[v2] xtensa: implement NPTL helpers
Commit Message
These changes allow debugging multithreaded NPTL xtensa applications.
2015-08-20 Max Filippov <jcmvbkbc@gmail.com>
gdb/gdbserver/
* configure.srv (xtensa*-*-linux*): Add srv_linux_thread_db=yes.
* linux-xtensa-low.c (xtensa-tdep.h gdb_proc_service.h): New
#includes.
(ps_get_thread_area): New function.
2015-08-20 Max Filippov <jcmvbkbc@gmail.com>
gdb/
* xtensa-linux-nat.c (gdb_proc_service.h): New #include.
(ps_get_thread_area): New function.
* xtensa-linux-tdep.c (xtensa_linux_init_abi): Add call to
set_gdbarch_fetch_tls_load_module_address to enable TLS support.
* xtensa-tdep.c (osabi.h): New #include.
(xtensa_gdbarch_init): Call gdbarch_init_osabi to register
xtensa-specific hooks.
* xtensa-tdep.h (struct xtensa_elf_gregset_t): Add threadptr
member.
---
Changes v1->v2:
- add missing #include "osabi.h" to xtensa-tdep.c
- add ps_get_thread_area to gdbserver/linux-xtensa-low.c
- enable thread_db use in gdbserver/configure.srv
gdb/gdbserver/configure.srv | 1 +
gdb/gdbserver/linux-xtensa-low.c | 18 ++++++++++++++++++
gdb/xtensa-linux-nat.c | 19 +++++++++++++++++++
gdb/xtensa-linux-tdep.c | 4 ++++
gdb/xtensa-tdep.c | 4 ++++
gdb/xtensa-tdep.h | 3 ++-
6 files changed, 48 insertions(+), 1 deletion(-)
Comments
On 08/21/2015 06:15 AM, Max Filippov wrote:
> These changes allow debugging multithreaded NPTL xtensa applications.
>
> 2015-08-20 Max Filippov <jcmvbkbc@gmail.com>
> gdb/gdbserver/
> * configure.srv (xtensa*-*-linux*): Add srv_linux_thread_db=yes.
> * linux-xtensa-low.c (xtensa-tdep.h gdb_proc_service.h): New
> #includes.
> (ps_get_thread_area): New function.
>
> 2015-08-20 Max Filippov <jcmvbkbc@gmail.com>
> gdb/
> * xtensa-linux-nat.c (gdb_proc_service.h): New #include.
> (ps_get_thread_area): New function.
> * xtensa-linux-tdep.c (xtensa_linux_init_abi): Add call to
> set_gdbarch_fetch_tls_load_module_address to enable TLS support.
> * xtensa-tdep.c (osabi.h): New #include.
> (xtensa_gdbarch_init): Call gdbarch_init_osabi to register
> xtensa-specific hooks.
> * xtensa-tdep.h (struct xtensa_elf_gregset_t): Add threadptr
> member.
> ---
> Changes v1->v2:
> - add missing #include "osabi.h" to xtensa-tdep.c
> - add ps_get_thread_area to gdbserver/linux-xtensa-low.c
> - enable thread_db use in gdbserver/configure.srv
Thanks.
>
> gdb/gdbserver/configure.srv | 1 +
> gdb/gdbserver/linux-xtensa-low.c | 18 ++++++++++++++++++
> gdb/xtensa-linux-nat.c | 19 +++++++++++++++++++
> gdb/xtensa-linux-tdep.c | 4 ++++
> gdb/xtensa-tdep.c | 4 ++++
> gdb/xtensa-tdep.h | 3 ++-
> 6 files changed, 48 insertions(+), 1 deletion(-)
>
> diff --git a/gdb/gdbserver/configure.srv b/gdb/gdbserver/configure.srv
> index 0b18d1d..320c26a 100644
> --- a/gdb/gdbserver/configure.srv
> +++ b/gdb/gdbserver/configure.srv
> @@ -352,6 +352,7 @@ case "${target}" in
> xtensa*-*-linux*) srv_regobj=reg-xtensa.o
> srv_tgtobj="$srv_linux_obj linux-xtensa-low.o"
> srv_linux_regsets=yes
> + srv_linux_thread_db=yes
> ;;
> tilegx-*-linux*) srv_regobj=reg-tilegx.o
> srv_regobj="${srv_regobj} reg-tilegx32.o"
> diff --git a/gdb/gdbserver/linux-xtensa-low.c b/gdb/gdbserver/linux-xtensa-low.c
> index 4daccee..a515f97 100644
> --- a/gdb/gdbserver/linux-xtensa-low.c
> +++ b/gdb/gdbserver/linux-xtensa-low.c
> @@ -25,7 +25,9 @@ void init_registers_xtensa (void);
> extern const struct target_desc *tdesc_xtensa;
>
> #include <asm/ptrace.h>
> +#include <xtensa-tdep.h>
Sorry, but gdbserver must not include gdb-specific files.
Maybe move xtensa_elf_gregset_t to a new gdb/arch/xtensa.h
file.
> #include <xtensa-config.h>
> +#include "gdb_proc_service.h"
>
> #include "xtensa-xtregs.c"
>
> @@ -179,6 +181,22 @@ xtensa_breakpoint_at (CORE_ADDR where)
> xtensa_breakpoint, xtensa_breakpoint_len) == 0;
> }
>
> +ps_err_e
> +ps_get_thread_area (const struct ps_prochandle *ph,
> + lwpid_t lwpid, int idx, void **base)
Missed this in v1, but please add an intro comment. As simple
as
/* Called by libthread_db. */
is enough.
> +{
> + xtensa_elf_gregset_t regs;
> + if (ptrace (PTRACE_GETREGS, lwpid, NULL, ®s) != 0)
Missing empty line after declaration.
> + return PS_ERR;
> +
> + /* IDX is the bias from the thread pointer to the beginning of the
> + thread descriptor. It has to be subtracted due to implementation
> + quirks in libthread_db. */
> + *base = (void *) ((char *)regs.threadptr - idx);
> +
Space after the cast. "(char *) regs".
> + return PS_OK;
> +}
> +
> static struct regsets_info xtensa_regsets_info =
> {
> xtensa_regsets, /* regsets */
> diff --git a/gdb/xtensa-linux-nat.c b/gdb/xtensa-linux-nat.c
> index 77ad3e0..3e5ad5c 100644
> --- a/gdb/xtensa-linux-nat.c
> +++ b/gdb/xtensa-linux-nat.c
> @@ -37,6 +37,9 @@
> #include "gregset.h"
> #include "xtensa-tdep.h"
>
> +/* Defines ps_err_e, struct ps_prochandle. */
> +#include "gdb_proc_service.h"
> +
> /* Extended register set depends on hardware configs.
> Keeping these definitions separately allows to introduce
> hardware-specific overlays. */
> @@ -280,6 +283,22 @@ xtensa_linux_store_inferior_registers (struct target_ops *ops,
> store_xtregs (regcache, regnum);
> }
>
> +ps_err_e
> +ps_get_thread_area (const struct ps_prochandle *ph,
> + lwpid_t lwpid, int idx, void **base)
Intro comment here too.
> +{
> + xtensa_elf_gregset_t regs;
> + if (ptrace (PTRACE_GETREGS, lwpid, NULL, ®s) != 0)
> + return PS_ERR;
> +
> + /* IDX is the bias from the thread pointer to the beginning of the
> + thread descriptor. It has to be subtracted due to implementation
> + quirks in libthread_db. */
> + *base = (void *) ((char *)regs.threadptr - idx);
Missing space.
> +
> + return PS_OK;
> +}
> +
> void _initialize_xtensa_linux_nat (void);
Thanks,
Pedro Alves
@@ -352,6 +352,7 @@ case "${target}" in
xtensa*-*-linux*) srv_regobj=reg-xtensa.o
srv_tgtobj="$srv_linux_obj linux-xtensa-low.o"
srv_linux_regsets=yes
+ srv_linux_thread_db=yes
;;
tilegx-*-linux*) srv_regobj=reg-tilegx.o
srv_regobj="${srv_regobj} reg-tilegx32.o"
@@ -25,7 +25,9 @@ void init_registers_xtensa (void);
extern const struct target_desc *tdesc_xtensa;
#include <asm/ptrace.h>
+#include <xtensa-tdep.h>
#include <xtensa-config.h>
+#include "gdb_proc_service.h"
#include "xtensa-xtregs.c"
@@ -179,6 +181,22 @@ xtensa_breakpoint_at (CORE_ADDR where)
xtensa_breakpoint, xtensa_breakpoint_len) == 0;
}
+ps_err_e
+ps_get_thread_area (const struct ps_prochandle *ph,
+ lwpid_t lwpid, int idx, void **base)
+{
+ xtensa_elf_gregset_t regs;
+ if (ptrace (PTRACE_GETREGS, lwpid, NULL, ®s) != 0)
+ return PS_ERR;
+
+ /* IDX is the bias from the thread pointer to the beginning of the
+ thread descriptor. It has to be subtracted due to implementation
+ quirks in libthread_db. */
+ *base = (void *) ((char *)regs.threadptr - idx);
+
+ return PS_OK;
+}
+
static struct regsets_info xtensa_regsets_info =
{
xtensa_regsets, /* regsets */
@@ -37,6 +37,9 @@
#include "gregset.h"
#include "xtensa-tdep.h"
+/* Defines ps_err_e, struct ps_prochandle. */
+#include "gdb_proc_service.h"
+
/* Extended register set depends on hardware configs.
Keeping these definitions separately allows to introduce
hardware-specific overlays. */
@@ -280,6 +283,22 @@ xtensa_linux_store_inferior_registers (struct target_ops *ops,
store_xtregs (regcache, regnum);
}
+ps_err_e
+ps_get_thread_area (const struct ps_prochandle *ph,
+ lwpid_t lwpid, int idx, void **base)
+{
+ xtensa_elf_gregset_t regs;
+ if (ptrace (PTRACE_GETREGS, lwpid, NULL, ®s) != 0)
+ return PS_ERR;
+
+ /* IDX is the bias from the thread pointer to the beginning of the
+ thread descriptor. It has to be subtracted due to implementation
+ quirks in libthread_db. */
+ *base = (void *) ((char *)regs.threadptr - idx);
+
+ return PS_OK;
+}
+
void _initialize_xtensa_linux_nat (void);
void
@@ -106,6 +106,10 @@ xtensa_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
xtensa_linux_gdb_signal_from_target);
set_gdbarch_gdb_signal_to_target (gdbarch,
xtensa_linux_gdb_signal_to_target);
+
+ /* Enable TLS support. */
+ set_gdbarch_fetch_tls_load_module_address (gdbarch,
+ svr4_fetch_objfile_link_map);
}
/* Provide a prototype to silence -Wmissing-prototypes. */
@@ -28,6 +28,7 @@
#include "value.h"
#include "dis-asm.h"
#include "inferior.h"
+#include "osabi.h"
#include "floatformat.h"
#include "regcache.h"
#include "reggroups.h"
@@ -3273,6 +3274,9 @@ xtensa_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
set_solib_svr4_fetch_link_map_offsets
(gdbarch, svr4_ilp32_fetch_link_map_offsets);
+ /* Hook in the ABI-specific overrides, if they have been registered. */
+ gdbarch_init_osabi (info, gdbarch);
+
return gdbarch;
}
@@ -96,7 +96,8 @@ typedef struct
xtensa_elf_greg_t sar;
xtensa_elf_greg_t windowstart;
xtensa_elf_greg_t windowbase;
- xtensa_elf_greg_t reserved[8+48];
+ xtensa_elf_greg_t threadptr;
+ xtensa_elf_greg_t reserved[7+48];
xtensa_elf_greg_t ar[64];
} xtensa_elf_gregset_t;