perf llvm: Reduce LLVM initialization

Move the 3 LLVM initialization routines to be called in a single
init_llvm function that has its own bool to avoid repeated
initialization.

Reduce the scope of triplet and avoid copying strings for x86.

Signed-off-by: Ian Rogers <[e-mail]>
Cc: Adrian Hunter <[e-mail]>
Cc: Alexander Shishkin <[e-mail]>
Cc: Alexandre Ghiti <[e-mail]>
Cc: Andi Kleen <[e-mail]>
Cc: Athira Rajeev <[e-mail]>
Cc: Bill Wendling <[e-mail]>
Cc: Charlie Jenkins <[e-mail]>
Cc: Collin Funk <[e-mail]>
Cc: Dmitriy Vyukov <[e-mail]>
Cc: Dr. David Alan Gilbert <[e-mail]>
Cc: Eric Biggers <[e-mail]>
Cc: Haibo Xu <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: James Clark <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Cc: Justin Stitt <[e-mail]>
Cc: Li Huafei <[e-mail]>
Cc: Masami Hiramatsu <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Cc: Nathan Chancellor <[e-mail]>
Cc: Nick Desaulniers <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Song Liu <[e-mail]>
Cc: Stephen Brennan <[e-mail]>
[ Move init_llvm() under HAVE_LIBLLVM_SUPPORT to fix the build ]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/util/llvm.c

···
 	/* Nothing to free. */
 }
 
+#ifdef HAVE_LIBLLVM_SUPPORT
+static void init_llvm(void)
+{
+	static bool init;
 
-#if defined(HAVE_LIBLLVM_SUPPORT)
+	if (!init) {
+		LLVMInitializeAllTargetInfos();
+		LLVMInitializeAllTargetMCs();
+		LLVMInitializeAllDisassemblers();
+		init = true;
+	}
+}
+
 struct find_file_offset_data {
 	u64 ip;
 	u64 offset;
···
 	u64 len;
 	u64 pc;
 	bool is_64bit;
-	char triplet[64];
 	char disasm_buf[2048];
 	size_t disasm_len;
 	struct disasm_line *dl;
···
 	if (args->options->objdump_path)
 		return -1;
 
-	LLVMInitializeAllTargetInfos();
-	LLVMInitializeAllTargetMCs();
-	LLVMInitializeAllDisassemblers();
-
 	buf = read_symbol(filename, map, sym, &len, &is_64bit);
 	if (buf == NULL)
 		return -1;
 
+	init_llvm();
 	if (arch__is(args->arch, "x86")) {
-		if (is_64bit)
-			scnprintf(triplet, sizeof(triplet), "x86_64-pc-linux");
-		else
-			scnprintf(triplet, sizeof(triplet), "i686-pc-linux");
+		const char *triplet = is_64bit ? "x86_64-pc-linux" : "i686-pc-linux";
+
+		disasm = LLVMCreateDisasm(triplet, &storage, /*tag_type=*/0,
+					  /*get_op_info=*/NULL, symbol_lookup_callback);
 	} else {
+		char triplet[64];
+
 		scnprintf(triplet, sizeof(triplet), "%s-linux-gnu",
 			  args->arch->name);
+		disasm = LLVMCreateDisasm(triplet, &storage, /*tag_type=*/0,
+					  /*get_op_info=*/NULL, symbol_lookup_callback);
 	}
 
-	disasm = LLVMCreateDisasm(triplet, &storage, 0, NULL,
-				  symbol_lookup_callback);
 	if (disasm == NULL)
 		goto err;