zdb/ztest: use libspl backtrace for crashes

We can show much nicer backtraces these days, lets use them.

Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by: Rob Norris <[email protected]>
Closes openzfs#16181
(cherry picked from commit e7b4519)

Author: robn

cmd/zdb/zdb.c

@@ -84,9 +84,6 @@
 #include <sys/brt_impl.h>
 #include <zfs_comutil.h>
 #include <sys/zstd/zstd.h>
-#if (__GLIBC__ && !__UCLIBC__)
-#include <execinfo.h> /* for backtrace() */
-#endif
 
 #include <libnvpair.h>
 #include <libzutil.h>
@@ -941,18 +938,11 @@ dump_debug_buffer(void)
 	zfs_dbgmsg_print("zdb");
 }
 
-#define	BACKTRACE_SZ	100
-
 static void sig_handler(int signo)
 {
 	struct sigaction action;
-#if (__GLIBC__ && !__UCLIBC__) /* backtrace() is a GNU extension */
-	int nptrs;
-	void *buffer[BACKTRACE_SZ];
 
-	nptrs = backtrace(buffer, BACKTRACE_SZ);
-	backtrace_symbols_fd(buffer, nptrs, STDERR_FILENO);
-#endif
+	libspl_dump_backtrace();
 	dump_debug_buffer();
 
 	/*

cmd/ztest.c

@@ -136,9 +136,6 @@
 #include <libzutil.h>
 #include <sys/crypto/icp.h>
 #include <sys/zfs_impl.h>
-#if (__GLIBC__ && !__UCLIBC__)
-#include <execinfo.h> /* for backtrace() */
-#endif
 
 static int ztest_fd_data = -1;
 static int ztest_fd_rand = -1;
@@ -597,18 +594,11 @@ dump_debug_buffer(void)
 	zfs_dbgmsg_print("ztest");
 }
 
-#define	BACKTRACE_SZ	100
-
 static void sig_handler(int signo)
 {
 	struct sigaction action;
-#if (__GLIBC__ && !__UCLIBC__) /* backtrace() is a GNU extension */
-	int nptrs;
-	void *buffer[BACKTRACE_SZ];
 
-	nptrs = backtrace(buffer, BACKTRACE_SZ);
-	backtrace_symbols_fd(buffer, nptrs, STDERR_FILENO);
-#endif
+	libspl_dump_backtrace();
 	dump_debug_buffer();
 
 	/*

lib/libspl/assert.c

@@ -55,7 +55,7 @@
 #define	UNW_LOCAL_ONLY
 #include <libunwind.h>
 
-static inline void
+void
 libspl_dump_backtrace(void)
 {
 	unw_context_t uc;
@@ -85,7 +85,7 @@ libspl_dump_backtrace(void)
 #elif defined(HAVE_BACKTRACE)
 #include <execinfo.h>
 
-static inline void
+void
 libspl_dump_backtrace(void)
 {
 	void *btptrs[100];
@@ -97,7 +97,10 @@ libspl_dump_backtrace(void)
 	free(bt);
 }
 #else
-#define	libspl_dump_backtrace()
+void
+libspl_dump_backtrace(void)
+{
+}
 #endif
 
 #if defined(__APPLE__)

lib/libspl/include/assert.h

@@ -60,6 +60,8 @@ libspl_assert(const char *buf, const char *file, const char *func, int line)
 	return (0);
 }
 
+extern void libspl_dump_backtrace(void);
+
 #ifdef verify
 #undef verify
 #endif