From f94fe7048a352ff8914232a18e2e2f18f8a5ac81 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Mon, 30 Jan 2023 14:02:37 +0100 Subject: [PATCH] ftrace: sample: avoid open-coded 64-bit division Calculating the average period requires a 64-bit division that leads to a link failure on 32-bit architectures: x86_64-linux-ld: samples/ftrace/ftrace-ops.o: in function `ftrace_ops_sample_init': ftrace-ops.c:(.init.text+0x23b): undefined reference to `__udivdi3' Use the div_u64() helper to do this instead. Since this is an init function that is not called frequently, the runtime overhead is going to be acceptable. Link: https://lore.kernel.org/linux-trace-kernel/20230130130246.247537-1-arnd@kernel.org Cc: Masami Hiramatsu Fixes: b56c68f705ca ("ftrace: Add sample with custom ops") Signed-off-by: Arnd Bergmann Acked-by: Mark Rutland Signed-off-by: Steven Rostedt (Google) --- samples/ftrace/ftrace-ops.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/samples/ftrace/ftrace-ops.c b/samples/ftrace/ftrace-ops.c index 24deb51c7261..0c8da87ff5c3 100644 --- a/samples/ftrace/ftrace-ops.c +++ b/samples/ftrace/ftrace-ops.c @@ -223,7 +223,7 @@ static int __init ftrace_ops_sample_init(void) pr_info("Attempted %u calls to %ps in %lluns (%lluns / call)\n", nr_function_calls, tracee_relevant, - period, period / nr_function_calls); + period, div_u64(period, nr_function_calls)); if (persist) return 0; -- 2.34.1