The current implementation is forgetting to populate the thread list
when attaching to the process. This results in an incomplete list of
threads when debugging a threaded program.
Unfortunately, as the added comments hints, there appears to be
no way of getting the list of threads via ptrace, other than by
spawning the "ps" command, and parsing its output. Not great,
but it appears to be the best we can do.
gdb/gdbserver/ChangeLog:
* lynx-low.c (lynx_add_threads_after_attach): New function.
(lynx_attach): Remove call to add_thread. Add call to
lynx_add_threads_after_attach instead.
This patch makes GDBserver support multi-process + biarch.
Currently, if you're debugging more than one process at once with a
single gdbserver (in extended-remote mode), then all processes must
have the same architecture (e.g., 64-bit vs 32-bit). Otherwise, you
see this:
Added inferior 2
[Switching to inferior 2 [<null>] (<noexec>)]
Reading symbols from /home/pedro/gdb/tests/main32...done.
Temporary breakpoint 2 at 0x4004cf: main. (2 locations)
Starting program: /home/pedro/gdb/tests/main32
warning: Selected architecture i386 is not compatible with reported target architecture i386:x86-64
warning: Architecture rejected target-supplied description
Remote 'g' packet reply is too long: 000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000090cfffff0000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000000000000000b042f7460000000000020000230000002b0000002b0000002b000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000007f03000000000000ffff0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000801f00003b0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
... etc, etc ...
Even though the process was running a 32-bit program, GDBserver sent
back to GDB a register set in 64-bit layout.
A patch (http://sourceware.org/ml/gdb-patches/2012-11/msg00228.html) a
while ago made GDB track a target_gdbarch per inferior, and as
consequence, fetch a target description per-inferior. This patch is
the GDBserver counterpart, that makes GDBserver keep track of each
process'es XML target description and register layout. So in the
example above, GDBserver will send the correct register set in 32-bit
layout to GDB.
A new "struct target_desc" object (tdesc for short) is added, that
holds the target description and register layout information about
each process. Each `struct process_info' holds a pointer to a target
description. The regcache also gains a pointer to a target
description, mainly for convenience, and parallel with GDB (and
possible future support for programs that flip processor modes).
The low target's arch_setup routines are responsible for setting the
process'es correct tdesc. This isn't that much different to how
things were done before, except that instead of detecting the inferior
process'es architecture and calling the corresponding
init_registers_FOO routine, which would change the regcache layout
globals and recreate the threads' regcaches, the regcache.c globals
are gone, and the init_registers_$BAR routines now each initialize a
separate global struct target_desc object (one for each arch variant
GDBserver supports), and so all the init_registers_$BAR routines that
are built into GDBserver are called early at GDBserver startup time
(similarly to how GDB handles its built-in target descriptions), and
then the arch_setup routine is responsible for making
process_info->tdesc point to one of these target description globals.
The regcache module is all parameterized to get the regcache's layout
from the tdesc object instead of the old register_bytes, etc. globals.
The threads' regcaches are now created lazily. The old scheme where
we created each of them when we added a new thread doesn't work
anymore, because we add the main thread/lwp before we see it stop for
the first time, and it is only when we see the thread stop for the
first time that we have a chance of determining the inferior's
architecture (through the_low_target.arch_setup). Therefore when we
add the main thread we don't know which architecture/tdesc its
regcache should have.
This patch makes the gdb.multi/multi-arch.exp test now pass against
(extended-remote) GDBserver. It currently fails, without this patch.
The IPA also uses the regcache, so it gains a new global struct
target_desc pointer, which points at the description of the process it
is loaded in.
Re. the linux-low.c & friends changes. Since the register map
etc. may differ between processes (64-bit vs 32-bit) etc., the
linux_target_ops num_regs, regmap and regset_bitmap data fields are no
longer sufficient. A new method is added in their place that returns
a pointer to a new struct that includes all info linux-low.c needs to
access registers of the current inferior.
The patch/discussion that originally introduced
linux-low.c:disabled_regsets mentions that the disabled_regsets set
may be different per mode (in a biarch setup), and indeed that is
cleared whenever we start a new (first) inferior, so that global is
moved as well behind the new `struct regs_info'.
On the x86 side:
I simply replaced the i387-fp.c:num_xmm_registers global with a check
for 64-bit or 32-bit process, which is equivalent to how the global
was set. This avoided coming up with some more general mechanism that
would work for all targets that use this module (GNU/Linux, Windows,
etc.).
Tested:
GNU/Linux IA64
GNU/Linux MIPS64
GNU/Linux PowerPC (Fedora 16)
GNU/Linux s390x (Fedora 16)
GNU/Linux sparc64 (Debian)
GNU/Linux x86_64, -m64 and -m32 (Fedora 17)
Cross built, and smoke tested:
i686-w64-mingw32, under Wine.
GNU/Linux TI C6x, by Yao Qi.
Cross built but otherwise not tested:
aarch64-linux-gnu
arm-linux-gnu
m68k-linux
nios2-linux-gnu
sh-linux-gnu
spu
tilegx-unknown-linux-gnu
Completely untested:
GNU/Linux Blackfin
GNU/Linux CRIS
GNU/Linux CRISv32
GNU/Linux TI Xtensa
GNU/Linux M32R
LynxOS
QNX NTO
gdb/gdbserver/
2013-06-07 Pedro Alves <palves@redhat.com>
* Makefile.in (OBS): Add tdesc.o.
(IPA_OBJS): Add tdesc-ipa.o.
(tdesc-ipa.o): New rule.
* ax.c (gdb_eval_agent_expr): Adjust register_size call to new
interface.
* linux-low.c (new_inferior): Delete.
(disabled_regsets, num_regsets): Delete.
(linux_add_process): Adjust to set the new per-process
new_inferior flag.
(linux_detach_one_lwp): Adjust to call regcache_invalidate_thread.
(linux_wait_for_lwp): Adjust. Only call arch_setup if the event
was a stop. When calling arch_setup, switch the current inferior
to the thread that got an event.
(linux_resume_one_lwp): Adjust to call regcache_invalidate_thread.
(regsets_fetch_inferior_registers)
(regsets_store_inferior_registers): New regsets_info parameter.
Adjust to use it.
(linux_register_in_regsets): New regs_info parameter. Adjust to
use it.
(register_addr, fetch_register, store_register): New usrregs_info
parameter. Adjust to use it.
(usr_fetch_inferior_registers, usr_store_inferior_registers): New
parameter regs_info. Adjust to use it.
(linux_fetch_registers): Get the current inferior's regs_info, and
adjust to use it.
(linux_store_registers): Ditto.
[HAVE_LINUX_REGSETS] (initialize_regsets_info): New.
(initialize_low): Don't initialize the target_regsets here. Call
initialize_low_arch.
* linux-low.h (target_regsets): Delete declaration.
(struct regsets_info): New.
(struct usrregs_info): New.
(struct regs_info): New.
(struct process_info_private) <new_inferior>: New field.
(struct linux_target_ops): Delete the num_regs, regmap, and
regset_bitmap fields. New field regs_info.
[HAVE_LINUX_REGSETS] (initialize_regsets_info): Declare.
* i387-fp.c (num_xmm_registers): Delete.
(i387_cache_to_fsave, i387_fsave_to_cache): Adjust find_regno
calls to new interface.
(i387_cache_to_fxsave, i387_cache_to_xsave, i387_fxsave_to_cache)
(i387_xsave_to_cache): Adjust find_regno calls to new interface.
Infer the number of xmm registers from the regcache's target
description.
* i387-fp.h (num_xmm_registers): Delete.
* inferiors.c (add_thread): Don't install the thread's regcache
here.
* proc-service.c (gregset_info): Fetch the current inferior's
regs_info. Adjust to use it.
* regcache.c: Include tdesc.h.
(register_bytes, reg_defs, num_registers)
(gdbserver_expedite_regs): Delete.
(get_thread_regcache): If the thread doesn't have a regcache yet,
create one, instead of aborting gdbserver.
(regcache_invalidate_one): Rename to ...
(regcache_invalidate_thread): ... this.
(regcache_invalidate_one): New.
(regcache_invalidate): Only invalidate registers of the current
process.
(init_register_cache): Add target_desc parameter, and use it.
(new_register_cache): Ditto. Assert the target description has a
non zero registers_size.
(regcache_cpy): Add assertions. Adjust.
(realloc_register_cache, set_register_cache): Delete.
(registers_to_string, registers_from_string): Adjust.
(find_register_by_name, find_regno, find_register_by_number)
(register_cache_size): Add target_desc parameter, and use it.
(free_register_cache_thread, free_register_cache_thread_one)
(regcache_release, register_cache_size): New.
(register_size): Add target_desc parameter, and use it.
(register_data, supply_register, supply_register_zeroed)
(supply_regblock, supply_register_by_name, collect_register)
(collect_register_as_string, collect_register_by_name): Adjust.
* regcache.h (struct target_desc): Forward declare.
(struct regcache) <tdesc>: New field.
(init_register_cache, new_register_cache): Add target_desc
parameter.
(regcache_invalidate_thread): Declare.
(regcache_invalidate_one): Delete declaration.
(regcache_release): Declare.
(find_register_by_number, register_cache_size, register_size)
(find_regno): Add target_desc parameter.
(gdbserver_expedite_regs, gdbserver_xmltarget): Delete
declarations.
* remote-utils.c: Include tdesc.h.
(outreg, prepare_resume_reply): Adjust.
* server.c: Include tdesc.h.
(gdbserver_xmltarget): Delete declaration.
(get_features_xml, process_serial_event): Adjust.
* server.h [IN_PROCESS_AGENT] (struct target_desc): Forward
declare.
(struct process_info) <tdesc>: New field.
(ipa_tdesc): Declare.
* tdesc.c: New file.
* tdesc.h: New file.
* tracepoint.c: Include tdesc.h.
[IN_PROCESS_AGENT] (ipa_tdesc): Define.
(get_context_regcache): Adjust to pass ipa_tdesc down.
(do_action_at_tracepoint): Adjust to get the register cache size
from the context regcache's description.
(traceframe_walk_blocks): Adjust to get the register cache size
from the current trace frame's description.
(traceframe_get_pc): Adjust to get current trace frame's
description and pass it down.
(gdb_collect): Adjust to get the register cache size from the
IPA's description.
* linux-amd64-ipa.c (tdesc_amd64_linux): Declare.
(gdbserver_xmltarget): Delete.
(initialize_low_tracepoint): Set the ipa's target description.
* linux-i386-ipa.c (tdesc_i386_linux): Declare.
(initialize_low_tracepoint): Set the ipa's target description.
* linux-x86-low.c: Include tdesc.h.
[__x86_64__] (is_64bit_tdesc): New.
(ps_get_thread_area, x86_get_thread_area): Use it.
(i386_cannot_store_register): Rename to ...
(x86_cannot_store_register): ... this. Use is_64bit_tdesc.
(i386_cannot_fetch_register): Rename to ...
(x86_cannot_fetch_register): ... this. Use is_64bit_tdesc.
(x86_fill_gregset, x86_store_gregset): Adjust register_size calls
to new interface.
(target_regsets): Rename to ...
(x86_regsets): ... this.
(x86_get_pc, x86_set_pc): Adjust register_size calls to new
interface.
(x86_siginfo_fixup): Use is_64bit_tdesc.
[__x86_64__] (tdesc_amd64_linux, tdesc_amd64_avx_linux)
(tdesc_x32_avx_linux, tdesc_x32_linux)
(tdesc_i386_linux, tdesc_i386_mmx_linux, tdesc_i386_avx_linux):
Declare.
(x86_linux_update_xmltarget): Delete.
(I386_LINUX_XSAVE_XCR0_OFFSET): Define.
(have_ptrace_getfpxregs, have_ptrace_getregset): New.
(AMD64_LINUX_USER64_CS): New.
(x86_linux_read_description): New, based on
x86_linux_update_xmltarget.
(same_process_callback): New.
(x86_arch_setup_process_callback): New.
(x86_linux_update_xmltarget): New.
(x86_regsets_info): New.
(amd64_linux_regs_info): New.
(i386_linux_usrregs_info): New.
(i386_linux_regs_info): New.
(x86_linux_regs_info): New.
(x86_arch_setup): Reimplement.
(x86_install_fast_tracepoint_jump_pad): Use is_64bit_tdesc.
(x86_emit_ops): Ditto.
(the_low_target): Adjust. Install x86_linux_regs_info,
x86_cannot_fetch_register, and x86_cannot_store_register.
(initialize_low_arch): New.
* linux-ia64-low.c (tdesc_ia64): Declare.
(ia64_fetch_register): Adjust.
(ia64_usrregs_info, regs_info): New globals.
(ia64_regs_info): New function.
(the_low_target): Adjust.
(initialize_low_arch): New function.
* linux-sparc-low.c (tdesc_sparc64): Declare.
(sparc_fill_gregset_to_stack, sparc_store_gregset_from_stack):
Adjust.
(sparc_arch_setup): New function.
(sparc_regsets_info, sparc_usrregs_info, regs_info): New globals.
(the_low_target): Adjust.
(initialize_low_arch): New function.
* linux-ppc-low.c (tdesc_powerpc_32l, tdesc_powerpc_altivec32l)
(tdesc_powerpc_cell32l, tdesc_powerpc_vsx32l)
(tdesc_powerpc_isa205_32l, tdesc_powerpc_isa205_altivec32l)
(tdesc_powerpc_isa205_vsx32l, tdesc_powerpc_e500l)
(tdesc_powerpc_64l, tdesc_powerpc_altivec64l)
(tdesc_powerpc_cell64l, tdesc_powerpc_vsx64l)
(tdesc_powerpc_isa205_64l, tdesc_powerpc_isa205_altivec64l)
(tdesc_powerpc_isa205_vsx64l): Declare.
(ppc_cannot_store_register, ppc_collect_ptrace_register)
(ppc_supply_ptrace_register, parse_spufs_run, ppc_get_pc)
(ppc_set_pc, ppc_get_hwcap): Adjust.
(ppc_usrregs_info): Forward declare.
(!__powerpc64__) ppc_regmap_adjusted: New global.
(ppc_arch_setup): Adjust to the current process'es target
description.
(ppc_fill_vsxregset, ppc_store_vsxregset, ppc_fill_vrregset)
(ppc_store_vrregset, ppc_fill_evrregset, ppc_store_evrregse)
(ppc_store_evrregset): Adjust.
(target_regsets): Rename to ...
(ppc_regsets): ... this, and make static.
(ppc_usrregs_info, ppc_regsets_info, regs_info): New globals.
(ppc_regs_info): New function.
(the_low_target): Adjust.
(initialize_low_arch): New function.
* linux-s390-low.c (tdesc_s390_linux32, tdesc_s390_linux32v1)
(tdesc_s390_linux32v2, tdesc_s390_linux64, tdesc_s390_linux64v1)
(tdesc_s390_linux64v2, tdesc_s390x_linux64, tdesc_s390x_linux64v1)
(tdesc_s390x_linux64v2): Declare.
(s390_collect_ptrace_register, s390_supply_ptrace_register)
(s390_fill_gregset, s390_store_last_break): Adjust.
(target_regsets): Rename to ...
(s390_regsets): ... this, and make static.
(s390_get_pc, s390_set_pc): Adjust.
(s390_get_hwcap): New target_desc parameter, and use it.
[__s390x__] (have_hwcap_s390_high_gprs): New global.
(s390_arch_setup): Adjust to set the current process'es target
description. Don't adjust the regmap.
(s390_usrregs_info, s390_regsets_info, regs_info): New globals.
[__s390x__] (s390_usrregs_info_3264, s390_regsets_info_3264)
(regs_info_3264): New globals.
(s390_regs_info): New function.
(the_low_target): Adjust.
(initialize_low_arch): New function.
* linux-mips-low.c (tdesc_mips_linux, tdesc_mips_dsp_linux)
(tdesc_mips64_linux, tdesc_mips64_dsp_linux): Declare.
[__mips64] (init_registers_mips_linux)
(init_registers_mips_dsp_linux): Delete defines.
[__mips64] (tdesc_mips_linux, tdesc_mips_dsp_linux): New defines.
(have_dsp): New global.
(mips_read_description): New, based on mips_arch_setup.
(mips_arch_setup): Reimplement.
(get_usrregs_info): New function.
(mips_cannot_fetch_register, mips_cannot_store_register)
(mips_get_pc, mips_set_pc, mips_fill_gregset, mips_store_gregset)
(mips_fill_fpregset, mips_store_fpregset): Adjust.
(target_regsets): Rename to ...
(mips_regsets): ... this, and make static.
(mips_regsets_info, mips_dsp_usrregs_info, mips_usrregs_info)
(dsp_regs_info, regs_info): New globals.
(mips_regs_info): New function.
(the_low_target): Adjust.
(initialize_low_arch): New function.
* linux-arm-low.c (tdesc_arm, tdesc_arm_with_iwmmxt)
(tdesc_arm_with_vfpv2, tdesc_arm_with_vfpv3, tdesc_arm_with_neon):
Declare.
(arm_fill_vfpregset, arm_store_vfpregset): Adjust.
(arm_read_description): New, with bits factored from
arm_arch_setup.
(arm_arch_setup): Reimplement.
(target_regsets): Rename to ...
(arm_regsets): ... this, and make static.
(arm_regsets_info, arm_usrregs_info, regs_info): New globals.
(arm_regs_info): New function.
(the_low_target): Adjust.
(initialize_low_arch): New function.
* linux-m68k-low.c (tdesc_m68k): Declare.
(target_regsets): Rename to ...
(m68k_regsets): ... this, and make static.
(m68k_regsets_info, m68k_usrregs_info, regs_info): New globals.
(m68k_regs_info): New function.
(m68k_arch_setup): New function.
(the_low_target): Adjust.
(initialize_low_arch): New function.
* linux-sh-low.c (tdesc_sharch): Declare.
(target_regsets): Rename to ...
(sh_regsets): ... this, and make static.
(sh_regsets_info, sh_usrregs_info, regs_info): New globals.
(sh_regs_info, sh_arch_setup): New functions.
(the_low_target): Adjust.
(initialize_low_arch): New function.
* linux-bfin-low.c (tdesc_bfin): Declare.
(bfin_arch_setup): New function.
(bfin_usrregs_info, regs_info): New globals.
(bfin_regs_info): New function.
(the_low_target): Adjust.
(initialize_low_arch): New function.
* linux-cris-low.c (tdesc_cris): Declare.
(cris_arch_setup): New function.
(cris_usrregs_info, regs_info): New globals.
(cris_regs_info): New function.
(the_low_target): Adjust.
(initialize_low_arch): New function.
* linux-cris-low.c (tdesc_crisv32): Declare.
(cris_arch_setup): New function.
(cris_regsets_info, cris_usrregs_info, regs_info): New globals.
(cris_regs_info): New function.
(the_low_target): Adjust.
(initialize_low_arch): New function.
* linux-m32r-low.c (tdesc_m32r): Declare.
(m32r_arch_setup): New function.
(m32r_usrregs_info, regs_info): New globals.
(m32r_regs_info): Adjust.
(initialize_low_arch): New function.
* linux-tic6x-low.c (tdesc_tic6x_c64xp_linux)
(tdesc_tic6x_c64x_linux, tdesc_tic6x_c62x_linux): Declare.
(tic6x_usrregs_info): Forward declare.
(tic6x_read_description): New function, based on ...
(tic6x_arch_setup): ... this. Reimplement.
(target_regsets): Rename to ...
(tic6x_regsets): ... this, and make static.
(tic6x_regsets_info, tic6x_usrregs_info, regs_info): New globals.
(tic6x_regs_info): New function.
(the_low_target): Adjust.
(initialize_low_arch): New function.
* linux-xtensa-low.c (tdesc_xtensa): Declare.
(xtensa_fill_gregset, xtensa_store_gregset): Adjust.
(target_regsets): Rename to ...
(xtensa_regsets): ... this, and make static.
(xtensa_regsets_info, xtensa_usrregs_info, regs_info): New
globals.
(xtensa_arch_setup, xtensa_regs_info): New functions.
(the_low_target): Adjust.
(initialize_low_arch): New function.
* linux-nios2-low.c (tdesc_nios2_linux): Declare.
(nios2_arch_setup): Set the current process'es tdesc.
(target_regsets): Rename to ...
(nios2_regsets): ... this.
(nios2_regsets_info, nios2_usrregs_info, regs_info): New globals.
(nios2_regs_info): New function.
(the_low_target): Adjust.
(initialize_low_arch): New function.
* linux-aarch64-low.c (tdesc_aarch64): Declare.
(aarch64_arch_setup): Set the current process'es tdesc.
(target_regsets): Rename to ...
(aarch64_regsets): ... this.
(aarch64_regsets_info, aarch64_usrregs_info, regs_info): New globals.
(aarch64_regs_info): New function.
(the_low_target): Adjust.
(initialize_low_arch): New function.
* linux-tile-low.c (tdesc_tilegx, tdesc_tilegx32): Declare
globals.
(target_regsets): Rename to ...
(tile_regsets): ... this.
(tile_regsets_info, tile_usrregs_info, regs_info): New globals.
(tile_regs_info): New function.
(tile_arch_setup): Set the current process'es tdesc.
(the_low_target): Adjust.
(initialize_low_arch): New function.
* spu-low.c (tdesc_spu): Declare.
(spu_create_inferior, spu_attach): Set the new process'es tdesc.
* win32-arm-low.c (tdesc_arm): Declare.
(arm_arch_setup): New function.
(the_low_target): Install arm_arch_setup instead of
init_registers_arm.
* win32-i386-low.c (tdesc_i386, tdesc_amd64): Declare.
(init_windows_x86): Rename to ...
(i386_arch_setup): ... this. Set `win32_tdesc'.
(the_low_target): Adjust.
* win32-low.c (win32_tdesc): New global.
(child_add_thread): Don't create the thread cache here.
(do_initial_child_stuff): Set the new process'es tdesc.
* win32-low.h (struct target_desc): Forward declare.
(win32_tdesc): Declare.
* lynx-i386-low.c (tdesc_i386): Declare global.
(lynx_i386_arch_setup): Set `lynx_tdesc'.
* lynx-low.c (lynx_tdesc): New global.
(lynx_add_process): Set the new process'es tdesc.
* lynx-low.h (struct target_desc): Forward declare.
(lynx_tdesc): Declare global.
* lynx-ppc-low.c (tdesc_powerpc_32): Declare global.
(lynx_ppc_arch_setup): Set `lynx_tdesc'.
* nto-low.c (nto_tdesc): New global.
(do_attach): Set the new process'es tdesc.
* nto-low.h (struct target_desc): Forward declare.
(nto_tdesc): Declare.
* nto-x86-low.c (tdesc_i386): Declare.
(nto_x86_arch_setup): Set `nto_tdesc'.
gdb/
2013-06-07 Pedro Alves <palves@redhat.com>
* regformats/regdat.sh: Output #include tdesc.h. Make globals
static. Output a global target description pointer.
(init_registers_${name}): Adjust to initialize a
target description structure.
On ppc-lynx178, resuming the execution of a program after hitting
a breakpoint sometimes triggers a spurious SIG61 event:
(gdb) cont
Continuing.
Program received signal SIG61, Real-time event 61.
[Switching to Thread 39]
0x10002324 in a_test.task1 (<_task>=0x3ffff774) at a_test.adb:30
30 select -- Task 1
From this point on, continuing again lets the signal kill the program.
Using "signal 0" or configuring GDB to discard the signal does not
help either, as the program immediately reports the same signal again.
What happens is the following:
- GDB sends a single-step order to gdbserver: $vCont;s:31
This tells GDBserver to do a step using thread 0x31=49.
GDBserver does the step, and thread 49 receives the SIGTRAP
indicating that the step has finished.
- GDB then sends a "continue", but this time does not specify
which thread to continue: $vCont;c
GDBserver uses an arbitrary thread's ptid to resume the program's
execution (the current_inferior's ptid was chosen for that).
See lynx-low.c:lynx_resume:
if (ptid_equal (ptid, minus_one_ptid))
ptid = thread_to_gdb_id (current_inferior);
So far on all LynxOS platforms, this has been good enough. But
not so on LynxOS 178. If the ptid used to resume the execution
is not the same as the thread that did the step, we get the weird
signal.
This patch fixes the problem by saving the ptid of the thread
that last caused an event, received during a call to waitpid.
The ptid is saved in per-process private data.
gdb/gdbserver/ChangeLog:
* lynx-low.c (struct process_info_private): New type.
(lynx_add_process): New function.
(lynx_create_inferior, lynx_attach): Replace calls to
add_process by calls to lynx_add_process.
(lynx_resume): If PTID is null, then try using
current_process()->private->last_wait_event_ptid.
Add comments.
(lynx_clear_inferiors): Delete. The contents of that function
has been inlined in lynx_mourn;
(lynx_wait_1): Save the ptid in the process's private data.
(lynx_mourn): Free the process' private data. Replace call
to lynx_clear_inferiors by call to clear_inferiors.
... following Pedro's advice of using a temporary macro.
gdb/gdbserver/ChangeLog:
* lynx-low.c (ptrace_request_to_str): Define a temporary
macro and use it to simplify this function's implementation.
Before this patch, the ptid passed to lynx_resume was completely
ignored, and we used the current_inferior. This resulted in trying
to resume the inferior execution using the wrong ptid after having
received a thread create/exit event, because the inferior_ptid
was still set to the ptid prior to receiving the signal.
gdb/gdbserver/ChangeLog:
* lynx-low.c (lynx_resume): Use the resume_info parameter
to determine the ptid for the lynx_ptrace call, unless
it is equal to minus_one_ptid, in which case we use the
ptid of the current_inferior.
(lynx_wait_1): After having received a thread create/exit
event, resume the inferior's execution using the signaling
thread's ptid, rather than the old ptid.
Two modifications:
1. The addition of 2013 to the copyright year range for every file;
2. The use of a single year range, instead of potentially multiple
year ranges, as approved by the FSF.
We use this ptrace request when handling SIGTRAP signals,
and without this change, the debug trances show:
PTRACE (<unknown-request>, ...
This patch fixes this.
gdb/gdbserver/ChangeLog:
* lynx-low.c (ptrace_request_to_str): Add handling for
PTRACE_GETTRACESIG.
LynxOS 178 does not define this macro.
gdb/gdbserver/ChangeLog:
* lynx-low.c (ptrace_request_to_str): Do not handle
PTRACE_GETTHREADLIST if this macro does not exist.
ARI fixes: move gdb_wait and gdb_stat headers to common subdirectory.
* gdb_stat.h: Delete. Moved to common directory.
* common/gdb_stat.h: New file.
* gdb_wait.h: Delete. Moved to common directory.
* common/gdb_wait.h: New file.
* Makefile.in (H_FILES_NO_SRC): Adapt to new header
location.
* contrib/ari/gdb_ari.sh (wait.h rule): Adapt to new gdb_wait.h
location.
(stat.h rule): Adapt to new gdb_stat.h location.
* common/linux-osdata.c: Include "gdb_stat.h" header instead of
<sys/stat.h> header.
* common/linux-ptrace.c: Include "gdb_wait.h" header instead of
<sys/wait.h> header.
gdbserver ChangeLog entry:
2012-11-15 Pierre Muller <muller@sourceware.org>
* configure.ac (AC_CHECK_HEADERS): Add wait.h header.
* config.in: Regenerate.
* configure: Regenerate.
* linux-low.c: Use "gdb_stat.h" header instead of <sys/stat.h> header.
Use "gdb_wait.h" header instead of <sys/wait.h> header.
* lynx-low.c: Use "gdb_wait.h" header instead of <sys/wait.h> header.
* remote-utils.c: Use "gdb_stat.h" header instead of <sys/stat.h>
header.
* server.c: Remove HAVE_WAIT_H conditional. Use "gdb_wait.h" header
instead of <sys/wait.h> header.
* spu-low.c: Use "gdb_wait.h" header instead of <sys/wait.h> header.
Some of the PTRACE_ macros/values were removed in LynxOS 5.x.
Since we have not use them so far, the chances that we will use them
one day are very small. So I decided to delete them.
gdb/gdbserver/ChangeLog:
* lynx-low.c (ptrace_request_to_str): Remove handling for
request values that have been removed in LynxOS 5.x.
This is one of the changes needed in order to build gdbserver on
LynxOS 5.x.
Really interesting: On LynxOS 4.x, there is a #warning when sys/ptrace.h
is used (explaining that ptrace.h will be used instead), whereas this
file was removed from LynxOS 5.x. The contents of sys/ptrace.h on 4.x
(or at least the meat of it):
#if defined(__GNUC__) || defined(__GNUG__)
#if !defined(__NO_INCLUDE_WARN__)
#warning Using <ptrace.h> instead of <sys/ptrace.h>
#endif /* defined(__NO_INCLUDE_WARN__) */
#endif /* defined(__GNUC__) || defined(__GNUG__) */
#include <ptrace.h>
The fix I went for, for now, is to just include <sys/ptrace.h>
unconditionally. I could have done some configury, but we already
have to build with -D__NO_INCLUDE_WARN__ to avoid the warnings
anyway, and that's unvoidable, due to system includes themselves
including the "wrong" header file.
Since <sys/ptrace.h> seems to be the choice that was made for LynxOS,
and since it works to include it on LynxOS 4.x, I think that's the simplest
solution.
gdb/gdbserver/ChangeLog:
* lynx-low.c, lynx-ppc-low.c: Include <sys/ptrace.h> instead of
<ptrace.h>
This patch adds support for powerpc-lynxos.
gdbserver/ChangeLog:
* gdbserver/lynx-low.c, gdbserver/lynx-low.h,
gdbserver/lynx-ppc-low.c: New files.
* Makefile.in (lynx_low_h): New variable.
(lynx-low.o, lynx-ppc-low.o): New rules.
* configure.ac: On LynxOS, link with -lnetinet.
* configure.srv: Add handling of powerpc-*-lynxos* targets.
* configure: regenerate.
