * linux-nat.c: Include infrun.h. * linux-thread-db.c: Include infrun.h. * monitor.c: Include infrun.h. * nto-tdep.c: Include infrun.h. * procfs.c: Include infrun.h. * record-btrace.c: Include infrun.h. * record-full.c: Include infrun.h. * remote-m32r-sdi.c: Include infrun.h. * remote-mips.c: Include infrun.h. * remote-notif.c: Include infrun.h. * remote-sim.c: Include infrun.h. * remote.c: Include infrun.h. * reverse.c: Include infrun.h. * rs6000-tdep.c: Include infrun.h. * s390-linux-tdep.c: Include infrun.h. * solib-irix.c: Include infrun.h. * solib-osf.c: Include infrun.h. * solib-svr4.c: Include infrun.h. * target.c: Include infrun.h. * top.c: Include infrun.h. * windows-nat.c: Include infrun.h. * mi/mi-interp.c: Include infrun.h. * mi/mi-main.c: Include infrun.h. * python/py-threadevent.c: Include infrun.h.
2014-05-22 13:29:11 +02:00
extern void print_stop_event (struct target_waitstatus *ws);
extern int signal_stop_state (int);
extern int signal_print_state (int);
extern int signal_pass_state (int);
extern int signal_stop_update (int, int);
extern int signal_print_update (int, int);
extern int signal_pass_update (int, int);
extern void update_signals_program_target (void);
/* Clear the convenience variables associated with the exit of the
inferior. Currently, those variables are $_exitcode and
$_exitsignal. */
extern void clear_exit_convenience_vars (void);
/* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
extern void displaced_step_dump_bytes (struct ui_file *file,
const gdb_byte *buf, size_t len);
extern struct displaced_step_closure *get_displaced_step_closure_by_addr
(CORE_ADDR addr);
extern void update_observer_mode (void);
extern void signal_catch_update (const unsigned int *);
/* In some circumstances we allow a command to specify a numeric
signal. The idea is to keep these circumstances limited so that
users (and scripts) develop portable habits. For comparison,
POSIX.2 `kill' requires that 1,2,3,6,9,14, and 15 work (and using a
numeric signal at all is obsolescent. We are slightly more lenient
and allow 1-15 which should match host signal numbers on most
systems. Use of symbolic signal names is strongly encouraged. */
enum gdb_signal gdb_signal_from_command (int num);
Teach non-stop to do in-line step-overs (stop all, step, restart) That is, step past breakpoints by: - pausing all threads - removing breakpoint at PC - single-step - reinsert breakpoint - restart threads similarly to all-stop (with displaced stepping disabled). This allows non-stop to work on targets/architectures without displaced stepping support. That is, it makes displaced stepping an optimization instead of a requirement. For example, in principle, all GNU/Linux ports support non-stop mode at the target_ops level, but not all corresponding gdbarch's implement displaced stepping. This should make non-stop work for all (albeit, not as efficiently). And then there are scenarios where even if the architecture supports displaced stepping, we can't use it, because we e.g., don't find a usable address to use as displaced step scratch pad. It should also fix stepping past watchpoints on targets that have non-continuable watchpoints in non-stop mode (e.g., PPC, untested). Running the instruction out of line in the displaced stepping scratch pad doesn't help that case, as the copied instruction reads/writes the same watched memory... We can fix that too by teaching GDB to only remove the watchpoint from the thread that we want to move past the watchpoint (currently, removing a watchpoint always removes it from all threads), but again, that can be considered an optimization; not all targets would support it. For those familiar with the gdb and gdbserver Linux target_ops backends, the implementation should look similar, except it is done on the core side. When we pause threads, we may find they stop with an interesting event that should be handled later when the thread is re-resumed, thus we store such events in the thread object, and mark the event as pending. We should only consume pending events if the thread is indeed resumed, thus we add a new "resumed" flag to the thread object. At a later stage, we might add new target methods to accelerate some of this, like "pause all threads", with corresponding RSP packets, but we'd still need a fallback method for remote targets that don't support such packets, so, again, that can be deferred as optimization. My _real_ motivation here is making it possible to reimplement all-stop mode on top of the target always working on non-stop mode, so that e.g., we can send RSP packets to a remote target even while the target is running -- can't do that in the all-stop RSP variant, by design). Tested on x86_64 Fedora 20, with and without "set displaced off" forced. The latter forces the new code paths whenever GDB needs to step past a breakpoint. gdb/ChangeLog: 2015-08-07 Pedro Alves <pedro@codesourcery.com> * breakpoint.c (breakpoints_should_be_inserted_now): If any thread has a pending status, return true. * gdbthread.h: Include target/waitstatus.h. (struct thread_suspend_state) <stop_reason, waitstatus_pending_p, stop_pc>: New fields. (struct thread_info) <resumed>: New field. (set_resumed): Declare. * infrun.c: Include "event-loop.h". (infrun_async_inferior_event_token, infrun_is_async): New globals. (infrun_async): New function. (clear_step_over_info): Add debug output. (displaced_step_in_progress_any_inferior): New function. (displaced_step_fixup): New returns int. (start_step_over): Handle in-line step-overs too. Assert the thread is marked resumed. (resume_cleanups): Clear the thread's resumed flag. (resume): Set the thread's resumed flag. Return early if the thread has a pending status. Allow stepping a breakpoint with no signal. (proceed): Adjust to check 'resumed' instead of 'executing'. (clear_proceed_status_thread): If the thread has a pending status, and that status is a finished step, discard the pending status. (clear_proceed_status): Don't clear step_over_info here. (random_pending_event_thread, do_target_wait): New functions. (prepare_for_detach, wait_for_inferior, fetch_inferior_event): Use do_target_wait. (wait_one): New function. (THREAD_STOPPED_BY): New macro. (thread_stopped_by_watchpoint, thread_stopped_by_sw_breakpoint) (thread_stopped_by_hw_breakpoint): New functions. (switch_to_thread_cleanup, save_waitstatus, stop_all_threads): New functions. (handle_inferior_event): Also call set_resumed(false) on all threads implicitly stopped by the event. (restart_threads, resumed_thread_with_pending_status): New functions. (finish_step_over): If we were doing an in-line step-over before, and no longer are after trying to start a new step-over, restart all threads. If we have multiple threads with pending events, save the current event and go through the event loop again. (handle_signal_stop): Return early if finish_step_over returns false. <random signal>: If we get a signal while stepping over a breakpoint in-line in non-stop mode, restart all threads. Clear step_over_info before delivering the signal. (keep_going_stepped_thread): Use internal_error instead of gdb_assert. Mark the thread as resumed. (keep_going_pass_signal): Assert the thread isn't already resumed. If some other thread is doing an in-line step-over, defer the resume. If we just started a new in-line step-over, stop all threads. Don't clear step_over_info. (infrun_async_inferior_event_handler): New function. (_initialize_infrun): Create async event handler with infrun_async_inferior_event_handler as callback. (infrun_async): New declaration. * target.c (target_async): New function. * target.h (target_async): Declare macro and readd as function declaration. * target/waitstatus.h (enum target_stop_reason) <TARGET_STOPPED_BY_SINGLE_STEP>: New value. * thread.c (new_thread): Clear the new waitstatus field. (set_resumed): New function.
2015-08-07 18:24:00 +02:00
/* Enables/disables infrun's async event source in the event loop. */
extern void infrun_async (int enable);
Embed the pending step-over chain in thread_info objects In order to teach non-stop mode to do in-line step-overs (pause all threads, remove breakpoint, single-step, reinsert breakpoint, restart threads), we'll need to be able to queue in-line step over requests, much like we queue displaced stepping (out-of-line) requests. Actually, the queue should be the same -- threads wait for their turn to step past something (breakpoint, watchpoint), doesn't matter what technique we end up using when the step over actually starts. I found that the queue management ends up simpler and more efficient if embedded in the thread objects themselves. This commit converts the existing displaced stepping queue to that. Later patches will make the in-line step-overs code paths use it too. gdb/ChangeLog: 2015-08-07 Pedro Alves <palves@redhat.com> * gdbthread.h (struct thread_info) <step_over_prev, step_over_next>: New fields. (thread_step_over_chain_enqueue, thread_step_over_chain_remove) (thread_step_over_chain_next, thread_is_in_step_over_chain): New declarations. * infrun.c (struct displaced_step_request): Delete. (struct displaced_step_inferior_state) <step_request_queue>: Delete field. (displaced_step_prepare): Assert that trap_expected is set. Use thread_step_over_chain_enqueue. Split starting a new displaced step to ... (start_step_over): ... this new function. (resume): Assert the thread isn't waiting for a step over already. (proceed): Assert the thread isn't waiting for a step over already. (infrun_thread_stop_requested): Adjust to remove threads from the embedded step-over chain. (handle_inferior_event) <fork/vfork>: Call start_step_over after displaced_step_fixup. (handle_signal_stop): Call start_step_over after displaced_step_fixup. * infrun.h (step_over_queue_head): New declaration. * thread.c (step_over_chain_enqueue, step_over_chain_remove) (thread_step_over_chain_next, thread_is_in_step_over_chain) (thread_step_over_chain_enqueue) (thread_step_over_chain_remove): New functions. (delete_thread_1): Remove thread from the step-over chain.
2015-08-07 18:23:57 +02:00
/* The global queue of threads that need to do a step-over operation
to get past e.g., a breakpoint. */
extern struct thread_info *step_over_queue_head;
Add new infrun.h header. Move infrun.c declarations out of inferior.h to a new infrun.h file. Tested by building on: i686-w64-mingw32, enable-targets=all x86_64-linux, enable-targets=all i586-pc-msdosdjgpp And also grepped the whole tree for each symbol moved to find where infrun.h might be necessary. gdb/ 2014-05-22 Pedro Alves <palves@redhat.com> * inferior.h (debug_infrun, debug_displaced, stop_on_solib_events) (sync_execution, sched_multi, step_stop_if_no_debug, non_stop) (disable_randomization, enum exec_direction_kind) (execution_direction, stop_registers, start_remote) (clear_proceed_status, proceed, resume, user_visible_resume_ptid) (wait_for_inferior, normal_stop, get_last_target_status) (prepare_for_detach, fetch_inferior_event, init_wait_for_inferior) (insert_step_resume_breakpoint_at_sal) (follow_inferior_reset_breakpoints, stepping_past_instruction_at) (set_step_info, print_stop_event, signal_stop_state) (signal_print_state, signal_pass_state, signal_stop_update) (signal_print_update, signal_pass_update) (update_signals_program_target, clear_exit_convenience_vars) (displaced_step_dump_bytes, update_observer_mode) (signal_catch_update, gdb_signal_from_command): Move declarations ... * infrun.h: ... to this new file. * amd64-tdep.c: Include infrun.h. * annotate.c: Include infrun.h. * arch-utils.c: Include infrun.h. * arm-linux-tdep.c: Include infrun.h. * arm-tdep.c: Include infrun.h. * break-catch-sig.c: Include infrun.h. * breakpoint.c: Include infrun.h. * common/agent.c: Include infrun.h instead of inferior.h. * corelow.c: Include infrun.h. * event-top.c: Include infrun.h. * go32-nat.c: Include infrun.h. * i386-tdep.c: Include infrun.h. * inf-loop.c: Include infrun.h. * infcall.c: Include infrun.h. * infcmd.c: Include infrun.h. * infrun.c: Include infrun.h. * linux-fork.c: Include infrun.h. * linux-nat.c: Include infrun.h. * linux-thread-db.c: Include infrun.h. * monitor.c: Include infrun.h. * nto-tdep.c: Include infrun.h. * procfs.c: Include infrun.h. * record-btrace.c: Include infrun.h. * record-full.c: Include infrun.h. * remote-m32r-sdi.c: Include infrun.h. * remote-mips.c: Include infrun.h. * remote-notif.c: Include infrun.h. * remote-sim.c: Include infrun.h. * remote.c: Include infrun.h. * reverse.c: Include infrun.h. * rs6000-tdep.c: Include infrun.h. * s390-linux-tdep.c: Include infrun.h. * solib-irix.c: Include infrun.h. * solib-osf.c: Include infrun.h. * solib-svr4.c: Include infrun.h. * target.c: Include infrun.h. * top.c: Include infrun.h. * windows-nat.c: Include infrun.h. * mi/mi-interp.c: Include infrun.h. * mi/mi-main.c: Include infrun.h. * python/py-threadevent.c: Include infrun.h.
2014-05-22 13:29:11 +02:00
#endif /* INFRUN_H */