[PATCH v3 4/6] perf tool: Move usage strings and functions to perf.c

[Ian Rogers <irogers@google.com>]

The code is mostly used by perf.c with additional unused functionality
such as function pointers derived from early git code. Moving it into
perf.c directly reduces the code footprint, drops the util/util.h
dependence from perf.c, and allows us to remove util/usage.c entirely.

The string constants are exposed in builtin.h, as they are used
in builtin-help.c.

Signed-off-by: Ian Rogers <irogers@google.com>
Assisted-by: Antigravity:gemini-3.1-pro
---
 tools/perf/builtin.h    |  3 +++
 tools/perf/perf.c       | 13 ++++++++++++-
 tools/perf/util/Build   |  1 -
 tools/perf/util/usage.c | 34 ----------------------------------
 tools/perf/util/util.h  |  4 ----
 5 files changed, 15 insertions(+), 40 deletions(-)
 delete mode 100644 tools/perf/util/usage.c

diff --git a/tools/perf/builtin.h b/tools/perf/builtin.h
index 40c4078c295f..e0b430821abc 100644
--- a/tools/perf/builtin.h
+++ b/tools/perf/builtin.h
@@ -2,6 +2,9 @@
 #ifndef BUILTIN_H
 #define BUILTIN_H
 
+extern const char perf_usage_string[];
+extern const char perf_more_info_string[];
+
 struct feature_status {
 	const char *name;
 	const char *macro;
diff --git a/tools/perf/perf.c b/tools/perf/perf.c
index 7e2e667b011f..65bdfd71f626 100644
--- a/tools/perf/perf.c
+++ b/tools/perf/perf.c
@@ -31,7 +31,18 @@
 #include "util/build-id.h"
 #include "util/config.h"
 #include "util/debug.h"
-#include "util/util.h" // usage()
+
+const char perf_usage_string[] =
+	"perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
+
+const char perf_more_info_string[] =
+	"See 'perf help COMMAND' for more information on a specific command.";
+
+static void __noreturn usage(const char *err)
+{
+	fprintf(stderr, "\n Usage: %s\n", err);
+	exit(129);
+}
 
 #define CMD_EXEC_PATH "--exec-path"
 #define CMD_DEBUGFS_DIR "--debugfs-dir="
diff --git a/tools/perf/util/Build b/tools/perf/util/Build
index b26a0b1ddfa3..d08f2af7d970 100644
--- a/tools/perf/util/Build
+++ b/tools/perf/util/Build
@@ -54,7 +54,6 @@ perf-util-y += string.o
 perf-util-y += strlist.o
 perf-util-y += strfilter.o
 perf-util-y += top.o
-perf-util-y += usage.o
 perf-util-y += dso.o
 perf-util-y += dsos.o
 perf-util-y += symbol.o
diff --git a/tools/perf/util/usage.c b/tools/perf/util/usage.c
deleted file mode 100644
index 4c8ffbad2323..000000000000
--- a/tools/perf/util/usage.c
+++ /dev/null
@@ -1,34 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * usage.c
- *
- * Various reporting routines.
- * Originally copied from GIT source.
- *
- * Copyright (C) Linus Torvalds, 2005
- */
-#include "util.h"
-#include <stdio.h>
-#include <stdlib.h>
-#include <linux/compiler.h>
-
-const char perf_usage_string[] =
-	"perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
-
-const char perf_more_info_string[] =
-	"See 'perf help COMMAND' for more information on a specific command.";
-
-static __noreturn void usage_builtin(const char *err)
-{
-	fprintf(stderr, "\n Usage: %s\n", err);
-	exit(129);
-}
-
-/* If we are in a dlopen()ed .so write to a global variable would segfault
- * (ugh), so keep things static. */
-static void (*usage_routine)(const char *err) __noreturn = usage_builtin;
-
-void usage(const char *err)
-{
-	usage_routine(err);
-}
diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
index 87a0818a8c76..f8f1ff603c72 100644
--- a/tools/perf/util/util.h
+++ b/tools/perf/util/util.h
@@ -17,9 +17,6 @@
 #include <internal/cpumap.h>
 #endif
 
-extern const char perf_usage_string[];
-extern const char perf_more_info_string[];
-
 extern const char *input_name;
 
 /* This will control if perf_{host,guest} will set attr.exclude_{host,guest}. */
@@ -29,7 +26,6 @@ extern bool perf_host;
 extern bool perf_guest;
 
 /* General helper functions */
-void usage(const char *err) __noreturn;
 
 struct dirent;
 struct strlist;
-- 
2.55.0.966.g6673acef38-goog