Commit f94fe704 authored by Arnd Bergmann's avatar Arnd Bergmann Committed by Steven Rostedt (Google)

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 <mhiramat@kernel.org>
Fixes: b56c68f7 ("ftrace: Add sample with custom ops")
Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
Acked-by: default avatarMark Rutland <mark.rutland@arm.com>
Signed-off-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
parent 01678fbc
...@@ -223,7 +223,7 @@ static int __init ftrace_ops_sample_init(void) ...@@ -223,7 +223,7 @@ static int __init ftrace_ops_sample_init(void)
pr_info("Attempted %u calls to %ps in %lluns (%lluns / call)\n", pr_info("Attempted %u calls to %ps in %lluns (%lluns / call)\n",
nr_function_calls, tracee_relevant, nr_function_calls, tracee_relevant,
period, period / nr_function_calls); period, div_u64(period, nr_function_calls));
if (persist) if (persist)
return 0; return 0;
......
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