When debugging two inferiors (or more) against gdbserver, and the
inferiors have different architectures, such as e.g., on x86_64
GNU/Linux and one inferior is 64-bit while the other is 32-bit, then
GDB can get confused with the different architectures in a couple
spots.
In both cases I ran into, GDB incorrectly ended up using the
architecture of whatever happens to be the selected inferior instead
of the architecture of some other given inferior:
#1 - When parsing the expedited registers in stop replies.
#2 - In the default implementation of the target_thread_architecture
target method.
These resulted in instances of the infamous "Remote 'g' packet reply
is too long" error. For example, with the test added in this commit,
we get:
~~~
Continuing.
Remote 'g' packet reply is too long (expected 440 bytes, got 816 bytes): ad064000000000000[snip]
(gdb) FAIL: gdb.multi/multi-arch.exp: inf1 event with inf2 selected: continue to hello_loop
c
Continuing.
Truncated register 50 in remote 'g' packet
(gdb) PASS: gdb.multi/multi-arch.exp: inf2 event with inf1 selected: c
~~~
This commit fixes that.
gdb/ChangeLog:
2017-10-04 Pedro Alves <palves@redhat.com>
* remote.c (get_remote_arch_state): New 'gdbarch' parameter. Use
it instead of target_gdbarch.
(get_remote_state, get_remote_packet_size): Adjust
get_remote_arch_state calls, passing down target_gdbarch
explicitly.
(packet_reg_from_regnum, packet_reg_from_pnum): New parameter
'gdbarch' and use it instead of target_gdbarch.
(get_memory_packet_size): Adjust get_remote_arch_state calls,
passing down target_gdbarch explicitly.
(struct stop_reply) <arch>: New field.
(remote_parse_stop_reply): Use the stopped thread's architecture,
not the current inferior's. Save the architecture in the
stop_reply.
(process_stop_reply): Use the stop reply's architecture.
(process_g_packet, remote_fetch_registers)
(remote_prepare_to_store, store_registers_using_G)
(remote_store_registers): Adjust get_remote_arch_state calls,
using the regcache's architecture.
(remote_get_trace_status): Adjust get_remote_arch_state calls,
passing down target_gdbarch explicitly.
* spu-multiarch.c (spu_thread_architecture): Defer to the target
beneath instead of calling target_gdbarch.
* target.c (default_thread_architecture): Use the specified
inferior's architecture, instead of the current inferior's
architecture (via target_gdbarch).
gdb/testsuite/ChangeLog:
2017-10-04 Pedro Alves <palves@redhat.com>
* gdb.multi/hangout.c: Include <unistd.h>.
(hangout_loop): New function.
(main): Call alarm. Call hangout_loop in a loop.
* gdb.multi/hello.c: Include <unistd.h>.
(hello_loop): New function.
(main): Call alarm. Call hangout_loop in a loop.
* gdb.multi/multi-arch.exp: Test running to a breakpoint one
inferior with the other selected.
This changes read_memory_robust to return a std::vector, allowing the
removal of free_memory_read_result_vector and associated cleanups.
This patch also changes the functions it touches to be a bit more
robust with regards to deallocation; it's perhaps possible that
read_memory_robust could have leaked in some situations.
This patch is based on my earlier series to remove some MI cleanups.
Regression tested by the buildbot.
gdb/ChangeLog
2017-09-29 Tom Tromey <tom@tromey.com>
* target.c (read_whatever_is_readable): Change type of "result".
Update.
(free_memory_read_result_vector): Remove.
(read_memory_robust): Change return type. Update.
* mi/mi-main.c (mi_cmd_data_read_memory_bytes): Update. Use
bin2hex, std::string.
* target.h (memory_read_result_s): Remove typedef.
(free_memory_read_result_vector): Remove.
(read_memory_robust): Return std::vector.
This removes make_cleanup_defer_target_commit_resume in favor of using
scoped_restore.
gdb/ChangeLog
2017-09-29 Tom Tromey <tom@tromey.com>
* target.h (make_scoped_defer_target_commit_resume): Update.
* target.c (make_scoped_defer_target_commit_resume): Rename from
make_cleanup_defer_target_commit_resume. Return a
scoped_restore.
* infrun.c (proceed): Use make_scoped_defer_target_commit_resume.
This adds two add_cmd overloads: one whose callback takes a const char *,
and one that doesn't accept a function at all. The no-function overload
was introduced to avoid ambiguity when NULL was passed as the function.
Long term the goal is for all commands to take const arguments, and
for the non-const variants to be removed entirely.
gdb/ChangeLog
2017-09-27 Tom Tromey <tom@tromey.com>
* cli/cli-decode.c (add_cmd, set_cmd_cfunc): New function
overloads.
(do_add_cmd): Rename from add_cmd. Don't call set_cmd_cfunc.
(do_const_cfunc): New function.
(cmd_cfunc_eq): New overload.
(cli_user_command_p): Check do_const_cfunc.
* cli/cli-decode.h (struct cmd_list_element) <function>: New field
const_cfunc.
* command.h (add_cmd): Add const overload and no-function
overload.
(set_cmd_cfunc): Add const overload.
(cmd_const_cfunc_ftype): Declare.
(cmd_cfunc_eq): Add const overload.
* breakpoint.c, cli-cmds.c, cli-dump.c, guile/scm-cmd.c,
python/py-cmd.c, target.c, tracepoint.c: Use no-function add_cmd
overload.
This patch adds a target method named `to_thread_handle_to_thread_info'.
It is intended to map a thread library specific thread handle (such as
pthread_t for the pthread library) to the corresponding GDB internal
thread_info struct (pointer).
An implementation is provided for Linux pthreads; see linux-thread-db.c.
gdb/ChangeLog:
* target.h (struct target_ops): Add to_thread_handle_to_thread_info.
(target_thread_handle_to_thread_info): Declare.
* target.c (target_thread_handle_to_thread_info): New function.
* target-delegates.c: Regenerate.
* gdbthread.h (find_thread_by_handle): Declare.
* thread.c (find_thread_by_handle): New function.
* linux-thread-db.c (thread_db_thread_handle_to_thread_info): New
function.
(init_thread_db_ops): Register thread_db_thread_handle_to_thread_info.
This changes more places to use ui_out_emit_tuple, removing cleanups.
ChangeLog
2017-09-09 Tom Tromey <tom@tromey.com>
* target.c (flash_erase_command): Use ui_out_emit_tuple.
* stack.c (print_frame): Use ui_out_emit_tuple.
* spu-tdep.c (info_spu_event_command): Use ui_out_emit_tuple.
(info_spu_mailbox_command, info_spu_dma_command)
(info_spu_proxydma_command): Likewise.
* mi/mi-main.c (mi_cmd_trace_frame_collected): Use
ui_out_emit_tuple, gdb::byte_vector, bin2hex.
* mi/mi-cmd-file.c (mi_cmd_file_list_shared_libraries): Use
ui_out_emit_tuple.
* breakpoint.c (print_it_watchpoint): Use ui_out_emit_tuple.
For some reason I ended up staring at some of the "int flags" in
btrace-related code, and I got confused because I had no clue what the
flags where supposed to indicate.
Fix that by using enum_flags, so that:
#1 - it's clear from the type what the flags are about, and
#2 - the compiler can catch mismatching mistakes
gdb/ChangeLog:
2017-09-04 Pedro Alves <palves@redhat.com>
* cli/cli-cmds.c (print_disassembly, disassemble_current_function)
(disassemble_command): Use gdb_disassembly_flags instead of bare
int.
* disasm.c (gdb_pretty_print_disassembler::pretty_print_insn)
(dump_insns, do_mixed_source_and_assembly_deprecated)
(do_mixed_source_and_assembly, do_assembly_only, gdb_disassembly):
Use gdb_disassembly_flags instead of bare int.
* disasm.h (DISASSEMBLY_SOURCE_DEPRECATED, DISASSEMBLY_RAW_INSN)
(DISASSEMBLY_OMIT_FNAME, DISASSEMBLY_FILENAME)
(DISASSEMBLY_OMIT_PC, DISASSEMBLY_SOURCE)
(DISASSEMBLY_SPECULATIVE): No longer macros. Instead they're...
(enum gdb_disassembly_flag): ... values of this new enumeration.
(gdb_disassembly_flags): Define.
(gdb_disassembly)
(gdb_pretty_print_disassembler::pretty_print_insn): Use it.
* mi/mi-cmd-disas.c (mi_cmd_disassemble): Use
gdb_disassembly_flags instead of bare int.
* record-btrace.c (btrace_insn_history)
(record_btrace_insn_history, record_btrace_insn_history_range)
(record_btrace_insn_history_from): Use gdb_disassembly_flags
instead of bare int.
* record.c (get_insn_history_modifiers, cmd_record_insn_history):
Use gdb_disassembly_flags instead of bare int.
* target-debug.h (target_debug_print_gdb_disassembly_flags):
Define.
* target-delegates.c: Regenerate.
* target.c (target_insn_history, target_insn_history_from)
(target_insn_history_range): Use gdb_disassembly_flags instead of
bare int.
* target.h: Include "disasm.h".
(struct target_ops) <to_insn_history, to_insn_history_from,
to_insn_history_range>: Use gdb_disassembly_flags instead of bare
int.
(target_insn_history, target_insn_history_from)
(target_insn_history_range): Use gdb_disassembly_flags instead of
bare int.
This patch introduces the use of various containers -- std::vector,
std::string, or gdb::byte_vector -- in several spots in gdb that were
using xmalloc and a cleanup.
ChangeLog
2017-08-03 Tom Tromey <tom@tromey.com>
* valops.c (search_struct_method): Use gdb::byte_vector.
* valarith.c (value_concat): Use std::vector.
* target.c (memory_xfer_partial): Use gdb::byte_vector.
(simple_search_memory): Likewise.
* printcmd.c (find_string_backward): Use gdb::byte_vector.
* mi/mi-main.c (mi_cmd_data_write_memory): Use gdb::byte_vector.
* gcore.c (gcore_copy_callback): Use gdb::byte_vector.
* elfread.c (elf_rel_plt_read): Use std::string.
* cp-valprint.c (cp_print_value): Use gdb::byte_vector.
* cli/cli-dump.c (restore_section_callback): Use
gdb::byte_vector.
Now that the to_fetch_registers, to_store_registers and
to_prepare_to_store target methods don't rely on the value of
inferior_ptid anymore, we can remove a bunch of now unnecessary setting
and restoring of inferior_ptid.
The asserts added recently in target_fetch_registers and
target_store_registers, which validate that inferior_ptid matches the
regcache's ptid, must go away. It's the whole point of this effort, to
not require inferior_ptid to have a particular value when calling these
functions.
One thing that I noticed is how sol-thread.c's ps_lgetregs and friends
use the current value of inferior_ptid instead of what's passed as
argument (ph->ptid), unlike proc-service.c's versions of the same
functions. Is it expected? I left it like this in the current patch,
but unless there's a good reason for it to be that way, I guess we
should make it use the parameter.
gdb/ChangeLog:
* fbsd-tdep.c (fbsd_corefile_thread): Don't set/restore
inferior_ptid.
* proc-service.c (ps_lgetregs, ps_lsetregs, ps_lgetfpregs,
ps_lsetfpregs): Likewise.
* regcache.c (regcache_raw_update, regcache_raw_write): Likewise.
* sol-thread.c (ps_lgetregs, ps_lsetregs, ps_lgetfpregs,
ps_lsetfpregs): Likewise.
* target.c (target_fetch_registers, target_store_registers):
Remove asserts.
We are currently assuming that regcache->ptid is equal to inferior_ptid
when we call target_fetch/store_registers. These asserts just validate
that assumption. Also, since the following patches will change target
code to use regcache->ptid instead of inferior_ptid, asserting that they
are the same should ensure that our changes don't have any unintended
consequences.
gdb/ChangeLog:
* target.c (target_fetch_registers, target_store_registers): Add
assert.
Changes in v4:
- Replaced phex call with hex_string.
Changes in v3:
- Addressed comments by Pedro.
- Output of memory region size now in hex format.
- Misc formatting fixups.
- Addressed Simon's comments on formatting.
- Adjusted command text in the manual entry.
- Fixed up ChangeLog.
- Renamed flash_erase_all_command to flash_erase_command.
Changes in v2:
- Added NEWS entry.
- Fixed long lines.
- Address printing with paddress.
Years ago we contributed flash programming patches upstream. The following
patch is a leftover one that complements that functionality by adding a new
command to erase all reported flash memory blocks.
The command is most useful when we're dealing with flash-enabled targets
(mostly bare-metal) and we need to reset the board for some reason.
The wiping out of flash memory regions should help the target come up with a
known clean state from which the user can load a new image and resume
debugging. It is convenient enough to do this from the debugger, and there is
also an MI command to expose this functionality to the IDE's.
gdb/doc/ChangeLog:
2017-01-20 Mike Wrighton <mike_wrighton@codesourcery.com>
Luis Machado <lgustavo@codesourcery.com>
* gdb.texinfo (-target-flash-erase): New MI command description.
(flash-erase): New CLI command description.
gdb/ChangeLog:
2017-01-20 Mike Wrighton <mike_wrighton@codesourcery.com>
Luis Machado <lgustavo@codesourcery.com>
* NEWS (New commands): Mention flash-erase.
(New MI commands): Mention target-flash-erase.
* mi/mi-cmds.c (mi_cmd_target_flash_erase): Add target-flash-erase MI
command.
* mi/mi-cmds.h (mi_cmd_target_flash_erase): New declaration.
* mi/mi-main.c (mi_cmd_target_flash_erase): New function.
* target.c (flash_erase_command): New function.
(initialize_targets): Add new flash-erase command.
* target.h (flash_erase_command): New declaration.
This applies the second part of GDB's End of Year Procedure, which
updates the copyright year range in all of GDB's files.
gdb/ChangeLog:
Update copyright year range in all GDB files.
Currently, with "maint set target-non-stop on", that is, when gdb
connects with the non-stop/asynchronous variant of the remote
protocol, even with "set non-stop off", GDB always sends one vCont
packet per thread resumed. This patch makes GDB aggregate and
coalesce vCont packets, so we send vCont packets like "vCont;s:p1.1;c"
in non-stop mode too.
Basically, this is done by:
- Adding a new target method target_commit_resume that is called
after calling target_resume one or more times. When resuming a
batch of threads, we'll only call target_commit_resume once after
calling target_resume for all threads.
- Making the remote target defer sending the actual vCont packet to
target_commit_resume.
Special care must be taken to avoid sending a vCont action with a
"wildcard" thread-id (all threads of process / all threads) when that
would resume threads/processes that should not be resumed. See
remote_commit_resume comments for details.
Unlike all-stop's remote_resume implementation, this handles the case
of too many actions resulting in a too-big vCont packet, by flushing
the vCont packet and starting a new one.
E.g., imagining that the "c" action in:
vCont;s:1;c
overflows the packet buffer, we split the actions like:
vCont;s:1
vCont;c
Tested on x86_64 Fedora 20, with and without "maint set
target-non-stop on".
Also tested with a hack that makes remote_commit_resume flush the vCont
packet after every action appended (which caught a few bugs).
gdb/ChangeLog:
2016-10-26 Pedro Alves <palves@redhat.com>
* inferior.h (ALL_NON_EXITED_INFERIORS): New macro.
* infrun.c (do_target_resume): Call target_commit_resume.
(proceed): Defer target_commit_resume while looping over threads,
resuming them. Call target_commit_resume at the end.
* record-btrace.c (record_btrace_commit_resume): New function.
(init_record_btrace_ops): Install it as to_commit_resume method.
* record-full.c (record_full_commit_resume): New function.
(record_full_wait_1): Call the beneath target's to_commit_resume
method.
(init_record_full_ops): Install record_full_commit_resume as
to_commit_resume method.
* remote.c (struct private_thread_info) <last_resume_step,
last_resume_sig, vcont_resumed>: New fields.
(remote_add_thread): Set the new thread's vcont_resumed flag.
(demand_private_info): Delete.
(get_private_info_thread, get_private_info_ptid): New functions.
(remote_update_thread_list): Adjust.
(process_initial_stop_replies): Clear the thread's vcont_resumed
flag.
(remote_resume): If connected in non-stop mode, record the resume
request and return early.
(struct private_inferior): New.
(struct vcont_builder): New.
(vcont_builder_restart, vcont_builder_flush)
(vcont_builder_push_action): New functions.
(MAX_ACTION_SIZE): New macro.
(remote_commit_resume): New function.
(thread_pending_fork_status, is_pending_fork_parent_thread): New
functions.
(check_pending_event_prevents_wildcard_vcont_callback)
(check_pending_events_prevent_wildcard_vcont): New functions.
(process_stop_reply): Adjust. Clear the thread's vcont_resumed
flag.
(init_remote_ops): Install remote_commit_resume.
* target-delegates.c: Regenerate.
* target.c (defer_target_commit_resume): New global.
(target_commit_resume, make_cleanup_defer_target_commit_resume):
New functions.
* target.h (struct target_ops) <to_commit_resume>: New field.
(target_resume): Update comments.
(target_commit_resume): New declaration.
This simple commit consolidates the API of
target_supports_multi_process. Since both GDB and gdbserver use the
same function prototype, all that was needed was to move create this
prototype on gdb/target/target.h and turn the macros declared on
gdb/{,gdbserver/}target.h into actual functions.
Regtested (clean pass) on the BuildBot.
gdb/ChangeLog:
2016-10-06 Sergio Durigan Junior <sergiodj@redhat.com>
* target.c (target_supports_multi_process): New function, moved
from...
* target.h (target_supports_multi_process): ... here. Remove
macro.
* target/target.h (target_supports_multi_process): New prototype.
gdb/gdbserver/ChangeLog:
2016-10-06 Sergio Durigan Junior <sergiodj@redhat.com>
* target.c (target_supports_multi_process): New function, moved
from...
* target.h (target_supports_multi_process): ... here. Remove
macro.
This patch consolidates the API of target_mourn_inferior between GDB
and gdbserver, in my continuing efforts to make sharing the
fork_inferior function possible between both.
GDB's version of the function did not care about the inferior's ptid
being mourned, but gdbserver's needed to know this information. Since
it actually makes sense to pass the ptid as an argument, instead of
depending on a global value directly (which GDB's version did), I
decided to make the generic API to accept it. I then went on and
extended all calls being made on GDB to include a ptid argument (which
ended up being inferior_ptid most of the times, anyway), and now we
have a more sane interface.
On GDB's side, after talking to Pedro a bit about it, we decided that
just an assertion to make sure that the ptid being passed is equal to
inferior_ptid would be enough for now, on the GDB side. We can remove
the assertion and perform more operations later if we ever pass
anything different than inferior_ptid.
Regression tested on our BuildBot, everything OK.
I'd appreciate a special look at gdb/windows-nat.c's modification
because I wasn't really sure what to do there. It seemed to me that
maybe I should build a ptid out of the process information there, but
then I am almost sure the assertion on GDB's side would trigger.
gdb/ChangeLog:
2016-09-19 Sergio Durigan Junior <sergiodj@redhat.com>
* darwin-nat.c (darwin_kill_inferior): Adjusting call to
target_mourn_inferior to include ptid_t argument.
* fork-child.c (startup_inferior): Likewise.
* gnu-nat.c (gnu_kill_inferior): Likewise.
* inf-ptrace.c (inf_ptrace_kill): Likewise.
* infrun.c (handle_inferior_event_1): Likewise.
* linux-nat.c (linux_nat_attach): Likewise.
(linux_nat_kill): Likewise.
* nto-procfs.c (interrupt_query): Likewise.
(procfs_interrupt): Likewise.
(procfs_kill_inferior): Likewise.
* procfs.c (procfs_kill_inferior): Likewise.
* record.c (record_mourn_inferior): Likewise.
* remote-sim.c (gdbsim_kill): Likewise.
* remote.c (remote_detach_1): Likewise.
(remote_kill): Likewise.
* target.c (target_mourn_inferior): Change declaration to accept
new ptid_t argument; use gdb_assert on it.
* target.h (target_mourn_inferior): Move function prototype from
here...
* target/target.h (target_mourn_inferior): ... to here. Adjust it
to accept new ptid_t argument.
* windows-nat.c (get_windows_debug_event): Adjusting call to
target_mourn_inferior to include ptid_t argument.
gdb/gdbserver/ChangeLog:
2016-09-19 Sergio Durigan Junior <sergiodj@redhat.com>
* server.c (start_inferior): Call target_mourn_inferior instead of
mourn_inferior; pass ptid_t argument to it.
(resume): Likewise.
(handle_target_event): Likewise.
* target.c (target_mourn_inferior): New function.
* target.h (mourn_inferior): Delete macro.
Building on a 32-bit host fails currently with errors like:
.../src/gdb/exec.c: In function ‘target_xfer_status section_table_read_available_memory(gdb_byte*, ULONGEST, ULONGEST, ULONGEST*)’:
.../src/gdb/exec.c:801:54: error: no matching function for call to ‘min(ULONGEST, long unsigned int)’
end = std::min (offset + len, r->start + r->length);
^
In file included from /usr/include/c++/5.3.1/algorithm:61:0,
from .../src/gdb/exec.c:46:
/usr/include/c++/5.3.1/bits/stl_algobase.h:195:5: note: candidate: template<class _Tp> const _Tp& std::min(const _Tp&, const _Tp&)
min(const _Tp& __a, const _Tp& __b)
^
/usr/include/c++/5.3.1/bits/stl_algobase.h:195:5: note: template argument deduction/substitution failed:
.../src/gdb/exec.c:801:54: note: deduced conflicting types for parameter ‘const _Tp’ (‘long long unsigned int’ and ‘long unsigned int’)
end = std::min (offset + len, r->start + r->length);
^
In file included from /usr/include/c++/5.3.1/algorithm:61:0,
from .../src/gdb/exec.c:46:
/usr/include/c++/5.3.1/bits/stl_algobase.h:243:5: note: candidate: template<class _Tp, class _Compare> const _Tp& std::min(const _Tp&, const _Tp&, _Compare)
min(const _Tp& __a, const _Tp& __b, _Compare __comp)
^
The problem is that the std::min/std::max function templates use the
same type for both parameters. When the argument types are different,
the compiler can't automatically deduce which template specialization
to pick from the arguments' types.
Fix that by specifying the specialization we want explicitly.
gdb/ChangeLog:
2016-09-18 Pedro Alves <palves@redhat.com>
* breakpoint.c (hardware_watchpoint_inserted_in_range): Explicitly
specify the std:min/std::max specialization.
* exec.c (section_table_read_available_memory): Likewise.
* remote.c (remote_read_qxfer): Likewise.
* target.c (simple_verify_memory): Likewise.
This commit moves the target_wait prototype from the GDB-specific
target.h header to the common target/target.h header. Then, it
creates a compatible implementation of target_wait on gdbserver using
the_target->wait, and adjusts the (only) caller (mywait function).
Pretty straightforward, no regressions introduced.
gdb/gdbserver/ChangeLog:
2016-09-01 Sergio Durigan Junior <sergiodj@redhat.com>
* target.c (mywait): Call target_wait instead of
the_target->wait.
(target_wait): New function.
gdb/ChangeLog:
2016-09-01 Sergio Durigan Junior <sergiodj@redhat.com>
* target.c (target_wait): Mention that the function's prototype
can be found at target/target.h.
* target.h (target_wait): Move prototype from here...
* target/target.h (target_wait): ... to here.
This commit implements a new function, target_continue, on top of the
target_resume function. Then, it replaces all calls to target_resume
by calls to target_continue or to the already existing
target_continue_no_signal.
This is one of the (many) necessary steps needed to consolidate the
target interface between GDB and gdbserver. In particular, I am
interested in the impact this change will have on the unification of
the fork_inferior function (which I have been working on).
Tested on the BuildBot, no regressions introduced.
gdb/gdbserver/ChangeLog:
2016-09-31 Sergio Durigan Junior <sergiodj@redhat.com>
* server.c (start_inferior): New variable 'ptid'. Replace calls
to the_target->resume by target_continue{,_no_signal}, depending
on the case.
* target.c (target_stop_and_wait): Call target_continue_no_signal
instead of the_target->resume.
(target_continue): New function.
gdb/ChangeLog:
2016-09-31 Sergio Durigan Junior <sergiodj@redhat.com>
* fork-child.c (startup_inferior): Replace calls to target_resume
by target_continue{,_no_signal}, depending on the case.
* linux-nat.c (cleanup_target_stop): Call
target_continue_no_signal instead of target_resume.
* procfs.c (procfs_wait): Likewise.
* target.c (target_continue): New function.
* target/target.h (target_continue): New prototype.
When executing commands on a secondary UI running the MI interpreter,
some commands that should be synchronous are not. MI incorrectly
continues processing input right after the synchronous command is
sent, before the target stops.
The problem happens when we emit MI async events (=library-loaded,
etc.), and we go about restoring the previous terminal state, we end
up calling target_terminal_ours, which incorrectly always installs the
current UI's input_fd in the event loop... That is, code like this:
old_chain = make_cleanup_restore_target_terminal ();
target_terminal_ours_for_output ();
fprintf_unfiltered (mi->event_channel, "library-loaded");
...
do_cleanups (old_chain);
The fix is to move the add_file_handler/delete_file_handler calls out
of target_terminal_$foo, making these completely no-ops unless called
with the main UI as current UI.
gdb/ChangeLog:
2016-08-09 Pedro Alves <palves@redhat.com>
PR gdb/20418
* event-top.c (ui_register_input_event_handler)
(ui_unregister_input_event_handler): New functions.
(async_enable_stdin): Register input in the event loop.
(async_disable_stdin): Unregister input from the event loop.
(gdb_setup_readline): Register input in the event loop.
* infrun.c (check_curr_ui_sync_execution_done): Register input in
the event loop.
* target.c (target_terminal_inferior): Don't unregister input from
the event loop.
(target_terminal_ours): Don't register input in the event loop.
* target.h (target_terminal_inferior)
(target_terminal_ours_for_output, target_terminal_ours): Update
comments.
* top.h (ui_register_input_event_handler)
(ui_unregister_input_event_handler): New declarations.
* utils.c (ui_unregister_input_event_handler_cleanup)
(prepare_to_handle_input): New functions.
(defaulted_query, prompt_for_continue): Use
prepare_to_handle_input.
gdb/testsuite/ChangeLog:
2016-08-09 Pedro Alves <palves@redhat.com>
Simon Marchi <simon.marchi@ericsson.com>
PR gdb/20418
* gdb.mi/new-ui-mi-sync.c, gdb.mi/new-ui-mi-sync.exp: New files.
* lib/mi-support.exp (mi_expect_interrupt): Remove anchors.
Some analysis we did here showed that increasing the cap on the
transfer size in target.c:memory_xfer_partial could give 20% or more
improvement in remote load across JTAG. Transfer sizes were capped
to 4K bytes because of performance problems encountered with the
restore command, documented here:
https://sourceware.org/ml/gdb-patches/2013-07/msg00611.html
and in commit 67c059c29e ("Improve performance of large restore
commands").
The 4K cap was introduced because in a case where the restore command
requested a 100MB transfer, memory_xfer_partial would repeatedy
allocate and copy an entire 100MB buffer in order to properly handle
breakpoint shadow instructions, even though memory_xfer_partial would
actually only write a small portion of the buffer contents.
A couple of alternative solutions were suggested:
* change the algorithm for handling the breakpoint shadow instructions
* throttle the transfer size up or down based on the previous actual
transfer size
I tried implementing the throttling approach, and my implementation
reduced the performance in some cases.
This patch implements a new target function that returns that target's
limit on memory transfer size. It defaults to ULONGEST_MAX bytes,
because for native targets there is no marshaling and thus no limit is
needed. For remote targets it uses get_memory_write_packet_size.
gdb/ChangeLog:
* remote.c (remote_get_memory_xfer_limit): New function.
* target-delegates.c: Regenerate.
* target.c (memory_xfer_partial): Call
target_ops.to_get_memory_xfer_limit.
* target.h (struct target_ops)
<to_get_memory_xfer_limit>: New member.
Several targets have a copy of the same code that prints
"Detaching from program ..."
in their target_detach implementation. Factor that out to a common
function.
(For now, I left the couple targets that print this a bit differently
alone. Maybe this could be further pulled out into infcmd.c. If we
did that, and those targets want to continue printing differently,
this new function could be converted to a target method.)
gdb/ChangeLog:
2016-07-01 Pedro Alves <palves@redhat.com>
* darwin-nat.c (darwin_detach): Use target_announce_detach.
* inf-ptrace.c (inf_ptrace_detach): Likewise.
* nto-procfs.c (procfs_detach): Likewise.
* remote.c (remote_detach_1): Likewise.
* target.c (target_announce_detach): New function.
* target.h (target_announce_detach): New declaration.
PR gdb/17210 concerns a possible memory leak in read_memory_robust.
The bug can happen because read_memory_robust allocates memory, does
not install any cleanups, and invokes QUIT. Similarly, target_read
calls QUIT, so it too can potentially throw.
The fix is to install cleanups to guard the allocated memory.
Built and regtested on x86-64 Fedora 23. I couldn't think of a way to
test this, so no new test; and of course this means it should have
more careful review.
2016-06-29 Tom Tromey <tom@tromey.com>
PR gdb/17210:
* target.c (free_memory_read_result_vector): Take a pointer to the
VEC as an argument.
(read_memory_robust): Install a cleanup for "result".
* mi/mi-main.c (mi_cmd_data_read_memory_bytes): Update.
When sync_execution (a boolean) is true, it means we're running a
foreground command -- we hide the prompt stop listening to input, give
the inferior the terminal, then go to the event loop waiting for the
target to stop.
With multiple independent UIs, we need to track whether each UI is
synchronously blocked waiting for the target. IOW, if you do
"continue" in one console, that console stops accepting commands, but
you should still be free to type other commands in the others
consoles.
Just simply making sync_execution be per-UI alone not sufficient,
because of this in fetch_inferior_event:
/* If the inferior was in sync execution mode, and now isn't,
restore the prompt (a synchronous execution command has finished,
and we're ready for input). */
if (current_ui->async && was_sync && !sync_execution)
observer_notify_sync_execution_done ();
We'd have to record at entry the "was_sync" state for each UI, not
just of the current UI.
This patch instead replaces the sync_execution flag by a per-UI
tristate flag indicating the command line prompt state:
enum prompt_state
{
/* The command line is blocked simulating synchronous execution.
This is used to implement the foreground execution commands
('run', 'continue', etc.). We won't display the prompt and
accept further commands until the execution is actually over. */
PROMPT_BLOCKED,
/* The command finished; display the prompt before returning back to
the top level. */
PROMPT_NEEDED,
/* We've displayed the prompt already, ready for input. */
PROMPTED,
;
I think the end result is _much_ clearer than the current code, and,
it addresses the original motivation too.
gdb/ChangeLog:
2016-06-21 Pedro Alves <palves@redhat.com>
* annotate.c: Include top.h.
(async_background_execution_p): Delete.
(print_value_flags): Check the UI's prompt state rather then
async_background_execution_p.
* event-loop.c (start_event_loop): Set the prompt state to
PROMPT_NEEDED.
* event-top.c (display_gdb_prompt, async_enable_stdin)
(async_disable_stdin): Check the current UI's prompt state instead
of the sync_execution global.
(command_line_handler): Set the prompt state to PROMPT_NEEDED
before running a command, and display the prompt if still needed
afterwards.
* infcall.c (struct call_thread_fsm) <waiting_ui>: New field.
(new_call_thread_fsm): New parameter 'waiting_ui'. Store it.
(call_thread_fsm_should_stop): Set the prompt state to
PROMPT_NEEDED.
(run_inferior_call): Adjust to temporarily set the prompt state to
PROMPT_BLOCKED instead of using the sync_execution global.
(call_function_by_hand_dummy): Pass the current UI to
new_call_thread_fsm.
* infcmd.c: Include top.h.
(continue_1): Check the current UI's prompt state instead of the
sync_execution global.
(continue_command): Validate global execution state before calling
prepare_execution_command.
(step_1): Call all_uis_check_sync_execution_done.
(attach_post_wait): Don't call async_enable_stdin here. Remove
reference to sync_execution.
* infrun.c (sync_execution): Delete global.
(follow_fork_inferior)
(reinstall_readline_callback_handler_cleanup): Check the current
UI's prompt state instead of the sync_execution global.
(check_curr_ui_sync_execution_done)
(all_uis_check_sync_execution_done): New functions.
(fetch_inferior_event): Call all_uis_check_sync_execution_done
instead of trying to determine whether the global sync execution
changed.
(handle_no_resumed): Check the prompt state of all UIs.
(normal_stop): Emit the no unwait-for even to all PROMPT_BLOCKED
UIs. Emit the "Switching to" notification to all UIs. Enable
stdin in all UIs.
* infrun.h (sync_execution): Delete.
(all_uis_check_sync_execution_done): Declare.
* main.c (captured_command_loop): Don't call
interp_pre_command_loop if the prompt is blocked.
(catch_command_errors, catch_command_errors_const): Adjust.
(captured_main): Set the initial prompt state to PROMPT_NEEDED.
* mi/mi-interp.c (display_mi_prompt): Set the prompt state to
PROMPTED.
(mi_interpreter_resume): Don't clear sync_execution. Remove hack
comment.
(mi_execute_command_input_handler): Set the prompt state to
PROMPT_NEEDED before executing the command, and only display the
prompt if the prompt state is PROMPT_NEEDED afterwards.
(mi_on_resume_1): Adjust to check the prompt state.
* target.c (target_terminal_inferior): Adjust to check the prompt
state.
* top.c (wait_sync_command_done, maybe_wait_sync_command_done)
(execute_command): Check the current UI's prompt state instead of
sync_execution.
* top.h (enum prompt_state): New.
(struct ui) <prompt_state>: New field.
(ALL_UIS): New macro.
Since we always run the inferior in the main console (unless "set
inferior-tty" is in effect), when some UI other than the main one
calls target_terminal_inferior/target_terminal_inferior, then we only
register/unregister the UI's input from the event loop, but leave the
main UI's terminal settings as is.
gdb/ChangeLog:
2016-06-21 Pedro Alves <palves@redhat.com>
* target.c (target_terminal_inferior): Bail out after
unregistering input_fd if not on the main UI.
(target_terminal_ours): Bail out after registering input_fd if not
on the main UI.
(target_terminal_ours_for_output): Bail out if not on the main UI.
And with that, we can switch the current UI to the UI whose input
descriptor woke up the event loop. IOW, if the user types in UI 2,
the event loop wakes up, switches to UI 2, and processes the input.
Next the user types in UI 3, the event loop wakes up and switches to
UI 3, etc.
gdb/ChangeLog:
2016-06-21 Pedro Alves <palves@redhat.com>
* event-top.c (input_fd): Delete.
(stdin_event_handler): Switch to the UI whose input descriptor got
the event. Adjust to per-UI input_fd.
(gdb_setup_readline): Don't set the input_fd global. Adjust to
per-UI input_fd.
(gdb_disable_readline): Adjust to per-UI input_fd.
* event-top.h (input_fd): Delete declaration.
* linux-nat.c (linux_nat_terminal_inferior): Don't remove input_fd
from the event-loop here.
(linux_nat_terminal_ours): Don't register input_fd in the
event-loop here.
* main.c (captured_main): Adjust to per-UI input_fd.
* remote.c (remote_terminal_inferior): Don't remove input_fd from
the event-loop here.
(remote_terminal_ours): Don't register input_fd in the event-loop
here.
* target.c: Include top.h and event-top.h.
(target_terminal_inferior): Remove input_fd from the event-loop
here.
(target_terminal_ours): Register input_fd in the event-loop.
* top.h (struct ui) <input_fd>: New field.
If the user presses Ctrl-C immediately before target_terminal_inferior
is called and the target is resumed, instead of after, the Ctrl-C ends
up pending in the quit flag until the target next stops.
remote.c has this bit to handle this:
if (!target_is_async_p ())
{
ofunc = signal (SIGINT, sync_remote_interrupt);
/* If the user hit C-c before this packet, or between packets,
pretend that it was hit right here. */
if (check_quit_flag ())
sync_remote_interrupt (SIGINT);
}
But that's only reachable if async is off, while async is on by
default nowadays. It's also obviously not reacheable on native
targets.
This patch generalizes that to all targets.
We can't remove that remote.c bit yet, until we get rid of the sync
SIGINT handler though. That'll be done later in the series.
gdb/ChangeLog:
2016-04-12 Pedro Alves <palves@redhat.com>
* remote.c (remote_pass_ctrlc): New function.
(init_remote_ops): Install it.
* target.c (target_terminal_inferior): Pass pending Ctrl-C to the
target.
(target_pass_ctrlc, default_target_pass_ctrlc): New functions.
* target.h (struct target_ops) <to_pass_ctrlc>: New method.
(target_pass_ctrlc, default_target_pass_ctrlc): New declarations.
* target-delegates.c: Regenerate.
This commit changes GDB to track thread numbers per-inferior. Then,
if you're debugging multiple inferiors, GDB displays
"inferior-num.thread-num" instead of just "thread-num" whenever it
needs to display a thread:
(gdb) info inferiors
Num Description Executable
1 process 6022 /home/pedro/gdb/tests/threads
* 2 process 6037 /home/pedro/gdb/tests/threads
(gdb) info threads
Id Target Id Frame
1.1 Thread 0x7ffff7fc2740 (LWP 6022) "threads" (running)
1.2 Thread 0x7ffff77c0700 (LWP 6028) "threads" (running)
1.3 Thread 0x7ffff7fc2740 (LWP 6032) "threads" (running)
2.1 Thread 0x7ffff7fc1700 (LWP 6037) "threads" (running)
2.2 Thread 0x7ffff77c0700 (LWP 6038) "threads" (running)
* 2.3 Thread 0x7ffff7fc2740 (LWP 6039) "threads" (running)
(gdb)
...
(gdb) thread 1.1
[Switching to thread 1.1 (Thread 0x7ffff7fc2740 (LWP 8155))]
(gdb)
...
etc.
You can still use "thread NUM", in which case GDB infers you're
referring to thread NUM of the current inferior.
The $_thread convenience var and Python's InferiorThread.num attribute
are remapped to the new per-inferior thread number. It's a backward
compatibility break, but since it only matters when debugging multiple
inferiors, I think it's worth doing.
Because MI thread IDs need to be a single integer, we keep giving
threads a global identifier, _in addition_ to the per-inferior number,
and make MI always refer to the global thread IDs. IOW, nothing
changes from a MI frontend's perspective.
Similarly, since Python's Breakpoint.thread and Guile's
breakpoint-thread/set-breakpoint-thread breakpoint methods need to
work with integers, those are adjusted to work with global thread IDs
too. Follow up patches will provide convenient means to access
threads' global IDs.
To avoid potencially confusing users (which also avoids updating much
of the testsuite), if there's only one inferior and its ID is "1",
IOW, the user hasn't done anything multi-process/inferior related,
then the "INF." part of thread IDs is not shown. E.g,.:
(gdb) info inferiors
Num Description Executable
* 1 process 15275 /home/pedro/gdb/tests/threads
(gdb) info threads
Id Target Id Frame
* 1 Thread 0x7ffff7fc1740 (LWP 15275) "threads" main () at threads.c:40
(gdb) add-inferior
Added inferior 2
(gdb) info threads
Id Target Id Frame
* 1.1 Thread 0x7ffff7fc1740 (LWP 15275) "threads" main () at threads.c:40
(gdb)
No regressions on x86_64 Fedora 20.
gdb/ChangeLog:
2016-01-13 Pedro Alves <palves@redhat.com>
* NEWS: Mention that thread IDs are now per inferior and global
thread IDs.
* Makefile.in (SFILES): Add tid-parse.c.
(COMMON_OBS): Add tid-parse.o.
(HFILES_NO_SRCDIR): Add tid-parse.h.
* ada-tasks.c: Adjust to use ptid_to_global_thread_id.
* breakpoint.c (insert_breakpoint_locations)
(remove_threaded_breakpoints, bpstat_check_breakpoint_conditions)
(print_one_breakpoint_location, set_longjmp_breakpoint)
(check_longjmp_breakpoint_for_call_dummy)
(set_momentary_breakpoint): Adjust to use global IDs.
(find_condition_and_thread, watch_command_1): Use parse_thread_id.
(until_break_command, longjmp_bkpt_dtor)
(breakpoint_re_set_thread, insert_single_step_breakpoint): Adjust
to use global IDs.
* dummy-frame.c (pop_dummy_frame_bpt): Adjust to use
ptid_to_global_thread_id.
* elfread.c (elf_gnu_ifunc_resolver_stop): Likewise.
* gdbthread.h (struct thread_info): Rename field 'num' to
'global_num. Add new fields 'per_inf_num' and 'inf'.
(thread_id_to_pid): Rename thread_id_to_pid to
global_thread_id_to_ptid.
(pid_to_thread_id): Rename to ...
(ptid_to_global_thread_id): ... this.
(valid_thread_id): Rename to ...
(valid_global_thread_id): ... this.
(find_thread_id): Rename to ...
(find_thread_global_id): ... this.
(ALL_THREADS, ALL_THREADS_BY_INFERIOR): Declare.
(print_thread_info): Add comment.
* tid-parse.h: New file.
* tid-parse.c: New file.
* infcmd.c (step_command_fsm_prepare)
(step_command_fsm_should_stop): Adjust to use the global thread
ID.
(until_next_command, until_next_command)
(finish_command_fsm_should_stop): Adjust to use the global thread
ID.
(attach_post_wait): Adjust to check the inferior number too.
* inferior.h (struct inferior) <highest_thread_num>: New field.
* infrun.c (handle_signal_stop)
(insert_exception_resume_breakpoint)
(insert_exception_resume_from_probe): Adjust to use the global
thread ID.
* record-btrace.c (record_btrace_open): Use global thread IDs.
* remote.c (process_initial_stop_replies): Also consider the
inferior number.
* target.c (target_pre_inferior): Clear the inferior's highest
thread num.
* thread.c (clear_thread_inferior_resources): Adjust to use the
global thread ID.
(new_thread): New inferior parameter. Adjust to use it. Set both
the thread's global ID and the thread's per-inferior ID.
(add_thread_silent): Adjust.
(find_thread_global_id): New.
(find_thread_id): Make static. Adjust to rename.
(valid_thread_id): Rename to ...
(valid_global_thread_id): ... this.
(pid_to_thread_id): Rename to ...
(ptid_to_global_thread_id): ... this.
(thread_id_to_pid): Rename to ...
(global_thread_id_to_ptid): ... this. Adjust.
(first_thread_of_process): Adjust.
(do_captured_list_thread_ids): Adjust to use global thread IDs.
(should_print_thread): New function.
(print_thread_info): Rename to ...
(print_thread_info_1): ... this, and add new show_global_ids
parameter. Handle it. Iterate over inferiors.
(print_thread_info): Reimplement as wrapper around
print_thread_info_1.
(show_inferior_qualified_tids): New function.
(print_thread_id): Use it.
(tp_array_compar): Compare inferior numbers too.
(thread_apply_command): Use tid_range_parser.
(do_captured_thread_select): Use parse_thread_id.
(thread_id_make_value): Adjust.
(_initialize_thread): Adjust "info threads" help string.
* varobj.c (struct varobj_root): Update comment.
(varobj_create): Adjust to use global thread IDs.
(value_of_root_1): Adjust to use global_thread_id_to_ptid.
* windows-tdep.c (display_tib): No longer accept an argument.
* cli/cli-utils.c (get_number_trailer): Make extern.
* cli/cli-utils.h (get_number_trailer): Declare.
(get_number_const): Adjust documentation.
* mi/mi-cmd-var.c (mi_cmd_var_update_iter): Adjust to use global
thread IDs.
* mi/mi-interp.c (mi_new_thread, mi_thread_exit)
(mi_on_normal_stop, mi_output_running_pid, mi_on_resume):
* mi/mi-main.c (mi_execute_command, mi_cmd_execute): Likewise.
* guile/scm-breakpoint.c (gdbscm_set_breakpoint_thread_x):
Likewise.
* python/py-breakpoint.c (bppy_set_thread): Likewise.
* python/py-finishbreakpoint.c (bpfinishpy_init): Likewise.
* python/py-infthread.c (thpy_get_num): Add comment and return the
per-inferior thread ID.
(thread_object_getset): Update comment of "num".
gdb/testsuite/ChangeLog:
2016-01-07 Pedro Alves <palves@redhat.com>
* gdb.base/break.exp: Adjust to output changes.
* gdb.base/hbreak2.exp: Likewise.
* gdb.base/sepdebug.exp: Likewise.
* gdb.base/watch_thread_num.exp: Likewise.
* gdb.linespec/keywords.exp: Likewise.
* gdb.multi/info-threads.exp: Likewise.
* gdb.threads/thread-find.exp: Likewise.
* gdb.multi/tids.c: New file.
* gdb.multi/tids.exp: New file.
gdb/doc/ChangeLog:
2016-01-07 Pedro Alves <palves@redhat.com>
* gdb.texinfo (Threads): Document per-inferior thread IDs,
qualified thread IDs, global thread IDs and thread ID lists.
(Set Watchpoints, Thread-Specific Breakpoints): Adjust to refer to
thread IDs.
(Convenience Vars): Document the $_thread convenience variable.
(Ada Tasks): Adjust to refer to thread IDs.
(GDB/MI Async Records, GDB/MI Thread Commands, GDB/MI Ada Tasking
Commands, GDB/MI Variable Objects): Update to mention global
thread IDs.
* guile.texi (Breakpoints In Guile)
<breakpoint-thread/set-breakpoint-thread breakpoint>: Mention
global thread IDs instead of thread IDs.
* python.texi (Threads In Python): Adjust documentation of
InferiorThread.num.
(Breakpoint.thread): Mention global thread IDs instead of thread
IDs.
I see a timeout in gdb.base/random-signal.exp,
Continuing.^M
PASS: gdb.base/random-signal.exp: continue
^CPython Exception <type 'exceptions.KeyboardInterrupt'> <type
exceptions.KeyboardInterrupt'>: ^M
FAIL: gdb.base/random-signal.exp: stop with control-c (timeout)
it can be reproduced by running random-signal.exp with native-gdbserver
in a loop, like this, and the fail will be shown in about 20 runs,
$ (set -e; while true; do make check RUNTESTFLAGS="--target_board=native-gdbserver random-signal.exp"; done)
In the test, the program is being single-stepped for software watchpoint,
and in each internal stop, python unwinder sniffer is used,
#0 pyuw_sniffer (self=<optimised out>, this_frame=<optimised out>, cache_ptr=0xd554f8) at /home/yao/SourceCode/gnu/gdb/git/gdb/python/py-unwind.c:608
#1 0x00000000006a10ae in frame_unwind_try_unwinder (this_frame=this_frame@entry=0xd554e0, this_cache=this_cache@entry=0xd554f8, unwinder=0xecd540)
at /home/yao/SourceCode/gnu/gdb/git/gdb/frame-unwind.c:107
#2 0x00000000006a143f in frame_unwind_find_by_frame (this_frame=this_frame@entry=0xd554e0, this_cache=this_cache@entry=0xd554f8)
at /home/yao/SourceCode/gnu/gdb/git/gdb/frame-unwind.c:163
#3 0x000000000069dc6b in compute_frame_id (fi=0xd554e0) at /home/yao/SourceCode/gnu/gdb/git/gdb/frame.c:454
#4 get_prev_frame_if_no_cycle (this_frame=this_frame@entry=0xd55410) at /home/yao/SourceCode/gnu/gdb/git/gdb/frame.c:1781
#5 0x000000000069fdb9 in get_prev_frame_always_1 (this_frame=0xd55410) at /home/yao/SourceCode/gnu/gdb/git/gdb/frame.c:1955
#6 get_prev_frame_always (this_frame=this_frame@entry=0xd55410) at /home/yao/SourceCode/gnu/gdb/git/gdb/frame.c:1971
#7 0x00000000006a04b1 in get_prev_frame (this_frame=this_frame@entry=0xd55410) at /home/yao/SourceCode/gnu/gdb/git/gdb/frame.c:2213
when GDB goes to python extension, or other language extension, the
SIGINT handler is changed, and is restored when GDB leaves extension
language. GDB only stays in extension language for a very short period
in this case, but if ctrl-c is pressed at that moment, python extension
will handle the SIGINT, and exceptions.KeyboardInterrupt is shown.
Language extension is used in GDB side rather than inferior side,
so GDB should only change SIGINT handler for extension language when
the terminal is ours (not inferior's). This is what this patch does.
With this patch applied, I run random-signal.exp in a loop for 18
hours, and no fail is shown.
gdb:
2016-01-08 Yao Qi <yao.qi@linaro.org>
* extension.c: Include target.h.
(set_active_ext_lang): Only call install_gdb_sigint_handler,
check_quit_flag, and set_quit_flag if target_terminal_is_ours
returns false.
(restore_active_ext_lang): Likewise.
* target.c (target_terminal_is_ours): New function.
* target.h (target_terminal_is_ours): Declare.
When testing with "maint set target-non-stop on", a few
threading-related tests expose an issue that requires new RSP packets.
Say there are 3 threads running, 1-3. If GDB tries to stop thread 1,
2 and 3, and then waits for their stops, but meanwhile say, thread 2
exits, GDB hangs forever waiting for a stop for thread 2 that won't
ever happen.
This patch fixes the issue by adding support for thread exit events to
the protocol. However, we don't want these always enabled, as they're
useless most of the time, and would slow down remote debugging. So I
made it so that GDB can enable/disable them, and then made gdb do that
around the cases that need it, which currently is only
infrun.c:stop_all_threads.
In turn, if we have thread exit events, then the extra "thread x
exited" traffic slows down attach-many-short-lived-threads.exp enough
that gdb has trouble keeping up with new threads that are spawned
while gdb tries to stop existing ones. To fix that I added support
for the counterpart thread created events too. Enabling those when we
try to stop threads ensures that new threads never get a chance to
themselves start new threads, killing the race.
gdb/doc/ChangeLog:
2015-11-30 Pedro Alves <palves@redhat.com>
* gdb.texinfo (Remote Configuration): List "set/show remote
thread-events" command in configuration table.
(Stop Reply Packets): Document "T05 create" stop
reason and 'w' stop reply.
(General Query Packets): Document QThreadEvents packet. Document
QThreadEvents qSupported feature.
gdb/gdbserver/ChangeLog:
2015-11-30 Pedro Alves <palves@redhat.com>
* linux-low.c (handle_extended_wait): Assert that the LWP's
waitstatus is TARGET_WAITKIND_IGNORE. If GDB wants to hear about
thread create events, leave the new child's status pending.
(linux_low_filter_event): If GDB wants to hear about thread exit
events, leave the LWP marked dead and don't delete it.
(linux_wait_for_event_filtered): Don't check for thread exit.
(filter_exit_event): New function.
(linux_wait_1): Use it, when returning an exit event.
(linux_resume_one_lwp_throw): Assert that the LWP's
waitstatus is TARGET_WAITKIND_IGNORE.
* remote-utils.c (prepare_resume_reply): Handle
TARGET_WAITKIND_THREAD_CREATED and TARGET_WAITKIND_THREAD_EXITED.
* server.c (report_thread_events): New global.
(handle_general_set): Handle QThreadEvents.
(handle_query) <qSupported>: Handle and report QThreadEvents+;
(handle_target_event): Handle TARGET_WAITKIND_THREAD_CREATED and
TARGET_WAITKIND_THREAD_EXITED.
* server.h (report_thread_events): Declare.
gdb/ChangeLog:
2015-11-30 Pedro Alves <palves@redhat.com>
* NEWS (New commands): Mention "set/show remote thread-events"
commands.
(New remote packets): Mention thread created/exited stop reasons
and QThreadEvents packet.
* infrun.c (disable_thread_events): New function.
(stop_all_threads): Disable/enable thread create/exit events.
Handle TARGET_WAITKIND_THREAD_EXITED.
(handle_inferior_event_1): Handle TARGET_WAITKIND_THREAD_CREATED
and TARGET_WAITKIND_THREAD_EXITED.
* remote.c (remove_child_of_pending_fork): Also remove threads of
threads that have TARGET_WAITKIND_THREAD_EXITED events.
(remote_parse_stop_reply): Handle "create" magic register. Handle
'w' stop reply.
(initialize_remote): Install remote_thread_events as
to_thread_events target hook.
(remote_thread_events): New function.
* target-delegates.c: Regenerate.
* target.c (target_thread_events): New function.
* target.h (struct target_ops) <to_thread_events>: New field.
(target_thread_events): Declare.
* target/waitstatus.c (target_waitstatus_to_string): Handle
TARGET_WAITKIND_THREAD_CREATED and TARGET_WAITKIND_THREAD_EXITED.
* target/waitstatus.h (enum target_waitkind)
<TARGET_WAITKIND_THREAD_CREATED, TARGET_WAITKIND_THREAD_EXITED):
New values.
Since this code path returns a string owned by the target (we don't know how
it's allocated, could be a static read-only string), it's safer if we return
a constant string. If, for some reasons, the caller wishes to modify the
string, it should make itself a copy.
gdb/ChangeLog:
* linux-nat.c (linux_nat_thread_name): Constify return value.
* target.h (struct target_ops) <to_thread_name>: Likewise.
(target_thread_name): Likewise.
* target.c (target_thread_name): Likewise.
* target-delegates.c (debug_thread_name): Regenerate.
* python/py-infthread.c (thpy_get_name): Constify local variables.
* thread.c (print_thread_info): Likewise.
(thread_find_command): Likewise.
This patch fixes a typo in target.c:read_memory_robust, where
it calls read_whatever_is_readable with the function arguments
in the wrong order. Depending on the address being read, it
can cause an xmalloc with a huge size, resulting in an assertion
failure, or just read something other than what was requested.
The problem only arises when GDB is handling an MI
"-data-read-memory-bytes" request and the initial target_read returns
an error status. Note that read_memory_robust is only called from
the MI code.
gdb/ChangeLog:
* gdb/target.c (read_memory_robust): Call
read_whatever_is_readable with arguments in the correct order.
Fixes:
src/gdb/remote.c: In function ‘void remote_unpush_target()’:
src/gdb/remote.c:4610:45: error: invalid conversion from ‘int’ to ‘strata’ [-fpermissive]
pop_all_targets_above (process_stratum - 1);
^
In file included from src/gdb/inferior.h:38:0,
from src/gdb/remote.c:25:
src/gdb/target.h:2299:13: error: initializing argument 1 of ‘void pop_all_targets_above(strata)’ [-fpermissive]
extern void pop_all_targets_above (enum strata above_stratum);
^
I used to carry a patch in the C++ branch that just did:
- pop_all_targets_above (process_stratum - 1);
+ pop_all_targets_above ((enum strata) (process_stratum - 1));
But then thought that maybe adding a routine that does exactly what we
need results in clearer code. This is the result.
gdb/ChangeLog:
2015-11-19 Pedro Alves <palves@redhat.com>
* remote.c (remote_unpush_target): Use
pop_all_targets_at_and_above instead of pop_all_targets_above.
* target.c (unpush_target_and_assert): New function, factored out
from ...
(pop_all_targets_above): ... here.
(pop_all_targets_at_and_above): New function.
* target.h (pop_all_targets_at_and_above): Declare.
Years ago, these functions used to return errno/EIO. Later, through a
series of changes that intended to remove native/remote differences,
they ended up returning a target_xfer_status in disguise.
Unlike target_xfer_partial&co, the point of target_read_memory&co is
to either fully succeed or fail. On error, they always return
TARGET_XFER_E_IO. So there's no real point in casting the return of
target_read_memory to a target_xfer_status to pass it to memory_error.
Instead, it results in clearer code to simply decouple
target_read_memory&co's return from target_xfer_status.
This fixes build errors like this in C++ mode:
../../src/gdb/corefile.c: In function ‘void read_stack(CORE_ADDR, gdb_byte*, ssize_t)’:
../../src/gdb/corefile.c:276:34: error: invalid conversion from ‘int’ to ‘target_xfer_status’ [-fpermissive]
memory_error (status, memaddr);
^
../../src/gdb/corefile.c:216:1: error: initializing argument 1 of ‘void memory_error(target_xfer_status, CORE_ADDR)’ [-fpermissive]
gdb/ChangeLog:
2015-10-27 Pedro Alves <palves@redhat.com>
* alpha-tdep.c (alpha_read_insn): Always pass TARGET_XFER_E_IO to
memory_error. Rename local 'status' to 'res'.
* c-lang.c (c_get_string): Always pass TARGET_XFER_E_IO to
memory_error.
* corefile.c (read_stack, read_code, write_memory): Always pass
TARGET_XFER_E_IO to memory_error.
* disasm.c (dis_asm_memory_error): Always pass TARGET_XFER_E_IO to
memory_error. Rename parameter 'status' to 'err'.
(dump_insns): Rename local 'status' to 'err'.
* mips-tdep.c (mips_fetch_instruction): Rename parameter 'statusp'
to 'errp'. Rename local 'status' to 'err'. Always pass
TARGET_XFER_E_IO to memory_error.
(mips_breakpoint_from_pc): Rename local 'status' to 'err'.
* target.c (target_read_memory, target_read_raw_memory)
(target_read_stack, target_read_code, target_write_memory)
(target_write_raw_memory): Return -1 on error instead of
TARGET_XFER_E_IO.
* valprint.c (val_print_string): Rename local 'errcode' to 'err'.
Always pass TARGET_XFER_E_IO to memory_error. Update comment.
Fixes some errors in C++ build.
gdb/ChangeLog:
* target.c (memory_xfer_partial): Change type of buf to gdb_byte
pointer.
(simple_search_memory): Cast return of memmem.