[05/10] m68k: Implement backtrace on top of <unwind-link.h>
Commit Message
---
sysdeps/m68k/backtrace.c | 82 +++++++++-------------------------------
1 file changed, 18 insertions(+), 64 deletions(-)
Comments
On 2/17/21 11:03 AM, Florian Weimer via Libc-alpha wrote:
LGTM. And the m68k version.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
> ---
> sysdeps/m68k/backtrace.c | 82 +++++++++-------------------------------
> 1 file changed, 18 insertions(+), 64 deletions(-)
>
> diff --git a/sysdeps/m68k/backtrace.c b/sysdeps/m68k/backtrace.c
> index 86e9a888f0..27b9c58167 100644
> --- a/sysdeps/m68k/backtrace.c
> +++ b/sysdeps/m68k/backtrace.c
> @@ -16,52 +16,18 @@
> License along with the GNU C Library; if not, see
> <https://www.gnu.org/licenses/>. */
>
> -#include <libc-lock.h>
> -#include <dlfcn.h>
> #include <execinfo.h>
> #include <stdlib.h>
> -#include <unwind.h>
> +#include <unwind-link.h>
>
> struct trace_arg
> {
> void **array;
> + struct unwind_link *unwind_link;
> int cnt, size;
> void *lastfp, *lastsp;
> };
>
> -#ifdef SHARED
> -static _Unwind_Reason_Code (*unwind_backtrace) (_Unwind_Trace_Fn, void *);
> -static _Unwind_Ptr (*unwind_getip) (struct _Unwind_Context *);
> -static _Unwind_Ptr (*unwind_getcfa) (struct _Unwind_Context *);
> -static _Unwind_Ptr (*unwind_getgr) (struct _Unwind_Context *, int);
> -static void *libgcc_handle;
> -
> -static void
> -init (void)
> -{
> - libgcc_handle = __libc_dlopen ("libgcc_s.so.2");
> -
> - if (libgcc_handle == NULL)
> - return;
> -
> - unwind_backtrace = __libc_dlsym (libgcc_handle, "_Unwind_Backtrace");
> - unwind_getip = __libc_dlsym (libgcc_handle, "_Unwind_GetIP");
> - unwind_getcfa = __libc_dlsym (libgcc_handle, "_Unwind_GetCFA");
> - unwind_getgr = __libc_dlsym (libgcc_handle, "_Unwind_GetGR");
> - if (unwind_getip == NULL || unwind_getgr == NULL || unwind_getcfa == NULL)
> - {
> - unwind_backtrace = NULL;
> - __libc_dlclose (libgcc_handle);
> - libgcc_handle = NULL;
> - }
> -}
> -#else
> -# define unwind_backtrace _Unwind_Backtrace
> -# define unwind_getip _Unwind_GetIP
> -# define unwind_getcfa _Unwind_GetCFA
> -# define unwind_getgr _Unwind_GetGR
> -#endif
> -
> static _Unwind_Reason_Code
> backtrace_helper (struct _Unwind_Context *ctx, void *a)
> {
> @@ -70,13 +36,16 @@ backtrace_helper (struct _Unwind_Context *ctx, void *a)
> /* We are first called with address in the __backtrace function.
> Skip it. */
> if (arg->cnt != -1)
> - arg->array[arg->cnt] = (void *) unwind_getip (ctx);
> + arg->array[arg->cnt]
> + = (void *) UNWIND_LINK_PTR (arg->unwind_link, _Unwind_GetIP) (ctx);
> if (++arg->cnt == arg->size)
> return _URC_END_OF_STACK;
>
> /* %fp is DWARF2 register 14 on M68K. */
> - arg->lastfp = (void *) unwind_getgr (ctx, 14);
> - arg->lastsp = (void *) unwind_getcfa (ctx);
> + arg->lastfp
> + = (void *) UNWIND_LINK_PTR (arg->unwind_link, _Unwind_GetGR) (ctx, 14);
> + arg->lastsp
> + = (void *) UNWIND_LINK_PTR (arg->unwind_link, _Unwind_GetCFA) (ctx);
> return _URC_NO_REASON;
> }
>
> @@ -110,20 +79,19 @@ struct layout
> int
> __backtrace (void **array, int size)
> {
> - struct trace_arg arg = { .array = array, .size = size, .cnt = -1 };
> -
> - if (size <= 0)
> - return 0;
> -
> -#ifdef SHARED
> - __libc_once_define (static, once);
> + struct trace_arg arg =
> + {
> + .array = array,
> + .unwind_link = __libc_unwind_link_get (),
> + .size = size,
> + .cnt = -1,
> + };
>
> - __libc_once (once, init);
> - if (unwind_backtrace == NULL)
> + if (size <= 0 || arg.unwind_link == NULL)
> return 0;
> -#endif
>
> - unwind_backtrace (backtrace_helper, &arg);
> + UNWIND_LINK_PTR (arg.unwind_link, _Unwind_Backtrace)
> + (backtrace_helper, &arg);
>
> if (arg.cnt > 1 && arg.array[arg.cnt - 1] == NULL)
> --arg.cnt;
> @@ -146,17 +114,3 @@ __backtrace (void **array, int size)
> }
> weak_alias (__backtrace, backtrace)
> libc_hidden_def (__backtrace)
> -
> -
> -#ifdef SHARED
> -/* Free all resources if necessary. */
> -libc_freeres_fn (free_mem)
> -{
> - unwind_backtrace = NULL;
> - if (libgcc_handle != NULL)
> - {
> - __libc_dlclose (libgcc_handle);
> - libgcc_handle = NULL;
> - }
> -}
> -#endif
>
@@ -16,52 +16,18 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
-#include <libc-lock.h>
-#include <dlfcn.h>
#include <execinfo.h>
#include <stdlib.h>
-#include <unwind.h>
+#include <unwind-link.h>
struct trace_arg
{
void **array;
+ struct unwind_link *unwind_link;
int cnt, size;
void *lastfp, *lastsp;
};
-#ifdef SHARED
-static _Unwind_Reason_Code (*unwind_backtrace) (_Unwind_Trace_Fn, void *);
-static _Unwind_Ptr (*unwind_getip) (struct _Unwind_Context *);
-static _Unwind_Ptr (*unwind_getcfa) (struct _Unwind_Context *);
-static _Unwind_Ptr (*unwind_getgr) (struct _Unwind_Context *, int);
-static void *libgcc_handle;
-
-static void
-init (void)
-{
- libgcc_handle = __libc_dlopen ("libgcc_s.so.2");
-
- if (libgcc_handle == NULL)
- return;
-
- unwind_backtrace = __libc_dlsym (libgcc_handle, "_Unwind_Backtrace");
- unwind_getip = __libc_dlsym (libgcc_handle, "_Unwind_GetIP");
- unwind_getcfa = __libc_dlsym (libgcc_handle, "_Unwind_GetCFA");
- unwind_getgr = __libc_dlsym (libgcc_handle, "_Unwind_GetGR");
- if (unwind_getip == NULL || unwind_getgr == NULL || unwind_getcfa == NULL)
- {
- unwind_backtrace = NULL;
- __libc_dlclose (libgcc_handle);
- libgcc_handle = NULL;
- }
-}
-#else
-# define unwind_backtrace _Unwind_Backtrace
-# define unwind_getip _Unwind_GetIP
-# define unwind_getcfa _Unwind_GetCFA
-# define unwind_getgr _Unwind_GetGR
-#endif
-
static _Unwind_Reason_Code
backtrace_helper (struct _Unwind_Context *ctx, void *a)
{
@@ -70,13 +36,16 @@ backtrace_helper (struct _Unwind_Context *ctx, void *a)
/* We are first called with address in the __backtrace function.
Skip it. */
if (arg->cnt != -1)
- arg->array[arg->cnt] = (void *) unwind_getip (ctx);
+ arg->array[arg->cnt]
+ = (void *) UNWIND_LINK_PTR (arg->unwind_link, _Unwind_GetIP) (ctx);
if (++arg->cnt == arg->size)
return _URC_END_OF_STACK;
/* %fp is DWARF2 register 14 on M68K. */
- arg->lastfp = (void *) unwind_getgr (ctx, 14);
- arg->lastsp = (void *) unwind_getcfa (ctx);
+ arg->lastfp
+ = (void *) UNWIND_LINK_PTR (arg->unwind_link, _Unwind_GetGR) (ctx, 14);
+ arg->lastsp
+ = (void *) UNWIND_LINK_PTR (arg->unwind_link, _Unwind_GetCFA) (ctx);
return _URC_NO_REASON;
}
@@ -110,20 +79,19 @@ struct layout
int
__backtrace (void **array, int size)
{
- struct trace_arg arg = { .array = array, .size = size, .cnt = -1 };
-
- if (size <= 0)
- return 0;
-
-#ifdef SHARED
- __libc_once_define (static, once);
+ struct trace_arg arg =
+ {
+ .array = array,
+ .unwind_link = __libc_unwind_link_get (),
+ .size = size,
+ .cnt = -1,
+ };
- __libc_once (once, init);
- if (unwind_backtrace == NULL)
+ if (size <= 0 || arg.unwind_link == NULL)
return 0;
-#endif
- unwind_backtrace (backtrace_helper, &arg);
+ UNWIND_LINK_PTR (arg.unwind_link, _Unwind_Backtrace)
+ (backtrace_helper, &arg);
if (arg.cnt > 1 && arg.array[arg.cnt - 1] == NULL)
--arg.cnt;
@@ -146,17 +114,3 @@ __backtrace (void **array, int size)
}
weak_alias (__backtrace, backtrace)
libc_hidden_def (__backtrace)
-
-
-#ifdef SHARED
-/* Free all resources if necessary. */
-libc_freeres_fn (free_mem)
-{
- unwind_backtrace = NULL;
- if (libgcc_handle != NULL)
- {
- __libc_dlclose (libgcc_handle);
- libgcc_handle = NULL;
- }
-}
-#endif