perf llvm: Return -ENOMEM when asprintf() fails

Zhihao sent a patch but it made llvm__compile_bpf() return what
asprintf() returns on error, which is just -1, but since this function
returns -errno, fix it by returning -ENOMEM for this case instead.

Fixes: cb76371 ("perf llvm: Allow passing options to llc ...")
Fixes: 5eab5a7 ("perf llvm: Display eBPF compiling command ...")
Reported-by: Hulk Robot <[email protected]>
Reported-by: Zhihao Cheng <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Andrii Nakryiko <[email protected]>
Cc: Daniel Borkmann <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Nathan Chancellor <[email protected]>
Cc: Nick Desaulniers <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Yu Kuai <[email protected]>
Cc: [email protected]
Link: http://lore.kernel.org/lkml/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

tools/perf/util/llvm-utils.c

@@ -504,6 +504,7 @@ int llvm__compile_bpf(const char *path, void **p_obj_buf,
 			goto errout;
 		}
 
+		err = -ENOMEM;
 		if (asprintf(&pipe_template, "%s -emit-llvm | %s -march=bpf %s -filetype=obj -o -",
 			      template, llc_path, opts) < 0) {
 			pr_err("ERROR:\tnot enough memory to setup command line\n");
@@ -524,6 +525,7 @@ int llvm__compile_bpf(const char *path, void **p_obj_buf,
 
 	pr_debug("llvm compiling command template: %s\n", template);
 
+	err = -ENOMEM;
 	if (asprintf(&command_echo, "echo -n \"%s\"", template) < 0)
 		goto errout;