Message ID | 00a31f83fdc74473ba1eaac8fa49d1f46a2d706c.1581613260.git.fweimer@redhat.com |
---|---|
State | New |
Headers | show |
Series | Unify dynamic loading of the libgcc_s unwinder | expand |
Hi Florian, I've applied your patch series and also successfully run the testsuite on s390x/s390. For s390, this is okay. Just as info for future readers regarding "The S/390 version preserves the backchain fallback for now.": Here is the previous discussion: https://www.sourceware.org/ml/libc-alpha/2020-02/msg00453.html As soon as I have any news, I will reply there. If we remove the backchain fallback. I assume the s390 specific backtrace.c files can be removed. Thus the debug/backtrace.c would be used. But I have to double check at this time. If we still need the backchain fallback, I would either update the implementation in order to also get those "features": /* Check whether we make any progress. */ /* _Unwind_Backtrace seems to put NULL address above _start. Fix it up here. */ Or perhaps even better, add an architecture-fallback-hook in the default implementation. Bye, Stefan On 2/13/20 6:08 PM, Florian Weimer wrote: > --- > sysdeps/s390/s390-32/backtrace.c | 45 ++++++++++--------------------- > sysdeps/s390/s390-64/backtrace.c | 46 ++++++++++---------------------- > 2 files changed, 28 insertions(+), 63 deletions(-) > > diff --git a/sysdeps/s390/s390-32/backtrace.c b/sysdeps/s390/s390-32/backtrace.c > index 497e4f8875..21da6761f2 100644 > --- a/sysdeps/s390/s390-32/backtrace.c > +++ b/sysdeps/s390/s390-32/backtrace.c > @@ -17,12 +17,10 @@ > 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 <stddef.h> > #include <stdlib.h> > -#include <unwind.h> > +#include <unwind-link.h> > > /* This is a global variable set at program start time. It marks the > highest used stack address. */ > @@ -57,27 +55,11 @@ struct layout > struct trace_arg > { > void **array; > + struct unwind_link *unwind_link; > int cnt, size; > }; > > #ifdef SHARED > -static _Unwind_Reason_Code (*unwind_backtrace) (_Unwind_Trace_Fn, void *); > -static _Unwind_Ptr (*unwind_getip) (struct _Unwind_Context *); > - > -static void > -init (void) > -{ > - void *handle = __libc_dlopen ("libgcc_s.so.1"); > - > - if (handle == NULL) > - return; > - > - unwind_backtrace = __libc_dlsym (handle, "_Unwind_Backtrace"); > - unwind_getip = __libc_dlsym (handle, "_Unwind_GetIP"); > - if (unwind_getip == NULL) > - unwind_backtrace = NULL; > -} > - > static int > __backchain_backtrace (void **array, int size) > { > @@ -103,9 +85,6 @@ __backchain_backtrace (void **array, int size) > > return cnt; > } > -#else > -# define unwind_backtrace _Unwind_Backtrace > -# define unwind_getip _Unwind_GetIP > #endif > > static _Unwind_Reason_Code > @@ -116,7 +95,8 @@ 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; > return _URC_NO_REASON; > @@ -125,21 +105,24 @@ backtrace_helper (struct _Unwind_Context *ctx, void *a) > int > __backtrace (void **array, int size) > { > - struct trace_arg arg = { .array = array, .size = size, .cnt = -1 }; > + struct trace_arg arg = > + { > + .array = array, > + .unwind_link = __libc_unwind_link_get (), > + .size = size, > + .cnt = -1 > + }; > > if (size <= 0) > return 0; > > #ifdef SHARED > - __libc_once_define (static, once); > - > - __libc_once (once, init); > - > - if (unwind_backtrace == NULL) > + if (arg.unwind_link == NULL) > return __backchain_backtrace (array, size); > #endif > > - unwind_backtrace (backtrace_helper, &arg); > + UNWIND_LINK_PTR (arg.unwind_link, _Unwind_Backtrace) > + (backtrace_helper, &arg); > > return arg.cnt != -1 ? arg.cnt : 0; > } > diff --git a/sysdeps/s390/s390-64/backtrace.c b/sysdeps/s390/s390-64/backtrace.c > index 5d14e01280..1b8818f219 100644 > --- a/sysdeps/s390/s390-64/backtrace.c > +++ b/sysdeps/s390/s390-64/backtrace.c > @@ -17,13 +17,10 @@ > 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 <stddef.h> > #include <stdlib.h> > -#include <unwind.h> > - > +#include <unwind-link.h> > > /* This is a global variable set at program start time. It marks the > highest used stack address. */ > @@ -56,27 +53,11 @@ struct layout > struct trace_arg > { > void **array; > + struct unwind_link *unwind_link; > int cnt, size; > }; > > #ifdef SHARED > -static _Unwind_Reason_Code (*unwind_backtrace) (_Unwind_Trace_Fn, void *); > -static _Unwind_Ptr (*unwind_getip) (struct _Unwind_Context *); > - > -static void > -init (void) > -{ > - void *handle = __libc_dlopen ("libgcc_s.so.1"); > - > - if (handle == NULL) > - return; > - > - unwind_backtrace = __libc_dlsym (handle, "_Unwind_Backtrace"); > - unwind_getip = __libc_dlsym (handle, "_Unwind_GetIP"); > - if (unwind_getip == NULL) > - unwind_backtrace = NULL; > -} > - > static int > __backchain_backtrace (void **array, int size) > { > @@ -102,9 +83,6 @@ __backchain_backtrace (void **array, int size) > > return cnt; > } > -#else > -# define unwind_backtrace _Unwind_Backtrace > -# define unwind_getip _Unwind_GetIP > #endif > > static _Unwind_Reason_Code > @@ -115,7 +93,8 @@ 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; > return _URC_NO_REASON; > @@ -124,21 +103,24 @@ backtrace_helper (struct _Unwind_Context *ctx, void *a) > int > __backtrace (void **array, int size) > { > - struct trace_arg arg = { .array = array, .size = size, .cnt = -1 }; > + struct trace_arg arg = > + { > + .array = array, > + .unwind_link = __libc_unwind_link_get (), > + .size = size, > + .cnt = -1 > + }; > > if (size <= 0) > return 0; > > #ifdef SHARED > - __libc_once_define (static, once); > - > - __libc_once (once, init); > - > - if (unwind_backtrace == NULL) > + if (arg.unwind_link == NULL) > return __backchain_backtrace (array, size); > #endif > > - unwind_backtrace (backtrace_helper, &arg); > + UNWIND_LINK_PTR (arg.unwind_link, _Unwind_Backtrace) > + (backtrace_helper, &arg); > > return arg.cnt != -1 ? arg.cnt : 0; > } >
diff --git a/sysdeps/s390/s390-32/backtrace.c b/sysdeps/s390/s390-32/backtrace.c index 497e4f8875..21da6761f2 100644 --- a/sysdeps/s390/s390-32/backtrace.c +++ b/sysdeps/s390/s390-32/backtrace.c @@ -17,12 +17,10 @@ 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 <stddef.h> #include <stdlib.h> -#include <unwind.h> +#include <unwind-link.h> /* This is a global variable set at program start time. It marks the highest used stack address. */ @@ -57,27 +55,11 @@ struct layout struct trace_arg { void **array; + struct unwind_link *unwind_link; int cnt, size; }; #ifdef SHARED -static _Unwind_Reason_Code (*unwind_backtrace) (_Unwind_Trace_Fn, void *); -static _Unwind_Ptr (*unwind_getip) (struct _Unwind_Context *); - -static void -init (void) -{ - void *handle = __libc_dlopen ("libgcc_s.so.1"); - - if (handle == NULL) - return; - - unwind_backtrace = __libc_dlsym (handle, "_Unwind_Backtrace"); - unwind_getip = __libc_dlsym (handle, "_Unwind_GetIP"); - if (unwind_getip == NULL) - unwind_backtrace = NULL; -} - static int __backchain_backtrace (void **array, int size) { @@ -103,9 +85,6 @@ __backchain_backtrace (void **array, int size) return cnt; } -#else -# define unwind_backtrace _Unwind_Backtrace -# define unwind_getip _Unwind_GetIP #endif static _Unwind_Reason_Code @@ -116,7 +95,8 @@ 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; return _URC_NO_REASON; @@ -125,21 +105,24 @@ backtrace_helper (struct _Unwind_Context *ctx, void *a) int __backtrace (void **array, int size) { - struct trace_arg arg = { .array = array, .size = size, .cnt = -1 }; + struct trace_arg arg = + { + .array = array, + .unwind_link = __libc_unwind_link_get (), + .size = size, + .cnt = -1 + }; if (size <= 0) return 0; #ifdef SHARED - __libc_once_define (static, once); - - __libc_once (once, init); - - if (unwind_backtrace == NULL) + if (arg.unwind_link == NULL) return __backchain_backtrace (array, size); #endif - unwind_backtrace (backtrace_helper, &arg); + UNWIND_LINK_PTR (arg.unwind_link, _Unwind_Backtrace) + (backtrace_helper, &arg); return arg.cnt != -1 ? arg.cnt : 0; } diff --git a/sysdeps/s390/s390-64/backtrace.c b/sysdeps/s390/s390-64/backtrace.c index 5d14e01280..1b8818f219 100644 --- a/sysdeps/s390/s390-64/backtrace.c +++ b/sysdeps/s390/s390-64/backtrace.c @@ -17,13 +17,10 @@ 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 <stddef.h> #include <stdlib.h> -#include <unwind.h> - +#include <unwind-link.h> /* This is a global variable set at program start time. It marks the highest used stack address. */ @@ -56,27 +53,11 @@ struct layout struct trace_arg { void **array; + struct unwind_link *unwind_link; int cnt, size; }; #ifdef SHARED -static _Unwind_Reason_Code (*unwind_backtrace) (_Unwind_Trace_Fn, void *); -static _Unwind_Ptr (*unwind_getip) (struct _Unwind_Context *); - -static void -init (void) -{ - void *handle = __libc_dlopen ("libgcc_s.so.1"); - - if (handle == NULL) - return; - - unwind_backtrace = __libc_dlsym (handle, "_Unwind_Backtrace"); - unwind_getip = __libc_dlsym (handle, "_Unwind_GetIP"); - if (unwind_getip == NULL) - unwind_backtrace = NULL; -} - static int __backchain_backtrace (void **array, int size) { @@ -102,9 +83,6 @@ __backchain_backtrace (void **array, int size) return cnt; } -#else -# define unwind_backtrace _Unwind_Backtrace -# define unwind_getip _Unwind_GetIP #endif static _Unwind_Reason_Code @@ -115,7 +93,8 @@ 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; return _URC_NO_REASON; @@ -124,21 +103,24 @@ backtrace_helper (struct _Unwind_Context *ctx, void *a) int __backtrace (void **array, int size) { - struct trace_arg arg = { .array = array, .size = size, .cnt = -1 }; + struct trace_arg arg = + { + .array = array, + .unwind_link = __libc_unwind_link_get (), + .size = size, + .cnt = -1 + }; if (size <= 0) return 0; #ifdef SHARED - __libc_once_define (static, once); - - __libc_once (once, init); - - if (unwind_backtrace == NULL) + if (arg.unwind_link == NULL) return __backchain_backtrace (array, size); #endif - unwind_backtrace (backtrace_helper, &arg); + UNWIND_LINK_PTR (arg.unwind_link, _Unwind_Backtrace) + (backtrace_helper, &arg); return arg.cnt != -1 ? arg.cnt : 0; }