perf tools: Convert to LIBUNWIND_SUPPORT

For building perf without libunwind, we can set NO_LIBUNWIND=1 as a
argument of make.  It then defines NO_LIBUNWIND_SUPPORT macro for C code
to do the proper handling.  However it usually used in a negative
semantics - e.g. #ifndef - so we saw double negations which can be
misleading.  Convert it to a positive form to make it more readable.

Also change NO_PERF_REGS macro to HAVE_PERF_REGS for the same reason.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1348824728-14025-5-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/Makefile

@@ -535,9 +535,8 @@ endif # PERF_HAVE_DWARF_REGS
 endif # NO_DWARF
 endif # NO_LIBELF
 
-ifdef NO_LIBUNWIND
-	BASIC_CFLAGS += -DNO_LIBUNWIND_SUPPORT
-else
+ifndef NO_LIBUNWIND
+	BASIC_CFLAGS += -DLIBUNWIND_SUPPORT
 	EXTLIBS += $(LIBUNWIND_LIBS)
 	BASIC_CFLAGS := $(LIBUNWIND_CFLAGS) $(BASIC_CFLAGS)
 	BASIC_LDFLAGS := $(LIBUNWIND_LDFLAGS) $(BASIC_LDFLAGS)
@@ -747,8 +746,7 @@ ifeq ($(NO_PERF_REGS),0)
 	ifeq ($(ARCH),x86)
 		LIB_H += arch/x86/include/perf_regs.h
 	endif
-else
-	BASIC_CFLAGS += -DNO_PERF_REGS
+	BASIC_CFLAGS += -DHAVE_PERF_REGS
 endif
 
 ifdef NO_STRLCPY

tools/perf/builtin-record.c

@@ -33,11 +33,11 @@
 
 #define CALLCHAIN_HELP "do call-graph (stack chain/backtrace) recording: "
 
-#ifdef NO_LIBUNWIND_SUPPORT
-static char callchain_help[] = CALLCHAIN_HELP "[fp]";
-#else
+#ifdef LIBUNWIND_SUPPORT
 static unsigned long default_stack_dump_size = 8192;
 static char callchain_help[] = CALLCHAIN_HELP "[fp] dwarf";
+#else
+static char callchain_help[] = CALLCHAIN_HELP "[fp]";
 #endif
 
 enum write_mode_t {
@@ -800,7 +800,7 @@ error:
 	return ret;
 }
 
-#ifndef NO_LIBUNWIND_SUPPORT
+#ifdef LIBUNWIND_SUPPORT
 static int get_stack_size(char *str, unsigned long *_size)
 {
 	char *endptr;
@@ -826,7 +826,7 @@ static int get_stack_size(char *str, unsigned long *_size)
 	       max_size, str);
 	return -1;
 }
-#endif /* !NO_LIBUNWIND_SUPPORT */
+#endif /* LIBUNWIND_SUPPORT */
 
 static int
 parse_callchain_opt(const struct option *opt __maybe_unused, const char *arg,
@@ -865,7 +865,7 @@ parse_callchain_opt(const struct option *opt __maybe_unused, const char *arg,
 				       "needed for -g fp\n");
 			break;
 
-#ifndef NO_LIBUNWIND_SUPPORT
+#ifdef LIBUNWIND_SUPPORT
 		/* Dwarf style */
 		} else if (!strncmp(name, "dwarf", sizeof("dwarf"))) {
 			ret = 0;
@@ -883,7 +883,7 @@ parse_callchain_opt(const struct option *opt __maybe_unused, const char *arg,
 			if (!ret)
 				pr_debug("callchain: stack dump size %d\n",
 					 rec->opts.stack_dump_size);
-#endif /* !NO_LIBUNWIND_SUPPORT */
+#endif /* LIBUNWIND_SUPPORT */
 		} else {
 			pr_err("callchain: Unknown -g option "
 			       "value: %s\n", arg);

tools/perf/util/perf_regs.h

@@ -1,7 +1,7 @@
 #ifndef __PERF_REGS_H
 #define __PERF_REGS_H
 
-#ifndef NO_PERF_REGS
+#ifdef HAVE_PERF_REGS
 #include <perf_regs.h>
 #else
 #define PERF_REGS_MASK	0
@@ -10,5 +10,5 @@ static inline const char *perf_reg_name(int id __maybe_unused)
 {
 	return NULL;
 }
-#endif /* NO_PERF_REGS */
+#endif /* HAVE_PERF_REGS */
 #endif /* __PERF_REGS_H */

tools/perf/util/unwind.h

@@ -13,7 +13,7 @@ struct unwind_entry {
 
 typedef int (*unwind_entry_cb_t)(struct unwind_entry *entry, void *arg);
 
-#ifndef NO_LIBUNWIND_SUPPORT
+#ifdef LIBUNWIND_SUPPORT
 int unwind__get_entries(unwind_entry_cb_t cb, void *arg,
 			struct machine *machine,
 			struct thread *thread,
@@ -31,5 +31,5 @@ unwind__get_entries(unwind_entry_cb_t cb __maybe_unused,
 {
 	return 0;
 }
-#endif /* NO_LIBUNWIND_SUPPORT */
+#endif /* LIBUNWIND_SUPPORT */
 #endif /* __UNWIND_H */