This partially reverts some parts of the commit:
commit 17417fb0ec
Date: Sat Oct 31 09:01:25 2020 -0400
gdb, gdbsupport: add debug_prefixed_printf, remove boilerplate functions
This commit removed 3 places where some debug flags were being
checked. The result was that debug tracing was being printed
unconditionally.
This commit adds back the 3 flag checks.
gdb/ChangeLog:
* infrun.h (infrun_debug_printf): Add check of debug_infrun flag.
(debug_prefixed_printf): Add check of debug_displaced flag.
* linux-nat.c (linux_nat_debug_printf): Add check of
debug_linux_nat flag.
The *_debug_print_1 functions are all very similar, the only difference
being the subsystem name. Remove them all and make the logging macros
use a new debug_prefixed_printf function directly.
gdb/ChangeLog:
* infrun.c (infrun_debug_printf_1): Remove.
(displaced_debug_printf_1): Remove.
(stop_all_threads): Use debug_prefixed_printf.
* infrun.h (infrun_debug_printf_1): Remove.
(infrun_debug_printf): Use debug_prefixed_printf.
(displaced_debug_printf_1): Remove.
(displaced_debug_printf): Use debug_prefixed_printf.
* linux-nat.c (linux_nat_debug_printf_1): Remove.
(linux_nat_debug_printf): Use debug_prefixed_printf.
gdbsupport/ChangeLog:
* common-debug.cc (debug_prefixed_printf): New.
* common-debug.h (debug_prefixed_printf): New declaration.
* event-loop.cc (event_loop_debug_printf_1): Remove.
* event-loop.h (event_loop_debug_printf_1): Remove.
(event_loop_debug_printf): Use debug_prefixed_printf.
(event_loop_ui_debug_printf): Use debug_prefixed_printf.
Change-Id: Ib323087c7257f0060121d302055c41eb64aa60c6
The following patch needs to output debug prints from gdbsupport code.
Move debug_prefixed_vprintf so that it is possible to use it from
gdbsupport.
gdb/ChangeLog:
* debug.c (debug_prefixed_vprintf): Move to gdbsupport.
* debug.h: Remove.
* infrun.c: Include gdbsupport/common-debug.h.
* linux-nat.c: Likewise.
gdbsupport/ChangeLog:
* common-debug.cc (debug_prefixed_vprintf): Move here.
* common-debug.h (debug_prefixed_vprintf): Move here.
Change-Id: I5170065fc10a7a49c0f1bba67c691decb2cf3bcb
Assign names to event loop file handlers. They will be used in debug
messages when file handlers are invoked.
In GDB, each UI used to get its own unique number, until commit
cbe256847e ("Remove ui::num"). Re-introduce this field, and use it to
make a unique name for the handler.
I'm not too sure what goes on in ser-base.c, all I know is that it's
what is used when debugging remotely. I've just named the main handler
"serial". It would be good to have unique names there too. For instance
when debugging with two different remote connections, we'd ideally want
the handlers to have unique names. I didn't do it in this patch though.
gdb/ChangeLog:
* async-event.c (initialize_async_signal_handlers): Pass name to
add_file_handler
* event-top.c (ui_register_input_event_handler): Likewise.
* linux-nat.c (linux_nat_target::async): Likewise.
* run-on-main-thread.c (_initialize_run_on_main_thread):
Likewise
* ser-base.c (reschedule): Likewise.
(ser_base_async): Likewise.
* tui/tui-io.c: Likewise.
* top.h (struct ui) <num>: New field.
* top.c (highest_ui_num): New variable.
(ui::ui): Initialize num.
gdbserver/ChangeLog:
* linux-low.cc (linux_process_target::async): Pass name to
add_file_handler.
* remote-utils.cc (handle_accept_event): Likewise.
(remote_open): Likewise.
gdbsupport/ChangeLog:
* event-loop.h (add_file_handler): Add "name" parameter.
* event-loop.cc (struct file_handler) <name>: New field.
(create_file_handler): Add "name" parameter, assign it to file
handler.
(add_file_handler): Add "name" parameter.
Change-Id: I9f1545f73888ebb6778eb653a618ca44d105f92c
The do/while in these macros are not formatted with proper GNU style,
fix that.
gdb/ChangeLog:
* infrun.h (infrun_debug_printf): Fix formatting.
* linux-nat.c (linux_nat_debug_printf): Fix formatting.
Change-Id: I3a723663c76d9091f785941923c2b6cf67459629
target_ops::wait implementations should not rely on the value of
inferior_ptid on entry. While looking at another wait-related patch, I
noticed that the code in linux_nat_wait_1, checking for a newly created
process, did just that. This patch fixes it. Note that I didn't see
any bug, this "fix" is simply to make the function respect the
target_ops::wait contract.
Instead of checking inferior_ptid, check for the passed in `ptid`
value.
During startup, linux_nat_wait_1 gets called a few times with the
pid-only ptid, while startup_inferior waits for the expected number of
exec events. For this reason, I needed to add a `find_lwp_pid` call to
ensure that the actions of changing the main thread's ptid, and adding
the initial lwp, were done only once for a given process.
This was not needed before, since thread_change_ptid, through the
thread_ptid_changed observer, ends up changing inferior_ptid. So the
second time around, inferior_ptid was not a pid-only ptid.
That find_lwp_pid won't add much overhead, as it will only be called
when the ptid is a pid-only ptid. And AFAIK, that only happens during
inferior startup.
An alternative to that `find_lwp_pid` call might be to make
startup_inferior realize that the main thread has changed ptid, and make
it wait for the new ptid. But that doesn't look easy to do.
Regtested on amd64/Linux.
gdb/ChangeLog:
* linux-nat.c (linux_nat_wait_1): Don't use inferior_ptid when
checking for initial lwp.
Change-Id: I8f1d5c766f5cb2a29c948bc75fa4582d7130c23f
To help ensure that all debug statements have the same format, introduce
the debug_prefixed_vprintf helper. Implement linux_nat_debug_printf_1
and infrun_debug_printf_1 with it.
I would eventually like to style the module and function name with some
color, to help them stick out, but I don't really know how to do that
yet, it can always be done later.
gdb/ChangeLog:
* debug.h: New file.
* debug.c (debug_prefixed_vprintf): New function.
* infrun.c (infrun_debug_printf_1): Use debug_prefixed_vprintf.
* linux-nat.c (linux_nat_debug_printf_1): Likewise.
Change-Id: Iccc290a2dc6b5fffcbe1c2866ed8d804ad380764
The debug prints inside linux-nat.c almost all have a prefix that
indicate in which function they are located. This prefix is an
abbreviation of the function name. For example, this print is in the
`linux_nat_post_attach_wait` function:
if (debug_linux_nat)
fprintf_unfiltered (gdb_stdlog,
"LNPAW: Attaching to a stopped process\n");
Over time, the code has changed, things were moved, and many of these
prefixes are not accurate anymore. Also, unless you know the
linux-nat.c file by heart, it's a bit cryptic what LLR, LNW, RSRL, etc,
all mean.
To address both of these issues, I suggest adding this macro for
printing debug statements, which automatically includes the function
name. It also includes the `[linux-nat]` prefix to clarify which part
of GDB printed this (I think that, ideally, all debug prints would
include such a tag).
The `__func__` magic symbol is used to get the function name.
Unfortunately, in the case of methods, it only contains the method name,
not the class name. So we'll get "wait", where I would have liked to
get "linux_nat_target::wait". But at least with the `[linux-nat]` tag
in the front, it's not really ambiguous.
I've made the macro automatically include the trailing newline, because
it wouldn't make sense to call it twice to print two parts of one line,
the `[linux-nat]` tag would be printed in the middle.
An advantage of this (IMO) is that it's less verbose, we don't have to
check for `if (debug_linux_nat)` everywhere.
Another advantage is that it's easier to customize the output later,
without having to touch all call sites.
Here's an example of what it looks like in the end:
[linux-nat] linux_nat_wait_1: enter
[linux-nat] wait: [process -1], [TARGET_WNOHANG]
gdb/ChangeLog:
* linux-nat.c (linux_nat_debug_printf): New function.
(linux_nat_debug_printf_1): New macro. Use throughout the file.
Change-Id: Ifcea3255b91400d3ad093cd0b75d3fac241cb998
I noticed that my IDE was confusing the two stopped_pids variables.
There is one in GDB and one in GDBserver. They should be static, make
them so.
gdb/ChangeLog:
* linux-nat.c (stopped_pids): Make static.
gdbserver/ChangeLog:
* linux-low.cc (stopped_pids): Make static.
Change-Id: If4a2bdcd45d32eb3a732d266a0f686a4e4c23672
The "linux_multi_process" is initialized but never modified. I
discussed this with Pedro on irc, and he said that, while it was
useful when developing this feature, it is now no longer needed. So,
this removes it.
gdb/ChangeLog
2020-07-18 Tom Tromey <tom@tromey.com>
* linux-nat.c (linux_multi_process): Remove.
(linux_nat_target::supports_multi_process): Return true.
I noticed a couple of spots in linux-nat.c that use 0/1 where boolean
literals would be more idiomatic. This patch makes this change.
gdb/ChangeLog
2020-07-17 Tom Tromey <tromey@adacore.com>
* linux-nat.c (linux_nat_target::supports_non_stop)
(linux_nat_target::always_non_stop_p): Use "true".
(linux_nat_target::supports_disable_randomization): Use "true" and
"false".
I noticed that fetch_inferior_event receives the client_data parameter
from its caller, inferior_event_handler, but doesn't actually need it.
This patch removes it. In turn, inferior_event_handler doesn't use its
parameter, so remove it too.
The `data` argument used when registering
remote_async_inferior_event_handler is changed to NULL, to avoid
confusion. It could make people think that the value passed is used
somewhere, when in fact it's not.
gdb/ChangeLog:
* inf-loop.c (inferior_event_handler): Remove client_data param.
* inf-loop.h (inferior_event_handler): Likewise.
* infcmd.c (step_1): Adjust.
* infrun.c (proceed): Adjust.
(fetch_inferior_event): Remove client_data param.
(infrun_async_inferior_event_handler): Adjust.
* infrun.h (fetch_inferior_event): Remove `void *` param.
* linux-nat.c (handle_target_event): Adjust.
* record-btrace.c (record_btrace_handle_async_inferior_event):
Adjust.
* record-full.c (record_full_async_inferior_event_handler):
Adjust.
* remote.c (remote_async_inferior_event_handler): Adjust.
Change-Id: I3c2aa1eb0ea3e0985df096660d2dcd794674f2ea
This patch adds a low_new_clone method to linux_nat_target, called after
a PTRACE_EVENT_CLONE is detected, similar to how low_new_fork is called
after PTRACE_EVENT_(V)FORK.
This is useful for targets that need to copy state associated with a
thread that is inherited across clones.
gdb/ChangeLog:
2020-03-30 Pedro Franco de Carvalho <pedromfc@linux.ibm.com>
* linux-nat.h (low_new_clone): New method.
* linux-nat.c (linux_handle_extended_wait): Call low_new_clone.
While doing some investigation of mine, i noticed a few typos,
inaccuracies and missing information.
I went ahead and updated/improved those.
gdb/ChangeLog:
2020-01-14 Luis Machado <luis.machado@linaro.org>
* inf-ptrace.c (inf_ptrace_target::resume): Update comments.
* infrun.c (resume_1): Likewise.
(handle_inferior_event): Remove stale comment.
* linux-nat.c (linux_nat_target::resume): Update comments.
(save_stop_reason): Likewise.
(linux_nat_filter_event): Likewise.
* linux-nat.h (struct lwp_info) <stop_pc>, <stop_reason>: Likewise.
This commit adds multi-target support to GDB. What this means is that
with this commit, GDB can now be connected to different targets at the
same time. E.g., you can debug a live native process and a core dump
at the same time, connect to multiple gdbservers, etc.
Actually, the word "target" is overloaded in gdb. We already have a
target stack, with pushes several target_ops instances on top of one
another. We also have "info target" already, which means something
completely different to what this patch does.
So from here on, I'll be using the "target connections" term, to mean
an open process_stratum target, pushed on a target stack. This patch
makes gdb have multiple target stacks, and multiple process_stratum
targets open simultaneously. The user-visible changes / commands will
also use this terminology, but of course it's all open to debate.
User-interface-wise, not that much changes. The main difference is
that each inferior may have its own target connection.
A target connection (e.g., a target extended-remote connection) may
support debugging multiple processes, just as before.
Say you're debugging against gdbserver in extended-remote mode, and
you do "add-inferior" to prepare to spawn a new process, like:
(gdb) target extended-remote :9999
...
(gdb) start
...
(gdb) add-inferior
Added inferior 2
(gdb) inferior 2
[Switching to inferior 2 [<null>] (<noexec>)]
(gdb) file a.out
...
(gdb) start
...
At this point, you have two inferiors connected to the same gdbserver.
With this commit, GDB will maintain a target stack per inferior,
instead of a global target stack.
To preserve the behavior above, by default, "add-inferior" makes the
new inferior inherit a copy of the target stack of the current
inferior. Same across a fork - the child inherits a copy of the
target stack of the parent. While the target stacks are copied, the
targets themselves are not. Instead, target_ops is made a
refcounted_object, which means that target_ops instances are
refcounted, which each inferior counting for a reference.
What if you want to create an inferior and connect it to some _other_
target? For that, this commit introduces a new "add-inferior
-no-connection" option that makes the new inferior not share the
current inferior's target. So you could do:
(gdb) target extended-remote :9999
Remote debugging using :9999
...
(gdb) add-inferior -no-connection
[New inferior 2]
Added inferior 2
(gdb) inferior 2
[Switching to inferior 2 [<null>] (<noexec>)]
(gdb) info inferiors
Num Description Executable
1 process 18401 target:/home/pedro/tmp/main
* 2 <null>
(gdb) tar extended-remote :10000
Remote debugging using :10000
...
(gdb) info inferiors
Num Description Executable
1 process 18401 target:/home/pedro/tmp/main
* 2 process 18450 target:/home/pedro/tmp/main
(gdb)
A following patch will extended "info inferiors" to include a column
indicating which connection an inferior is bound to, along with a
couple other UI tweaks.
Other than that, debugging is the same as before. Users interact with
inferiors and threads as before. The only difference is that
inferiors may be bound to processes running in different machines.
That's pretty much all there is to it in terms of noticeable UI
changes.
On to implementation.
Since we can be connected to different systems at the same time, a
ptid_t is no longer a unique identifier. Instead a thread can be
identified by a pair of ptid_t and 'process_stratum_target *', the
later being the instance of the process_stratum target that owns the
process/thread. Note that process_stratum_target inherits from
target_ops, and all process_stratum targets inherit from
process_stratum_target. In earlier patches, many places in gdb were
converted to refer to threads by thread_info pointer instead of
ptid_t, but there are still places in gdb where we start with a
pid/tid and need to find the corresponding inferior or thread_info
objects. So you'll see in the patch many places adding a
process_stratum_target parameter to functions that used to take only a
ptid_t.
Since each inferior has its own target stack now, we can always find
the process_stratum target for an inferior. That is done via a
inf->process_target() convenience method.
Since each inferior has its own target stack, we need to handle the
"beneath" calls when servicing target calls. The solution I settled
with is just to make sure to switch the current inferior to the
inferior you want before making a target call. Not relying on global
context is just not feasible in current GDB. Fortunately, there
aren't that many places that need to do that, because generally most
code that calls target methods already has the current context
pointing to the right inferior/thread. Note, to emphasize -- there's
no method to "switch to this target stack". Instead, you switch the
current inferior, and that implicitly switches the target stack.
In some spots, we need to iterate over all inferiors so that we reach
all target stacks.
Native targets are still singletons. There's always only a single
instance of such targets.
Remote targets however, we'll have one instance per remote connection.
The exec target is still a singleton. There's only one instance. I
did not see the point of instanciating more than one exec_target
object.
After vfork, we need to make sure to push the exec target on the new
inferior. See exec_on_vfork.
For type safety, functions that need a {target, ptid} pair to identify
a thread, take a process_stratum_target pointer for target parameter
instead of target_ops *. Some shared code in gdb/nat/ also need to
gain a target pointer parameter. This poses an issue, since gdbserver
doesn't have process_stratum_target, only target_ops. To fix this,
this commit renames gdbserver's target_ops to process_stratum_target.
I think this makes sense. There's no concept of target stack in
gdbserver, and gdbserver's target_ops really implements a
process_stratum-like target.
The thread and inferior iterator functions also gain
process_stratum_target parameters. These are used to be able to
iterate over threads and inferiors of a given target. Following usual
conventions, if the target pointer is null, then we iterate over
threads and inferiors of all targets.
I tried converting "add-inferior" to the gdb::option framework, as a
preparatory patch, but that stumbled on the fact that gdb::option does
not support file options yet, for "add-inferior -exec". I have a WIP
patchset that adds that, but it's not a trivial patch, mainly due to
need to integrate readline's filename completion, so I deferred that
to some other time.
In infrun.c/infcmd.c, the main change is that we need to poll events
out of all targets. See do_target_wait. Right after collecting an
event, we switch the current inferior to an inferior bound to the
target that reported the event, so that target methods can be used
while handling the event. This makes most of the code transparent to
multi-targets. See fetch_inferior_event.
infrun.c:stop_all_threads is interesting -- in this function we need
to stop all threads of all targets. What the function does is send an
asynchronous stop request to all threads, and then synchronously waits
for events, with target_wait, rinse repeat, until all it finds are
stopped threads. Now that we have multiple targets, it's not
efficient to synchronously block in target_wait waiting for events out
of one target. Instead, we implement a mini event loop, with
interruptible_select, select'ing on one file descriptor per target.
For this to work, we need to be able to ask the target for a waitable
file descriptor. Such file descriptors already exist, they are the
descriptors registered in the main event loop with add_file_handler,
inside the target_async implementations. This commit adds a new
target_async_wait_fd target method that just returns the file
descriptor in question. See wait_one / stop_all_threads in infrun.c.
The 'threads_executing' global is made a per-target variable. Since
it is only relevant to process_stratum_target targets, this is where
it is put, instead of in target_ops.
You'll notice that remote.c includes some FIXME notes. These refer to
the fact that the global arrays that hold data for the remote packets
supported are still globals. For example, if we connect to two
different servers/stubs, then each might support different remote
protocol features. They might even be different architectures, like
e.g., one ARM baremetal stub, and a x86 gdbserver, to debug a
host/controller scenario as a single program. That isn't going to
work correctly today, because of said globals. I'm leaving fixing
that for another pass, since it does not appear to be trivial, and I'd
rather land the base work first. It's already useful to be able to
debug multiple instances of the same server (e.g., a distributed
cluster, where you have full control over the servers installed), so I
think as is it's already reasonable incremental progress.
Current limitations:
- You can only resume more that one target at the same time if all
targets support asynchronous debugging, and support non-stop mode.
It should be possible to support mixed all-stop + non-stop
backends, but that is left for another time. This means that
currently in order to do multi-target with gdbserver you need to
issue "maint set target-non-stop on". I would like to make that
mode be the default, but we're not there yet. Note that I'm
talking about how the target backend works, only. User-visible
all-stop mode works just fine.
- As explained above, connecting to different remote servers at the
same time is likely to produce bad results if they don't support the
exact set of RSP features.
FreeBSD updates courtesy of John Baldwin.
gdb/ChangeLog:
2020-01-10 Pedro Alves <palves@redhat.com>
John Baldwin <jhb@FreeBSD.org>
* aarch64-linux-nat.c
(aarch64_linux_nat_target::thread_architecture): Adjust.
* ada-tasks.c (print_ada_task_info): Adjust find_thread_ptid call.
(task_command_1): Likewise.
* aix-thread.c (sync_threadlists, aix_thread_target::resume)
(aix_thread_target::wait, aix_thread_target::fetch_registers)
(aix_thread_target::store_registers)
(aix_thread_target::thread_alive): Adjust.
* amd64-fbsd-tdep.c: Include "inferior.h".
(amd64fbsd_get_thread_local_address): Pass down target.
* amd64-linux-nat.c (ps_get_thread_area): Use ps_prochandle
thread's gdbarch instead of target_gdbarch.
* break-catch-sig.c (signal_catchpoint_print_it): Adjust call to
get_last_target_status.
* break-catch-syscall.c (print_it_catch_syscall): Likewise.
* breakpoint.c (breakpoints_should_be_inserted_now): Consider all
inferiors.
(update_inserted_breakpoint_locations): Skip if inferiors with no
execution.
(update_global_location_list): When handling moribund locations,
find representative inferior for location's pspace, and use thread
count of its process_stratum target.
* bsd-kvm.c (bsd_kvm_target_open): Pass target down.
* bsd-uthread.c (bsd_uthread_target::wait): Use
as_process_stratum_target and adjust thread_change_ptid and
add_thread calls.
(bsd_uthread_target::update_thread_list): Use
as_process_stratum_target and adjust find_thread_ptid,
thread_change_ptid and add_thread calls.
* btrace.c (maint_btrace_packet_history_cmd): Adjust
find_thread_ptid call.
* corelow.c (add_to_thread_list): Adjust add_thread call.
(core_target_open): Adjust add_thread_silent and thread_count
calls.
(core_target::pid_to_str): Adjust find_inferior_ptid call.
* ctf.c (ctf_target_open): Adjust add_thread_silent call.
* event-top.c (async_disconnect): Pop targets from all inferiors.
* exec.c (add_target_sections): Push exec target on all inferiors
sharing the program space.
(remove_target_sections): Remove the exec target from all
inferiors sharing the program space.
(exec_on_vfork): New.
* exec.h (exec_on_vfork): Declare.
* fbsd-nat.c (fbsd_add_threads): Add fbsd_nat_target parameter.
Pass it down.
(fbsd_nat_target::update_thread_list): Adjust.
(fbsd_nat_target::resume): Adjust.
(fbsd_handle_debug_trap): Add fbsd_nat_target parameter. Pass it
down.
(fbsd_nat_target::wait, fbsd_nat_target::post_attach): Adjust.
* fbsd-tdep.c (fbsd_corefile_thread): Adjust
get_thread_arch_regcache call.
* fork-child.c (gdb_startup_inferior): Pass target down to
startup_inferior and set_executing.
* gdbthread.h (struct process_stratum_target): Forward declare.
(add_thread, add_thread_silent, add_thread_with_info)
(in_thread_list): Add process_stratum_target parameter.
(find_thread_ptid(inferior*, ptid_t)): New overload.
(find_thread_ptid, thread_change_ptid): Add process_stratum_target
parameter.
(all_threads()): Delete overload.
(all_threads, all_non_exited_threads): Add process_stratum_target
parameter.
(all_threads_safe): Use brace initialization.
(thread_count): Add process_stratum_target parameter.
(set_resumed, set_running, set_stop_requested, set_executing)
(threads_are_executing, finish_thread_state): Add
process_stratum_target parameter.
(switch_to_thread): Use is_current_thread.
* i386-fbsd-tdep.c: Include "inferior.h".
(i386fbsd_get_thread_local_address): Pass down target.
* i386-linux-nat.c (i386_linux_nat_target::low_resume): Adjust.
* inf-child.c (inf_child_target::maybe_unpush_target): Remove
have_inferiors check.
* inf-ptrace.c (inf_ptrace_target::create_inferior)
(inf_ptrace_target::attach): Adjust.
* infcall.c (run_inferior_call): Adjust.
* infcmd.c (run_command_1): Pass target to
scoped_finish_thread_state.
(proceed_thread_callback): Skip inferiors with no execution.
(continue_command): Rename 'all_threads' local to avoid hiding
'all_threads' function. Adjust get_last_target_status call.
(prepare_one_step): Adjust set_running call.
(signal_command): Use user_visible_resume_target. Compare thread
pointers instead of inferior_ptid.
(info_program_command): Adjust to pass down target.
(attach_command): Mark target's 'thread_executing' flag.
(stop_current_target_threads_ns): New, factored out from ...
(interrupt_target_1): ... this. Switch inferior before making
target calls.
* inferior-iter.h
(struct all_inferiors_iterator, struct all_inferiors_range)
(struct all_inferiors_safe_range)
(struct all_non_exited_inferiors_range): Filter on
process_stratum_target too. Remove explicit.
* inferior.c (inferior::inferior): Push dummy target on target
stack.
(find_inferior_pid, find_inferior_ptid, number_of_live_inferiors):
Add process_stratum_target parameter, and pass it down.
(have_live_inferiors): Adjust.
(switch_to_inferior_and_push_target): New.
(add_inferior_command, clone_inferior_command): Handle
"-no-connection" parameter. Use
switch_to_inferior_and_push_target.
(_initialize_inferior): Mention "-no-connection" option in
the help of "add-inferior" and "clone-inferior" commands.
* inferior.h: Include "process-stratum-target.h".
(interrupt_target_1): Use bool.
(struct inferior) <push_target, unpush_target, target_is_pushed,
find_target_beneath, top_target, process_target, target_at,
m_stack>: New.
(discard_all_inferiors): Delete.
(find_inferior_pid, find_inferior_ptid, number_of_live_inferiors)
(all_inferiors, all_non_exited_inferiors): Add
process_stratum_target parameter.
* infrun.c: Include "gdb_select.h" and <unordered_map>.
(target_last_proc_target): New global.
(follow_fork_inferior): Push target on new inferior. Pass target
to add_thread_silent. Call exec_on_vfork. Handle target's
reference count.
(follow_fork): Adjust get_last_target_status call. Also consider
target.
(follow_exec): Push target on new inferior.
(struct execution_control_state) <target>: New field.
(user_visible_resume_target): New.
(do_target_resume): Call target_async.
(resume_1): Set target's threads_executing flag. Consider resume
target.
(commit_resume_all_targets): New.
(proceed): Also consider resume target. Skip threads of inferiors
with no execution. Commit resumtion in all targets.
(start_remote): Pass current inferior to wait_for_inferior.
(infrun_thread_stop_requested): Consider target as well. Pass
thread_info pointer to clear_inline_frame_state instead of ptid.
(infrun_thread_thread_exit): Consider target as well.
(random_pending_event_thread): New inferior parameter. Use it.
(do_target_wait): Rename to ...
(do_target_wait_1): ... this. Add inferior parameter, and pass it
down.
(threads_are_resumed_pending_p, do_target_wait): New.
(prepare_for_detach): Adjust calls.
(wait_for_inferior): New inferior parameter. Handle it. Use
do_target_wait_1 instead of do_target_wait.
(fetch_inferior_event): Adjust. Switch to representative
inferior. Pass target down.
(set_last_target_status): Add process_stratum_target parameter.
Save target in global.
(get_last_target_status): Add process_stratum_target parameter and
handle it.
(nullify_last_target_wait_ptid): Clear 'target_last_proc_target'.
(context_switch): Check inferior_ptid == null_ptid before calling
inferior_thread().
(get_inferior_stop_soon): Pass down target.
(wait_one): Rename to ...
(poll_one_curr_target): ... this.
(struct wait_one_event): New.
(wait_one): New.
(stop_all_threads): Adjust.
(handle_no_resumed, handle_inferior_event): Adjust to consider the
event's target.
(switch_back_to_stepped_thread): Also consider target.
(print_stop_event): Update.
(normal_stop): Update. Also consider the resume target.
* infrun.h (wait_for_inferior): Remove declaration.
(user_visible_resume_target): New declaration.
(get_last_target_status, set_last_target_status): New
process_stratum_target parameter.
* inline-frame.c (clear_inline_frame_state(ptid_t)): Add
process_stratum_target parameter, and use it.
(clear_inline_frame_state (thread_info*)): New.
* inline-frame.c (clear_inline_frame_state(ptid_t)): Add
process_stratum_target parameter.
(clear_inline_frame_state (thread_info*)): Declare.
* linux-fork.c (delete_checkpoint_command): Pass target down to
find_thread_ptid.
(checkpoint_command): Adjust.
* linux-nat.c (linux_nat_target::follow_fork): Switch to thread
instead of just tweaking inferior_ptid.
(linux_nat_switch_fork): Pass target down to thread_change_ptid.
(exit_lwp): Pass target down to find_thread_ptid.
(attach_proc_task_lwp_callback): Pass target down to
add_thread/set_running/set_executing.
(linux_nat_target::attach): Pass target down to
thread_change_ptid.
(get_detach_signal): Pass target down to find_thread_ptid.
Consider last target status's target.
(linux_resume_one_lwp_throw, resume_lwp)
(linux_handle_syscall_trap, linux_handle_extended_wait, wait_lwp)
(stop_wait_callback, save_stop_reason, linux_nat_filter_event)
(linux_nat_wait_1, resume_stopped_resumed_lwps): Pass target down.
(linux_nat_target::async_wait_fd): New.
(linux_nat_stop_lwp, linux_nat_target::thread_address_space): Pass
target down.
* linux-nat.h (linux_nat_target::async_wait_fd): Declare.
* linux-tdep.c (get_thread_arch_regcache): Pass target down.
* linux-thread-db.c (struct thread_db_info::process_target): New
field.
(add_thread_db_info): Save target.
(get_thread_db_info): New process_stratum_target parameter. Also
match target.
(delete_thread_db_info): New process_stratum_target parameter.
Also match target.
(thread_from_lwp): Adjust to pass down target.
(thread_db_notice_clone): Pass down target.
(check_thread_db_callback): Pass down target.
(try_thread_db_load_1): Always push the thread_db target.
(try_thread_db_load, record_thread): Pass target down.
(thread_db_target::detach): Pass target down. Always unpush the
thread_db target.
(thread_db_target::wait, thread_db_target::mourn_inferior): Pass
target down. Always unpush the thread_db target.
(find_new_threads_callback, thread_db_find_new_threads_2)
(thread_db_target::update_thread_list): Pass target down.
(thread_db_target::pid_to_str): Pass current inferior down.
(thread_db_target::get_thread_local_address): Pass target down.
(thread_db_target::resume, maintenance_check_libthread_db): Pass
target down.
* nto-procfs.c (nto_procfs_target::update_thread_list): Adjust.
* procfs.c (procfs_target::procfs_init_inferior): Declare.
(proc_set_current_signal, do_attach, procfs_target::wait): Adjust.
(procfs_init_inferior): Rename to ...
(procfs_target::procfs_init_inferior): ... this and adjust.
(procfs_target::create_inferior, procfs_notice_thread)
(procfs_do_thread_registers): Adjust.
* ppc-fbsd-tdep.c: Include "inferior.h".
(ppcfbsd_get_thread_local_address): Pass down target.
* proc-service.c (ps_xfer_memory): Switch current inferior and
program space as well.
(get_ps_regcache): Pass target down.
* process-stratum-target.c
(process_stratum_target::thread_address_space)
(process_stratum_target::thread_architecture): Pass target down.
* process-stratum-target.h
(process_stratum_target::threads_executing): New field.
(as_process_stratum_target): New.
* ravenscar-thread.c
(ravenscar_thread_target::update_inferior_ptid): Pass target down.
(ravenscar_thread_target::wait, ravenscar_add_thread): Pass target
down.
* record-btrace.c (record_btrace_target::info_record): Adjust.
(record_btrace_target::record_method)
(record_btrace_target::record_is_replaying)
(record_btrace_target::fetch_registers)
(get_thread_current_frame_id, record_btrace_target::resume)
(record_btrace_target::wait, record_btrace_target::stop): Pass
target down.
* record-full.c (record_full_wait_1): Switch to event thread.
Pass target down.
* regcache.c (regcache::regcache)
(get_thread_arch_aspace_regcache, get_thread_arch_regcache): Add
process_stratum_target parameter and handle it.
(current_thread_target): New global.
(get_thread_regcache): Add process_stratum_target parameter and
handle it. Switch inferior before calling target method.
(get_thread_regcache): Pass target down.
(get_thread_regcache_for_ptid): Pass target down.
(registers_changed_ptid): Add process_stratum_target parameter and
handle it.
(registers_changed_thread, registers_changed): Pass target down.
(test_get_thread_arch_aspace_regcache): New.
(current_regcache_test): Define a couple local test_target_ops
instances and use them for testing.
(readwrite_regcache): Pass process_stratum_target parameter.
(cooked_read_test, cooked_write_test): Pass mock_target down.
* regcache.h (get_thread_regcache, get_thread_arch_regcache)
(get_thread_arch_aspace_regcache): Add process_stratum_target
parameter.
(regcache::target): New method.
(regcache::regcache, regcache::get_thread_arch_aspace_regcache)
(regcache::registers_changed_ptid): Add process_stratum_target
parameter.
(regcache::m_target): New field.
(registers_changed_ptid): Add process_stratum_target parameter.
* remote.c (remote_state::supports_vCont_probed): New field.
(remote_target::async_wait_fd): New method.
(remote_unpush_and_throw): Add remote_target parameter.
(get_current_remote_target): Adjust.
(remote_target::remote_add_inferior): Push target.
(remote_target::remote_add_thread)
(remote_target::remote_notice_new_inferior)
(get_remote_thread_info): Pass target down.
(remote_target::update_thread_list): Skip threads of inferiors
bound to other targets. (remote_target::close): Don't discard
inferiors. (remote_target::add_current_inferior_and_thread)
(remote_target::process_initial_stop_replies)
(remote_target::start_remote)
(remote_target::remote_serial_quit_handler): Pass down target.
(remote_target::remote_unpush_target): New remote_target
parameter. Unpush the target from all inferiors.
(remote_target::remote_unpush_and_throw): New remote_target
parameter. Pass it down.
(remote_target::open_1): Check whether the current inferior has
execution instead of checking whether any inferior is live. Pass
target down.
(remote_target::remote_detach_1): Pass down target. Use
remote_unpush_target.
(extended_remote_target::attach): Pass down target.
(remote_target::remote_vcont_probe): Set supports_vCont_probed.
(remote_target::append_resumption): Pass down target.
(remote_target::append_pending_thread_resumptions)
(remote_target::remote_resume_with_hc, remote_target::resume)
(remote_target::commit_resume): Pass down target.
(remote_target::remote_stop_ns): Check supports_vCont_probed.
(remote_target::interrupt_query)
(remote_target::remove_new_fork_children)
(remote_target::check_pending_events_prevent_wildcard_vcont)
(remote_target::remote_parse_stop_reply)
(remote_target::process_stop_reply): Pass down target.
(first_remote_resumed_thread): New remote_target parameter. Pass
it down.
(remote_target::wait_as): Pass down target.
(unpush_and_perror): New remote_target parameter. Pass it down.
(remote_target::readchar, remote_target::remote_serial_write)
(remote_target::getpkt_or_notif_sane_1)
(remote_target::kill_new_fork_children, remote_target::kill): Pass
down target.
(remote_target::mourn_inferior): Pass down target. Use
remote_unpush_target.
(remote_target::core_of_thread)
(remote_target::remote_btrace_maybe_reopen): Pass down target.
(remote_target::pid_to_exec_file)
(remote_target::thread_handle_to_thread_info): Pass down target.
(remote_target::async_wait_fd): New.
* riscv-fbsd-tdep.c: Include "inferior.h".
(riscv_fbsd_get_thread_local_address): Pass down target.
* sol2-tdep.c (sol2_core_pid_to_str): Pass down target.
* sol-thread.c (sol_thread_target::wait, ps_lgetregs, ps_lsetregs)
(ps_lgetfpregs, ps_lsetfpregs, sol_update_thread_list_callback):
Adjust.
* solib-spu.c (spu_skip_standalone_loader): Pass down target.
* solib-svr4.c (enable_break): Pass down target.
* spu-multiarch.c (parse_spufs_run): Pass down target.
* spu-tdep.c (spu2ppu_sniffer): Pass down target.
* target-delegates.c: Regenerate.
* target.c (g_target_stack): Delete.
(current_top_target): Return the current inferior's top target.
(target_has_execution_1): Refer to the passed-in inferior's top
target.
(target_supports_terminal_ours): Check whether the initial
inferior was already created.
(decref_target): New.
(target_stack::push): Incref/decref the target.
(push_target, push_target, unpush_target): Adjust.
(target_stack::unpush): Defref target.
(target_is_pushed): Return bool. Adjust to refer to the current
inferior's target stack.
(dispose_inferior): Delete, and inline parts ...
(target_preopen): ... here. Only dispose of the current inferior.
(target_detach): Hold strong target reference while detaching.
Pass target down.
(target_thread_name): Add assertion.
(target_resume): Pass down target.
(target_ops::beneath, find_target_at): Adjust to refer to the
current inferior's target stack.
(get_dummy_target): New.
(target_pass_ctrlc): Pass the Ctrl-C to the first inferior that
has a thread running.
(initialize_targets): Rename to ...
(_initialize_target): ... this.
* target.h: Include "gdbsupport/refcounted-object.h".
(struct target_ops): Inherit refcounted_object.
(target_ops::shortname, target_ops::longname): Make const.
(target_ops::async_wait_fd): New method.
(decref_target): Declare.
(struct target_ops_ref_policy): New.
(target_ops_ref): New typedef.
(get_dummy_target): Declare function.
(target_is_pushed): Return bool.
* thread-iter.c (all_matching_threads_iterator::m_inf_matches)
(all_matching_threads_iterator::all_matching_threads_iterator):
Handle filter target.
* thread-iter.h (struct all_matching_threads_iterator, struct
all_matching_threads_range, class all_non_exited_threads_range):
Filter by target too. Remove explicit.
* thread.c (threads_executing): Delete.
(inferior_thread): Pass down current inferior.
(clear_thread_inferior_resources): Pass down thread pointer
instead of ptid_t.
(add_thread_silent, add_thread_with_info, add_thread): Add
process_stratum_target parameter. Use it for thread and inferior
searches.
(is_current_thread): New.
(thread_info::deletable): Use it.
(find_thread_ptid, thread_count, in_thread_list)
(thread_change_ptid, set_resumed, set_running): New
process_stratum_target parameter. Pass it down.
(set_executing): New process_stratum_target parameter. Pass it
down. Adjust reference to 'threads_executing'.
(threads_are_executing): New process_stratum_target parameter.
Adjust reference to 'threads_executing'.
(set_stop_requested, finish_thread_state): New
process_stratum_target parameter. Pass it down.
(switch_to_thread): Also match inferior.
(switch_to_thread): New process_stratum_target parameter. Pass it
down.
(update_threads_executing): Reimplement.
* top.c (quit_force): Pop targets from all inferior.
(gdb_init): Don't call initialize_targets.
* windows-nat.c (windows_nat_target) <get_windows_debug_event>:
Declare.
(windows_add_thread, windows_delete_thread): Adjust.
(get_windows_debug_event): Rename to ...
(windows_nat_target::get_windows_debug_event): ... this. Adjust.
* tracefile-tfile.c (tfile_target_open): Pass down target.
* gdbsupport/common-gdbthread.h (struct process_stratum_target):
Forward declare.
(switch_to_thread): Add process_stratum_target parameter.
* mi/mi-interp.c (mi_on_resume_1): Add process_stratum_target
parameter. Use it.
(mi_on_resume): Pass target down.
* nat/fork-inferior.c (startup_inferior): Add
process_stratum_target parameter. Pass it down.
* nat/fork-inferior.h (startup_inferior): Add
process_stratum_target parameter.
* python/py-threadevent.c (py_get_event_thread): Pass target down.
gdb/gdbserver/ChangeLog:
2020-01-10 Pedro Alves <palves@redhat.com>
* fork-child.c (post_fork_inferior): Pass target down to
startup_inferior.
* inferiors.c (switch_to_thread): Add process_stratum_target
parameter.
* lynx-low.c (lynx_target_ops): Now a process_stratum_target.
* nto-low.c (nto_target_ops): Now a process_stratum_target.
* linux-low.c (linux_target_ops): Now a process_stratum_target.
* remote-utils.c (prepare_resume_reply): Pass the target to
switch_to_thread.
* target.c (the_target): Now a process_stratum_target.
(done_accessing_memory): Pass the target to switch_to_thread.
(set_target_ops): Ajust to use process_stratum_target.
* target.h (struct target_ops): Rename to ...
(struct process_stratum_target): ... this.
(the_target, set_target_ops): Adjust.
(prepare_to_access_memory): Adjust comment.
* win32-low.c (child_xfer_memory): Adjust to use
process_stratum_target.
(win32_target_ops): Now a process_stratum_target.
- Make get_last_target_status arguments optional. A following patch
will add another argument to get_last_target_status (the event's
target), and passing nullptr when we don't care for some piece of
info is handier than creating dummy local variables.
- Declare nullify_last_target_wait_ptid in a header, and remove the
local extern declaration from linux-fork.c.
gdb/ChangeLog:
2020-01-10 Pedro Alves <palves@redhat.com>
* break-catch-sig.c (signal_catchpoint_print_it): Don't pass a
ptid to get_last_target_status.
* break-catch-syscall.c (print_it_catch_syscall): Don't pass a
ptid to get_last_target_status.
* infcmd.c (continue_command): Don't pass a target_waitstatus to
get_last_target_status.
(info_program_command): Don't pass a target_waitstatus to
get_last_target_status.
* infrun.c (init_wait_for_inferior): Use
nullify_last_target_wait_ptid.
(get_last_target_status): Handle nullptr arguments.
(nullify_last_target_wait_ptid): Clear target_last_waitstatus.
(print_stop_event): Don't pass a ptid to get_last_target_status.
(normal_stop): Don't pass a ptid to get_last_target_status.
* infrun.h (get_last_target_status, set_last_target_status): Move
comments here and update.
(nullify_last_target_wait_ptid): Declare.
* linux-fork.c (fork_load_infrun_state): Remove local extern
declaration of nullify_last_target_wait_ptid.
* linux-nat.c (get_detach_signal): Don't pass a target_waitstatus
to get_last_target_status.
This adds configury support and an RAII class that can be used to
temporarily block signals that are used by gdb. (This class is not
used in this patch, but it split out for easier review.)
The idea of this patch is that these signals should only be delivered
to the main thread. So, when creating a background thread, they are
temporarily blocked; the blocked state is inherited by the new thread.
The sigprocmask man page says:
The use of sigprocmask() is unspecified in a multithreaded
process; see pthread_sigmask(3).
This patch changes gdb to use pthread_sigmask when appropriate, by
introducing a convenience define.
I've updated gdbserver as well, because I had to touch gdbsupport, and
because the threading patches will make it link against the thread
library.
I chose not to touch the NTO code, because I don't know anything about
that platform and because I cannot test it.
Finally, this modifies an existing spot in the Guile layer to use the
new facility.
gdb/ChangeLog
2019-11-26 Tom Tromey <tom@tromey.com>
* gdbsupport/signals-state-save-restore.c (original_signal_mask):
Remove comment.
(save_original_signals_state, restore_original_signals_state): Use
gdb_sigmask.
* linux-nat.c (block_child_signals, restore_child_signals_mask)
(_initialize_linux_nat): Use gdb_sigmask.
* guile/guile.c (_initialize_guile): Use block_signals.
* Makefile.in (HFILES_NO_SRCDIR): Add gdb-sigmask.h.
* gdbsupport/gdb-sigmask.h: New file.
* event-top.c (async_sigtstp_handler): Use gdb_sigmask.
* cp-support.c (gdb_demangle): Use gdb_sigmask.
* gdbsupport/common.m4 (GDB_AC_COMMON): Check for
pthread_sigmask.
* configure, config.in: Rebuild.
* gdbsupport/block-signals.h: New file.
gdb/gdbserver/ChangeLog
2019-11-26 Tom Tromey <tom@tromey.com>
* remote-utils.c (block_unblock_async_io): Use gdb_sigmask.
* linux-low.c (linux_wait_for_event_filtered, linux_async): Use
gdb_sigmask.
* configure, config.in: Rebuild.
Change-Id: If3f37dc57dd859c226e9e4d79458a0514746e8c6
This provides threadsafety. Unfortunately, since libinproctrace.so
does not link to gnulib, we can't use it there, especially since it
still includes the gnulib headers (so it is difficult to directly
call the system strerror_r).
gdb/ChangeLog:
2019-11-26 Christian Biesinger <cbiesinger@google.com>
* linux-nat.c (detach_one_lwp): Call safe_strerror instead of
strerror.
* nto-procfs.c (nto_procfs_target::create_inferior): Likewise.
* windows-nat.c (windows_nat_target::create_inferior): Likewise.
gdb/gdbserver/ChangeLog:
2019-11-26 Christian Biesinger <cbiesinger@google.com>
* debug.c (debug_set_output): Call safe_strerror instead of
strerror.
* linux-low.c (attach_proc_task_lwp_callback): Likewise.
(linux_kill_one_lwp): Likewise.
(linux_detach_one_lwp): Likewise.
(linux_wait_for_event_filtered): Likewise.
(store_register): Likewise.
* lynx-low.c (lynx_attach): Likewise.
* mem-break.c (insert_memory_breakpoint): Likewise.
(remove_memory_breakpoint): Likewise.
(delete_fast_tracepoint_jump): Likewise.
(set_fast_tracepoint_jump): Likewise.
(uninsert_fast_tracepoint_jumps_at): Likewise.
(reinsert_fast_tracepoint_jumps_at): Likewise.
* nto-low.c (nto_xfer_memory): Likewise.
(nto_resume): Likewise.
Change-Id: I9e259cdcaa6e11bbcc4ee6bdc5b7127d73e11abe
It was observed that in a multi-threaded application on GNU/Linux,
that if the user has set the SIGSTOP to be pass (using GDB's handle
command) then the inferior would hang upon hitting a breakpoint.
What happens is that when a thread hits the breakpoint GDB tries to
stop all of the other threads by sending them a SIGSTOP and setting
the stop_requested flag in the target_ops structure - this can be seen
in infrun.c:stop_all_threads.
GDB then waits for all of the other threads to stop.
When the SIGSTOP event arrives we eventually end up in
linux-nat.c:linux_nat_filter_event, which has the job of deciding if
the event we're looking at (the SIGSTOP arriving in this case) is
something that should be reported back to the core of GDB.
One of the final actions of this function is to check if we stopped
due to a signal, and if we did, and the signal has been set to 'pass'
by the user then we ignore the event and resume the thread.
This code already has some conditions in place that mean the event is
reported to GDB even if the signal is in the set of signals to be
passed to the inferior.
In this commit I extend this condition such that:
If the signal is a SIGSTOP, and the thread's stop_requested flag is
set (indicating we're waiting for the thread to stop with a SIGSTOP)
then we should report this SIGSTOP to GDB and not pass it to the
inferior.
With this change in place the test now passes. Regression tested on
x86-64 GNU/Linux with no regressions.
gdb/ChangeLog:
* linux-nat.c (linux_nat_filter_event): Don't ignore SIGSTOP if we
have just sent the thread a SIGSTOP and are waiting for it to
arrive.
gdb/testsuite/ChangeLog:
* gdb.threads/stop-with-handle.c: New file.
* gdb.threads/stop-with-handle.exp: New file.
In Fedora GDB, we carry the following patch:
8ac06474ff/f/gdb-attach-fail-reasons-5of5.patch
Its purpose is to try to detect a specific scenario where SELinux's
'deny_ptrace' option is enabled, which prevents GDB from ptrace'ing in
order to debug the inferior (PTRACE_ATTACH and PTRACE_TRACEME will
fail with EACCES in this case).
I like the idea of improving error detection and providing more
information to the user (a simple "Permission denied" can be really
frustrating), but I don't fully agree with the way the patch was
implemented: it makes GDB link against libselinux only for the sake of
consulting the 'deny_ptrace' setting, and then prints a warning if
ptrace failed and this setting is on.
My first thought (and attempt) was to make GDB print a generic warning
when a ptrace error happened; this message would just point the user
to our documentation, where she could find more information about
possible causes for the error (and try to diagnose/fix the problem).
This proved to be too simple, and I was convinced that it is actually
a good idea to go the extra kilometre and try to pinpoint the specific
problem (or problems) preventing ptrace from working, as well as
provide useful suggestions on how the user can fix things.
Here is the patch I came up with. It implements a new function,
'linux_ptrace_restricted_fail_reason', which does a few things to
check what's wrong with ptrace:
- It dlopen's "libselinux.so.1" and checks if the "deny_ptrace"
option is enabled.
- It reads the contents of "/proc/sys/kernel/yama/ptrace_scope" and
checks if it's different than 0.
For each of these checks, if it succeeds, the user will see a message
informing about the restriction in place, and how it can be disabled.
For example, if "deny_ptrace" is enabled, the user will see:
# gdb /usr/bin/true
...
Starting program: /usr/bin/true
warning: Could not trace the inferior process.
warning: ptrace: Permission denied
The SELinux 'deny_ptrace' option is enabled and preventing GDB
from using 'ptrace'. You can disable it by executing (as root):
setsebool deny_ptrace off
If you are debugging the inferior remotely, the ptrace restriction(s) need
to be disabled in the target system (e.g., where GDBserver is running).
During startup program exited with code 127.
(gdb)
In case "/proc/sys/kernel/yama/ptrace_scope" is > 0:
# gdb /usr/bin/true
...
Starting program: /usr/bin/true
warning: Could not trace the inferior process.
warning: ptrace: Operation not permitted
The Linux kernel's Yama ptrace scope is in effect, which can prevent
GDB from using 'ptrace'. You can disable it by executing (as root):
echo 0 > /proc/sys/kernel/yama/ptrace_scope
If you are debugging the inferior remotely, the ptrace restriction(s) need
to be disabled in the target system (e.g., where GDBserver is running).
During startup program exited with code 127.
(gdb)
If both restrictions are enabled, both messages will show up.
This works for gdbserver as well, and actually fixes a latent bug I
found: when ptrace is restricted, gdbserver would hang due to an
unchecked ptrace call:
# gdbserver :9988 /usr/bin/true
gdbserver: linux_ptrace_test_ret_to_nx: Cannot PTRACE_TRACEME: Operation not permitted
gdbserver: linux_ptrace_test_ret_to_nx: status 256 is not WIFSTOPPED!
gdbserver: linux_ptrace_test_ret_to_nx: failed to kill child pid 2668100 No such process
[ Here you would have to issue a C-c ]
Now, you will see:
# gdbserver :9988 /usr/bin/true
gdbserver: linux_ptrace_test_ret_to_nx: Cannot PTRACE_TRACEME: Permission denied
gdbserver: linux_ptrace_test_ret_to_nx: status 256 is not WIFSTOPPED!
gdbserver: linux_ptrace_test_ret_to_nx: failed to kill child pid 2766868 No such process
gdbserver: Could not trace the inferior process.
gdbserver: ptrace: Permission denied
The SELinux 'deny_ptrace' option is enabled and preventing GDB
from using 'ptrace'. You can disable it by executing (as root):
setsebool deny_ptrace off
If you are debugging the inferior remotely, the ptrace restriction(s) need
to be disabled in the target system (e.g., where GDBserver is running).
#
(I decided to keep all the other messages, even though I find them a
bit distracting).
If GDB can't determine the cause for the failure, it will still print
the generic error message which tells the user to check our
documentation:
There might be restrictions preventing ptrace from working. Please see
the appendix "Linux kernel ptrace restrictions" in the GDB documentation
for more details.
If you are debugging the inferior remotely, the ptrace restriction(s) need
to be disabled in the target system (e.g., where GDBserver is running).
This means that the patch expands our documentation and creates a new
appendix section named "Linux kernel ptrace restrictions", with
sub-sections for each possible restriction that might be in place.
Notice how, on every message, we instruct the user to "do the right
thing" if gdbserver is being used. This is because if the user
started gdbserver *before* any ptrace restriction was in place, and
then, for some reason, one or more restrictions get enabled, then the
error message will be displayed both on gdbserver *and* on the
connected GDB. Since the user will be piloting GDB, it's important to
explicitly say that the ptrace restrictions are enabled in the target,
where gdbserver is running.
The current list of possible restrictions is:
- SELinux's 'deny_ptrace' option (detected).
- YAMA's /proc/sys/kernel/yama/ptrace_scope setting (detected).
- seccomp on Docker containers (I couldn't find how to detect).
It's important to mention that all of this is Linux-specific; as far
as I know, SELinux, YAMA and seccomp are Linux-only features.
I tested this patch locally, on my Fedora 30 machine (actually, a
Fedora Rawhide VM), but I'm not proposing a testcase for it because of
the difficulty of writing one.
WDYT?
gdb/doc/ChangeLog:
2019-09-26 Sergio Durigan Junior <sergiodj@redhat.com>
* gdb.texinfo (Linux kernel ptrace restrictions): New appendix
section.
gdb/ChangeLog:
2019-09-26 Sergio Durigan Junior <sergiodj@redhat.com>
Jan Kratochvil <jan.kratochvil@redhat.com>
Pedro Alves <palves@redhat.com>
* gdbsupport/gdb-dlfcn.h (gdb_dlopen): Update comment and
mention that the function throws an error.
* inf-ptrace.c (default_inf_ptrace_me_fail_reason): New
function.
(inf_ptrace_me_fail_reason): New variable.
(inf_ptrace_me): Update call to 'trace_start_error_with_name'.
* inf-ptrace.h (inf_ptrace_me_fail_reason): New variable.
* linux-nat.c (attach_proc_task_lwp_callback): Call
'linux_ptrace_attach_fail_reason_lwp'.
(linux_nat_target::attach): Update call to
'linux_ptrace_attach_fail_reason'.
(_initialize_linux_nat): Set 'inf_ptrace_me_fail_reason'.
* nat/fork-inferior.c (trace_start_error_with_name): Add
optional 'append' argument.
* nat/fork-inferior.h (trace_start_error_with_name): Update
prototype.
* nat/linux-ptrace.c: Include "gdbsupport/gdb-dlfcn.h",
"gdbsupport/filestuff.h" and "nat/fork-inferior.h".
(selinux_ftype): New typedef.
(linux_ptrace_restricted_fail_reason): New function.
(linux_ptrace_attach_fail_reason_1): New function.
(linux_ptrace_attach_fail_reason): Change first argument type
from 'ptid_t' to 'pid_t'. Call
'linux_ptrace_attach_fail_reason_1' and
'linux_ptrace_restricted_fail_reason'.
(linux_ptrace_attach_fail_reason_lwp): New function.
(linux_ptrace_me_fail_reason): New function.
(errno_pipe): New variable.
(linux_fork_to_function): Initialize pipe before forking.
(linux_child_function): Deal with errno-passing from child.
Handle ptrace error.
(linux_check_child_ptrace_errno): New function.
(linux_check_child_ptrace_errno): Call
'linux_check_child_ptrace_errno'.
* nat/linux-ptrace.h (linux_ptrace_attach_fail_reason): Update
prototype.
(linux_ptrace_attach_fail_reason_lwp): New prototype.
(linux_ptrace_me_fail_reason): New prototype.
* remote.c (extended_remote_target::attach): Handle error
message passed by the server when attach fails.
gdb/gdbserver/ChangeLog:
2019-09-26 Sergio Durigan Junior <sergiodj@redhat.com>
Pedro Alves <palves@redhat.com>
* linux-low.c (linux_ptrace_fun): Call
'linux_ptrace_me_fail_reason'.
(attach_proc_task_lwp_callback): Call
'linux_ptrace_attach_fail_reason_lwp'.
(linux_attach): Call 'linux_ptrace_attach_fail_reason'.
* server.c (handle_v_attach): Use try..catch when calling
'attach_inferior', and send an error message to the client
when needed.
* thread-db.c (attach_thread): Call
'linux_ptrace_attach_fail_reason_lwp'.
In the following commit:
commit 7feb7d068a
Date: Mon May 11 12:08:03 2009 +0000
The last useful uses of normal_mask in linux-nat.c were removed, since
then this variable has sat around being initialised, but never used.
There should be no user visible changes after this commit.
gdb/ChangeLog:
* linux-nat.c (normal_mask): Delete.
(_initialize_linux_nat): Don't initialise normal_mask.
This rewrites gdb's TRY/CATCH to plain C++ try/catch. The patch was
largely written by script, though one change (to a comment in
common-exceptions.h) was reverted by hand.
gdb/ChangeLog
2019-04-08 Tom Tromey <tom@tromey.com>
* xml-support.c: Use C++ exception handling.
* x86-linux-nat.c: Use C++ exception handling.
* windows-nat.c: Use C++ exception handling.
* varobj.c: Use C++ exception handling.
* value.c: Use C++ exception handling.
* valprint.c: Use C++ exception handling.
* valops.c: Use C++ exception handling.
* unittests/parse-connection-spec-selftests.c: Use C++ exception
handling.
* unittests/cli-utils-selftests.c: Use C++ exception handling.
* typeprint.c: Use C++ exception handling.
* tui/tui.c: Use C++ exception handling.
* tracefile-tfile.c: Use C++ exception handling.
* top.c: Use C++ exception handling.
* thread.c: Use C++ exception handling.
* target.c: Use C++ exception handling.
* symmisc.c: Use C++ exception handling.
* symfile-mem.c: Use C++ exception handling.
* stack.c: Use C++ exception handling.
* sparc64-linux-tdep.c: Use C++ exception handling.
* solib.c: Use C++ exception handling.
* solib-svr4.c: Use C++ exception handling.
* solib-spu.c: Use C++ exception handling.
* solib-frv.c: Use C++ exception handling.
* solib-dsbt.c: Use C++ exception handling.
* selftest-arch.c: Use C++ exception handling.
* s390-tdep.c: Use C++ exception handling.
* rust-lang.c: Use C++ exception handling.
* rust-exp.y: Use C++ exception handling.
* rs6000-tdep.c: Use C++ exception handling.
* rs6000-aix-tdep.c: Use C++ exception handling.
* riscv-tdep.c: Use C++ exception handling.
* remote.c: Use C++ exception handling.
* remote-fileio.c: Use C++ exception handling.
* record-full.c: Use C++ exception handling.
* record-btrace.c: Use C++ exception handling.
* python/python.c: Use C++ exception handling.
* python/py-value.c: Use C++ exception handling.
* python/py-utils.c: Use C++ exception handling.
* python/py-unwind.c: Use C++ exception handling.
* python/py-type.c: Use C++ exception handling.
* python/py-symbol.c: Use C++ exception handling.
* python/py-record.c: Use C++ exception handling.
* python/py-record-btrace.c: Use C++ exception handling.
* python/py-progspace.c: Use C++ exception handling.
* python/py-prettyprint.c: Use C++ exception handling.
* python/py-param.c: Use C++ exception handling.
* python/py-objfile.c: Use C++ exception handling.
* python/py-linetable.c: Use C++ exception handling.
* python/py-lazy-string.c: Use C++ exception handling.
* python/py-infthread.c: Use C++ exception handling.
* python/py-inferior.c: Use C++ exception handling.
* python/py-gdb-readline.c: Use C++ exception handling.
* python/py-framefilter.c: Use C++ exception handling.
* python/py-frame.c: Use C++ exception handling.
* python/py-finishbreakpoint.c: Use C++ exception handling.
* python/py-cmd.c: Use C++ exception handling.
* python/py-breakpoint.c: Use C++ exception handling.
* python/py-arch.c: Use C++ exception handling.
* printcmd.c: Use C++ exception handling.
* ppc-linux-tdep.c: Use C++ exception handling.
* parse.c: Use C++ exception handling.
* p-valprint.c: Use C++ exception handling.
* objc-lang.c: Use C++ exception handling.
* mi/mi-main.c: Use C++ exception handling.
* mi/mi-interp.c: Use C++ exception handling.
* mi/mi-cmd-stack.c: Use C++ exception handling.
* mi/mi-cmd-break.c: Use C++ exception handling.
* main.c: Use C++ exception handling.
* linux-thread-db.c: Use C++ exception handling.
* linux-tdep.c: Use C++ exception handling.
* linux-nat.c: Use C++ exception handling.
* linux-fork.c: Use C++ exception handling.
* linespec.c: Use C++ exception handling.
* language.c: Use C++ exception handling.
* jit.c: Use C++ exception handling.
* infrun.c: Use C++ exception handling.
* infcmd.c: Use C++ exception handling.
* infcall.c: Use C++ exception handling.
* inf-loop.c: Use C++ exception handling.
* i386-tdep.c: Use C++ exception handling.
* i386-linux-tdep.c: Use C++ exception handling.
* guile/scm-value.c: Use C++ exception handling.
* guile/scm-type.c: Use C++ exception handling.
* guile/scm-symtab.c: Use C++ exception handling.
* guile/scm-symbol.c: Use C++ exception handling.
* guile/scm-pretty-print.c: Use C++ exception handling.
* guile/scm-ports.c: Use C++ exception handling.
* guile/scm-param.c: Use C++ exception handling.
* guile/scm-math.c: Use C++ exception handling.
* guile/scm-lazy-string.c: Use C++ exception handling.
* guile/scm-frame.c: Use C++ exception handling.
* guile/scm-disasm.c: Use C++ exception handling.
* guile/scm-cmd.c: Use C++ exception handling.
* guile/scm-breakpoint.c: Use C++ exception handling.
* guile/scm-block.c: Use C++ exception handling.
* guile/guile-internal.h: Use C++ exception handling.
* gnu-v3-abi.c: Use C++ exception handling.
* gdbtypes.c: Use C++ exception handling.
* frame.c: Use C++ exception handling.
* frame-unwind.c: Use C++ exception handling.
* fbsd-tdep.c: Use C++ exception handling.
* f-valprint.c: Use C++ exception handling.
* exec.c: Use C++ exception handling.
* event-top.c: Use C++ exception handling.
* event-loop.c: Use C++ exception handling.
* eval.c: Use C++ exception handling.
* dwarf2read.c: Use C++ exception handling.
* dwarf2loc.c: Use C++ exception handling.
* dwarf2-frame.c: Use C++ exception handling.
* dwarf2-frame-tailcall.c: Use C++ exception handling.
* dwarf-index-write.c: Use C++ exception handling.
* dwarf-index-cache.c: Use C++ exception handling.
* dtrace-probe.c: Use C++ exception handling.
* disasm-selftests.c: Use C++ exception handling.
* darwin-nat.c: Use C++ exception handling.
* cp-valprint.c: Use C++ exception handling.
* cp-support.c: Use C++ exception handling.
* cp-abi.c: Use C++ exception handling.
* corelow.c: Use C++ exception handling.
* completer.c: Use C++ exception handling.
* compile/compile-object-run.c: Use C++ exception handling.
* compile/compile-object-load.c: Use C++ exception handling.
* compile/compile-cplus-symbols.c: Use C++ exception handling.
* compile/compile-c-symbols.c: Use C++ exception handling.
* common/selftest.c: Use C++ exception handling.
* common/new-op.c: Use C++ exception handling.
* cli/cli-script.c: Use C++ exception handling.
* cli/cli-interp.c: Use C++ exception handling.
* cli/cli-cmds.c: Use C++ exception handling.
* c-varobj.c: Use C++ exception handling.
* btrace.c: Use C++ exception handling.
* breakpoint.c: Use C++ exception handling.
* break-catch-throw.c: Use C++ exception handling.
* arch-utils.c: Use C++ exception handling.
* amd64-tdep.c: Use C++ exception handling.
* ada-valprint.c: Use C++ exception handling.
* ada-typeprint.c: Use C++ exception handling.
* ada-lang.c: Use C++ exception handling.
* aarch64-tdep.c: Use C++ exception handling.
gdb/gdbserver/ChangeLog
2019-04-08 Tom Tromey <tom@tromey.com>
* server.c: Use C++ exception handling.
* linux-low.c: Use C++ exception handling.
* gdbreplay.c: Use C++ exception handling.
This replaces the pointer and length parameters of target_pass_signals
and target_program_signals with a gdb::array_view parameter, and fixes
the fallout.
In infrun.c, the signal_stop, signal_print, signal_program,
signal_catch, signal_pass globals are currently pointers to
heap-allocated memory. I see no point in that, so I converted them to
arrays. This allows simplifying the calls to
target_pass_signals/target_program_signals, since we can pass the
array directly, which can implicitly convert to gdb::array_view.
gdb/ChangeLog:
2019-01-24 Pedro Alves <palves@redhat.com>
* infrun.c (signal_stop, signal_print, signal_program)
(signal_catch, signal_pass): Now arrays instead of pointers.
(update_signals_program_target, do_target_resume)
(signal_catch_update, handle_command, _initialize_infrun): Adjust.
* linux-nat.c (linux_nat_target::pass_signals)
(linux_nat_target::create_inferior, linux_nat_target::attach):
Adjust.
* linux-nat.h (linux_nat_target::pass_signals): Adjust.
* nto-procfs.c (nto_procfs_target::pass_signals): Adjust.
* procfs.c (procfs_target::pass_signals): Adjust.
* record-full.c (record_full_target::resume): Adjust.
* remote.c (remote_target::pass_signals)
(remote_target::program_signals): Adjust.
* target-debug.h (target_debug_print_signals): Now takes a
gdb::array_view as parameter. Adjust.
* target.h (target_ops) <pass_signals, program_signals>: Replace
pointer and length parameters with gdb::array_view.
(target_pass_signals, target_program_signals): Likewise.
* target-delegates.c: Regenerate.
This removes a cleanup from linux-nat.c, replacing it with a
scope_exit.
gdb/ChangeLog:
2019-01-23 Tom Tromey <tom@tromey.com>
Pedro Alves <palves@redhat.com>
* linux-nat.c: Include scope-exit.h.
(cleanup_target_stop): Remove.
(linux_nat_target::static_tracepoint_markers_by_strid): Use
SCOPE_EXIT.
This constifies the final parameter to target_pass_signals and
target_program_signals and updates the rest of gdb.
Note that I have no way to test the nto-procfs.c change.
gdb/ChangeLog
2019-01-14 Tom Tromey <tom@tromey.com>
* target-debug.h (target_debug_print_signals): Constify.
* nto-procfs.c (nto_procfs_target::pass_signals): Update.
* procfs.c (procfs_target::pass_signals): Update.
* linux-nat.c (linux_nat_target::pass_signals): Update.
* linux-nat.h (class linux_nat_target) <pass_signals>: Update.
* target-delegates.c: Rebuild.
* remote.c (remote_target::program_signals): Update.
(remote_target::pass_signals): Update.
* target.c (target_pass_signals): Constify argument.
(target_program_signals): Likewise.
* target.h (struct target_ops) <pass_signals, program_signals>:
Constify argument.
(target_pass_signals, target_program_signals): Constify argument.
Remove cleanup from linux_nat_target::follow_fork, instead add a new
unique_ptr specialisation for holding lwp_info pointers and use this
to ensure the pointer is cleaned up when needed.
gdb/ChangeLog:
* linux-nat.c (delete_lwp_cleanup): Delete.
(struct lwp_deleter): New struct.
(lwp_info_up): New typedef.
(linux_nat_target::follow_fork): Delete cleanup, and make use of
lwp_info_up.
This commit applies all changes made after running the gdb/copyright.py
script.
Note that one file was flagged by the script, due to an invalid
copyright header
(gdb/unittests/basic_string_view/element_access/char/empty.cc).
As the file was copied from GCC's libstdc++-v3 testsuite, this commit
leaves this file untouched for the time being; a patch to fix the header
was sent to gcc-patches first.
gdb/ChangeLog:
Update copyright year range in all GDB files.
As preparation for multi-target, this patch makes each inferior have
its own thread list.
This isn't absolutely necessary for multi-target, but simplifies
things. It originally stemmed from the desire to eliminate the
init_thread_list calls sprinkled around, plus it makes it more
efficient to iterate over threads of a given inferior (no need to
always iterate over threads of all inferiors).
We still need to iterate over threads of all inferiors in a number of
places, which means we'd need adjust the ALL_THREADS /
ALL_NON_EXITED_THREADS macros. However, naively tweaking those macros
to have an extra for loop, like:
#define ALL_THREADS (thr, inf) \
for (inf = inferior_list; inf; inf = inf->next) \
for (thr = inf->thread_list; thr; thr = thr->next)
causes problems with code that does "break" or "continue" within the
ALL_THREADS loop body. Plus, we need to declare the extra "inf" local
variable in order to pass it as temporary variable to ALL_THREADS
(etc.)
It gets even trickier when we consider extending the macros to filter
out threads matching a ptid_t and a target. The macros become tricker
to read/write. Been there.
An alternative (which was my next attempt), is to replace the
ALL_THREADS etc. iteration style with for_each_all_threads,
for_each_non_exited_threads, etc. functions which would take a
callback as parameter, which would usually be passed a lambda.
However, I did not find that satisfactory at all, because the
resulting code ends up a little less natural / more noisy to read,
write and debug/step-through (due to use of lambdas), and in many
places where we use "continue;" to skip to the next thread now need to
use "return;". (I ran into hard to debug bugs caused by a
continue/return confusion.)
I.e., before:
ALL_NON_EXITED_THREADS (tp)
{
if (tp->not_what_I_want)
continue;
// do something
}
would turn into:
for_each_non_exited_thread ([&] (thread_info *tp)
{
if (tp->not_what_I_want)
return;
// do something
});
Lastly, the solution I settled with was to replace the ALL_THREADS /
ALL_NON_EXITED_THREADS / ALL_INFERIORS macros with (C++20-like) ranges
and iterators, such that you can instead naturaly iterate over
threads/inferiors using range-for, like e.g,.:
// all threads, including THREAD_EXITED threads.
for (thread_info *tp : all_threads ())
{ .... }
// all non-exited threads.
for (thread_info *tp : all_non_exited_threads ())
{ .... }
// all non-exited threads of INF inferior.
for (thread_info *tp : inf->non_exited_threads ())
{ .... }
The all_non_exited_threads() function takes an optional filter ptid_t as
parameter, which is quite convenient when we need to iterate over
threads matching that filter. See e.g., how the
set_executing/set_stop_requested/finish_thread_state etc. functions in
thread.c end up being simplified.
Most of the patch thus is about adding the infrustructure for allowing
the above. Later on when we get to actual multi-target, these
functions/ranges/iterators will gain a "target_ops *" parameter so
that e.g., we can iterate over all threads of a given target that
match a given filter ptid_t.
The only entry points users needs to be aware of are the
all_threads/all_non_exited_threads etc. functions seen above. Thus,
those functions are declared in gdbthread.h/inferior.h. The actual
iterators/ranges are mainly "internals" and thus are put out of view
in the new thread-iter.h/thread-iter.c/inferior-iter.h files. That
keeps the gdbthread.h/inferior.h headers quite a bit more readable.
A common/safe-iterator.h header is added which adds a template that
can be used to build "safe" iterators, which are forward iterators
that can be used to replace the ALL_THREADS_SAFE macro and other
instances of the same idiom in future.
There's a little bit of shuffling of code between
gdbthread.h/thread.c/inferior.h in the patch. That is necessary in
order to avoid circular dependencies between the
gdbthread.h/inferior.h headers.
As for the init_thread_list calls sprinkled around, they're all
eliminated by this patch, and a new, central call is added to
inferior_appeared. Note how also related to that, there's a call to
init_wait_for_inferior in remote.c that is eliminated.
init_wait_for_inferior is currently responsible for discarding skipped
inline frames, which had to be moved elsewhere. Given that nowadays
we always have a thread even for single-threaded processes, the
natural place is to delete a frame's inline frame info when we delete
the thread. I.e., from clear_thread_inferior_resources.
gdb/ChangeLog:
2018-11-22 Pedro Alves <palves@redhat.com>
* Makefile.in (COMMON_SFILES): Add thread-iter.c.
* breakpoint.c (breakpoints_should_be_inserted_now): Replace
ALL_NON_EXITED_THREADS with all_non_exited_threads.
(print_one_breakpoint_location): Replace ALL_INFERIORS with
all_inferiors.
* bsd-kvm.c: Include inferior.h.
* btrace.c (btrace_free_objfile): Replace ALL_NON_EXITED_THREADS
with all_non_exited_threads.
* common/filtered-iterator.h: New.
* common/safe-iterator.h: New.
* corelow.c (core_target_open): Don't call init_thread_list here.
* darwin-nat.c (thread_info_from_private_thread_info): Replace
ALL_THREADS with all_threads.
* fbsd-nat.c (fbsd_nat_target::resume): Replace
ALL_NON_EXITED_THREADS with inf->non_exited_threads.
* fbsd-tdep.c (fbsd_make_corefile_notes): Replace
ALL_NON_EXITED_THREADS with inf->non_exited_threads.
* fork-child.c (postfork_hook): Don't call init_thread_list here.
* gdbarch-selftests.c (register_to_value_test): Adjust.
* gdbthread.h: Don't include "inferior.h" here.
(struct inferior): Forward declare.
(enum step_over_calls_kind): Moved here from inferior.h.
(thread_info::deletable): Definition moved to thread.c.
(find_thread_ptid (inferior *, ptid_t)): Declare.
(ALL_THREADS, ALL_THREADS_BY_INFERIOR, ALL_THREADS_SAFE): Delete.
Include "thread-iter.h".
(all_threads, all_non_exited_threads, all_threads_safe): New.
(any_thread_p): Declare.
(thread_list): Delete.
* infcmd.c (signal_command): Replace ALL_NON_EXITED_THREADS with
all_non_exited_threads.
(proceed_after_attach_callback): Delete.
(proceed_after_attach): Take an inferior pointer instead of an
integer PID. Adjust to use range-for.
(attach_post_wait): Pass down inferior pointer instead of pid.
Use range-for instead of ALL_NON_EXITED_THREADS.
(detach_command): Remove init_thread_list call.
* inferior-iter.h: New.
* inferior.c (struct delete_thread_of_inferior_arg): Delete.
(delete_thread_of_inferior): Delete.
(delete_inferior, exit_inferior_1): Use range-for with
inf->threads_safe() instead of iterate_over_threads.
(inferior_appeared): Call init_thread_list here.
(discard_all_inferiors): Use all_non_exited_inferiors.
(find_inferior_id, find_inferior_pid): Use all_inferiors.
(iterate_over_inferiors): Use all_inferiors_safe.
(have_inferiors, number_of_live_inferiors): Use
all_non_exited_inferiors.
(number_of_inferiors): Use all_inferiors and std::distance.
(print_inferior): Use all_inferiors.
* inferior.h: Include gdbthread.h.
(enum step_over_calls_kind): Moved to gdbthread.h.
(struct inferior) <thread_list>: New field.
<threads, non_exited_threads, threads_safe>: New methods.
(ALL_INFERIORS): Delete.
Include "inferior-iter.h".
(ALL_NON_EXITED_INFERIORS): Delete.
(all_inferiors_safe, all_inferiors, all_non_exited_inferiors): New
functions.
* inflow.c (child_interrupt, child_pass_ctrlc): Replace
ALL_NON_EXITED_THREADS with all_non_exited_threads.
* infrun.c (follow_exec): Use all_threads_safe.
(clear_proceed_status, proceed): Use all_non_exited_threads.
(init_wait_for_inferior): Don't clear inline frame state here.
(infrun_thread_stop_requested, for_each_just_stopped_thread): Use
all_threads instead of ALL_NON_EXITED_THREADS.
(random_pending_event_thread): Use all_non_exited_threads instead
of ALL_NON_EXITED_THREADS. Use a lambda for repeated code.
(clean_up_just_stopped_threads_fsms): Use all_non_exited_threads
instead of ALL_NON_EXITED_THREADS.
(handle_no_resumed): Use all_non_exited_threads instead of
ALL_NON_EXITED_THREADS. Use all_inferiors instead of
ALL_INFERIORS.
(restart_threads, switch_back_to_stepped_thread): Use
all_non_exited_threads instead of ALL_NON_EXITED_THREADS.
* linux-nat.c (check_zombie_leaders): Replace ALL_INFERIORS with
all_inferiors.
(kill_unfollowed_fork_children): Use inf->non_exited_threads
instead of ALL_NON_EXITED_THREADS.
* linux-tdep.c (linux_make_corefile_notes): Use
inf->non_exited_threads instead of ALL_NON_EXITED_THREADS.
* linux-thread-db.c (thread_db_target::update_thread_list):
Replace ALL_INFERIORS with all_inferiors.
(thread_db_target::thread_handle_to_thread_info): Use
inf->non_exited_threads instead of ALL_NON_EXITED_THREADS.
* mi/mi-interp.c (multiple_inferiors_p): New.
(mi_on_resume_1): Simplify using all_non_exited_threads and
multiple_inferiors_p.
* mi/mi-main.c (mi_cmd_thread_list_ids): Use all_non_exited_threads
instead of ALL_NON_EXITED_THREADS.
* nto-procfs.c (nto_procfs_target::open): Don't call
init_thread_list here.
* record-btrace.c (record_btrace_target_open)
(record_btrace_target::stop_recording)
(record_btrace_target::close)
(record_btrace_target::record_is_replaying)
(record_btrace_target::resume, record_btrace_target::wait)
(record_btrace_target::record_stop_replaying): Use
all_non_exited_threads instead of ALL_NON_EXITED_THREADS.
* record-full.c (record_full_wait_1): Use all_non_exited_threads
instead of ALL_NON_EXITED_THREADS.
* regcache.c (cooked_read_test): Remove reference to global
thread_list.
* remote-sim.c (gdbsim_target::create_inferior): Don't call
init_thread_list here.
* remote.c (remote_target::update_thread_list): Use
all_threads_safe instead of ALL_NON_EXITED_THREADS.
(remote_target::process_initial_stop_replies): Replace
ALL_INFERIORS with all_non_exited_inferiors and use
all_non_exited_threads instead of ALL_NON_EXITED_THREADS.
(remote_target::open_1): Don't call init_thread_list here.
(remote_target::append_pending_thread_resumptions)
(remote_target::remote_resume_with_hc): Use all_non_exited_threads
instead of ALL_NON_EXITED_THREADS.
(remote_target::commit_resume)
(remote_target::remove_new_fork_children): Replace ALL_INFERIORS
with all_non_exited_inferiors and use all_non_exited_threads
instead of ALL_NON_EXITED_THREADS.
(remote_target::kill_new_fork_children): Use
all_non_exited_threads instead of ALL_NON_EXITED_THREADS. Remove
init_thread_list and init_wait_for_inferior calls.
(remote_target::remote_btrace_maybe_reopen)
(remote_target::thread_handle_to_thread_info): Use
all_non_exited_threads instead of ALL_NON_EXITED_THREADS.
* target.c (target_terminal::restore_inferior)
(target_terminal_is_ours_kind): Replace ALL_INFERIORS with
all_non_exited_inferiors.
* thread-iter.c: New file.
* thread-iter.h: New file.
* thread.c: Include "inline-frame.h".
(thread_list): Delete.
(clear_thread_inferior_resources): Call clear_inline_frame_state.
(init_thread_list): Use all_threads_safe instead of
ALL_THREADS_SAFE. Adjust to per-inferior thread lists.
(new_thread): Adjust to per-inferior thread lists.
(add_thread_silent): Pass inferior to find_thread_ptid.
(thread_info::deletable): New, moved from the header.
(delete_thread_1): Adjust to per-inferior thread lists.
(find_thread_global_id): Use inf->threads().
(find_thread_ptid): Use find_inferior_ptid and pass inferior to
find_thread_ptid.
(find_thread_ptid(inferior*, ptid_t)): New overload.
(iterate_over_threads): Use all_threads_safe.
(any_thread_p): New.
(thread_count): Use all_threads and std::distance.
(live_threads_count): Use all_non_exited_threads and
std::distance.
(valid_global_thread_id): Use all_threads.
(in_thread_list): Use find_thread_ptid.
(first_thread_of_inferior): Adjust to per-inferior thread lists.
(any_thread_of_inferior, any_live_thread_of_inferior): Use
inf->non_exited_threads().
(prune_threads, delete_exited_threads): Use all_threads_safe.
(thread_change_ptid): Pass inferior pointer to find_thread_ptid.
(set_resumed, set_running): Use all_non_exited_threads.
(is_thread_state, is_stopped, is_exited, is_running)
(is_executing): Delete.
(set_executing, set_stop_requested, finish_thread_state): Use
all_non_exited_threads.
(print_thread_info_1): Use all_inferiors and all_threads.
(thread_apply_all_command): Use all_non_exited_threads.
(thread_find_command): Use all_threads.
(update_threads_executing): Use all_non_exited_threads.
* tid-parse.c (parse_thread_id): Use inf->threads.
* x86-bsd-nat.c (x86bsd_dr_set): Use inf->non_exited_threads ().
Return an std::string instead of a char *, saving some manual freeing.
I only manually tested with "set debug target 1" and "set debug lin-lwp
1", since this only deals with debug output.
gdb/ChangeLog:
* target.h (target_options_to_string): Return an std::string.
* target.c (str_comma_list_concat_elem): Return void, use
std::string.
(do_option): Likewise.
(target_options_to_string): Return an std::string.
* linux-nat.c (linux_nat_target::wait): Adjust.
* target-debug.h (target_debug_print_options): Adjust.
The MIPS target supports 127 signals, and this can create an ambiguity
in process wait statuses. A status value of 0x007f could potentially
indicate a process that has exited with signal 127, or a process that
has stopped with signal 0.
In uClibc-ng the interpretation of 0x007f is that the process has
exited with signal 127 rather than stopped with signal 0, and so,
WIFSTOPPED (W_STOPCODE (0)) will be false rather than true as it would
be on most other platforms.
Given that it's pretty easy to avoid using W_STOPCODE (0), lets do that.
gdb/ChangeLog:
* linux-nat.c (linux_nat_target::follow_fork): Avoid using
'W_STOPCODE (0)' as this could be ambiguous.
Simon Marchi